2008 Edible Applications Technology
EAT 1 / LOQ 1: Omega-3 Lipids: Application and Stability
Chair(s): C. Hall, North Dakota State University, USA; and M. Tulbek, North Dakota State University, USA
Raw Material Sources for the LC Omega-3 Fatty Acid Market, Trends, and Sustainability. A.P. Bimbo, International Fisheries Technology, Kilmarnock, VA, USA
It seems that a day doesn't go by when some article appears in the popular or scientific press declaring a growing shortage of fish oil in its key global markets. Reports and forecasts of El Nino events, earthquakes in Peru and environmental predictions that ocean fish are being pursued to extinction add to the doom and gloom situation. While most of the concerns have been raised in regard to the aquaculture industry where fish oil and fishmeal are highly desired products, questions have also been raised from groups within the nutritional oils and nutraceutical industry about the reliability of the fish oil supply. While the questions related to aquaculture are routinely addressed, the issue of raw materials for the long chain (LC) Omega 3 nutritional oils or nutraceutical market has only been addressed briefly. This presentation will attempt to put the Omega 3 fish oil situation, especially regarding its relationship to the nutritional oils industry, into perspective.
Addition of Caffeic Acid, Ascorbyl Palmitate, or γ-Tocopherol to Fish Oil Enriched Energy Bars Affects Lipid Oxidation Differently. A.F. Horn, N.S. Nielsen, C. Jacobsen, Department of Seafood Research, National Institute of Aquatic Resources, Technical University of Denmark, Kgs. Lyngby, Denmark
Fish oil enriched food products are highly susceptible to lipid oxidation, which might lead to a loss of the beneficial LC n-3 fatty acids, and potential off-flavour formation. The current study aimed at investigating the effect of antioxidants on lipid oxidation in energy bars enriched with 5% fish oil. The antioxidants studied were the hydrophilic caffeic acid, the amphiphilic ascorbyl palmitate, and the hydrophobic γ-tocopherol. γ-Tocopherol reduced oxidation in concentrations above 440 μg/g fish oil, while caffeic acid or ascorbyl palmitate in all concentrations tested were prooxidative, by increasing the formation of lipid hydroperoxides and volatile oxidation products. Chemical findings were supported by sensory analysis. The differences in the efficacy of the three antioxidants examined are expected to relate to their different localizations and mechanisms of action. To our knowledge studies on lipid oxidation in solid matrices as bread and biscuits are very scarce, and only one study has previously been performed concerning fish oil enriched energy bars. Thus, the current study is dealing with a new area of lipid oxidation research, and data demonstrate that further knowledge in this area is needed in order to elucidate the mechanisms responsible for the present findings.
Enrichment of Dairy Products with Omega-3: Benefits and Challenges. B. Farhang, Y. Kakuda, Food Science Department, University of Guelph, Guelph, Ontario, Canada
Omega 3 fatty acids have been known as essential fatty acids and have numerous health benefits such as prevention of cardiovascular diseases and cancer, as well as improvement of the brain function. Increased demand for functional foods, has led to attempts to enrich milk and dairy products with omega 3. .The primary aim is to develop nutritionally enhanced dairy products that are oxidative stable and have acceptable sensory properties with no development of off flavor during storage or by exposure to light throughout the processing, packaging, distribution chain, and at the retail level but a major challenge in functional food development is to ensure that products are accepted according to the sensory properties. Omega 3 fatty acids are unsaturated and suspectable for oxidation and producing off-flavor, therefore this paper will review the different methods and technigues for stabilizing omega 3 and the recent efforts done for stability improvement in enriched omega 3 dairy products and outlines some suggestions for future work in order to improve the oxidative stability and quality of Omega 3 enriched dairy products.
Evaluation of the Impact of Packaging Methods on the Oxidative Stability of Milled Flaxseed. Mehmet Tulbek1, Clifford Hall III2, Bin Zhao3, 1Northern Crops Institute, Fargo, ND, USA, 2North Dakota State University Department of Cereal Science, Fargo, ND, USA, 3Kraft Foods Global Inc., East Hanover, NJ, USA
Flaxseed (Linum usitatissium) is an emerging phytochemical source for the functional food industry. Flaxseed contains secoisolarecinol diglycoside and high content of alpha-linolenic acid (ALA, omega-3) which were reported to be beneficial for the prevention of heart disease and varioius cancers. Flaxseed is susceptible to oxidation and alpha-linolenic acid can further oxidize into aldehydes and alcohols during storage. The objective of this study is to investigate the storage stability of ground flaxseed under various packaging methods. The oil stability of milled flaxseed stored at 30°C and 60°C was evaluated. Milled flaxseed stored in plastic bags had significantly higher (P<0.05) aldehyde content than milled flaxseed stored in aluminum bags. Pentenal and hexenal aldehydes were found to be higher in the 7-week stored plastic bag samples compared to 3-week samples. Results indicated that the aluminum-foil packaging can provide better shelf life stability than the plastic packaging application. Significant differences were observed among the vacuum packaging compared to combined nitrogen flush vacuum packaging application.
Effects of Flaxseed Particle Size on Dough and Bread Characteristics. C. Hall III1, M. Tulbek2, S. Meyers1, 1North Dakota State University, Fargo, ND 58105, USA, 2Northern Crops Institute, Fargo, ND 58105, USA
Flaxseed in bread making has been investigated extensively; however, limited research on dough and bread characteristics in relation to particle size has been reported. In previous work using milled flaxseed in baking, particle size of the milled or ground flaxseed has been neglected and only the percentage of the flaxseed in the dough was deemed the most important contributor affecting dough and bread characteristics. The objective of this research was to determine the effect of flaxseed particle size on dough rheology and bread characteristics. Traditional dough rheological tests were conducted on bread dough containing 15% of ground flaxseed having a particle that size of >850, 600-850, or <600 µm. Standard bread formulas were made with the 15% ground flaxseed have the different particle sizes. Bread characteristics and oxidative indicators also were measured. In general, flaxseed particle size did influence the rheological properties of the dough. Flaxseed particles caused varying effect s on dough behavior. In general, the intermediate particles (600-850) affected the rheological properties the least. The very small flaxseed particles likely caused a disruption in the gluten matrix thus affecting dough properties. Oxidation of the breads followed similar patterns as the rheological behavior. Thus, particle size should be considered in products containing flaxseed.
Roasting of Seed Prior to Oil Extraction Improves the Oxidative Stability of Canola Oil. Chakra Wijesundera, Peter Fagan, Claudio Ceccato, Zhiping Shen, CSIRO Food Science Australia, Werribee, VIC, Australia
Canola (Brassica napus) is Australia's primary oilseed crop. Canola quality Indian mustard (Brassica juncea) is also being developed for cultivation in hot and low rainfall areas of the country where canola does not perform well. There is an increasing trend within the food service industry in Australia to use canola oil as a substitute for animal fats and partially hydrogenated oils (trans fats) used for deep-frying. However, such efforts are hampered by the susceptibility of canola oil to oxidative deterioration. Laboratory-scale accelerated oxidation tests have shown that the oxidative stability of unrefined oils from both B. napus and B. juncea can be improved significantly by roasting the seed prior to oil extraction. Roasting did not alter the fatty acid composition or the tocopherol content of the oils. The enhanced oxidative stability imparted by seed-roasting is probably due to the production of 2,6-dimethoxy,4-vinylphenol (DMVP) by thermal decarboxylation of sinapic acid which naturally occurs in canola seed. Although response surface methodology showed that the highest concentration of DMVP was obtained by roasting seed at 165° C for 13 min, a roasting time of 5 min is recommended to prevent deleterious effects on the flavour of the oil.
