Presentation Abstracts

Protein and Co-Products sessions and posters.

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MONDAY

AFTERNOON

PCP 1: Biofuel Co-Products: Recovery, Value Addition, and Sustainability

Chair(s): K. Liu, USDA, ARS, USA; H. Wang, Iowa State University, USA; and J. Wanasundara, Agriculture and Agri-Food Canada, Canada

Increasing Protein Content of DDGS in Corn Dry Grind Process. S. Li, W. Liu, K. Rausch, M. Tumbleson, V. Singh, University of Illinois at Urbana-Champaign, Urbana, IL, USA

Distillers dried grains with solubles (DDGS) with is a coproduct of conventional dry grind ethanol plant. Due to its high fiber content, DDGS is used primarily as ingredient in ruminant animal diets. Reducing fiber and increasing protein content will allow DDGS use as an ingredient in poultry and swine diets. Increase in protein and decrease in fiber content of DDGS can be achieved by modified dry grind corn process (E-Mill process) that fractionates corn kernel (to recover germ and fiber as coproducts) prior to fermentation (2). Further increase in protein content and decrease in fiber content can be achieved by extraction of oligosaccharides and other soluble carbohydrates or by acid precipitation of the protein from E-Mill DDGS. E-Mill DDGS was further processed to produce protein isolate (PI) and concentrate (PC) products. The yield and protein content of PI and PC products were determined. PC protein content greater than 60% was achieved. 1. Liu, K. 2011. Chemical composition of distillers grains, a review. Agric. Food Chem. 59: 1508-1526.2. Singh, V., Johnston, D. B., Naidu, K., Rausch, K. D., Belyea, R. L., and Tumbleson, M. E. 2005. Comparison of modified dry-grind corn processes for fermentation characteristics and DDGS composition. Cereal Chem. 82:187-19.

New Value-added Coproducts from Grain-based Ethanol Production by a Patent-pending Recovery Method. Keshun Liu, Frederic Barrows, USDA, ARS, USA

The production of fuel ethanol in the United States and elsewhere is a quickly growing industry. At present, a major co-product of the ethanol industry is corn distiller's dried grains with solubles (DDGS), the primary use is in the livestock industry. However, DDGS typically has characteristics that limit the inclusion level or value for animal feeds. For example, DDGS is highly variable in composition and contains high levels of phosphorus (P), sulfur (S) and some other minerals. At USDA-ARS, we have developed a novel method to recover co-products from the dry-grind process. The new method not only produces distiller grains with much less variable composition but also gives three new co-products with unique new composition. First, an ash-rich fraction (ash content around 30%, dry matter basis) is a good mineral supplement for feed or food. Second, a modified solubles product has increased protein and reduced fat and ash contents. Third, an oil-rich fraction can be a feedstock for biodiesel production. When both mineral supplement and modified soluble product were fed to rainbow trout, an increase in the digestibility of energy, dry matter, fat, phosphorus, and some essential amino acids (such as lysine and threonine) was observed. Long term feeding trials on rainbow trout with these products are underway.

Value-addition to Dry-Grind Co-Products: α-zein Extraction and Characterization for Non-food Use. B.P. Lamsal, Iowa State University, Ames, IA, USA

Zein was recovered from corn distiller’s dried grains with solubles (DDGS) by a modified method using 70% (w/w) aqueous 2-propanol (70-IPA) or 70% (v/v) aqueous ethanol (70-EtOH) solvents, and a commercial method using 88% (w/w) aqueous 2-propanol (88-IPA). Yield, purity, and film properties of the isolated zein were determined. The modified procedure extracted two fractions of zeins: a mostly α-zein fraction, and a mostly γ- zein fraction. The modified method increased α-zein yield from 4 to 14%. Enzyme cellulase pretreatment did not improve zein yield, but grinding did. The α-zein fraction showed electrophoretic bands at 40, 22, 19, and 10 kDa, corresponding to α-zein dimer, α1-zein, α2-zein, and δ-zein, respectively. The α-zein of DDGS retained its film forming capability. The α-zein film of unmodified DDGS was cloudy and rough, unlike the clear and smooth films of α-zeins isolated from corn gluten meal and enzyme-treated DDGS.

Microalgal Protein Isolation from Nannochloropsis spp. Defatted Biomass. J.A. Gerde¹, L. Yao¹, S. Jung¹, B. Lamsal¹, L.A. Johnson^2,1, T. Wang¹, ¹Dept. of Food Science and Human Nutrition Iowa State University, Ames, Iowa, USA, ²Center for Crops Utilization Research Iowa State University, Ames, Iowa, USA

Nannochloropsis spp. is a marine photosynthetic microalgae that produces approximately 20% lipids and 35% protein. Oil extraction models on this alga have been developed for the production of biofuels. The remaining biomass was extracted under alkaline conditions to produce an algal protein isolate. All the streams were quantified and characterized for peptides, amino acid composition, nitrogen content, and carbohydrates.

Challenges in Extraction and Recovery of Algae Biofuel Co-products. R. Green, POS Bio-Sciences, Saskatoon, SK, Canada

Algal lipids offer considerable promise for conversion into renewable biofuels. The utilization of co-products from the remaining residual biomass however, is critical for the commercial viability of algae processing. High value co-products may include the meal, polyunsaturated fatty acids, proteins, fiber, carotenoids, phytosterols, and antimicrobial agents. The algae harvesting and lipid extraction techniques will affect the availability of potential co-products remaining in the extracted algal solids. Generation of heat due to friction during disruption of algal cells may degrade valuable protein and secondary metabolites. Solvent extraction of the lipids may extract valuable co-products which are difficult to separate from the resulting oil fraction. Specific compounds may also be denatured depending on the solvent used. If the target co-products are to be utilized for food and feed ingredients, certain anti-nutrients or unpalatable compounds may be difficult to remove. Other target compounds may be conjugated with structural components of the algae biomass and require hydrolysis to be recovered. The preservation and effective recovery of co-products need to be considered in the design of an effective algae biofuel processing scheme.

Investigation of Net Shape Forming of Protein Based Plastics for Industrial Applications. David Grewell, Gowrishankar Srinivasan, Iowa State University, Ames, IA, USA

Processability of plant-based protein and oil plastics was investigated by extrusion, injection molding, casting and compression molding. The goal of this work was to develop formulations that could meet industrial spefications. Applications included, lubrication sticks, plant pots, chew toys and chemical delivery applications. The mechanical properties were enhanced the addition of crosslinking agents such as glyoxal trimer di-hydrate (GTD), phthalic anhydride and natural fibers like coconut fiber husks (CFH) and corn cobs (CC). It was observed that plastics with GTD cross-linkers and composite plastics processed with CFH exhibited superior properties. Another objective was to improve water stability of soy protein isolate (SPI) plastics by using commercial plasticizers as crosslinking modifiers.

Barley Oil as a Co-Product of Hulled and Hulless Barley. R.A. Moreau, K.B. Hicks, D.B. Johnston, Eastern Regional Research Center, ARS, USDA, Wyndmoor, PA, USA

Barley (Hordeum vulgare) is an ancient grain that was domesticated for use as a food. Currently only about 2% is used for food, about two thirds is use for animal feed and one third for malting. Because the oil content of most barley cultivars is low (<2%), obtaining oil from whole barley grain is not easy or economical. However, when barley is milled by various methods some of its milling fractions are enriched in oil (up to about 10%) and these fractions have been used to produce barley oil. Barley oil is a high-linoleate oil, whose fatty acid composition is similar to corn oil and several other commodity plant oils. The composition of phytosterols in barley oil is higher than in most commodity plant oils. The most unique feature about barley oil is the very high levels of tocotrienols (especially alpha-tocotrienol). Several studies have demonstrated health-promoting properties of barley oil. The health promoting property that has received the most attention is the ability of barley oil to reduce the levels of serum cholesterol in laboratory animals and in humans, which is attributed to its high levels of tocotrienols.

TUESDAY

MORNING

PCP 2: Bioactive Food Proteins and Peptides I - Fundamentals

Chair(s): H. Ibrahim, Kagoshima University, Japan; and H. Kumagai, Nihon University, Japan

D-Amino Acid as a Novel Biofactor. T. Yoshimura, S. Kato, T. Ito, H. Hemmi, Nagoya University, Nagoya, Aich, Japan

Recent advances in analytical techniques have demonstrated the various D-amino acids are distributed in eukaryotes including mammals and bear important physiological functions. For example, D-serine acts as a co-agonist of N-methyl-D-aspartate receptor (NMDA), an excitatory glutamate receptors in mammalian brain. Relationship has been reported between D-serine and central nervous system diseases. For example, the amount of D-serine and the relative ratio of D-serine to (D+L)-serine are significantly decreased in serum and frontal lobe of schizophrenia or Alzheimer's disease patients, and an excess amount of D-serine is produced in the spinal fluid of amyotrophic lateral sclerosis patients. D-Asp is involved in the hormone secretion regulations, and probably plays a role in mammalian fertilization processes. D-Ser and D-Asp are endogenously synthesized, however the exogenously supplied D-amino acids are transported to their site of action. We thus cannot rule out the possibility that D-amino acids in food have some physiological functions in mammals. In this presentation, I will introduce the physiological functions of D-amino acids, and presence and formation of D-amino acids in the fermented foods.This work was supported in part by the Program for Promotion of Basic and Applied Researches for Innovation in Bio-oriented Industry (BRAIN).

