Selected quality and shelf life of eggs coated with mineral oil with different viscosities.

Selected quality and shelf life of eggs coated with mineral oil having 6 different viscosities (7, 11, 14, 18, 22, and 26 cP) were evaluated during 5 wk of storage at 25 degrees C. As the storage time increased, weight loss and albumen pH increased whereas Haugh unit and yolk index values decreased. After 5 wk of storage, eggs coated with 11, 14, 18, 22, or 26 cP oil possessed better quality than the control noncoated eggs and eggs coated with 7 cP oil. Oil coating, irrespective of viscosities, did not improve the emulsion capacity. There was an observable trend that coating with 26 cP oil was more effective in preventing weight loss and in maintaining the Haugh unit of eggs compared with coating with other viscosities of mineral oil. Based on the Haugh unit, the grade of noncoated eggs changed from "AA" at 0 wk to "C" after 3 wk whereas that of 26 cP oil-coated eggs from "AA" at 0 wk to "A" at 3 wk and "B" at 5 wk of storage. Coating with 26 cP oil reduced the weight loss of eggs by more than 10 times (0.85% compared with 8.78%) and extended the shelf life of eggs by at least 3 more weeks compared with the noncoated eggs.