Processing and Characterization of Soy Oil Containing Stearidonic Acid as an Omega-3 Source. J. Heise, Monsanto Company, St. Louis, MO, USA
Soybeans containing stearidonic acid (SDA) at levels of 20 to 30% in the oil have been developed utilizing biotechnology. Benefits of SDA, an 18:4 Omega-3 fatty acid, include increased bio-conversion to EPA relative to ALA and improved flavor and shelf-life characteristics as compared with fish and algal oils. Although SDA is more easily prone to oxidation than ALA, conventional soybean processing produces high quality oil which is suitable for a variety of food applications. The processing of SDA soybeans and characteristics of the oil produced, including comparative stability data and sensory attributes, will be presented.
Development of Foods Incorporating Stearidonic Acid as an Omega-3 Source. R. Wilkes, Monsanto Company, St. Louis, MO, USA
Current sources of Omega-3s have limitations from poor bioconversion of ALA to the more desirable forms of EPA and DHA, and flavor and shelf impact of using fish and algal oils. Utilizing biotechnology, soybeans have been successfully produced that are enhanced with stearidonic acid (18:4ω3) (SDA). The benefit of SDA is improved flavor and shelf life compared to fish and algal oils and significantly increased bioconversion to EPA compared to ALA. In a pilot clinical study subjects that incorporated SDA in their diets for 16 weeks significantly increased the Omega-3 Index over subjects in the ALA containing soy oil control group and were similar to subjects consuming EPA. Studies were conducted to determine the flavor and consumer acceptance impact of SDA when incorporated in food. Soybean oil containing 20% SDA was added to several foods including salad dressings, margarine, yogurt, yogurt drinks and granola bars. Each product was evaluated using descriptive sensory analysis to determine flavor differences vs. a control throughout the product's typical shelf life. Results indicate that only minor flavor differences were observed and desired shelf targets were obtained. In addition, consumer acceptance results show that food products containing SDA are equally liked for overall liking and flavor liking as the control foods.
Fat and Oil Mixtures with an Nutritionally Interesting Fatty Acid Profile. Nathalie De Clercq , Koen Dewettinck, Ghent University, Ghent, Belgium
Today, cardiovascular diseases (CVD) are death cause number one in the Western society. Another prosperity disease, type 2 diabetes is reaching epidemic proportions. This is also enforced by the fact that more and more people are becoming obese. The major cause of these diseases is the too fat rich diet and moreover it contains too much “unhealthy” fat, like trans and saturated fatty acids. One of the strategies to make the fat healthier is changing the fatty acid profile. This requires a multifaceted approach, which includes a well-informed and motivated consumer and the availability of affordable, acceptable food products with enhanced fatty acid profile. In this study palm oil, its low melting fraction palmolein and its high melting fraction palmstearin where blended with three oils with a healthy fatty acid profile. For this purpose hazelnut oil (88% C18:1; 10% C18:2); rice bran oil (42% C18:1; 33% C18:2) and walnut oil (20% C18:1; 49% C18:2; 12% C18:3) were selected. Blending was preferred because it has the advantage that no chemical processes are involved . The changing of the fatty acid profile may have major implications on the physicochemical properties. In this research the underlying mechanism of these properties is revealed so that changes can be made in an adequate way. Techniques like NMR, DSC and HPLC-ELSD are used in this research.
Development of Novel Crop Sources of Stearidonic Acid for Human Consumption. K. Coupland1,2, A. Hebard2, M. Surette3, 1University of Hull, Hull, Yorkshire, UK, 2Technology Crops International, Winston-Salem, NC, USA, 3University of Moncton, Moncton, New Brunswick, Canada
Polyunsaturated fatty acids are well established as important components of a healthy diet. In particular lipids containing long chain n-3 fatty acids such as eicosapentaenoic acid (EPA) are known to have positive health benefits. Plant derived n-3 fatty acids such as α-linolenic acid have been promoted as precursors to EPA. The efficiency of this conversion is however extremely low. There is a clear need for a sustainable source of EPA from a renewable source since currently the main sources of EPA-containing lipids are marine oils. This is a declining resource due to over-fishing and the cost and availability of high quality fish oil is becoming problematic. It is now known that stearidonic acid (SDA), found in some plant lipids is rapidly and efficiently converted to EPA in the body. It is proposed that SDA-containing plant oils could be a viable alternative to fish oil. Certain plants of the Boraginaceae family have been shown to contain significant amounts of SDA and this has led to the commercialization of one species, Echium plantagineum. Recent research and development has discovered other promising plant sources with both a high SDA content and a more attractive lipid profile. In vitro experiments have confirmed the value of these plant lipids in raising levels of EPA and reducing inflammatory markers.
EAT 2: Trait Modified Food Oils: Characteristics and Their Use
Chair(s): F. Orthoefer, FTO Consulting, USA; and G.R. List, USDA, ARS, retired, USA
Low Lin Soybean Oil and Beyond. R. Wilkes, Monsanto Company, St. Louis, MO, USA
Low Linolenic soybean oil is the first in a series of modified oilseeds introduced to meet food company and consumer needs. This presentation will review the current use of low linolenic soybean oil allowing CPG and foodservice companies to successfully replace partially hydrogenated soybean oil. Many food processors have chosen low linolenic soybean oil based on taste, performance and cost benefits. This has resulted in the reduction and elimination of trans fats from the food supply, meeting consumer demand for healthier foods. Seed companies continue to utilize traditional breeding, marker assisted breeding and biotechnology to modify oilseeds that yield oils with health and nutrition benefits. Additional modified oilseeds are at various stages of development. Soybeans with increased levels of stearic acid are being developed to provide an alternative to partially hydrogenated fats and high saturated fats required to provide solids and structure to food. High stability fry oils with increased levels of oleic acid, reduced levels of linolenic acid as well as a version with lower saturated fat are being pursued. Soybeans are also being modified to provide more sustainable sources of Omega-3s including stearidonic acid (SDA) and EPA/DHA which will provide more bioavailable levels of Omega-3s compared to ALA and improved functionality/stability compared to fish and algal oils.
Increasing the Oleic Acid in Soybean Oil with Plant Breeding. J. Burton1, J. Gilsinger2, 1United States Department of Agriculture Agricultural Research Service, USA, 2Monsanto, USA
Increasing the oleic acid content along with a decrease in linolenic acid can improve the oxidative stability of soybean oil. Genetic changes in soybean using standard plant breeding practices has resulted in a publicly released a mid-oleic breeding line, N98-4445A, with oil that averages 57% oleic acid and 2.5% linolenic acid. Reciprocal effects for heritability and stability were examined in twelve F2 derived populations over two years developed from reciprocal crosses between N98-4445A and varieties, Arksoy, Dare, Haberlandt, Midwest, Ogden, and Peking. Significant differences in heritability and stability between reciprocal populations were observed, suggesting it may be advantageous to make reciprocal crosses when developing populations for altered fatty acid selection in soybeans. Molecular markers were used to make the selection of the high oleic types more efficient in two breeding populations. Significant marker-trait associations for oleic acid content, seed quality, and yield were observed in both populations. These results demonstrated that these markers could be useful for marker-assisted selection of the mid-oleic trait across populations and could be used to improve seed quality and yield. Results will also be presented which show the effect that environment can have on the stability of the mid-oleic trat.
Mid Oleic and High Oleic Sunflower Oil. L. Kleingartner, National Sunflower Association, USA
Sunflower has been modified through conventional breeding practices to provide vegetable oil that is naturally stable. Linoleic acid (18:2) levels were and oleic acid (18:1) levels were increased to levels of 60 to 90 percent. This genetic work was done in the late 1990s in anticipation of trans becoming a food label requirement. Mid-oleic sunflower oil, NuSun® is now commercially available and is widely used in the production of potato chips. High oleic sunflower oil (HOSO) is generally 84 percent or higher oleic acid and has been commercially available for a longer time. The presentation will further examine this development the characteristics of these oils as well as statistics on production, utilization and the future outlook of sunflower production in the U.S. and other countries.