Fermentation of GABA Enriched Salt-free Soybean Paste and its Application. Hajime Hatta¹, Sakiko Shou¹, Yoshie Ueno², ¹Kyoto Women's University, Kyoto, Japan, ²Kyoto Prefectural Technology Center, Kyoto, Japan

γ-aminobutylic acid (GABA) is generated from glutamic acid by glutamic acid decarboxylase (GAD). It is found, for example, in fermented soybean paste, because the GAD of lactic acid bacteria produced GABA during its fermentation. Orally administered GABA reduced blood pressure (BP), therefore, GABA enriched foods have been in the Japanese market as the food for specified health uses (FOSHU). Here, we attempted to develop GABA enriched salt-free soybean paste for people recommended to intake low salt diets. Three species of bacteria (Lactobacillus brevis IFO 12005、L. hilgardii K-3、L.buchneri JCM 1115) were compared for the efficiency of GABA production during salt-free fermentation with and without adding ethanol as a preservative. L. hilgardii K-3 was found to be the most effective bacterium for GABA production after 2-week salt-free fermentation; although all the soybean pastes were spoiled without the addition of ethanol. The spoiling was prevented by adding 2% ethanol without changing an efficiency of GABA production. However, the GABA production was decreased at 3% of ethanol or more. Finally, we succeeded in producing GABA enriched salt-free soybean paste which contains 0.2% GABA. Since daily intake of 20 mg GABA is reported to be necessary for reducing BP, about 10g of the GABA enriched soybean paste per serve is adequate for us to expect lowering BP.

Orally Active Neuromodulatory Peptides. Kousaku Ohinata, Kyoto University, Uji, Kyoto, Japan

Endogenous neuropeptides, playing important roles in rapid neural signaling, usually exhibit potent activities after central but not after oral administration; however, low-molecular-weight peptides derived from food proteins sometime have neuromodulatory actions even after oral administration. Intriguingly, dipeptides can be produced industrially both by the enzymatic digestion of proteins and by a novel method based on L-amino acid α-ligase.We found that Tyr-Leu (YL) has potent anxiolytic-like activity comparable to diazepam after oral administration on employing the elevated plus-maze test in mice. The YL-induced anxiolytic-like activity was blocked by an antagonist of serotonin 5-HT_1A, dopamine D₁ or GABA_A receptor; however, YL exhibited no affinity for these receptors. Taken together, the anxiolytic-like activity of YL was mediated by the activation of 5-HT_1A and dopamine D₁ receptor, followed by GABA_A receptor. A structure-activity relationship study revealed that C-terminal but not N-terminal elongation of YL might be tolerated for the anxiolytic activity. YL sequences are present in the primary structure of natural food proteins. Food protein-derived peptides with a YL sequence after digestion by enzymes present in the gastrointestinal tract might potentially contribute to satisfaction in the post-prandial state. We also introduce the other neuromodulatory peptides.

Suppressive Effect of Buckwheat Albumin against the Elevation of Blood Glucose. Kazumi Ninomiya, Shigenobu Ina, Makoto Akao, Hitomi Kumagai, Nihon University, Fujisawa-shi, Kanagawa, Japan

Type-2 diabetes is prevalent in the world, and control of the daily diet is crucial to prevent it. Wheat albumin is known to be effective to suppress postprandial hyperglycemia because it has inhibitory activity against α-amylase. However, the activity of proteins in other cereals has not been fully understood yet. This study examined the inhibitory activity of buckwheat albumin against α-amylase and its suppressive effect against postprandial hyperglycemia. An α-amylase inhibitor was purified from the buckwheat albumin fraction. The inhibitory activity of the α-amylase inhibitor against α-amylase from various sources, its digestibility and thermal stability were examined. Then, the α-amylase inhibitor was administered to rats together with starch, and blood glucose level was measured. The α-amylase inhibitor inhibited α-amylase from porcine pancreas and mealworm, but not that from human saliva. It maintained high α-amylase inhibitory activity even after digestion by pepsin and trypsin or after heat treatment. The α-amylase inhibitor suppressed the elevation of the blood glucose level after the ingestion of starch.

Bioactive Amino Acid that Prevents Hepatic Injury. H. Kumagai, Nihon University, Fujisawa-shi, Japan

S-Alk(en)yl-L-cysteine sulfoxides are odorless water-soluble amino acids found in Allium plants such as garlic and onion. S-Allyl-L-cysteine sulfoxide (ACSO) is the major one in garlic, whereas S-propenyl-L-cysteine sulfoxide (PeCSO) is the major one in onion. S-Methyl-L-cysteine sulfoxide (MCSO) is contained in both garlic and onion. These sulfoxides are converted by C-S lyase into sulfides that characterize the flavor of the plants when the plants are cut. Although these sulfides are known to be highly bioactive, their odor is sometimes too strong to be acceptable. However, the odor is not produced if C-S lyase is inactivated. Therefore, if S-alk(en)yl-L-cysteine sulfoxides, odor precursors, are converted into active compounds in the body after digestion and absorption, it would be possible to prepare “odorless garlic” that has the same function as common garlic.  In this study, ACSO, the major odor precursor in garlic, was administered to rats to examine if it would prevent hepatic injury induced by carbon tetrachloride.  Orally-administered ACSO suppressed the elevation of AST, ALT, LDH, and TBARS value, indicating that it prevented hepatic injury. It also induced the activities of phase II enzymes. These effects were characteristic of ACSO, but were not seen with other S-alk(en)yl-L-cysteine sulfoxides or S-alk(en)yl-L-cysteine.

Nutritional Aspect of β-conglycinin and its Physiological Function - Interaction with Body-fat Reducing Potential of CLA. Kazunori Koba¹, Daichi Oikawa², Shizuka Tamaru¹, Kazunari Tanaka¹, Michihiro Sugano³, ¹University of Nagasaki, Siebold, Nagayo, Nagasaki, Japan, ²Nagasaki University, Nagasaki, Japan, ³Professor Emeritus, Kyushu University, Fukuoka, Japan

Beta-conglycinin (CON), a major component of soy protein (SPI), is suggested to be responsible for serum and liver triglyceride reducing potential of SPI. However, CON as compared with casein (CAS) and SPI lowers body weight gain in rats as a result of the decrease in food consumption. To add essential amino acids, Thr, Val, Met, Tyr and Trp, to CON at the levels equivalent to those in CAS completely ameliorated the decrease of food consumption. This manipulation resulted in a decrease of serum and liver triglyceride concentrations. Thus, essential amino acid profile is at least responsible for a CON-dependent reduction of food consumption. In a separate study, we confirmed that the deficiency of Met and Trp of CON caused a reduction of food consumption. Also, CON-dependent reduction of food consumption disappeared, keeping the triglyceride lowering effect when CON was replaced with CAS at the 1:1 ratio.We also examined how the combination of CON and CLA modulates the lipid metabolism in rats. The results suggested that body fat-reducing potential of CLA was more evident in combination with CON than with SPI. This effect could be partly due to decreased fatty acid synthesis and increased β-oxidation in the liver.

Bioactivity of Protein and Phenolic Extracts of Brewer's Spent Grain (BSG) - Assessment of Their DNA Protective Effect Against Oxidant-induced DNA Single Strand Breaks in U937 Cells. N.M. O'Brien¹, A.L. McCarthy¹, Y.C. O'Callaghan¹, A. Connolly^2,1, C.O. Piggott^2,1, R.J. FitzGerald^2,1, ¹University College Cork, Cork, Ireland, ²University of Limerick, Limerick, Ireland

Brewer's Spent Grain (BSG), is a valuable source of bioactive ingredients, specifically proteins (and encrypted bioactive peptide sequences) and phenolic substances We isolated and characterized peptides and phenolic compounds from BSG and assessed their potential bioactivities in human cells. Cytomodulatory activities are quantified using biomarkers for antioxidant, immunomodulatory, anticancer, anti-atherogenic and cholesterol lowering capability in different cell lines. In a series of experiments completed we have assessed the ability of phenolic-rich BSG extracts to protect against oxidant-induced DNA damage in human lymphocytic U937 cells. DNA damage was assessed using the comet assay and the oxidants employed were H2O2, SIN-1, 4-NQO and t-BOOH. The phenolic extracts of BSG protected against the genotoxic effects of H2O2 and SIN-1, but not against 4-NQO and t-BOOH. Results suggest phenolic extracts may possibly be chelating iron and/or scavenging reactive oxygen species (ROS). Similar studies are ongoing with respect to evaluating the antioxidant potential of protein and peptide-rich fractions of BSG. Results to-date provide valuable information on the potential of BSG to be exploited as a source of bioactive ingredients.

Bone Growth Promoting Bioactive Peptides (Bonepep) from Egg Yolk. Mujo Kim¹, Kazuhito Takeshima¹, Kenji Horie¹, Tetsuro Yamane², ¹Pharma Foods International Co., Ltd., Japan, ²Matsushita Memorial Hospital, Japan

The egg is a complete nutritional food with the high nutritional value extremely in food. Hen egg hatch into chick after warming for 21 days. It means that hen egg contains every integrant element to compose a life. We focused on one particular element of hen egg that makes up for bones and developed hen egg yolk derived food ingredient "Bonepep" for bone-metabolism improvement. Bone normally is brought a balance between bone formulation and absorption by osteoblast and osteoclast. It constantly keeps a certain amount of bone mass to break old bone, and create new bone. The effect of Bonepepon bone metabolism was studied with growing rats. One study to see the effect of Bonepep on bone formulation confirmed that oral ingestion of Bonepep significantly promoted an elongation rate of tibiae among rats. Furthermore, another study with ovariectomized mouse (OVX), as a model of postmenopausal osteoporosis, to verify the inhibitory effect of bone absorption showed that oral ingestion of Bonepepsignificantly inhibited loss of bone density among OVX.

