CHOLESTEROL IN EGGS FROM DIFFERENT SPECIES OF POULTRY DETERMINED BY CAPILLARY GLC

This study compared two methods of egg cholesterol extraction and dete rmination by gas liquid chromatography (GLC), validated by comparison with standard reference material (SRM 1845). The two extraction proced ures were of comparable accuracy with dried whole egg samples of 0.25- 0.5 g, but the direct saponification method was rapid, reduced occupat ional hazard, and quantitative precision was within 2% coefficient of variation. The validated procedure was used to determine cholesterol i n eggs of several domestic avian species. Eggs produced by commercial types of chicken (White Leghorn) had the lowest cholesterol (11.5-11.8 mg/g yolk) compared to 13.0, 14.6, 15.2, 15.6, 16.5, 16.8 and 18.1 mg /g for Rhode Island Red chicken, guinea fowl, New Hampshire chicken, d uck, pea fowl, domestic turkey and wild turkey eggs, respectively. Yol k cholesterol concentration of commercial White Leghorn chicken eggs w as not influenced by age. However, eggs from older birds contained abo ut 23% more cholesterol on a per egg basis (220 versus 179 mg) because of the larger yolk.