High Oleic, Low Linolenic Canola Oil. M. La Guardia, Dow AgroSciences, LLC, USA
Plant breeding technology for specific performance and nutrition traits will be compared with hydrogenation technology. Functional, stable, high oleic, low linolenic canola oil will be characterized and compared with other widely used vegetable oils. This fatty acid composition will be examined to demonstrate the oils' application as a multi-functional ingredient or a frying medium. The nutritional profile, sensory qualities, and critical performance characteristics, such as flavor, color, shelf life and fry life will be reviewed.
Progress in the Characterization of High Stearic High Oleic Sunflower Oil and Its Fractions for Different Food Applications. E. Dubinsky1, R. Garces2, A. Leon3, 1Eduardo Dubinsky & Associates, Technical Consultants, Buenos Aires, Argentina, 2CSIC, Spain, 3Advanta Semillas, Balcarce, Buenos Aires, Argentina
Stearic acid is the unique fatty acid that can yield healthy solid fats. By means of fractionation by crystallization of High stearic High oleic sunflower oil different products with different melting profiles could be obtained, tailored for almost every food application. The main target of the product development is focused in obtaining a stearin fraction for cocoa butter alternatives (cbe and cbr), and a very stable olein fraction specially for industrial frying. This means the possibility of having healthy products for replacing of trans fats and "bad" saturates different from stearic that increase the cholesterol and the risk of CVD.
EAT 3: Formulating Foods with Healthier Oils
Chair(s): E. Hernandez, Omega Pure, USA and F. Orthoefer, FTO Consulting, USA
Definitions, Regulations, Recommendations for Healthier Oils. P. Kearney, PMK Associates, Inc., USA
Emerging research on the consumption of trans fatty acids (TFAs) has shown negative effects on health and disease risk. Clinical data has shown that even in small quantities, TFAs more potently affect blood lipids than saturated fats because they raise "bad" LDL cholesterol, but also lower "good" HDL cholesterol. The latest science shows that TFAs can promote inflammation at the cellular level and that inflammation is the root common denominator of many chronic diseases. At the same time, human nutrition science continues to show a favorable effect of mono- and polyunsaturated fatty acids on lipids and chronic disease risk.Major scientific groups, including the U.S. Dietary Guidelines Committee and the American Heart Association agree that TFAs should be limited to less than 1% of energy, while "good" mono- and polyunsaturated fats, that are found in healthy oils, should be the major fats in our diets.On January 1, 2006, the Food and Drug Administration required that nutrition labels list the content of TFAs, when above 500mg per serving. Thus, food manufacturers have been challenged to eliminate TFAs and to reformulate foods with healthier oils. Campaigns to enact legislation to ban trans fats have also been considered in U.S. state and local governments and the trend continues.With the removal of partially hydrogenated oils and TFAs from foods, research continues to support the use of healthier oils, low in both trans and saturated fats, as alternatives.
Performance of Healthier Oils in Snack Foods. W. Mongana, C. Norman, C. King, Texas Womens University, Denton, Texas, USA
The use of hydrogenated oils have been used to produce a stable frying oil with a long fry life. In order to avoid the use of hydrogenated oils, oils such as cottonseed oil (CSO) and high oleic low linolenic (HOLL) canola oil, are used as alternatives. In this frying study, potato chips produced by Lamb Weston were fried in CSO and HOLL for a total of 13.5 hours over 4 days. Oil samples were collected at the beginning of the frying process as well as after 5, 10 and 13.5 hours of frying for chemical analysis of oil decomposition during frying. Free fatty acid values for 0, 5, 10, and 15 hours were: CSO 0.16, 0.2, 0.43, and 0.38% and HOLL were 0.28, 0.32, 0.41, and 0.18%, respectively. Para-anisidine values were also calculated. Over 0, 5, 10, and 15 hours, CSO values were 3.78, 28.14, 32.9, and 36.57 and HOLL values were 1.78, 15.39, 24.77, and 27.15, respectively. The fatty acid profile of CSO and HOLL before and after frying will be determined by gas chromotography. Results indicate that HOLL can be used for frying potato chips in order to produce a high quality fried product.
Is High-Oleic Low-Linolenic Canola Oil Suitable to Improve the Storage Stability of Foods Being Fried?. B. Matthäus1, N. Haase2, G. Unbehend2, 1Institute for Lipid Research, Münster, Germany, 2Institute for Cereal, Potato and Starch Technology, Detmold, Germany
Research has shown that high-oleic, low-linolenic (HOLL) canola oil is suitable as a frying medium, because it is a good compromise between technological and nutritional demands. The oil results in high-quality, tasty food, has a high oxidative and thermal stability during processing and has some advantages with regard to health aspects, because it contains no trans-fatty acids and only low amounts of saturated fatty acids.The problem of conventional canola oil is that the use results in high-quality products after frying, but during storage the products become inedible very fast. The presentation shows the behaviour of Berlin doughnuts and potato crisps being fried in HOLL canola oil in comparison to products being fried in high-oleic sunflower oil, palm olein and different types of partially hydrogenated oils.During storage the quality of products being fried in HOLL canola oil was comparable to products being fried in other common used oils with regard to the chemical parameters. The sensory evaluation of potato crisps being fried in HOLL canola oil was comparable to other oils. The sensory evaluation of Berlin doughnuts being fried in HOLL canola oil was comparable to doughnuts being fried in partially hydrogenated oils but worse to doughnuts being fried in palm olein.
Enzymatically Interesterified Soybean Oil-Based Margarine and Shortening; Functional Low trans Alternatives for the Food Industry. T. Tiffany, N. Widlak, D. Dunford, Archer Daniels Midland Company, Decatur, IL, USA
Low trans bakery shortening and bakery margarine products have been formulated to meet the requirements needed to list zero grams of trans per serving on retail food products. Through enzymatic interesterification commercial quantities of functional basestocks for the production of shortenings and margarines are produced by combining together soybean oil with fully hydrogenated soybean oil. Rearrangement of the fatty acids from soybean oil and fully hydrogenated soybean oil by enzymatic interesterification produce basestocks with melting properties similar to that of partially hydrogenated soybean oil. Overall, the complete balance of fatty acids present in enzymatically interesterified soybean oil based low trans alternatives is much different compared to the higher trans partially hydrogenated soybean oil based shortenings and margarines that are being replaced. This paper will review the characterization low trans enzymatically interesterified bakery shortening and margarine along with functional evaluation in a variety of baked goods.
Trait Modified Oils in Spray Applications. M. Gupta, MG Edible Oil Consulting Int'l., USA
Spray oil is used on crackers for imparting the following important traits in the product:- Shiny surface appearance - Improved moistness - Pleasant mouth feel - Appealing flavor Traditionally, partially hydrogenated soybean oil or cottonseed oil has been used in this application. This incorporated a significant amount of trans fatty acid in the product. Modified composition oils, especially those with low linolenic acid content can be used in several food applications without any hydrogenation. These include oils like low linolenic soy, canola, mid-oleic sunflower, soy, canola, high oleic sunflower, canola and ultra low linolenic soybean oil. One could expect good flavor performance from most of these modified composition oils. While these oils produce satisfactory pilot plant results, there can be some issues with increased polymerization of the oil on the processing equipment due to the high linoleic acid content and lack of crystallization. This could be expected for low linolenic soy, ultra low linolenic soy, mid-oleic sunflower oil. Some special care must be taken to avoid any polymerization if it happens. In this discussion, the author will discuss the pilot plant performance of the modified composition oils as spray oils for crackers.