Therapeutic Potential of Novel Bioactive Peptides from Honey. Hisham R. Ibrahim, Faculty of Agriculture, Kagoshima University, Kagoshima, Japan

A substantial part of honey is made of proteins, which form about 30-50% of the dry mass. The major honey proteins belong to a larger family based on Major Royal Jelly Proteins (MRJPs), of which nine members with molecular masses in the range of 49-87 kDa have been identified. These MRJPs do not have any relatives in other non-insect metazoan species and is generally accepted that they play a role as a source of essential amino acids in the nutrition of honeybee larvae. However, there has not been any evidence provided for the bio-activities of honey proteins or their peptides. For therapeutic and nutraceutical applications, it remains to be explored whether these proteins and their gastrointenstinal digests, i.e. peptides, exert physiological role in protection or treatment of human diseases. This study demonstrates, for the first time, that gastrointestinal digestion simulation liberates bio-active peptides encrypted into honey proteins. Specifically, this work will explore novel bio-active peptides of honey proteins, which heralding a fascinating opportunity for its potential candidacy as anti-oxidative therapeutic peptides for the treatment and risk reduction of emerging oxidative stress related diseases.

AFTERNOON

PCP 3 Bioactive Food Proteins and Peptides II - Applications

Chair(s): N.S. Hettiarachchy, University of Arkansas, USA; and P. Kerr, Solae LLC, USA

New Separation Technology leads to Sustainable and Economical New Soy Proteins. K. Keller, R. Konduru, B. Pierce, S. Stahl, E. Ersen, Solae-DuPont, St. Louis, MO, USA

Do you know that, on average, the CO2 emissions from your car are of the same order of magnitude as that of the food you consume? Food production has attracted attention from the global community due to its demand for large amounts of energy and natural resources. When evaluating the environmental impact of various foods, soy protein is a sustainable solution. The industrial production process of soy proteins was introduced more than 50 years ago and soy proteins are produced in hundreds of thousands of tons by Solae. After oil extraction from the soybeans, the residual white flakes contain fibers, proteins, sugars and minerals. The soy proteins are extracted from white flakes using water and the fibers are removed using solid bowl centrifuges. Isoelectric precipitation is used to purify proteins from the extract. To further improve quality and reduce the environmental footprint of this process, new separation processes are being considered to produce new soy proteins. One option is to use combinations of membrane technology to increase yield and improve quality. To separate specific proteins, chromatographic technology is a common process to generate new ingredients. In-process water recycling will play a critical role in the future. This presentation will provide an overview of new soy products generated by unique separation technology.

Production and Efficacy Testing of Plant Protein-derived Antihypertensive Protein Hydrolysates and Peptides. Rotimi Aluko, University of Manitoba, Winnipeg, MB, Canada

Plant proteins are cheap sources of raw materials for the production of bioactive peptides, especially antihypertensive peptides that can be used to formulate functional foods and nutraceuticals. This presentation focuses on antihypertensive peptides produced from yellow field pea, flax and hemp seed proteins. A pea protein hydrolysate (PPH) was produced by thermolysin digest of pea protein isolate (PPI) followed by ultrafiltration through a 3 kDa molecular weight cut-off (MWCO) membrane. The PPH showed in vitro inhibitions of renin and angiotensin converting enzyme (ACE) activities with subsequent lowering of blood pressure (BP) after oral administration to spontaneously hypertensive rats (SHR). In contrast the unhydrolyzed PPI had no antihypertensive effect in SHR. Hemp seed protein hydrolysate (HPH) and flaxseed protein hydrolysate (FPH) were also effective BP-lowering agents when administered orally to SHR. Fractionation of the HPH and FPH into peptides of smaller sizes resulted in significant (p<0.05) losses in BP reducing effects. The PPH also lowered BP when fed as a component of the diet to Han:SPRD-cy rat (a model of chronic kidney disease) over an 8-week period. Plasma level of angiotensin II (vasopressor) was reduced in rats fed PPH, which correlated with observed BP reduction.

Peptides Derived from Soybean Flour Bear Anti-cancer Activity against Kasumi-3 Blood Cancer Cells. S. Rayaprolu, N. Hettiarachchy, A. Kannan, P. Chen, University of Arkansas, Fayetteville, AR, USA

Soy flour obtained from high oleic acid soybeans is an inexpensive source of high quality protein. The purpose of this research was to add value to soybean flour by utilizing proteins from the flour and generating bioactive peptides. Specific tasks included the extraction of proteins from the flour, hydrolyzing proteins to peptides, making peptides resistant to simulated gastro-intestinal (GI) environment, and fractionation to obtain GI-resistant fractions. The fractions (<5, 5-10 and 10-50kDa) were tested for anti-cancer activity by the MTS cytotoxicity assay on human cancer cell lines. Our research demonstrated in vitro anticancer activity of peptide fractions against human breast (MCF-7), colon (HCT-116, Caco-2), liver (HepG-2), prostate (PC-3) and lung (NCL- H1299) cancer cells. Further screening included Kasumi-3 (acute myeloblastic leukemia) human blood cancer cell line. The 10-50kDa peptide fractions from the high oleic acid soybean line N98-4445A inhibited 63% of the Ksumi-3 blood cancer cells while the 5-10kDa fractions from high oleic acid soybean line S03-543CR caused approximately 57% inhibition on the Kasumi-3 blood cancer cells. The research demonstrated the use of an economic co-product from the soybean oil industry to derive nutraceuticals in the form of bioactive peptides that may play a role in cancer prevention and therapy.

Anti-inflammatory Peptide, Pyroglutamyl-leucine - Distribution in Fermented Foods. K. Sato, T. Kiyono, E.Y. Park, Y. Nakamura, Kyoto Prefectural University, Kyoto, Japan

Pyroglutamyl-leucine (pEL) was isolated from wheat gluten hydrolysate and has been demonstrated to suppress inflammation in vitro and in vivo systems. Pyroglutamyl residue can be formed from amino terminal glutaminyl residue in water. Then the pEL could be derived from QL during processing. Our previous studies have demonstrated wide distribution of pyroglutamyl peptides in protein hydrolysate. Production of peptide also occurs in fermentation process of food. However. There is limited information on pyroglutamyl peptides in fermented food. In the present study, we demonstrate occurrence of anti-inflamatory peptide pEL in various fermented foods; fermented soy and milk, and alcoholic beverages. Especially in Japanese rice wine, it accounts for approximately 25% of total amino-terminal blocked peptide fraction. The alcohol-free fraction of Japanese rice wine moderate DSS-induced colitis on rat colon. These facts suggest anti-inflamatory functional food could be prepared by using fermentation technology involved in Japanese rice wine production.

Growth Performance and Health Characteristics of Broiler Chickens Fed with Cottonseed Proteins and Peptides. Aike Li, Xiaolin Zhang, Liangwei Qiu, Tingting Yun, Fei Han, Jing Xu, Yingyao Wang, Hui Lu, Academy of the State Administration of Grain, Beijing,P. R. of China

Cottonseed proteins and peptides (CSPP) which were made mainly from cottonseed meal (CSM) through fermentation and/or enzymatic hydrolysis were studied for bioactive compositions and animal feeding effect . The crude protein content in CSPP was about 59% , roughly 10% true protein net increase after treatments. The small peptides (<600Da) content increased from original 3.82% to 18.72%. The relative distribution of small peptides released from CSPP in various parts of chicken digestive tract were higher than those from several protein feedstuffs. Free gossypol in CSPP was degraded with detoxification ratio of 78.06% . For feeding experiment, 180 broilers, 21-day-old, were randomly divided into 6 treatments with 6 replicates of 5 birds each, and fed 6 diets containing equal digestible nutrients with a different protein feedstuff for 21 days. The two control treatments contained 34% SBM and 34% CSM, respectively. The other treatments had CSPP ranged from 17% to 34%. CSPP significantly improved the average daily gain, feed intake and feed conversion rate (P < 0.05). The thymus index,spleen index and Fabricius index were significantly improved (P < 0.05) also. The intestinal flora diversity, blood biochemical parameters and antioxidant function of the trial broilers fed diets containing CSPP were also improved.

Antibiotic Function of Saccharicterpenin Extracted from Camellia oleifera Seeds in Broiler Chickens. Aike Li, Yingyao Wang, Tingting Yun, YongXin Zhao, Fei Han, Yijiang Hou, Xia Luan, Academy of the State Administration of Grain,, Beijing, P. R. of China

Saccharicterpenin in the Camellia oleifera seeds is a feed-additive as an antibiotics alternative in China. Aqueous enzymatic extraction technology was adopted to extract the oil and saccharicterpenin from kernels simultaneously. The recovery rate of saccharicterpenin from the kernel is 80%, and the triterpenoid saponin content of saccharicterpenin is more than 30%.180 broilers,1-day-old, were randomly allocated into 5 dietary treatments with 6 replicates of 6 birds each. The controlled group was fed with corn-soybean basal diet with antibiotic,20ppm virgianmycin. The other groups were fed with the same basal diet containing different doses of saccharicterpenin. The treatments were no significant different in the average daily gain (ADG), feed intakes, feed conversion rate (F/G)and immune organ indexes (P<0.05). However, the group containing 600 ppm Saccharicterpenin had the best ADG, F/G , dressing percentage and full bore rate. The immune and antioxidant functions, intestinal flora, blood biochemical parameters and the meat quality of broilers were investigated, and a challenged trial was also carried out in order to study the effect of Saccharicterpenin by aqueous enzymatic extraction to replace the antibiotics on broilers diet.

