Jump to Main Content
Effects of Different Rearing and Feeding Systems on Lipid Oxidation and Antioxidant Capacity of Freeze-Dried Egg Yolks
- Pignoli, Giovanni, Rodriguez-Estrada, Maria Teresa, Mandrioli, Mara, Barbanti, Lorenzo, Rizzi, Laura, Lercker, Giovanni
- Journal of agricultural and food chemistry 2009 v.57 no.24 pp. 11517–11527
- rearing, poultry production, hen feeding, lipid peroxidation, antioxidant activity, freeze drying, dried eggs, egg yolk, food analysis, food composition, nutrient content, nutritive value
- Lipid oxidation and antioxidant capacity of freeze-dried egg yolks produced with two rearing systems (battery cages and free-range) and two types of feedings (conventional and organic) were studied. Nine fresh egg yolks of each crossed treatment were pooled, frozen for a month, freeze-dried, vacuum-packed, and kept at −18 °C until analysis. No significant differences were observed in the lipid (58.0−62.1%) and total sterol contents (33.0−35.5 g/kg of lipids) of the freeze-dried egg yolks. Free rearing and conventional feeding systems resulted in significantly higher total tocopherol, α-tocopherol, and lutein contents, as compared to the battery cage and the organic feed, respectively. However, no significant differences were found in lipid oxidation (peroxide value = 0.7−0.9 mequiv of O2/kg of fat; thiobarbituric reactive substances = 1.0−1.3 mg of malonylaldehyde/kg of sample) and cholesterol oxidation (28.8−43.5 mg of cholesterol oxidation products/kg of lipids; 0.08−0.12% oxidized cholesterol) of freeze-dried egg yolks except for 7α-hydroxycholesterol, which was significantly lower in samples obtained with organic feed.