The Level of Fat- and Water-Soluble Antioxidants in Eggs of Free-Range Geese during a Production Season

Abstract

In this investigation, egg yolk and egg white water and fat-soluble antioxidant concentrations of geese eggs were determined during a production season according to months and weeks. Breeders consumed 100 g commercial layer feed per day during a production season. The farm was located at a semi-open prison of the Ministry of Justice in Van city. Fat-soluble (vitamin A, E, total and individual carotene) of egg yolk and water-soluble (ascorbic acid and GSH) antioxidants of egg white of geese were measured in February, March, April and May per week gazed in pasture conditions. Roche Yolk Color Fun (RYCF) values and Minolta (L* brightness, a* redness, and b* yellowness) values varied according to months and statistically significant differences were observed (p <0.05). RYCF, a * redness, and b *yellowness values were the lowest in February and L* brightness values were the highest in February (p <0.001). According to months (February-May), the egg yolk concentration of vitamin A (retinol) were 3.05±0.11, 1.84±0.10, 1.93±0.09, 2.84±0.19 µg g-1, total vitamin E were 26.87±1.80, 25.07±1.64, 38.16±1.71, 34.30±1.89 µg g-1, and total carotene were 15.49±1.44, 19.50±1.79, 42.39±1.99, 44.30±2.03 µg g-1 (p <0.05), respectively. In this study, lutein, cis-lutein, zeaxanthin, apoester, canthaxanthin, and beta-carotene were identified as individual carotene in goose egg yolks. Glutathione (GSH) and Vitamin C or ascorbic acid (AA) were detected in geese eggs white in the last two weeks of February and four weeks of March, April, and May. The results were recorded as: 0.91±0.14, 1.83±0.19, 2.69±0.15, 1.97±0.09 µg g-1 for AA and 7.71±1.86, 33.22±2.14, 45.37±2.41, 38.75±1.50 µg g-1 for GSH respectively. Both water-soluble GSH and AA data were significantly lower in February and were significantly higher in April (p <0.05) compared to other months.