Performance of Trait Modified Oils in Frying Applications. M. La Guardia, Dow AgroSciences, LLC, USA
A review of various trait modified oils and their relative performance in frying and on food quality will be presented. The presentation will focus on critical quality control parameters, sensory characteristics of the oil, and most importantly, the flavor of the food.Frying oils have renewed attention due to the rising cost of vegetable oils, and the need for improving the nutritional profile.Realizing the performance advantages and capturing the value of trait enhanced oils will be discussed.
Formulating Foods with Omega-3 Fats. Opportunities and Challenges. E. Hernandez, Omega Pure, USA
The general consumer is increasingly aware of the health promoting properties of n-3 fatty acids. As a result there has been an increase in the consumption of omega 3 fatty acids either as dietary supplements or in in fortified foods. Polyunsaturated oils such as omega 3 oils are inherently unstable and this presents several challenges when incorporating them to foods. This is due to the rapid deterioration during processing, handling or storage. Residual fishy taste and aroma is one of the major obstacles for the food industry to increase acceptance of omega 3 fortified foods. There are already a number of fortified foods and supplements already in the market aimed at the general population, especially babies, lactating mothers and baby boomers. One approach to increase the omega-3 fats content in the diet is to introduce their consumption through conventional foods without having to ask the consumer for a radical change in eating habits. Examples of food products and nutritional supplements rich in omega 3 oils already in the market include dairy products, beverages, margarines and spreads, salad dressings. This paper will present specific applications of long chain omega 3 fats into foods including challenges involved to prevent off flavor development during processing and storage of fortified food and supplements.
EAT 4.1: Crystallization
Chair(s): S. Narine, University of Alberta, Canada; and N. Widlak, Archer Daniels Midland Co, USA
Use of Laser Backscattering To Monitor Nucleation and Growth during the Isothermal and Non-Isothermal Crystallization of Palm Oil in A Stirred Vessel. E. Hishamuddin1, A.G.F. Stapley2, Z.K. Nagy2, 1Malaysian Palm Oil Board (MPOB), Bandar Baru Bangi, Selangor, Malaysia, 2Loughborough University, Loughborough, Leicestershire, United Kingdom
Monitoring the characteristics of particles, particularly in the crystallization of fats is important in understanding crystallization behaviour and to facilitate the design of downstream processes. The focused beam reflectance measurement (FBRM) method is a popular way of detecting the onset of nucleation and analysing in-situ changes in particle dimension, concentration and population. In this study, palm oil was crystallized from the melt under isothermal (24, 26, 28 and 30°C) and constant cooling (0.1, 0.3 and 0.5°C/min) conditions. It was observed that FBRM was capable of detecting the onset of nucleation as well as providing continuous indications of nucleation rate and crystal chord size distribution. Data from non-isothermal experiments showed convincing evidence of two separate crystallization processes occurring in the same vessel, whereas isothermal experiments indicated a single smooth response curve for both the nucleation rate and mean chord size. As expected, smaller crystal sizes were found at the lower isothermal hold temperatures. There was also some evidence that secondary nucleation caused by crystal breakage occurs. The results from the FBRM are also being used to complement compositional analysis of the fractions collected during filtration.
The Physical and Functional Properties of Vegetable Oil Organogels. N.E. Hughes1, A.G. Marangoni1, J.W.E Rush2, M.A. Rogers1, K. Dupak2, 1University of Guelph, Guelph, ON, Canada, 2University of Waterloo, Waterloo, ON, Canada
The ability of 12-Hydroxystearic Acid (12-HSA) to form structured vegetable oil organogels may have exciting new applications in the food industry. The exploitation of the oil binding capacity of 12-HSA to decrease the rate of oil migration in multi-component foods was studied using a scanner imaging technique. 12-HSA (0-2% w/w) was incorporated into the coating and/or filling of a model system of cream-filled chocolate and the front of oil migration of the stained cream phase was observed over time. Contrary to our original hypothesis, the incorporation of 12-HSA (2% w/w) into the cream phase actually increased the rate of oil migration through non-tempered cocoa butter from 0.13620±0.005798 to 0.21960±0.028570 mm/day. The incorporation of 12-HSA into the model coating (non-tempered cocoa butter) had no significant effect on oil migration.Vegetable oil organogels may also be used as a healthier alternative to conventional spreads. The consumption of canola oil gelled with 2% w/w 12-HSA is associated with an attenuated increase in serum triglyceride levels compared to butter or margarine. The preparation, stabilization, and potential food applications of 12-HSA organogel emulsions (20:80, w/o) will also be discussed.
A Rheo-NMR System for the Determination of SFC Under Controlled Shear Flow. E.M. Mudge, E.Y. Anom, G. Mazzanti, Dalhousie University, Halifax, NS, Canada
The mechanical, sensorial, thermal and diffusional properties of multicomponentedible lipid systems depend dramatically on their solid fat content (SFC) and theirnanostructures, which are affected by the shear rate applied. A mini-Couette cell wasdeveloped to shear fat samples, and was tested with blends of canola stearin in canola oil in a 20MHz pulsed NMR spectrometer. The blends were placed in the mini-Couette cell,melted at 80 °C, and then crystallized under different shear rates (50 s-1 to 400 s-1) at 40 °Cinside the spectrometer. Time averaged NMR free induction decay curves were captured at20 s intervals, and the SFC values calculated using parameters determined by a calibrationprocedure.The SFC values determined by the direct method with and without the shaft of the Couettedevice, and with and without shear in the Couette device were reasonably close. The FID curvesdid not show a significant difference either. Therefore we conclude that this system is accuratefor in-situ time-resolved determination of SFC under shear flow. A combination of the direct andindirect method was successfully used to determine viscous heating.The system developed will help in understanding the effects of shear flow on the volumefractions of nanostructured lipid multicomponent systems. This will permit to optimizemanufacturing processes.
Rheo-NMR Measurements of Cocoa Butter Crystallized Under Shear Flow. E.M. Mudge, G. Mazzanti, Dalhousie University, Halifax, NS, Canada
The dramatic polymorphic changes that shear flow induces on crystallizing cocoa butter have enormous impact on the confectionery and cosmetic processing industry. A benchtop NMR was modified to monitor the solid fat content (SFC) during crystallization of cocoa butter under shear flow in a mini-Couette cell developed by us. The sample melt at 50 °C was cooled down at 3 °C /min to 17.5, 20.0 or 22.5 °C under shear rates from 45 to 720 s-1. Free induction decay curves were captured every 2 seconds and averaged in groups of 10 to produce a data point every 20 seconds. The SFC was calculated using parameters computed from standard reference materials. This is the first time the SFC of cocoa butter has been measured in situ and in real time during crystallization under shear flow. Another mini-Couette cell was made of the same dimensions as the one used inside the NMR, but made of x-ray transparent materials. This Couette cell was used in the synchrotron to compare the SFC to the polymorphic forms obtained under similar processing conditions. This allowed us to determine proportionality factors that were so far unknown between x-ray integrated intensity and SFC. This method opens the possibility for kinetic studies and for processors to develop realistic studies on the effects of shear flow and temperature profiles on finished products.
Continuing Efforts to Quantify Fat Microstructure and Model its Relationship to Mechanical Properties. A.G. Marangoni , University of Guelph, Guelph, Ontario, Canada
Fat functionality is strongly related to the microstructure of the underlying fat crystal network in the mesoscale length scale. In order to understand, predict and engineer fat functionality it is necessary to quantify this level of structure as completely as possible. Structural features that need to be quantified include the size and size distribution of polycrystals, the interaction forces between crystals, the solid fat content (SFC), as well as the scaling exponent related to the increase in hardness as a function of SFC. Once these structural features have been characterized, it is equally important to have a mechanical model which relates structure to mechanical response. In this talk, I will review existing and new methodology that can be used for the practical characterization of fat mesoscale, including crystal size, fractal dimension of the network and the Hamaker constant of van der Waals' interactions between crystal. I will also review the current state of development of the fractal model of fat microstructure, as well as the linear chain model. The ultimate aim of this work is to be able to calculate a priori the elastic modulus or yield stress of a fat strictly from structural information.