PCP 3.1 Protein Structure and Functionality in Food and Non-Food Applications

Chair(s): J. Wu, University of Alberta, Canada; and N. Shah, Solae LLC, USA

Bowman-Birk Inhibitor; Purification and Preclinical Efficacy in Neuromuscular Disease. C. Schasteen, J. Wu, B. Pierce, B. Tulk, P. Ghosh, M. Mekel, Solae LLC, Saint Louis, MO, USA

Soy has been consumed safely for many hundreds if not thousands of years by millions of humans. Several protease inhibitors, Bowman-Birk and Kunitz, most commonly referred to as trypsin inhibitors BBI and KTI, respectively, are the best known and the most studied biologically active proteins in soybean. KTI is the acknowledged antinutrient and is inactivated using heat, e.g., the toasting of soybean flakes. BBI is not an antinutritive, is heat stable and has been reported in the literature to possess diverse bioactivities including anticancer, anti-inflammatory, positive effects in neuromuscular disease, ulcerative colitis, radiation-induced transformation in vitro and a decrease in the photoaging of skin. We have purified soybean BBI to homogeneity using a variety of separation techniques. The molecular targets for the variety of bioactivities noted above for BBI are not completely understood, however, proteases are involved in a multitude of physiological cascades and the potential of BBI to control these pivotal proteases is logical. Examples of the different animal models of neuromuscular disease will be presented where BBIC or BBI have been evaluated

Protein-lipid Interactions and Their Effect on the Quality of Soy Protein Isolates. Naina Shah, Anthony Irwin, Phil Kerr, Solae, USA

Proteins produced using High Oleic soybeans were observed to have functional advantages like increase whiteness index and low viscosity. However the molecular basis of these functional benefits was not well understood. Here we present a systematic study of protein lipid interactions and their effect on the functional properties of the proteins. Isolates were generated and the composition of the lipids in the isolates were varied either by fatty acid addition or by mixing of 2 flakes with inherently different fatty acid compositions. The resultant isolates were evaluated for viscosity and whiteness, both properties were related to the amount of un-saturated fatty acids in the flake, either inherent or added.

Industrial Applications of Functionalized Soy Storage Proteins. Richard E. Gagnon, Peter Baele, Keith B. Cockerline, DuPont Soy Polymers, St. Louis, MO, USA

Soy storage proteins may be functionalized for industrial use through physical and chemical processes. In this presentation, the authors will discuss industrial applications of functionalized soy proteins and draw clear distinctions between these materials and soy proteins isolated as food. The presentation will emphasize the relationship between functionalized soy protein characteristics and both downstream processing and the desired attributes of finished consumer goods.

Structure-function Study of Major Crucifer Oilseed Storage Protein: Emulsifying Properties and Hydrophobicity of Homomeric Cruciferin. T.S. Withana-Gamage^1,2, D.D. Hegedus^1,2, X. Qui², J.P.D. Wanasundara^1,2, ¹Agriculture and Agri-Food Canada, Saskatoon SK S7N 0X2, Canada, ²Department of Food and Bioproduct Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5A9, Canada

Cruciferin is the predominant 11S globulin of crucifers such as canola and mustard and has tremendous potential as a food or non-food protein. This hexameric protein is composed of subunits expressed by few different genes. The heterogeneity of subunit composition is reflected in the structural and physico-chemical properties of a protein. Using Arabidopsis mutant lines (homomeric Cru A, Cru B, or Cru C), emulsifying properties and hydrophobicity were studied and compared with wild type counterpart. The surface hydrophobicity of all protein isoforms was related to the emulsifying properties which were evaluated using visual, static light scattering, and confocal laser scanning microscopy. For each of these properties, Cru C exhibited clear separation from other two types of cruciferin isoforms. Three-dimensional structures of cruciferin homotrimers obtained through comparative modelling showed significant differences in the structural properties of CruC proteins because of the extended loop segments and their residue composition. This relationship of experimental data with modelling predictions, show the strength of in-silico assessment of structure related physicochemical properties to predict functional properties of cruciferins.

Corn Protein Blends, Part 2 – Thermal Properties and Morphology. C.J.R. Verbeek¹, K.A. Rosentrater², ¹University of Waikato, Hamilton, New Zealand, ²Iowa State University, Ames, Iowa, USA

As a result of the growing biofuel industry, by-products such as high protein corn gluten meal (CGM) and fibre rich dried distillers grain with solubles (DDGS) has also grown. CGM has been shown to be suitable as a biopolymer, while DDGS’s high fibre content made it less attractive despite it being considerably cheaper. In this study extrusion behavior of CGM and DDGS blends were evaluated, using urea as a denaturant. DDGS:CGM in ratios 0,33,50,66 and 100% were examined using a single screw extruder relying entirely on dissipative heating. Replacing CGM with DDGS had no adverse effect on power requirements for extrusion, although blends containing DDGS were less uniformly consolidated and also resulted in more dissipative heating. Blends showed multiple glass transitions, characteristic of mechanically compatible blends. Transmission electron microscopy revealed phase separation on a micro-scale, although distinct CGM or DDGS phases could not be identified. On a macro-scale, optical microscopy suggested that CGM rich blends were better consolidated, supported by observations of a more continuous extrudate forming during extrusion. Future work should aim to also characterize the mechanical properties of these blends to assess their suitability as either bioplastic feedstock or pelletized livestock feed.

Plastic from Feather Quills. Jianping Wu, Aman Ullah, University of Alberta, Edmonton, Alberta, Canada

Feather is a waste product of the poultry industry. The purpose of the study is to develop plastic from feathers. The effect of four different plasticizers on the thermoplastic properties was then investigated. Conformational changes and plasticizer-protein interactions in the extruded resins were assessed by FTIR, while viscoelastic behaviour of the quill keratin plasticized with different plasticizers was investigated by dynamic mechanical analysis (DMA). DSC was used to determine the effect of different plasticizers on protein denaturation. Thermal degradation patterns of the extrudates were studied by thermogravimetric analysis (TGA). The effect of plasticizers on the mechanical properties of resins was also assessed by tensile strength measurements. Results indicated that ethylene glycol was able to interact more effectively with quill keratin at the molecular level, exhibiting only one sharp glass transition, better mechanical properties, and higher transparency compared to other plasticized resins. The two phases found in glycerol plasticized material were attributed to glycerol-rich and protein-rich zones. Propylene glycol and diethyl tartrate exhibited lower H-bonding interactions and showed wide transition regions in DMA profiles during heating, suggesting weak and heterogeneous interactions between quill keratin and these plasticizers.

WEDNESDAY

MORNING

ANA 4.1/PCP 4: Practical Methods for Assessing By-Product Quality

Chair(s): B. Musselman, IonSense, USA; and L. Reimann, Eurofins Scientific Inc., USA

Pyrolysis GCMS and GCMS of Pyrolysis Oil, Powerful Analytical Techniques in Bio-Mass to Gasoline Conversion Research. M.T. Cheng, Chevron, Richmond, CA, USA

It has been published that US yard waste, when converted to transportation fuel, can supply about one-third of US gasoline needs. Yard waste is composed mainly of cellulose and lignins, both highly oxygenated, and polymeric in structure. To satisfy the octane as well as the energy density requirement of modern passenger vehicle, it is necessary to remove these oxygen atoms, as well as converting to compounds of much lower in molecular weight. Pyrolysis of bio-mass is easily executed, and it can possibly generate compounds in the desirable carbon number range for gasoline. In this report, the analysis of pyrolysis oil, and the use of pyrolysis GCMS will be discussed with the perspective of gasoline manufacturing.

Development of a Simple and Green Analytical Method for Determination of Acid Number of Biodiesel and Biodiesel Blends using Green Chemistry Approaches. A. Baig¹, M.D. Paszti², F.T.T. Ng¹, ¹Department of Chemical Engineering, University of Waterloo, Waterloo, Ontario, Canada, ²Rothsay, a Division of Maple Leaf Foods Inc., Guelph, Ontario, Canada

Biodiesel has gained importance throughout the world which has resulted in a significant increase in the commercial use of biodiesel and biodiesel blends. Therefore, various quality standards such as ASTM D 6751 and EN 14214 included the acid number (AN) as an important quality parameter. Currently, alternative inexpensive feedstocks with high FFA content are gaining momentum around the world. This requires an accurate determination of AN to monitor the progress of the biodiesel production process. ASTM D 664 has major problems such as mediocre reproducibility, tedious process for cleaning electrodes, relatively long analysis time, large sample size and use of excess toxic solvents as well as it generates large amount of hazardous waste which is highly undesirable. This becomes critical for today′s commercial production processes where time-efficient, cost-effective, and environmentally green analytical methods are essential for meeting the quality standards. Therefore, a new analytical method based on green chemistry approaches, has been developed. This proposed green analytical method could be used for the determination of AN of biodiesel and biodiesel blends in R&D and industrial quality control laboratories as a simple, time-efficient, cost effective,and environmentally friendly method.

