Effects of storage on physico-chemical parameters and quality of Greater Rhea (Rhea americana) eggs

The Greater Rhea (Rhea americana) is a member of Brazilian fauna with potential for the production of eggs with a unique nutritional composition that differs from the eggs of other species. The present study aimed to gather information regarding the centesimal composition of Greater Rhea eggs and the storage time for the preservation of egg quality for human consumption. Twenty-five Greater Rhea eggs (albumen and yolk fractions), distributed into five groups of eggs stored for 7, 14, 21, 28 and 35 days at 10 degrees C, were analysed. For the determinations of the percentage composition, total protein was quantified by the Kjeldahl method and total lipids by the Soxhlet method. To assess egg quality, the Haugh unit (HU), pH, and protein degradation (by SDS PAGE electrophoresis) were determined. Based on the results, the albumen protein fraction quality was maintained for 21 days, while the yolk proteins began to denature on the 14th day. The total lipids of the albumen and yolk fractions did not change significantly until the 35th day of storage; at this time, the quality decreased significantly, indicating that the eggs were adequate for consumption until the 28th day. Considering the protein degradation profile and internal quality, Greater Rhea eggs can be stored for 21 days at 10 degrees C without alteration of their nutritional or functional characteristics.