Synchrotron X-Ray Microbeam Analyses of Physical Functionality of Fat Crystals. S. Ueno, K. Sato, , Graduate School of Biosphere Science, Hiroshima University, Japan
Various physical functions of fat crystals are revealed in solid, emulsion, gel and aerated states, in which their microstructures play determinative roles. Traditional methods using DSC, SFC, X-ray diffraction, etc. can provide averaged macroscopic properties of the fat materials, but microscopic information is lacking. By contrast, optical, electron microscopic and AFM methods can provide microscopic features, yet structural details are lacking. The use of synchrotron radiation microbeam technique can provide microstructural properties of fat crystals present in bulk solid, emulsion, air cells and gels, when appropriate simultaneous monitoring of target portions and X-ray detecting systems are facilitated with X-ray microbeam dimension of the order of several micron-meters or less.In this talk, synchrotron X-ray microbeam analyses of fat crystals in spherulite, granular fat aggregates in margarine, O/W emulsion droplets, air cells in whipped oil will be presented. We used X-ray microbeam with the dimensions of 5x5 micron-meters in BL-4A station at Photon Factory, KEK, Tsukuba, Japan. The microbeam X-ray was irradiated at every 20 micron-meter distance on the materials. New findings have been obtained with this method, such as molecular orientation of fat crystals and template-induced polymorphic transformation in fat spherulites, and molecular orientation of fat crystals assisted by interfacial heterogeneous nucleation at the O/W emulsion membrane.
Evidence for Kinetically-Altered Growth Modes of Lipid Networks. S.S. Narine, Alberta Lipid Utilization Program, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
Lipids crystallise in metable states, and the crystallization energetics can result in significant changes to the growth mode of the resulting lipid network. There are a number of mechanisms available to a crystallizing melt for growth of the network, and these growth mechanisms can be selected by altering the kinetics of growth. Furthermore, the growth modes that are defined can result in significantly different physical functionality of the finished network, which may be manipulated by the lipid processor to deliver unique performance characteristics of lipid-containing products. Theoretical underpinnings for the existence of different growth mechanisms will be presented, as well as kinetic and thermodynamic studies on a number of pure and complex lipid ensembles which provide convincing evidence for the existence of crystical kinetics which select for specific growth modes.
Shifting Apparent Eutectics by Selection of Kinetic Growth Modes. L. Bouzidi, S. Narine, University of Alberta, Edmonton, Alberta, Canada
The final functionality of crystal TAG networks developed from the melt is dependent upon several parameters including the crystallization and processing conditions. The growth mechanisms available to a crystallizing melt are shown to be strongly dependent not only on the type of TAG molecules in the system but also on the kinetics of growth. A systematic study of model fat systems made of binary mixtures of TAG isomers will be presented. The influence of the processing conditions on the polymorphism, phase behavior and rheological properties as well as the shifts in the eutectics and SFC depressions and subsequent softening that occurred will be detailed. Phase diagrams constructed using DSC data of the binary systems and the thermodynamic model used to simulate the phase boundaries and investigate the intersolubility of the components will also be discussed.
New Generations Shortenings: Zero trans, Lowered Saturates. K. Humphrey, S. Narine, University of Alberta, Edmonton, Alberta, Canada
The removal of trans fats without increasing the saturated fats is not trivial as both fats tend to have high melting points and contribute to the formation of a solid crystal network. Therefore a series of phase behavior studies of canola and other vegetable oil based shortenings were developed to design a zero trans, lowered saturates shortening with hardness commensurate that of a commercial product which utilizes the structure enhancing properties of specific TAGs.Previous studies have suggested that the final physical properties of the shortenings are significantly influenced by amounts of PSS, PSP, or PPS, in combination with SSS. Given this observation, a canola shortening system was enriched with pure PSS as well as PSS as a component of fully hydrogenated canola and cottonseed oil and the effect of PSS was observed. It was found that by careful blending of hard canola and cottonseed oils one could increase hardness whilst limiting total added saturated fat. The increase in hardness as seen on the lab scale was also observed for shortenings produced at the pilot plant scale. In an effort to further enhance the crystal network formed, the processing conditions and tempering were varied. Finally, the PSS enriched shortenings demonstrated greater suitability for icings than those shortenings without enrichment.
EAT 4: Emulsions
Chair(s): P. Rousset, Nestec SA, Switzerland; A. Wright, University of Guelph, Canada; and F. Maleky, University of Guelph, Canada
Sucrose Fatty Acid Esters: Recent Developments in Food Application. N. Otomo, Mitsubishi-Kagaku Food Corporation, Tokyo, Japan
Food systems are very complex. They consist of many components that are incompatible. Thus there is wide area of interface. Food emulsifiers can affect these interfaces in many ways. Consequently emulsifiers have a variety of functions beside the emulsification of oil and water. To understand the nature of this functionality, it is very important to know the chemical structure and physical properties of emulsifiers. Sucrose fatty acid esters (SE) are unique emulsifiers mainly used in food applications. By changing the number of esterification and the kind of fatty acids, SE can cover very wide range of applications. Due to the strong hydration of OH groups on sugar moiety, they have strong hydrophilic and also lipophobic character. SE are a mixture of esters with different degrees of esterification. We have investigated the molecular shape of each ester which explains the self-organization structure of SE.New SE, sucrose tricaprylate(C8), shows remarkable bacteriostatic activity toward spores of thermophilic bacteria even in the presence of starch which normally inactivates the function by making a complex with fatty acid moiety. Hydrophobic SE are useful for crystal control of fat in chocolate, dairy cream and so on. Some examples will be discussed.
Fatty Acid Microcapsules Made of Non-Digestible Materials. N. Watanabe1, A. Koide1, A. Kuriyama1, K. Fujimoto2, 1Showa Women's University, Tokyo, Japan, 2Koriyama Women's University, Fukushima, Japan
The number of patients with colitis and colon cancer has recently increased in Japan with the westernization of dietary habits. On the other hand, it has been reported that short chain fatty acids are effective in preventing some kinds of colon cancer and trans fatty acids promoted the growth of Lactobacillus in vitro; therefore, the functional fatty acids might help in preventing colitis and colon cancer. However, these functional fatty acids do not reach the large intestine because a large proportion of dietary fatty acids is digested and absorbed from the small intestine. The purpose of the present study was to prepare fatty acid microcapsules using non-digestible materials. First, a fatty acid (oleic acid) was coated with resistant starch prepared from corn starch. The diameter of these microcapsules was 50-200 μm; in vitro, these microcapsules were resistant to pepsin, HCl, and lipase, but not to amylase and emulsifier. Next, glucose and citric acid were used as the cross-linkers. These microcapsules had high resistance to also amylase and emulsifier as well. In vivo experiments will be necessary in the future studies.