A Simple, One-step, Quantitative Analytical Method for the Analysis of Fatty Acids in Natural Products. R. Freeman¹, T. Yuzawa², C. Watanabe², T. Ramus³, ¹Frontier US, Antioch, CA, USA, ²Frontier Laboratories, Koriyama, Fukishima, Japan, ³Diablo Analytical, Antioch, CA, USA

Precise fatty acid profiling is an essential step in the characterization of natural products including many food stuffs, supplements, biomass processes and clinical diagnostic tests. Because fatty acids are thermally unstable, they are converted to methyl esters prior to analysis. The most common method for derivatizing the acids utilizes BF3; however, BF3 is toxic, is noted for its instability and is not universally available. This work describes, in detail, a simple, automated method for profiling fatty acids in a complex matrix. The new method is based on reactive pyrolysis (RxPY)-GC which is, actually, thermally assisted hydrolysis and methylation. Microgram quantities of the "untreated" sample and a few μL of an organic alkali are placed in a small sample cup. When heated, FAMEs are formed and separated by GC.The results of a recent validation study serve as the basis of this report. The impact of (1) using TMAH, TMSH & m-TFPTAH, (2) the reaction temperature (3) and the reagent concentration on the degree of isomerization will be presented. The analysis of C22:6, C20:4 and C6:0 will be used to compare the BF3 and PxPY methods. Analytical precision is on the order of 1-2 %RSD. Quantitative results, based on both standard addition and external standard techniques, will be reported.

The Effect of Pea Protein on Physicochemical Characterization and Oxidative Kinetics of Rapeseed Oil Nanoemulsions. Elmira Arab Tehrany, Eugène Mallo, Nabila Belhaj, Behnoush Maherani, Michel Linder, Nancy Université, Nancy, France

The rapeseed oil is one of the most important sources of mono unsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA). The susceptibility of PUFAs to oxidation increases because of their degree of unsaturation. The present study focused primarily on the preparation and characterization of different formulations of nanoemulsions composed of rapeseed oil and pea protein by high-pressure homogenization. The oxidative stability of samples was closely monitored by infrared spectroscopy and gas chromatography. The particle sizes and electrophoretic mobility of different nanoemulsions stabilized by pea protein were measured by dynamic light scattering. We measured viscosity, crystallization and melting point by differential scanning calorimeter and retention of aromas compounds by pea protein with CPG-Head Space of each nanoemulsion. The results showed that pea protein protects the rapeseed oil from oxidation phenomena during 2 months and improves the sensorial quality of nanoemulsions by retaining some aroma compounds like as n-decane. We observed that the stability and the size of nanoemulsions varied by adding the pea protein at different concentrations. We can conclude that pea protein has an important influence on physico-chemical and sensorial properties of rapeseed oil.

High Throughput Screening of Flax Peptides and Lignans. C. Olivia¹, P.-G. Burnett², D. Okinyo-Owiti², M. Bagonluri², M. Reaney², ¹Department of Food and Bioproduct Sciences, University of Saskatchewan, Saskatoon, SK, Canada, ²Department of Plant Sciences, University of Saskatchewan, Saskatoon, SK, Canada

The Flaxseed World Core Collection is consisted of 380 accessions that represent a wide variation of flax gene resources. This collection, grown at Saskatoon, SK and Morden, MB in 2009 was screened for cyclolinopeptide (CLP) and lignan (secoisolariciresinol diglucoside - SDG). Cyclolinopeptides are cyclic hydrophobic peptides containing eight to ten amino acid residues with molecular weights of approximately 1kDa. Both CLPs and SDG have been identified as biologically active compounds. In order to determine genetic variation in both CLP and SDG fractions of the collection, the extracts were analyzed by reverse phase HPLC using UV detection at 214 nm and 270 nm. The identity of eluting peaks was confirmed by comparison of retention time and UV spectra with those of authentic CLP and SDG standards. Two novels CLP, found in cultivar TMP 2181 were subjected to LC-MS/MS for molecular weight and sequence identification. Cyclolinopeptides and SDG profiling data will be presented and discussed.

Atmospheric Pressure Photoionization (APPI) for LC-MS Analysis of Lipids—An Overview. Sheng-Suan Cai, Syagen Technology, Inc., Tustin, CA, USA

ESI has been the most widely used ionizer for LC-MS analysis of lipids. However, due to the wide structural diversity of lipids, the most nonpolar part of the lipidome is often detected with low sensitivity by ESI. One of the strengths of APPI is its ability to simultaneously ionize both polar and nonpolar lipids with high sensitivity. In addition, APPI has been shown to give high sensitivity under both aqueous reversed phase and non-aqueous reversed phase or normal phase LC conditions. Therefore APPI can be a better ionizer for simultaneously LC-MS analysis of both polar and nonpolar lipids. APPI has been used for analysis polar and nonpolar sterols and oxysterols, water and fat soluble vitamins (i.e. A, D, K), fatty acids and esters, acylglycerols, phospholipids (e.g., phosphatidylcholines, phosphatidylethanolamines, phosphatidylserines, phosphatidylglycerols, phosphatidylinositols and phosphatidic acids), sphingolipids (e.g., ceramides, cerebrosides, galactocerebrosides, sphingomyelin, sulfatides), and triterpenes (e.g., squalene), etc. In this presentation, I will give a comprehensive overview of APPI analysis of various classes of lipids, together with APPI ionization mechanisms and how to maximize APPI sensitivity such as dopant selections and mobile phase optimizations.

FAME Analysis Utilizing the Unique Selectivity of Ionic Liquid Capillary Columns. L. Sidisky, G. Baney, J. Desorcie, K. Stenerson, D. Shollenberger, Supelco, Bellefonte, PA, USA

Analyses of fatty acid methyl esters (FAMEs) are continuing to gain importance as more research is focusing on their biomedical impacts. This includes the analysis of saturated and polyunsaturated FAMEs along with the positional geometric (cis and trans) FAME isomers. Traditionally, FAME analyses have been performed using silicone polymer or polyethylene glycol based stationary phases that yield typical elution patterns. Analysts performing the task of analyzing the fatty acid composition of food have a wide variety of capillary column selectivities available for resolving the fatty acids as FAMEs depending upon the information they require from their analyses. Traditional nonpolar methyl silicone columns, polar polyethylene glycol columns and highly polar cyanosilicone columns have all been used to provide FAME resolution. A new class of stationary phases based on Ionic Liquid technology has now been developed and have been demonstrated to provide unique elution patterns for FAME isomers compared to the traditional silicone or polyethylene glycol based stationary phases. We will compare and contrast the selectivity of the ionic liquid phases with the polymeric based phases using Rapeseed Oil FAMEs.

Rapeseed Protein Extraction and Application. Frank Pudel¹, Ralf-Peter Tressel¹, Klaus Düring², ¹Pilot Pflanzenöltechnologie Magdeburg e.V., Magdeburg, Germany, ²Axara Consulting, Frechen, Germany

Rapeseed proteins besides their high nutritional value possess promising functional properties. They enable stabilization of emulsions and foams as well as formation of gel-like and other structured systems with high water binding capacity. Therefore, a lot of new higher value applications in human nutrition, animal feeding and for different technical purposes are envisaged. Numerous descriptions of technologies for processing of rapeseed proteins are found in the literature. However, there are only few commercial applications. Rapeseed contains two protein fractions in similar amounts: napin and cruciferin. These proteins have different solubility properties. Therefore, protein extraction has to be more sophisticated to extract both almost quantitatively. Additionally, rapeseed contains some characteristic secondary plant substances which interact with the proteins and negatively influence both their nutritional value and their functional properties. Finally, protein yield and functionality are strongly dependent on the process steps applied before protein extraction. The presentation will describe solutions for rapeseed protein extraction and purification technologies, among them a new EBA IEX process which leads to extremely pure individual napin and cruciferin proteins. Furthermore, results of application tests in aquaculture and in the paper industry will be presented.

Algal Polar Lipids Quantification by HPLC. J.A. Gerde, L. Yao, T. Wang, Dept. of Food Science and Human Nutrition Iowa State University, Ames, Iowa, USA

High performance liquid chromatography with evaporative light scattering detection was used to characterize and quantify all polar lipid species in Chlamydomonas reinhardtii, Scenedesmus spp., Nannochloropsis spp., and Schizochytrium limacinum microalgae. Baseline separation of the polar lipids species (glycosyl sterols, monogalactosyl glycerides, digalactosyl glycerides, and individual phospholipids) was achieved and the peaks were confirmed by mass spectroscopy.

Determination of Diacylglycerol Isomers in Vegetable Oils Gas Chromatography - Mass Spectrometry. H. Zhu, S. Wang, M. Clegg, C. Shoemaker, University of California Davis, Davis, CA, USA

The verification of authenticity of extra virgin olive oil has been an international problem. A new standard has been proposed relate to the ratio of 1, 2- diacylglycerol (DAG) to 1, 3- DAG. The identification of peaks has been a significant problem in the GC analysis of DAG isomers in vegetable oils. In this study, gas chromatogram -mass spectrometry (GC- MS) methods were developed to identify DAG isomers present in vegetable oils. DAGs were isolated as polar fractions from oil samples by solid- phase extraction (SPE), and then the silyl derivatives were separated by GC on a low polarity phase column, which allowed for the separation of DAGs according to their molecular weight and chemical structure. Both electronic ionization and acetonitrile chemical ionization methods were employed as ion sources to provide information about the isomeric structure and molecular weight of DAGs. By using this method, twelve species of DAGs were determined in olive oil, grape seed oil and cocoa butter. In addition, three silylation reagents, diol- phase and silica gel SPE columns were tested of their selectivity and recovery rate of DAG isomers to improve the preparation method. The properties of dilaurin and diplamtin as internal standards were compared by their response rates of to diolein and distearin, which were the main DAGs in olive oil and cocoa butter.

