Stability of the pigmentation of egg yolks enriched with omega-3 and carophyll stored at room temperature and under refrigeration

The objective of this experiment was to study yolk pigmentation stability in omega 3 (ω-3) enriched eggs stored under different temperatures in zeaxanthin equivalent (by using visible light spectrophotometer) and visual score (with values obtained by yolk color fan) and to verify the correlation among those methodologies. Three hundred big eggs from Isa Brown hens were distributed into two lots each one containing 150 eggs, stored at room temperature (26.5ºC) or under refrigeration (7.9ºC) for 35 days. It was used a completely randomized design in a 2 × 6 factorial arrangement (storage temperature × storage period). Pigmentation observed with the yolk color fan was steady during the experiment period when eggs were kept under refrigeration and it reduced when stored at room temperature. At spectrophotometric quantification, carotenoids decreased in both temperatures studied. There is a high correlation between the methods of analysis for eggs stored at room temperature and for eggs stored under refrigeration as well, but this correlation is sharper when eggs are stored under refrigeration.