Phylloquinone (vitamin K1) and dihydrophylloquinone content of fats and oils

Assessment of vitamin K (VK) dietary intakes has been limited by the incompleteness of VK food composition data for the U.S. food supply, particularly for VK-rich oils. The phylloquinone (VK-1) and 2',3'-dihydrophylloquinone (dK) concentrations of margarines and spreads (n = 43), butter (n = 4), shortening (n = 4), vegetable oils (n = 6), and salad dressings (n = 24) were determined by RP-HPLC with fluorescence detection. Each sample represented a composite of units or packages obtained from 12 or 24 outlets, which were geographically representative of the U.S. food supply. Butter, which is derived from animal fat sources, had less VK-1 compared to vegetable oil sources. The VK-1 and dK of the: margarines and spreads increased with fat content and the degree of hydrogenation, respectively. In some margarines or spreads and in all shortenings, the dK concentrations were higher than the corresponding VK-1 concentrations. As the fat content of salad dressings increased, the VK-1 concentrations also increased. Fat-free foods had <1 mug/100 g of either form of the vitamin. No dK was detected in the salad dressings or oils tested. Some margarines, spreads, and salad dressings may be significant sources of vitamin K in the U.S. food supply.