LIGNANS IN HOMEMADE AND COMMERCIAL PRODUCTS CONTAINING FLAXSEED

Epidemiologic, in vitro, and in vivo studies support the hypothesis th at mammalian lignans have cancer protective effects. Flaxseed is the r ichest source of plant precursors to mammalian lignans. However, there are limited data on the lignans from processed foods containing flaxs eed, despite increasing flaxseed use. Thus the objective of this study was to quantify the lignans in flaxseed-containing processed foods an d their relationship to the percent flaxseed in the food. Twenty-five foods including raw flaxseed, homemade products containing flaxseed, a nd commercial breads and breakfast cereals with and without flaxseed w ere subjected to an in vitro fermentation designed to simulate the col onic environment necessary for the conversion of plant precursors to m ammalian lignans. The lignan production from cereals containing flaxse ed was significantly greater than that from their component grains (p less than or equal to 0.01), and the lignan production from breads con taining >4% flaxseed was significantly greater than that from breads c ontaining <4% flaxseed (p less than or equal to 0.05). Lignan producti on was significantly related to percent flaxseed in homemade products (r = 0.95, p less than or equal to 0.01) and breakfast cereals (r = 0. 997, p less than or equal to 0.0001). Although a significant relations hip was also observed in commercial breads (r = 0.58, p less than or e qual to 0.05), the correlation was lower because of the variability in different flaxseed varieties and the lignan contribution from other g rains and oilseeds in these products. In conclusion, the addition of f laxseed to processed foods increased the production of mammalian ligna ns significantly. The amount of lignan production was linearly depende nt on the percent flaxseed but was also influenced by other grains and the variety flaxseed.