Effect of Different Cooking Methods on Folate Content in Chicken Liver

Common liver sources in European countries include cow, chicken, duck, lamb and pig. Despite its decreasing popularity, liver is possibly one of the most nutrient-dense foods, being rich in high-quality protein and low in calories. In animals, the liver is the storage organ for folate. In this study, the effect of different cooking methods on folate vitamers content in chicken liver was investigated. Three folate derivatives, 5-CH(3)-H(4)PteGlu, H(4)PteGlu and 5-HCO-H(4)PteGlu, were identified in the analyzed samples using high performance liquid chromatography (HPLC). The folate content in liver after sous-vide (60 °C/75 min) and steaming (100 °C/30 min) did not differ significantly (p ≤ 0.05) from raw liver folate content (781 µg/100 g). Even liver cooked in a combi oven or grilled (which resulted in significant folate losses) showed much higher folate content, 455–631 µg/100 g and 612–715 µg/100 g, respectively, than the most folate-abundant plant foods. These findings are important as they demonstrate that processed liver has the potential to improve the supply of folate and meet the recommended daily requirements, particularly when folate deficiency is common worldwide.