Algal Biomass Constituent Analysis: Method Uncertainties and Investigation of Underlying Measuring Chemistries. L.M.L. Laurens¹, T.A. Dempster³, H.D.T. Jones², ¹National Renewable Energy Laboratory, Golden, Colorado, USA, ²Sandia National Laboratories, Albuquerque, New Mexico, USA, ³Arizona Center for Algae Technology and Innovation, Mesa, Arizona, USA

Algal biomass composition forms the basis of a large number of techno-economic process analysis models and is used to investigate and compare different processes in algal biofuels production. Throughout the Sustainable Algal Biofuels Consortium (SABC), a consistent analysis of the biomass constituents is necessary to score progress and conversion efficiency. Classical analysis techniques are based on empirical methods that have been in the literature for sometimes over 50 years and have not been refined much or applied to a range of different algal strains. For example, no universal lipid quantification procedure is currently available in the literature. We present data on the robustness of methods for lipids, protein, carbohydrates, ash and moisture of algal biomass, across three institutions, 6 independent researchers and over 12 days. This data set shows interesting trends with regards to the uncertainty associated with each of the methods and revealed significant differences between different approaches to measuring protein, starch and lipids. We present the results with associated statistics pointing to significant differences between laboratories but not within one laboratory. We discuss the underlying measuring chemistries of the lipid, protein and carbohydrate quantification procedures.

AFTERNOON

PCP 5: General Protein and Co-Products

Chair(s): N. Deak, Solae LLC, USA; and S. Jung, Iowa State University, USA

Incorporation of Soybean Aqueous Extraction Co-products to Dry-grind Corn Ethanol Fermentation. L. Yao, S.-L. Lee, T. Wang, J.M.L.N. de Moura, L.A. Johnson, Department of Food Science and Human Nutrition, Iowa State University, Ames, IA, USA

The feasibility of using soy skim, a protein-rich liquid co-product from soybean aqueous extraction processing, in dry-grind corn fermentation for fuel ethanol production was evaluated. First, in a simple glucose-supplied media soy skim was a good source of nitrogen and minor nutrients, which supported normal yeast growth. Then effects of skim addition level, corn particle size, water-to-solids ratio, and addition of urea on corn-soy co-fermentation were determined on 0.5 L scale. The addition of skim increased fermentation rate by 10 to 28% and thus shortened the fermentation time without affecting ethanol yield. When 100% of water was replaced with soy skim, the addition of urea was unnecessary. Corn of smaller particle size or higher water-to-solids ratio in the mash resulted in higher fermentation rate but did not increase ethanol yield. Solid and protein contents in the finished beer increased with the addition of soy skim. The 100% skim addition resulted in soy enhanced DDGS with 47% protein (dwb) containing 3.6% lysine.

Ultrasound-assisted Extraction of Flaxseed Gum. J.F. Fabre, E. Lacroux, G. Vaca-Medina, Z. Mouloungui, Université de Toulouse- UMR1010 Chimie Agro-Industrielle, ENSIACET, INPT, INRA, 4 allée Emile Monso, 31030 Toulouse, Toulouse, France

An integrated process has been developed to extract oil and other valuable compounds from oleoproteaginous seeds through different steps beginning with an aqueous crushing. Processing flaxseeds in water is difficult due to their high gum, mucilage content. Different extraction protocols were applied to extract this mucilage.Seeds were immersed in water and underwent several physical or chemical methods. pH variation and microwaves don't have measurable effect whereas stirring mode has a slight influence. Ultrasound technology appeared to be the best method to totally extract this mucilage without organic solvent. The amplitude and time of application of ultrasound waves were optimized to get a quick release of mucilage with a stable and low temperature to avoid protein denaturation. The influence of this treatment on the composition and physical properties of the mucilage was determined. It can then be conditioned as a freeze-dried solid.The nature and rheological behavior of the polysaccharides extracted allow multiple applications in cosmetic or pharmaceutical formulations. The mucilage-free seeds will now be more easily characterized and further processed to recover both an oil-rich and a protein-rich fraction.

Study on Different Components' Functional Properties in vitro of Rapeseed Protein Hydrolysate. Yingyao Wang, Zhangqun Duan, Xia Luan, Rong Ma, Cuiping Wei, Academy of State Administration of Grain

Aqueous enzymatic extraction (AEE) is a safe and efficient vegetable-oil extraction process that may also result in edible protein hydrolysates. It is one of the benefits of AEE processing that obtaining the oil and protein product simultaneously. In this presentation, the composition, antioxidant activity in vitro and inhibition of ACE activity of rapeseed protein hydrolysates (RPH) which were the co-products of AEE processing from rapeseed were analysized. Then the protein hydrolysates were separated by gel filtration chromatography into different components. The relationship of antioxidant activity in vitro and inhibition of ACE activity of different components between the amino acid composition and the molecular weight distribution of the components were discussed. The result shows the protein hydrolysates have good functional properties in vitro. There are nine peaks after separated by Sephadex G-25 and peak 2, peak 4 and peak 5 which contains higher levels of hydrophobic amino acids have better functional properties in vitro and more than 90% of the molecular weight distribution in which is lower than 1000.

Integrated Process and Whole Flaxseed Emulsions Obtaining. E. Lacroux, J.F. Fabre, G. Vaca Medina, Z. Mouloungui, Université de Toulouse - UMR1010 Chimie Agro-Industrielle, ENSIACET, INPT, INRA, 4 allée Emile Monso, 31030 Toulouse, Toulouse, France

Research and development on the removal of mucilaginous polysaccharides from flaxseeds allowed testing a previously developed integrated process on such a raw material.The integrated process is a green way to fractionate all the compounds, and especially lipids, from a whole oleaginous seed. This process was first developed in order to extract lipids from seeds without organic solvent. Beyond research on valuable oil phase, all other fractions coming from seeds processing were investigated as protein-rich or fiber-rich phases.Flaxseeds were processed after mucilage extraction. Physical treatments in aqueous medium give oil-rich, protein-rich and fiber-rich fractions. Chemical properties and composition of each fraction were determined. Furthermore, as the most valuable fraction, emulsified lipid phase was characterized for physical and rheological properties.All the properties and composition of these fractions obtained by integrated process were compared between spring and winter varieties of flaxseeds.Industrial uses and applications of developed products can be targeted according to major components and to rheological behavior of each fraction.

Isolation and Characterization of Starch from Defatted Cashew Nut Shell. Maria Yuliana, Yi-Hsu Ju, National Taiwan University of Science and Technology, Taipei, Taiwan

The use of fossil fuels such as naphtha and natural gas for producing plastic resins accounts for about 4 to 5% of the world’s oil consumption, with the increasing demand in the future. A challenge comes from the society to reduce the exploitation of fossil fuel and to preserve the environment from the harmful effects of the indiscriminate plastic disposal. Starch attracts public attention as a replacement of fossil fuel in polymer industries because it is renewable, biodegradable and nontoxic. In this study, starch was purified from defatted cashew nut shell (CNS) by using wet milling. A product that contains 85.01 wt.% starch was recovered from the defatted CNS. Various analyses were performed on the starch to characterize its physicochemical properties. The feasibility of this starch as a renewable material for commercial application such as starch-based bioplastic production was also observed. It was found that the starch obtained possesses high amylopectin content (75.35 wt.%). Morphological study of the starch showed that the grains are irregular in shape with rough surface. Bonded resins were found attached to the starch granules.

Wood Adhesive from a Protein-polymer Conjugate: Characteristics and Optimization. Chanchan Wang, Jianping Wu, University of Alberta, Edmonton, Alberta, Canada

A novel and simple method to modified canola cruciferin protein by grafting reaction was developed. Our challenge was to modify canola protein into high performance adhesive, extensively used in the wood industry. In this way, cruciferin protein, bearing glycidyl methacrylate (GMA) covalently bounded to a side chain of protein, were synthesized. Fourier transformaed infrared spectra, was performed to verify the grafting of the GMA, and analyzed the structure change of the protein. Differential scanning calorimetry was used to determine the effect of grafted GMA on protein denaturation and structure change. Thermogravimetric analysis was used to investigate the thermal stability of the modified protein. And the adhesive properties of modified protien were compared to native cruciferin protien. Results indicated that the hydrogen bonding in cruciferin molecular was interrupted by grafting polymer, while the stability of the modified protein was improved. The modified protein showed better adhesion strength and relatively higher water resistance.

Isolation and Applications of Modified Flax Peptides. P.D. Jadhav¹, D.P. Okinyo-Owiti², J. Shen², P.G. Burnett², M.J.T. Reaney², ¹Department of Food and Bioproduct Sciences, University of Saskatchewan, Saskatoon, SK, Canada, ²Department of Plant Sciences, University of Saskatchewan, Saskatoon, SK, Canada

Flax seed oil (Linum usitatisssimum) contains hydrophobic cyclic peptides or cyclolinopeptides (CLPs) comprising eight to ten amino acids. To date, eleven cyclolinopeptides (CLP-A to K), having molecular weights of approximately 1kDa have been reported. The CLPs (A, C, and E) have immunosuppressant activity and induce apoptosis in nematodes and a cancer cell line. Cyclolinopeptides are thus bioactive compounds with potential for use as therapeutics. The current research required the isolation of peptides from flax oil in multigram quantities. Making specific changes to the methionine or methionine sulfoxide group in a systematic fashion, without changing other amino acids produced novel and useful peptide analogs. Specifically synthetic methods were devised to introduce different activating functional groups such as CN, -COOH, -OH and -NH2 to the sulfur atom of methionine. The cyclic peptides were systematically linked to molecules or materials of interest including fluorescence tags, affinity chromatography media and serum albumin (for production of polyclonal antibodies). These modified peptides are shown to be good candidates in these applications. In addition, these peptides were completely characterized using spectrometric techniques including 1D and 2D NMR spectrometry, as well as mass spectrometry. Complete synthesis and various applications of flax peptides will be discussed.

