| dc.description.abstract | The aim of this research was to determine the quality of eggs laid by Tetra SL hens fed standard diet (B) or diet supplemented with 100 mg vitamin E/kg+200 mg/kg lutein+0.5 mg/kg selenium+5% oil mixture (BK). The effect of treatment was determined for yolk color values (P<0.001), which were more intense in the BK group (14.35) than in the B group (12.20). Other egg quality indicators (egg mass, portions of albumen, yolk and shell, Haugh units, albumen height, egg shell thickness and strength, pH values of albumen and yolk) exhibited no statistically significant differences (P>0.05). However, the treatment had statistically significant effect (P<0.001) on yolk color values for fresh eggs (B=12.00 and BK=14.42), as well as for eggs cooked for 7 minutes (B=9.14 and BK=13.00) and for 10 minutes (B=7.28 and BK=8.42). There was statistically significant effect of treatment, cooking length and their interaction on yolk lightness (L*). This value increased in dependence on cooking length (treatment B) and consequently, for the same yolks, intensity of redness (a*) was decreased, while intensity of yolk lightness (L*) in BK treatment was varying. The L* value decreased for eggs cooked for 7 minutes, but increased significantly for eggs cooked for 10 minutes, if compared to fresh eggs (P<0.001). The values of egg yolk lipid oxidation (TBARS) measured for fresh eggs (B=0.735 µg MDA/g and BK 0.745 µg MDA/g) and stored eggs (B=0.778 µg MDA/g and BK=0.805 µg MDA/g) were equal for both examined groups (P>0.05). | en |
