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.
Evaluation of Quality and Nutrient Contents of Table Eggs from Different Sources in the Retail Market
Table egg quality and nutrient contents from four sources in the retail market in Jeddah city, Saudi Arabia were evaluated using straight run experimental design and compared with the recommended daily allowance (RDA, 2002/2005) profiles. Egg source had a noticeable effect (P<0.05) on shell weight per unit of surface area, albumen percentage, Haugh unit, yolk percentage, index and colour. Differences in dry matter, protein, and lipid profiles of eggs were significant (P<0.05) among various sources, while variability in egg cholesterol and low density lipoprotein reached 51 and 17.6% (P<0.05), respectively. Egg sources had an effect (P<0.05) on total antioxidant capacity and lipid malonaldehyde. Mineral contents (mg/egg) of the whole edible parts of eggs showed a significant difference (P<0.05) among different egg sources in most of the minerals except for potassium. In conclusion, eggs in the retail market had variable quality and nutrition contents that may affect the fulfillment of the RDA for human and may possibly improve the quality of eggs and their nutritional values. Such diversity indicates the need for uniform of production and husbandry practice, the enforcement of quality control regulations based on egg quality and nutrient profiles by the authorities in the market, and the impact this may have on the health of the consumer.
Experimental study of thermal modeling for stratospheric platform airships
R&D work on the Japanese stratospheric platform airship is discussed from the viewpoint of the thermal modeling. The work includes two experiments on the thermal characteristics of the 25m-long airship and the 35m-long PV-equipped airship model. The validity of the current thermal model was confirmed by comparing the calculated results with the measured data. The other important work is the Ground-to-Stratosphere (GTS) flight test. A 47mlong airship-shaped balloon was flown to the stratosphere. The flight simulation program into which the thermal model was integrated, was developed and applied successfully to predict the ascent behavior and the flight trajectory.