Protein and Co-Products Posters

Chair(s): J. Wu, University of Alberta, Canada

Comparison of Flocculation Properties of Hemoglobin and Bovine Blood to Properties of Synthetic Flocculants.
G.J. Piazza, R.A. Garcia, USDA/ARS/Eastern Regional Research Center, Wyndmoor, PA, USA

Polymeric flocculants are used extensively for water purification and inhibition of erosion. We found that some proteinaceous materials are biobased replacements for synthetic polymeric flocculants. We showed that chicken blood and fractions have flocculant activity equal to that of polyacrylamide (PAM). Cost analysis showed that a blood-based flocculant is economically competitive to PAM. The kaolin flocculant properties of bovine blood (BB) and hemoglobin (HEM) were examined to ascertain their suitability to replace nonrenewable synthetic flocculants. Flocculation by bovine blood (BB) and HEM increased at acidic pH. In the presence of NaCl, lower concentrations of BB and HEM were needed for the initiation of flocculation, but the extent of maximal flocculation was hardly affected. The flocculation parameters of BB and HEM were measured and compared to those of anionic PAM, cationic PAM, and poly(diallydimethylammonium chloride (polyDADMAC). The windows of application of BB and HEM are similar to that of polyDADMAC, although a lower concentration of polyDADMAC was needed to initiate flocculation. Similar concentrations of blood, HEM, cationic PAM, and anionic PAM were needed for maximal flocculation. Approximately the same reduction of suspended kaolin was given by HEM and BB as by polyDADMAC and cationic PAM.

Application of Red Pepper Seed (Capsicum frutescens) Flour and Protein in Mayonnaise.
Ebru Firatligil-Durmus, Ozgul Evranuz, Istanbul Technical University, Food Engineering Department, Istanbul, Turkey

Recently more attention has been focused on the utilization of food processing byproducts and wastes. Obviuosly, such utilization would result in the production of various new products for food and contribute these products into foods. Red pepper (Capsicum) has an important role in our export of our country. The by-product or waste of drying, freezing and canning process of red pepper was utilized as feed. These seeds can be used in food industry because of their functional properties of ingredients. The objective of this study is to determine the influence of red pepper seed flour (Capsicum frutescens) and protein on the properties of mayonnaise.All mayonnaise samples showed Non-Newtonian, pseuodoplastic behaviour with thixotropy. Power law (Ostwald-de-Waale model) and Herschel-Bulkley models were suitable for modelling reological properties of mayonnaise samples. Flow index values for all samples was less than 1.0. Flow index value was more away from 1 as a result of increasing in red pepper seed flour and protein content of mayonnaise formulations. Yield stress of mayonnaise samples decreased with addition of red pepper seed flour, on the other hand increased with addition of red pepper seed protein.

A Multi-year Survey on Chemical Composition of Rapeseed and Sunflower Meal Produced in France.
S Dauguet¹, M Krouti², JP Loison¹, C Peyronnet³, A Quinsac¹, F Fine¹, ¹CETIOM, Pessac, France, ²CETIOM, Ardon, France, ³ONIDOL, Paris, France

Since 2003, the chemical composition of rapeseed and sunflower meals produced in the French crushing factories was monitored with a quality survey. In the context of bio-diesel production, the rapeseed meal (RSM) and sunflower meal (SM) availability in France was expected to reach 3 million tons in 2011 (increasing by 90 % from 2006). So, this survey participated to their value-enhancing in animal feeding. Each month, one sample of rapeseed and sunflower meals, from each French crushing factory, was analyzed. The measured characteristics were: dry matter content, oil content, protein content, crude fiber content, glucosinolates content and protein solubility in caustic soda. The first three characteristics were relatively stable and close to references used by feeding industry, but glucosinolates content and protein solubility were much more variable. Differences between factories are noticed on glucosinolates content and protein solubility, due to the effect of the process: in 2009, glucosinolates contents range from 4,7 to 18,5 µmol/g DM. Mean yearly results for sunflower meal are different according to the process: without dehulling or with partial dehulling sunflower meal. These findings were interesting for further experiments on interest of different meal characteristics for animal feeding.

Formation of Electrostatic Complexes within Canola Protein Isolate – (kappta-, iota-, and lambda-type) Carrageenan Mixtures.
A.K. Stone, L. Cheung, M.T. Nickerson, University of Saskatchewan, Saskatoon, Saskatchewan, Canada

The formation of soluble and insoluble electrostatic complexes within admixtures of canola protein isolate (CPI) and kappa-, iota-, and lambda-type carrageenan (CG) was investigated as a function of pH and biopolymer mixing ratio during a turbidimetric pH-titration. Changes to surface charge (zeta potential) were also measured as a function of pH for all individual and mixed systems. Complexation typically follows two pH-dependent structure forming events, corresponding to the formation of soluble (pH_c) and insoluble complexes (pH_φ1). For all CPI-CG mixtures, formation of soluble complexes occurred at pHs greater than the isoelectric point (pI) of CPI (~5.78), where both biopolymers carried a net negative charge; with presumed interactions arising between ordered CG chains and positively charged patches on the protein′s surface. Both pH_c and pH_φ1, shifted to higher pHs with increasing biopolymer ratio until reaching a plateau at a 20:1 CPI-CG ratio for iota- and lambda-type CG or 15:1 for CPI-kappa-CG. For all mixtures, the presence of CG significantly inhibited CPI-CPI aggregation. Electrophoretic mobility measurements indicated that the pH corresponding to net neutrality (zeta potential = 0 mV) shifted from pH 5.78 (pI of CPI) to ~pH 5.00 in the presence of CG, regardless of the CG type.

Optimization of Saccharification/fermentation and Scale-up of Cellulosic Biomass Conversion to Ethanol.
D. Maurer, S. Box, J. de Moura, L.A. Johnson, S. Jung, Iowa State University, Ames, IA, USA

Soybean cellulosic biomass is a good substrate for ethanol production due to its renewability and low lignin content (<5%). We identified the best aqueous ammonia soaking (AAS) conditions to enhance saccharification and fermentation of the biomass to produce ethanol when obtaining soybean fiber recovered from environmentally friendly protease-assisted aqueous extraction processing. This strategy works at 1-kg scale and the benefits of using various enzymes (pectinase, cellulase and xylanase, and their cocktails), and various ethanol-producing microorganisms (S. cerevisiae, E.coli KO11, Z. mobilis) were demonstrated. Scaling-up the process from 1 kg to 6 kg of insoluble fiber treated under three conditions will be reported and compared (AAS, enzymes with S. cerevisiae, and enzymes with E.coli KO11). The kinetics of ethanol production and the carbohydrate profile, as well as composition analysis of residual fiber after saccharification/fermentation will be discussed. The present study reveals the conditions for producing bioethanol from soybean fiber without using any chemical in any step of the process and shows that scaling-up of the process can be easily done without safety and environmental pitfalls that usually accompany chemical pretreatment.

Emulsifying Properties of Canola and Flaxseed Protein Isolates Produced by Isoelectric Precipitation and Salt Extraction.
A. Can Karaca, A.K. Stone, N.H. Low, M.T. Nickerson, University of Saskatchewan, Saskatoon, Saskatchewan, Canada

The emulsifying and physicochemical properties of canola (CaPI) and flax (FlPI) protein isolates produced by isoelectric precipitation and salt extraction were investigated relative to whey protein isolate (WPI). Both protein source and method of production were found to have significant effects on the physicochemical and emulsifying properties of both protein isolates. All proteins carried a net negative charge at neutral pH, whereas surface hydrophobicity for CaPI and FlPI was found to be significantly higher than that of WPI. CaPI and FlPI produced by salt extraction showed higher solubility and interfacial activity compared to those produced by isoelectric precipitation. CaPI showed significantly higher emulsion capacity (~515.6 g oil/g protein) than FlPI (~498.9 g oil/g protein) which was comparable to WPI (520.0 g oil/g protein). However, emulsion activity and stability indices for CaPI and FlPI were significantly lower than that of WPI. Creaming stability of emulsions stabilized by CaPI and FlPI ranged between 86.1 to 96.6%, which was comparable to WPI-stabilized emulsions (90.8%). The mean droplet diameter for FlPI-stabilized emulsions (~11.7 μm) was smaller than that of CaPI-stabilized emulsions (~14.8 μm). These results suggest that CaPI and FlPI have emulsion forming properties; however their stability is low when compared to WPI.

Impact of Rheological Properties of Soybean Cellulosic Biomass on Ethanol Production.
A. Meyers, C. Augereau, S. Jung, Iowa State University, IA, USA

Enzyme-assisted aqueous extraction of soybean oil can be performed with the aid of protease (protease assisted aqueous extraction, PAEP), or carbohydrase (carbohydrase-assisted aqueous extraction, CAEP), both processes leading to oil extraction yields similar to the current industrial hexane-assisted extraction. Each process involves specific steps that impact the properties of the three streams; the oil, protein-rich, and fiber-rich fractions. The present study focuses on the fiber fraction with low lignin content (<5%). The impact of each process on the compositional analysis, particle size distribution, swelling capacity, water and oil retention, and rheological properties of the fiber fractions will be presented. Properties of the initial biomass limit its loading and consequently the maximum ethanol concentration that could be obtained. After 24 h and at a 2% glucan loading and 35°C, the CAEP fiber had 2092 cP viscosity vs. 4157 cP for PAEP fiber. Our results clearly identified the benefit of adding pectinase, cellulase or their cocktail on maximum glucan loading. The impact of incubation temperature on viscosity profile during incubation also illustrated the importance of this parameter. These data will contribute to identifying conditions of saccharification/fermentation that will increase ethanol production from this renewable soybean biomass.

