Internal quality and shelf life of eggs coated with oils from different sources.
UNLABELLED
Selected internal quality and shelf life of eggs coated with oils from differences sources (mineral oil, canola oil, corn oil, grape seed oil, olive oil, soybean oil, and sunflower oil) were evaluated during 5 wk of storage at 25 °C. As the storage time increased, weight loss increased whereas Haugh unit and yolk index values decreased. Throughout the 5 wk of storage, eggs coated with oils, regardless of oil sources, possessed better albumen and yolk quality than the control noncoated eggs. Oil coating minimized weight loss of eggs (<0.8%) compared with that (7.26%) of the noncoated eggs after 5 wk of storage at 25 °C. No significant differences in internal quality (weight loss, Haugh unit, yolk index, and albumen pH) were generally observed among oil-coated eggs during 5 wk of storage. Based on the Haugh unit, the grade of noncoated eggs changed from AA at 0 wk to A at 1 wk and to B after 3 wk whereas that of oil-coated eggs from AA at 0 wk to A at 4 wk and maintained A grade until 5 wk. This study demonstrated that oil coating, irrespective of oil sources, preserved the internal quality, minimized weight loss (<0.8%), and extended the shelf life of eggs by at least 3 wk longer than observed for the noncoated eggs at 25 °C storage. Soybean oil was a more practical option as a coating material for eggs due to its low cost.


PRACTICAL APPLICATION
Eggs are highly perishable and susceptible to internal quality deterioration when stored above 7 °C. Refrigeration of eggs may be seldom practiced in some developing regions of the world. Therefore, an alternative method, that is inexpensive yet effective, to preserve the internal quality of eggs and to prevent microbial contamination is needed. Oil coating has been proven to preserve the internal quality, prolong shelf life, and minimize weight loss of eggs. This study demonstrated that, compared with other vegetable oils, soybean oil was a more practical option as a coating material for eggs during 5 wk of storage at 25 °C due to its low cost.
Degradable wheat gluten films: preparation, properties and applications
Degradable films from spray-dried (SD) and flash-dried (FD) wheat gluten prepared at various pHs, salt levels, temperatures, and shearing times were compared. Differences were observed in properties of the films related to processing conditions. Films prepared from SD wheat gluten were thicker, and had higher tensile strengths and Young's moduli. SD wheat gluten solutions applied as coating material resulted in Grade A-quality shell eggs maintaining quality for 30 days at room temperature. Additionally, SD wheat gluten coating increased the water stability of starch-based packaging.
Gelation of Egg Yolk
SUMMARY 
A study of the effects of freezing and thawing on egg yolk showed that there was a rapid increase in viscosity (25°C) during the first few hours of storage at −10° and −14°C. The effectiveness of sucrose and of sodium chloride as inhibitors was determined, and the influence of urea on the viscosity of native and of frozen and thawed yolk was investigated. Paper electrophoresis indicated that freezing and thawing caused electrophoretic changes of the yolk lipoproteins.