Effect of storage on retinol concentration of Cobb and Ross strain chicken livers.

Liver is an important item in the human diet. The present study examined the retinol concentration in the fresh livers of Cobb and Ross chicken strains, after freezing at -18 degrees C for 90 days. The retinol dosage in the liver was determined by high-performance liquid chromatography. The poultry strain significantly influenced liver retinol levels. The mean retinol value in the fresh samples was 6,678.0+/-1,337.7 and 8,324.1+/-1,158.5 microg/100 g in the Cobb and Ross strains, respectively. These values decreased significantly with liver storage time and reached levels that were 44.1% lower than those of fresh liver after 90 days. The results showed a high concentration of retinol in the chicken livers and demonstrated that more than 30 days of storage causes decreased retinol. Despite the losses resulting from freezing, the ingestion of a typical 100 g portion of liver, regardless of the chicken strain analyzed, exceeds the tolerable upper intake level of vitamin A (3,000 microg/day) for adults.