Performing Department
(N/A)
Non Technical Summary
Consumers' demands for egg white due to its fat-free, protein-rich nature have significantly increased the production of processed egg products. However, the utilization of its counterpart, egg yolk, has been considerably restricted because of its high lipid and cholesterol contents and limited functionalities. The imbalanced utilization of processed egg products becomes a threat to the sustainability of the egg industry and price stability for consumers. Therefore, novel ways should be developed to improve its functional and nutritional properties and consequently increase the utilization of egg yolk. One of the promising approaches is to employ fractionation technology to produce egg yolk fractions with unique functional and nutritional characteristics. Our long-term goal is to develop novel functional and nutritional food ingredients from egg yolk to increase its use and value. This project will develop novel, environmentally friendly, readily industry-applicable, cost-effective fractionation technology for egg yolk and produce distinctive egg yolk fractions with enhanced nutritional and functional properties as novel food ingredients, using physical, chemical, and enzymatic treatments. The fractionation technologies utilized in this project will be simple, economical, easy to scale up, no use of organic solvents, and use of chemicals compatible with human food, and compatibility for a sequential separation of egg yolk functional components, and their operational conditions will be optimized to produce egg yolk fractions. Subsequently, their functional and nutritional properties will be enhanced using high-temperature-mild-pressure treatment and enzyme hydrolysis. Developing novel food ingredients from egg yolk in this project will contribute to balancing the use of egg white and yolk, and consequently improving the sustainability and competitiveness of the egg industry and the price stability of egg white for food manufacturers and consumers.
Animal Health Component
100%
Research Effort Categories
Basic
0%
Applied
100%
Developmental
0%
Goals / Objectives
The overall goal of this project is to develop novel, readily applicable, cost-effective, environment-friendly, consumer-friendly fractionation technology in combination with mechanical and enzymatic modifications and produce distinct egg yolk fractions as novel food ingredient commodities with unique functional and nutritional properties and bioactive functions. To accomplish this goal, we propose 3 specific objectives:1. Develop and optimize fractionation technologies to fractionate egg yolk into 4 distinct fractions with unique functional and nutritional characteristics.2. Modify the fractions using physical, chemical, and enzymatic treatments to improve their functional and nutritional properties.Determine the physicochemical, functional, nutritional, and structural characteristics of the egg yolk fractions and their applicability to the food products
Project Methods
The development and optimization of fractionation technologies to fractionate egg yolk into 4 distinct fractions will be conducted to achieve Objective 1. The modification of the fractions to improve their nutritional and functional properties will be conducted to achieve Objective 2. Pressurized heat and enzyme treatments alone and in combinations will be used to modify the fractions obtained in Objective 1. The physicochemical, functional, nutritional, and structural characteristics of the fractions prepared in Objectives 1 and 2 and their applicability to the food products will be determined to achieve Objective 3. The functional characteristics (emulsifying, gelling, and foaming properties) of the egg yolk P, LDL, and Livetin fractions and their hydrolyzed products will be evaluated and compared. Foaming capacity and stability will be determined as the specific density of the foam and the volume of drainage released from the foam 30 min after the foam is made using a mixer with a wired whip. Protein solubility will be determined using centrifugation, surface hydrophobicity using a fluorescence probe, and sulfhydryl contents using Ellman's reagent. Emulsification properties will be evaluated by determining emulsification capacity and emulsion stability. For gelling properties, the fraction solutions will be heated in cylindrical tubing at 100 °C for 18 min to produce their gel. Color, water holding capacity, and texture profile analysis of the gel will be determined using a colorimeter, centrifugation, and texture analyzer, respectively. Nutritional values (proximate composition, protein/lipid/amino acid/fatty acid compositions, and cholesterol and carotenoid contents) of each fraction will be determined. Granules and its fractions and their modified counterparts will be tested for their emulsifying, foaming, and gelling properties, and nutritional values as above. The amount and type (peptide size, amino acid sequence) of phosvitin phosphopeptides in the modified PR fraction will be determined using SDS-PAGE and tandem mass spectrometry. The calcium-binding capacity The modified PR fraction will be determined using ion-selective electrodes and iron- and copper-binding capacities using the spectrophotometric method. The antioxidant capacity will also be determined using oxygen radical absorbance capacity (ORAC) analysis. Phospholipase-hydrolyzed PL-rich fraction will be tested for its emulsifying and encapsulating capacities. In addition, the applicability of the fractions and their modifications to the model food systems will be determined. Three model food products will be utilized to evaluate the applicability of the egg yolk fractions and their modifications to the production of food products: mayonnaise, angel food cake, and beef patty. The applicability of the fractions and their modifications produced from Objectives 1 and 2 will be evaluated as substitutes for liquid egg yolk in the production of mayonnaise. Mayonnaise's quality parameters such as pH, color, stability at different temperatures, texture (firmness and adhesiveness), and rheological properties such as storage and loss modulus to determine flow behaviors using a rheometer will be determined. The applicability of the fractions and their modifications produced from Objectives 1 and 2 will be evaluated as substitutes for liquid egg white and egg white powder in the production of angel food cake. The quality parameters of angel food cake will be determined: cake color, volume, moisture content, cross profile image, and texture profile using a texture analyzer. For the beef patty, coarsely ground beef (80% lean) will be mixed with Livetin, and PR fractions and their modifications in addition to water, salt, and onion powder. Beef patties with no added proteins and soy protein powder will be of negative and positive controls, respectively. Quality parameters of beef patties will be measured: pH, color, moisture loss of raw patties, cook yield, lipid oxidation, texture profiles, and shear force. Data will be analyzed using the ANOVA procedure with Student-Newman-Keuls' multiple-range test (P < 0.05) for mean comparison. Egg yolk fractions and their modified counterparts will be produced at Iowa State University (ISU). They will be lyophilized and shipped with ice to the University of Maryland Easter Shore (UMES) to determine their functional, biological, and nutritional properties. The PD and co-PDs will comply with UMES, the University System of Maryland (USM), ISU, and federal regulations involving the nature and scope of this project.?