Effect of Composition and Processing Parameters on Canola Stearin-Poloxamer 188 Solid Lipid Particles; Size, Polymorphism, and Microstructure. C. Trujillo, A. Wright, University of Guelph, Guelph, ON, Canada
Solid lipid particles (SLPs) are being touted for their potential as encapsulating agents, particularly those which are of submicron size. The purpose of this study was to determine the effect of lipid (5, 10, 20, and 30%) and surfactant (0.0, 0.5, 1.0, 2.5, 5.0 and 10.0 wt%) concentration as well as processing parameters (i.e. homogenization pressures between 500-2500 psi and 1, 3, 5, and 10 cycles) on the 24 hour particle size distribution, polymorphism, and microstructure of SLPs prepared by microfluidization and based on fully hydrogenated canola stearin (CS) and the nonionic emulsifier Poloxamer188 (P188). Mean particle size (i.e. D4,3) ranged from 0.1 to 33.5 μm. P188 and processing pressure had a significant influence on particle size (P<0.05), although the number of homogenization cycles did not (P>0.05). Gelation was sometimes observed for the samples at high lipid contents. Differential scanning calorimetry revealed peak broadening and a decrease in melting enthalpy with increased P188 concentration. By x-ray diffractometry, the presence of proportionally more beta polymorph with increasing P188 concentration was confirmed. Cryo-scanning electron microscopy revealed the presence of clustered, spheroid particles.
Physical Properties of Organogels Using Plant Waxes and Vegetable Oils. L. Dassanayake1, S. Ueno1, K. Sato1, D. Kodali2, 1Hiroshima University, Higashi-Hiroshima, Japan, 2University of Minnesota, MN, USA
Vegetable oil-based organogels were formed using bleached and unbleached rice (Oryza sativa L.) bran wax (RBX). The gelation behaviour, gel structure and stability were studied. Gelation occurred depending on the temperature and vegetable oil composition. Phase diagrams were constructed using salad oil (canola oil: soybean oil) for the two types of RBX. Wax type and concentration has a significant influence on gelation behaviour and gel kinetics. In room temperature, 1% salad oil gels behave like weak, more liquid like gels. Higher concentrations of RBX formed rigid gels. The gels formed with unbleached RBX (yellow) were closer to sol state. However, RBX formed gels with high melting temperature and show quick solidification. Polarized microscopy revealed that the RBX gels were formed through the long, thin, fiber like crystal network. Structural analysis using X-ray diffractometry (XRD) revealed the well defined sub cell structure of RBX compared to the long axis packing. Penetrometer studies showed that the hardness of the gels increased with the wax concentration and the type of vegetable oil used. Viscosity of the gels was measured under cooling and heating conditions. Bleached RBX as well as higher wax concentrations formed more viscous gels at low temperatures. Oil type showed less effect for the viscosity of the gels.
Rheological and Calorimetric Properties of Candelilla Wax and Dotriacontane Organogles. J.F. Toro-Vazquez1, J. Morales-Rueda1, E. Dibildox-Alvarado1, M.A. Charó-Alonso1, R. Weiss2, 1Universidad Autónoma de San Luis Potosí, San Luis Potosí, SLP, México, 2Gergetown University, Washington, USA
The main component of CW is hentriacontane, a n-alkane (C31H64) with self assembly properties in organic solvents. We have shown that independent of the cooling rate and gel setting temperature (Tset), CW develops thermoreversible organogels with vegetable oils. However, the structural organization of CW organogels depend on the cooling rate, the thermodynamic drive for gelation, and the annealing at high Tset. To investigate these events, we evaluated the rheological (G'), thermal, and microstructural properties of CW organogels (1%, 3%) in safflower oil at Tset's of 5°C and 25°C using two cooling rates (1°C/min, 10°C/min). The results were compared with the ones obtained with organogels of pure dotriacontane (C32H66) in safflower oil. At both cooling rates, the gelation (Tg) and the melting (Tp) temperatures were higher with dotriacontane (Do) than with CW. In both systems studied Tg was higher at 1°C/min than at 10°C/min but Tp was not affected by the cooling rate. Independent of the gelator concentration, at 5°C higher G' was obtained with CW organogels than with Do organogels, and this difference was more evident at 10°C/min. However, at 25°C organogels with Do showed higher G' than CW particularly at 1°C/min. This behavior was associated to microstructural differences as affected by the fractional gelation of CW components as function of Tset.
Diacylglycerol Oil Synthesis from Palm-Based Fatty Acids Using a Novel Heterogenous Catalyst. S.K. Lo1, L.Z. Cheong1, C.P. Tan1, K. Long2, M.S.A. Yusoff3, O.M. Lai1, 1Universiti Putra Malaysia, Serdang, Selangor, Malaysia, 2Malaysian Agricultural Research and Development Institute, Kuala Lumpur, Malaysia, 3Golden Hope Research Centre, Banting, Selangor, Malaysia
Macroporous strongly acidic cation exchange resin was used as a new heterogenous catalyst for diacylglycerol oil synthesis from palm-based fatty acids. Palmitic and oleic acids from palm oil were esterified with glycerol to yield diacylglycerol oil. Various reaction parameters were investigated and optimized using response surface methodology. The following optimized conditions yielded approximately 40 wt. % 1,3(2)-DAG and 4.7 wt. % triacylglycerol (TAG): reaction temperature of 110 °C, catalyst dosage of 24.8 wt. %, fatty acid/glycerol molar ratio of 3.0 and reaction time of 1.5 h. Results were repeatable in a 10 kg pilot packed-bed reactor. No significant losses in catalytic activity or changes in fatty acid selectivity were observed during the five pilot productions. The catalyst showed high selectivity towards the oleoyl moiety of 1,3(2)-DAG.
Amphiphilic Biopolymer Hybrids for the Improved Stabilization of Double Emulsions as Delivery System. R. Lutz, A. Aserin, N. Garti, Casali Institute of Applied Chemistry, Institute of Chemistry, Faculty of Science, The Hebrew University of Jerusalem, Jerusalem, Israel
Double emulsions (DEM), in spite of their theoretical potential as controlled release vehicles, are not widely used, chiefly due to their inherent instability. We present a new aqueous blend of two charged biopolymers, WPI and modified pectin (MP) that forms molecular conjugated hybrids capable of improving the DEM stability. At low pH ranges, the zeta potentials of the blend WPI/MP 4:0.5 wt/wt are lower than those additively co-operative calculations. The difference between the measured and the calculated zeta potentials indicates conjugation. The WPI self-diffusion coefficient of WPI in solution of WPI/MP 4/0.5 and in DEM is smaller by a factor of 1.5 as compared to pure WPI. The further decrease indicates on formation of conjugated hybrids. DEM droplets stabilized with WPI/pectins are three times smaller than droplets stabilized only with WPI (~15 μm for WPI/pectin and ~20 μm for WPI). All the DEM (WPI/pectins) droplets are about 15 μm and were stabilized to coalescence for at least 40 days. However, there are differences between the creaming and flocculation stabilities. The DEM stabilized with WPI/high methoxy pectin creamed faster than those stabilized with WPI/apple pectin while those stabilized with WPI/MP showed the lowest creaming. The differences are probably, due to the electrostatic nature of the pectin.In conclusion, new hybrid of WPI/MP improved significantly the DEM.
EAT 5: General EAT
Chair(s): G. List, USDA ARS NCAUR, USA
Development of the Australian Olive Industry. R. Mailer , Australian Oils Research Laboratory, Wagga, NSW, Austrailia
The Olive Industry is relatively new to Australia. Although olives were planted soon after the first settlement in Australia there has been little further development until recent years. The first olive plantings occurred in 1805. By 1891 State Governments had begun developing experimental groves such as the one still in existence at Wagga Wagga, NSW. This grove includes 54 Spanish, Italian and French olive cultivars and has been the source of tree cuttings for much of the rapid industry development in recent years. The revival of the industry occurred in the 1990's with a workshop and ultimately the establishment of the Australian Olive Association (AOA). Scientists from the International Olive Council (COI) were brought to Australia to help develop olive quality. They determined that some of the quality attributes of the oil did not meet international standards. Further investigation showed Australian oil was different in many of the characteristics described by COI for olive oil, particularly sterols and fatty acids. It was found that this variation was not unique to Australia but an issue for South America, New Zealand and even some oils produced in Mediterranean countries. Codex Australia has been pursuing these issues with Codex Alimentarius to ensure that international standards recognise the natural variability of products produced in different environments. The issue of standards, initially designed for products from traditional growing countries, has become of international interest with ongoing discussions for standards to allow for natural variation. Recently the USDA has released a draft set of standards that reflect these issues which are of critical importance to Australia where 50% of the oil produced is now being exported and production in 2008 has already reached 14,000 t.
