The major driving force for the egg consumption in the United States over the past few decades was processed egg. However, the consumption of egg through the processed egg reached the plateau in ...recent years because of the imbalance in the demands between the egg white and yolk products. The consumer demands for egg white products are very high while those for the egg yolk, the co‐product of dried egg white, are low because of the negative perceptions on egg yolk. Two key approaches that can be used to increase the value and use of egg yolk are: (1) developing new commodity products by fractionating egg yolk and apply them in various food processing, and (2) separating functional proteins and lipids from yolk and use them as is or further develop functional peptides and functional lipids and use them as pharmaceutical, nutraceutical, and cosmeceutical agents. These approaches can diversify the use of egg yolk, which eventually will help increase the consumption of egg. This review (1) discusses the current use of egg yolk products and the development of new functional commodity products from egg yolk, (2) review the important functional components in egg yolk and overview the current separation methods and their applications, (3) discuss the production of functional peptides and lipids using the separated egg proteins and lipids, and (4) suggest the future directions for the best use of egg yolk components. Development of scale‐up production methods, which is vital for the practical applications, is discussed when appropriate.
The objective of this study was to determine the effects of various levels of dietary black cumin seed on egg production, egg weight, feed conversion ratio, egg shell quality, and egg yolk ...cholesterol. In this study, eighty 27-wk-old laying hens (Hyline-5 White) were randomly assigned into 4 groups with 4 replicates of 5 birds each (20 laying hens per group) and fed diets supplemented with 1, 2, or 3% black cumin. Eggs were collected and weighed daily. Laying performance, egg quality, and feed conversion ratio were evaluated. Laying hens fed the diet supplemented with 3% black cumin had greater egg production than the control. Diets supplemented with 2 or 3% black cumin increased egg weight compared with other groups. Yolk weights of the eggs from hens fed diets containing 1, 2, and 3% black cumin were significantly greater than those from the control group. Shell thickness of the eggs from chickens fed 2 or 3% black cumin seed was significantly greater than those from chickens fed diets supplemented with 0 or 1% black cumin seed. Also, shell strength of the eggs from hens fed diets supplemented with 3% black cumin seed was significantly greater than the control. In addition, diets supplemented with 2 or 3% black cumin significantly decreased egg cholesterol per gram of yolk compared. No level of black cumin seed supplementation had any effect on live weight, feed consumption, feed conversion ratio, organ weights, and abdominal adipose tissue. This study showed that black cumin at the level of 2 or 3% would positively influence egg production, egg weight, and shell quality and decrease the concentration of cholesterol in the egg yolk.
BACKGROUND: The objective of this study was to determine the effects of dietary yeast autolysate on performance, egg traits, egg cholesterol content, egg yolk fatty acid composition, lipid oxidation ...of egg yolk, some blood parameters and humoral immune response of laying hens during a 16 week period. A total of 225 Hyline Brown laying hens, 22 weeks of age, were allocated equally to one control group and four treatment groups. Yeast autolysate (Saccharomyces cerevisiae, InteWall) was used at levels of 1, 2, 3 and 4 g kg⁻¹ in the diets of the first, second, third and fourth treatment groups respectively.RESULTS: Dietary treatments did not significantly affect body weight, feed intake and egg traits. Yeast autolysate supplementation increased egg production (P < 0.001) and egg weight (P < 0.001) and improved feed efficiency (P < 0.05). Yeast autolysate at levels of 2, 3 and 4 g kg⁻¹ decreased egg yolk cholesterol level as mg g⁻¹ yolk (P < 0.01) and blood serum levels of cholesterol and triglyceride (P < 0.05) and increased antibody titres to sheep red blood cells (P < 0.01). Total saturated fatty acids and the ratio of saturated/unsaturated fatty acids increased (P < 0.01) and total monounsaturated fatty acids (P < 0.001) decreased with yeast autolysate supplementation.CONCLUSION: Dietary yeast autolysate at levels of 2, 3 and 4 g kg⁻¹ had beneficial effects on performance, egg cholesterol content and humoral immune response. It is concluded that 2 g kg⁻¹ yeast autolysate will be enough to have beneficial effects in laying hens. Copyright
Can food processing produce hypoallergenic egg? Ma, Xiaojuan; Liang, Rui; Xing, Qianlu ...
Journal of food science,
September 2020, 2020-Sep, 2020-09-00, 20200901, Letnik:
85, Številka:
9
Journal Article
Recenzirano
Odprti dostop
Eggs and their derived products are common foods that can induce food allergic reaction, especially in children. The reported incidence of egg allergy is 1% to 2%, and its prevalence has rapidly ...increased in recent years. Currently, there is no approved treatment for it. The clinical guidance for this adverse food reaction is the complete elimination of egg (and their derived products) from diet, which is difficult due to the wide use of egg ingredients in food industry. Food processing methods can affect the conformational and/or linear epitopes of allergens and may change the allergenicity of egg. Thermal treatment and various other processing methods based on the enzymatic hydrolysis and irradiation have been found useful in reducing allergenicity of certain egg allergens. However, processed egg proteins can also show an increased allergenicity after treatment and the correct pattern to follow for the generation of hypoallergenic products remains unclear. This review explores the influence of processing methods on egg allergenicity and reports the best options for the generation of hypoallergenic egg products to date.
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