Effects of Cooking and Defrost Methods on Retinol Concentration of Chicken Liver

This study aimed to analyze the retinol concentration of chicken livers in various brands, batches and types of both organic and free range by HPLC. In addition, the effects of different cooking and defrosting methods on the retinol levels of chicken livers were also determined. Chicken livers samples were roasted for 35 minutes at 200°C, cooked for 40 minutes at (26 to 100)°C, fried for 5 minutes at 180°C. Other samples were frozen for 72 hours and divided to be defrosted by fridge for 8 hours at 3°C, at ambient temperature for 2 hours at 23°C, submersed in water for 35 minutes at 25°C, and microwaved on defrost function for 1 minute, where all methods were compared to its natural state (3°C). The mean retinol concentrations in brands A, B, C and organic and free-ranged were 9152, 4673, 5943, 3401, 30094 µg/100 g (P < 0.001). Significant losses of 39.9 % (P < 0.05), and 26.2 % (P < 0.01) were found when compared to natural state (raw) to roasting and microwave, respectively. This study showed a significant difference between brands and types of chicken livers, and a significant loss of retinol in chicken liver, in food processes commonly used. Otherwise, vitamin A values in chicken liver suggest that consumption could be recommended to prevent vitamin A deficiency.