Analytical Characterization of Rice (Oryza Sativa) Bran Oil from Different Agroecological Regions of Punjab. S.A.S. Chatha, F. Anwar, M.A. Sheikh, Department of Chemistry, University of Agriculture, Faisalabad,Punjab, Pakistan
In view of growing need and consciousness about the nutritional and functional properties of vegetable oils, analytical characterization of non-conventional oil seed crops is of much concern to cope the existing challenges. The present research work was aimed to characterize rice (Oryza sativa) bran oil from different agroecological regions of Punjab. The investigated rice bran was found to contain oil, protein, fiber and ash contents in the range of 13.92-19.81, 15.30-17.60, 7.64-9.65 and 7.50-9.50%, respectively. Physical and chemical parameters of the hexane-extracted rice bran oils were as; density (40 0C) 0.909-0.921mg/cm3, refractive index (40 0C) 1.4586-1.4596, iodine value 103.75-113.15 g of I2/100 g of oil, peroxide value 2.47-3.20 meq/kg, acid value 40.39-45.01%, p-anisidine value conjugated diene contents 2.01-3.11 and conjugated triene contents 0.89-1.01. Furthermore the rice bran oil was found to contain C16:0, C18:0, C18:1 and C18:2 as major fatty acids and Î±, ï§ and ï¤ tocopherols and tocotrienols in its composition. Rice bran and rice bran oil has many physio-chemical, nutritional and compositional properties fairly comparable to those with the conventional vegetable oils, being used as an important constitute of human diet and other commercial purposes.
Lipase Catalysed Esterification for the Production of Oleochemicals. G. A. Usmani, H. V. Patil, North Maharashtra University, Jalgaon, India
Non-traditional oils which are not used for edible purpose are to be converted into value added products. Thus esterification of such oils catalyzed by lipase to produce oleochemicals is carried out in present work. Conventional chemical method of esterification has got several problems which are to be overcome by proposed work using enzymatic catalyst. Enzyme catalyzed process is eco-friendly; less expensive. Besides these it has one more advantage of selective action of enzyme to produce desired product. Here, esterification is catalyzed by different enzymes for comparative studies. Non traditional oils like Neem, Karanja, and Rice bran are used to produce the oleo chemicals.
Lipid Oxidation and Antimicrobial Activity of Polyphenols. T. Rojanasasithara1, P.M. Davidson2, E.A. Decker1, J. Weiss1, 1Department of Food Science, University of Massachusetts Amherst, Amherst, MA, USA, 2Department of Food Science and Technology, University of Tennessee, Knoxville, TN, USA
Lipid oxidation results in unacceptable quality of foods. Phenolic compounds in essential oil (EO)and plant extracts possess antioxidant and antimicrobial activities. Interest in the use natutal phenolic compounds as part of their product formulation has increased in order to preserve both food quality and ensure food safety. However, it is not clear whether oxidation of compounds may lead to loss of antimicrobial activity. The objectives of this research were to study how lipid oxidation effects antimicrobial activity of phytophenols. We present results of two studies where this relationship was investigated. First, antimicrobial efficacy was determined by microbroth dilution assays and antioxidant activity of simple phenols (EO) subjected to oxidative conditions. Compounds exhibited very high oxidative stability and antimicrobial activity after DPPH treatment. We further present results of antioxidant and antimicrobial activity of polyphenolic compounds (cranberry extract) showing a remarkable similarity in increases in antioxidant and antimicrobial activity based on the polarity and surface activty of the extracted fraction. Results suggest surface activity of compounds plays a key role in antimicrobial and antioxidant activity due to the need to either insert in bacterial membranes or catalyze reactions at oil-water interfaces.
Effects of a Membrane-Permeable Metal Chelator on Iron-Mediated Lipid Oxidation in Washed Fish Muscle. P. Kathirvel, M.P. Richards, University of Wisconsin-Madison, Madison, Wisconsin, USA
The specific mechanisms by which iron promotes lipid oxidation in biological membranes remains poorly understood. Part of this can be attributed to a lack of knowledge pertaining to iron partitioning between aqueous, oil, protein and membrane phospholipid phases in tissues. We have observed that aqueous iron chelators (e.g. ADP and EDTA) did not promote iron-mediated lipid oxidation in washed fish muscle substrate. The ability of tetrakis-(2-pyridylmethyl) ethylenediamine (TPEN) to promote iron and hemoglobin-mediated lipid oxidation in washed cod was examined. TPEN has relatively low water solubility and it was thought this may deliver iron to the membrane and thereby facilitate iron-mediated lipid oxidation. Lipid peroxides and thiobarbituric acid reactive substances (TBARS) were measured during 2°C storage. TPEN promoted lipid oxidation in washed cod alone, presumably due to binding of trace metals contaminating the substrate. TPEN promoted iron-mediated lipid oxidation while aqueous iron chelators were not effective. TPEN also accelerated hemoglobin-mediated lipid oxidation in washed cod. In solution, addition of excess EDTA did not disrupt the Fe-TPEN complex which suggested a relatively strong binding affinity of TPEN for iron. The probable mechanisms by which TPEN promoted lipid oxidation in washed cod muscle are discussed.
Marine Omega-3 Enhanced Food, An Enormous Potential for Better Public Health. M. Bockisch, Berlin Technical University, Department of Food Technology, Germany
It is beyond any doubt that long chain marine omega-3-fatty acids represent an enormous potential to improve public health. Numerous observational studies, statistics and several clinical trials prove these benefits. Usually the required supply is not met by the diet and liver which can produce these fatty acids is not very efficient. That is which is why supplementation is beneficial and unanimously recommended.Especially children and the elderly require sufficient supply â€“ for development and maintenance of important body functions. Major health benefits are in pregnancy outcome, eye and brain development and health, the metabolic syndrome and in easing inflammatory processes. Prevention of diseases such as Alzheimer and dementia is discussed and there is statistical evidence for protection against cancer and for a reduction of behavioural problems.To offer food at a quality which is accepted by consumers high skills in sourcing and preparation of the raw materials as well as in processing are required. Overcoming the problem of low oxidative stability is important for an acceptable taste and sufficiently long best before dates.Special problems are claims that can (not) be made on pack and finding the right communication towards parents and especially towards the elderly.
Novel Production of Diacylglycerol-Enriched Palm Olein by Lipase-Catalyzed Partial Hydrolysis for Binary Nutraceutical Shortening Systems. L.Z. Cheong1, S.K. Lo1, N. Arifin1, C.P. Tan2, K. Long3, M.S.A Yusof4, O.M. Lai1, 1Universiti Putra Malaysia,, Serdang, Selangor, Malaysia, 2Universiti Putra Malaysia, Serdang, Selangor, Malaysia, 3Malaysian Agricultural Research and Development Institute, Kuala Lumpur, Malaysia, 4Golden Hope Research Centre, Banting, Selangor, Malaysia
Diacylglycerols (DAGs) are functional lipids that are able to reduce obesity and risk factors of metabolic syndrome. A novel single step lipase-catalyzed partial hydrolysis process on a pilot scale bioreactor setting has been successfully optimized to produce a diacylglycerol-enriched palm olein (PDG) with a purity of at least 60 wt %. This process can be conducted continuously for at least ten consecutive batches without significant loss of enzymatic activity. PDGs produced from this technology were blended with palm stearins (PS) of different IVs (IV25 and IV40) to produce binary shortening systems. Interactions of fats in the binary systems were studied using phase behavior diagrams and isosolid diagrams constructed from pulse-NMR and DSC data. Microstructure and polymorphism of the fat systems were determined using a polarized light microscopy. Hardness was measured using cone penetrometer. Results suggested a high degree of structural complementarity between PDGs and PS IV25. Eutectic behavior was observed in the binary blends of PDGs and PS IV40 at approximately 40 wt % PDG. Formulated binary systems of PDGs with PS of different IVs were comparable with commercial shortenings in terms of microstructure, polymorphism, hardness and baking performance.