Effect of Sunflower Seeds Quality on Dehulling Process in Order to Produce Protein Content Guaranteed Meal.
S. Dauguet¹, C. Guillemain¹, P. Carre², F. Fine¹, ¹CETIOM, Pessac, France, ²CREOL, Pessac, France

Sunflower seed dehulling increased protein content in meal but the high variability of seed quality was a problem for optimizing industrial process. The aims of this study were: to measure variability of protein content and dehulling ability of sunflower seeds at the entrance of a crushing plant and to assess strategies in order to improve dehulling process. Protein content, expressed on defatted dry matter (DDM), was obtained by Dumas method, and dehulling ability was determined on pilot equipment based on centrifugal process. This work showed that the origin of lots of sunflower would affect the quality of sunflower seeds. This provided opportunities for crushing plants to optimize the process of dehulling to produce consistent quality meal, with a guaranteed content of protein, while applying a dehulling rate as low as possible, which was economically more interesting. Indeed, one can consider making a management of seeds at the entrance to the factory according to the agricultural region of origin, identifying areas low or rich in protein, to supply with a mixture of seeds more homogeneous. It could be considered an optimization by search of a better quality of crops, for example by genetic improvement, without penalizing the seeds oil content, but also by a rational management of crushing plants supply.

Functional Attributes of Canola Protein-polysaccharide Electrostatic Complexes.
A.K. Stone, L. Cheung, C. Chang, M.T. Nickerson, University of Saskatchewan, Saskatoon, Saskatchewan, Canada

The functional attributes of formed electrostatic complexes involving canola protein isolates (CPI) and a variety of polysaccharides (gum Arabic (GA), carrageenan (CG) (kappa-, iota-, and lambda-type), gellan gum (GG) (native and deacylated), pectin (high (HM) and low (LM) methoxy) and alginate (AL)) were investigated under pH and biopolymer conditions corresponding to the greatest amount of electrostatic interactions. Specifically, solubility, foaming capacity/stability and emulsion capacity/stability were assessed. CPI-CG (all types), CPI-GG (native and deacylated) and CPI-AL experienced strong electrostatic forces and formed precipitate-type structures, whereas CPI-GA and CPI-pectin (LM and HM) experienced weaker forces and therefore formed coacervates. In general, biopolymer mixtures that precipitated showed reduced solubility and foam/emulsion capacities relative to CPI alone, whereas foam/emulsion stabilities were found to be similar. In contrast, biopolymer mixtures that formed coacervates had similar solubility as CPI alone. CPI-GA and CPI-LM were found to have similar foam/emulsion stabilities but reduced foam capacities relative to CPI alone; however CPI-GA had a similar emulsion capacity to CPI, whereas CPI-LM-pectin was reduced. CPI-HM-pectin mixtures showed similar foam capacities and foam/emulsion stabilities as CPI alone, however had a slight reduced capacity to form an emulsion.

Acetone/water and Ethanol/water Extraction of Gossypol from Cottonseed Meal.
S.M. Pelitire, M.K. Dowd, SRRC, ARS, USDA, New Orleans, LA 70124, USA

Commercial cottonseed meal was extracted with organic solvents in the presence of phosphoric acid to hydrolyze and solubilize bound gossypol. By refluxing meal with mixtures of either acetone/water or ethanol/water, most of the gossypol could be extracted. Extractions were conducted with a solvent-to-meal ratio of 10:1 (v/w), solvent-to-water ratios between 80:20 and 95:5, and extraction times between 0.5 and 5.0 hr. Both solvents resulted in some meals with greater than 90% of the initial gossypol removed. Extractions in ethanol removed the gossypol much faster than extractions in acetone and produced meals containing less than 0.06% total gossypol (corresponding to better than 95% removal). Adding a water wash after the extraction reduced product yields (due to extraction of soluble carbohydrates and albumins) but produced final meals with greater protein concentrations. By undergoing this process, glanded cottonseed meal might be suitable as a non-ruminant protein feed ingredient. The scale of the extractions will be increased to produce sufficient meal to test in aquaculture applications.

Optimization of Inhibition of Alzheimer's β-amyloid (Aβ 1-42) Peptide Aggregation by Soy Protein Hydrolysates using Response Surface Methodology.
Madhuram Ravichandran, Navam Hettiarachchy, University of Arkansas, USA

Soy bean is the richest source of protein (~ 40%) among legumes and is grown as a pulse crop around the world. Soy protein isolate (SPI), has the highest protein content and wide range of health benefits.In this study we aim to evaluate the anti-aggregative property of tryptic/prolyl hydrolysates of SPI. SPI was prepared from defatted soybean meal,with protein and lipid content of 48.2% and 0.8% respectively by alkaline solubilization (pH 9.5).Since the anti-aggregative properties against Alzheimer's β-amyloid peptide (Aβ 1-42) depends on the peptide composition of the hydrolysates and the enzyme used, the effect of process conditions on SPI hydrolyzed with trypsin/prolylhydrolase was investigated systematically using response surface methodology. Hydrolysis conditions for optimal β-amyloid aggregation inhibition were defined using the response surface model of fractional factorial design (FFD), steepest ascent design, and central composite design (CCD). It was shown that the anti amyloid aggregative activity of soy protein hydrolysates could be controlled by regulation of five process conditions pH (7-9), temperature (45-55 ̊C) , enzyme/substrate ratio (0.8-0.1%), substrate/water ratio(10-20%) and time of hydrolysis (1-2hr) by FFD.

Antifungal Activity of Juniper Extracts.
F.J. Eller¹, I. Tumen², C.A. Clausen³, J.A. Teel¹, ¹FFR-NCAUR, USDA-ARS, Peoria, IL, USA, ²FPC, Bartin University, Bartin, Turkey, ³DWP-FPL, USDA-FS, Madison, WI, USA

Sawdust from three species of Juniperus (i.e., J. virginianna, J. occidentalis, and J. ashei) were extracted with hexane or ethanol and the extracts tested for antifungal activity against four species of wood-rot fungi. These species studied represent the junipers with the greatest potential for commercialization. For both solvents, Ashe juniper yielded the highest amounts of extracts followed by eastern red cedar and then western juniper. Gas chromatographic analysis of the extracts revealed significant differences between the species. Western juniper contained the highest levels of cedrol, while Ashe juniper contained the highest levels of thujopsene. The bioactivity of these extracts against several species of wood-rot fungi was also investigated.

Optimum Conditions for Deamidation of Soybean Globulin by Carboxyl Groups on Polymer Matrices.
S. Shimizu¹, Y. Nakanishi¹, M. Ijichi¹, M. Akao¹, H. Kumagai², H. Kumagai¹, ¹Department of Chemistry and Life Science, Nihon University, Kanagawa, Japan, ²Department of Food Science and Nutrition, Kyoritsu Women's University, Hitotsubashi, Chiyoda-ku, Tokyo, Japan

Deamidation is an effective means of improving the functionalities of food proteins. Our previous study showed that carboxylated cation-exchange resins effectively deamidated proteins without causing peptide-bond hydrolysis, and that the deamidation reaction proceeded favorably at low sodium concentrations at the weak alkaline pH. However, deamidation reaction of proteins by the carboxyl groups attached to polymer matrices in various solutions has not been investigated in detail. The present study aimed at examining the effect of salt and solution pH on the deamidation of proteins by polymer-supported carboxyl groups. Soybean globulin was dissolved in various buffered solutions at the same pH or in phosphate buffer solutions with various pH values and then mixed with carboxylated cation-exchange resins for a certain period. After removal of the resins, the deamidation level of soybean globulin was measured. The affinity of soybean globulin in various solutions with the polymer-supported carboxylates was analyzed using a surface plasmon resonance (SPR) biosensor. At neutral pH, the deamidation level of soybean globulin was the highest in a phosphate buffer. When reacted in phosphate buffers at various pH values, maximum deamidation of soybean globulin occurred in the solution at pH 6.0. The binding strength of soybean globulin with the carboxylates in the dextran matrices of the SPR biosensor was well correlated with the deamidation level.

Effects of Oil Extraction on Functional Properties of Protein in Pennycress (Thlaspi arvense) Seed and Press Cake.
M.P. Hojilla-Evangelista, R.L. Evangelista, USDA ARS NCAUR, Peoria, Illinois, USA

Current interest in pennycress (Thlaspi arvense) comes from its seed oil, which is being evaluated for biodiesel production. The seed has notable protein content (33% db). Effects of oil processing conditions on functionality of pennycress seed proteins were determined to identify potential uses for the meal. Whole seeds were either simply cold-pressed or heated to 82°C and then cooked for 20 min in the seed conditioner. Oil was extracted by screw-pressing. Composition and functional properties (solubility, foaming, emulsification, water-holding capacity) of extractable proteins in press cakes and unprocessed pennycress seed were determined and compared. Pennycress seed protein had mainly albumins and globulins, no prolamins, and few glutelins. Cooking significantly reduced the amounts of albumins and globulins in the press cake. All samples showed the lowest solubility (10%) at pH 4 and only moderate solubility (35-45%) as pH increased. Surface hydrophobicity index indicated considerable protein aggregation. Both seed and press cake proteins had excellent foaming and emulsifying properties, but press cake proteins had higher water-holding capacities. These results showed that protein in pennycress seed and press cake is sensitive to heating but still has useful functional properties.

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