Edible Applications Technology Posters
Chair(s): M. Tulbek, North Dakota State University, USA
Kinetic Behavior of Sunflower Oil Lipase-Catalyzed Acidolysis.
C. Pacheco, A. Carelli, M.E. Carrín, PLAPIQUI (UNS - CONICET), Bahía Blanca, Argentina
During enzymatic acidolysis a desired acyl group is incorporated onto a specific position of the triacylglycerol to produce structured lipids (SL). In the present study, sunflower oil (SO) was modified with a palmitic-stearic acids blend (FFA) by using an immobilized sn-1,3 specific lipase: Lipozyme RM IM (from Rhizomucor miehei, immobilized on ion-exchange resin). Experiments were performed as follow: substrates and solvents were preheated in a water bath; adding lipase started the reaction, which was carried out at a laboratory scale in a close system with agitation; to stop the reaction, mixture was filtered.Changes in SL composition were determined through deacidification by alkaline extraction, FAME preparation by cold transesterification, and further analysis by capillary gas chromatography (CGC). Deacidified products were analyzed to quantify by-products as glycerol (G), monoglycerides (MG) and diglycerides (DG) by silylation and CGC determination. Nonlinear regression methods were employed to determine kinetic parameters of the enzymatic mechanism representing the reaction from the initial stage until equilibrium. The effects of the reaction conditions (temperature, time, incorporated water) on enzymatic acidolysis were studied. DG formation and kinetic and equilibrium parameters showed temperature dependencies. MG formation was not observed.
Organogelation of Candelilla Wax in the Presence of High Melting Triacylglycerides.
J.F. Toro-Vazquez, M. Alonso-Macias, J.A. Morales-Rueda, E. Dibildox-Alvarado, M.A. Charó-Alonso, Universidad Autónoma de San Luis Potosí, Facultad de Ciencias Químicas, San Luis Potosi, SLP, México
We investigated the development of a solid phase in dispersions of candelilla wax (CW; 0.5% to 3.0%) in safflower oil (SFO) with and without tripalmitin (TP). The development of a solid phase (i.e., organogel) by the CW components at different temperatures (Tset) was followed by DSC, microscopy, rheometry, and texture measurements using in all cases a cooling rate of 10°C/min. The results showed that organogelation of CW occurred at temperatures above the crystallization temperature of TP (TCr). Nevertheless, under isothermal conditions at Tset above (i.e., Tset = -5°C or 15°C) the TCr of tripalmitin in SFO, the TP crystallized on the organogel structure. The TP crystallization modified the original three-dimensional structure of the organogel with the subsequent effect on the elastic modulus (G′), shift angle (δ), yield stress (σ*), and hardness of organogels. In general, CW organogels developed at Tset of -5°C and 15°C in the presence of 1% TP showed higher G′ than organogels developed in the absence of TP. However, the σ* was higher in CW organogels developed without TP than in organogels developed in SFO with 1% TP. This regarless the higher SFC present in the systems with TP. Similar results were observed by hardness. These results showed that crystallization of high melting TAGS modifies the functional properties of organogels in vegetable oils.
Fatty Acid Profile and Physicochemical Analysis of Olein and Stearin Fractions from Crude Palm Oil Produced in Tabasco, Mexico.
L.F. Trujillo Castillo1, J.R. Velázquez Martínez1, M. Yanes García1, J.R. López Aguilar1, L.A. Médina Juárez2, 1Universidad Juárez Autónoma de Tabasco, Villahermosa, Tabasco, México, 2Universidad de Sonora, Hermosillo, Sonora, México
The African palm (Elaeis guineensis) is a crop of recent introduction in Mexico. The obtained crude oil of the african palm gathers several important characteristics for the utilization in the diet. Analysis of physicochemical characteristics and fatty acids profiles of its two main fractions, olein and stearin, was carried out. Physicochemical characteristics of the two fractions were analyzed using the methods of the AOCS. Fatty acids profile was determined by means of Gas Chromatography (AOCS Cd 8-53). The best conditions of separation were achieved heating the oil to 70ºC and then cooling the oil to 30 ºC for the crystallization during 12 hours obtaining around 61% of olein and 39% of stearin. Physicochemical characteristics of the two oil fractions were acceptable to consider them for the human consumption except for its acidity; the fatty acids profile showed that olein fraction contained 46% and 52% and the stearin fraction 61% and 37% of saturated and unsaturated fatty acids, respectively. The fractions of olein and stearin obtained from crude palm oil possess an adequate fatty acids profile for human consumption and characteristics for its utilization in food industry. Only acidity exceeds the permitted level for consumption, for which is required an adequate deodorization to improve the quality of the fractions.
Alkyl Esters of Fatty Acids-A Useful Tool to Detect Soft Deodorized Olive Oils.
M.D.C. Pérez-Caminoa, W. Moreda, C. Cert, Instituto de la Grasa (C.S.I.C.), Spain
Fatty Acid Alkyl Esters (FAAEs) are a family of natural neutral lipids present in olive oils and formed by esterification of Free Fatty Acids (FFA) with low molecular alcohols. Inappropriate practices during the olive oil extraction process and bad quality of the olive fruits promote their formation. Quantification can be done by isolation with silica gel solid phase extraction cartridge followed by analysis on a gas chromatograph equipped with programmed temperature vaporizer injector using a polar capillary column. The application of the method to olive oils from different categories, varieties and geographical origin allowed establishing the average content of FAAEs in extra and virgin olive oils and distinguishing from low quality olive oils. Low quality oils can be subjected to mild refining process, allowing their blends with extra virgin olive oils. Studies on oils subjected to mild refining showed that these compounds remain after refining. Thereby, blends of extra virgin olive and mild refined low quality olive oils can be detected by their alkyl esters concentrations.
Evaluation of Milled Flaxseed and Flaxseed Oil on the Oxidative Stability of Bean Paste.
Mehmet Tulbek1, Clifford Hall III2, 1Northern Crops Institute, Fargo, ND, USA, 2North Dakota State University Department of Cereal Science, Fargo, ND, USA
Bean paste is a staple food mainly consumed as a ready to eat product in US. Flaxseed oil is the main source of omega-III fatty acids, which can be supplemented to cereal products. The objectives of this research were i) to develop a flaxseed oil fortified bean paste process; ii) to determine the effects of flaxseed oil on bean paste quality and shelf life stability; and iii) to determine nutritional analysis of bean paste. Bean paste was developed according to a bench top scale frying process. Bean flour (46.4 g.) was fried with canola oil (22.3 g.) for 5 min. Bean paste was stored at fridge for 24 h. for further shelf life quality evaluation. Shelf life stability of bean paste was evaluated by headspace volatile analysis. Gas chromatography was conducted and secondary metabolites of lipid oxidation were analyzed. Propanal the primary aldehyde of alpha-linolenic acid was not detected in bean paste samples at 3 day storage at ambient conditions. Bean paste samples were refrigerated and paste quality did not deteriorate in 8-week storage. Results indicated no lipid oxidation due to flaxseed oil addition. In conclusion bean paste can be fortified with flaxseed oil. Bean paste is a stable product with excellent texture and pasting properties, which can be preserved in refrigerator for storage.