Effects of germination on tocopherol, secoisolarlciresinol diglucoside, cyanogenic glycosides and antioxidant activities in flaxseed (Linum usitatissimum L.)

The changes in chemical composition and antioxidant activities of brown and golden flaxseeds (Linum usitatissimum L.) during 5‐day germination were investigated. Flaxseeds germinated in a dark and closed incubator at the temperature of 25 °C. With noticeable reduction in fat content, germinated flaxseeds were determined higher percentage of linolenic acid. The total phenolic content and antioxidant activities increased with germination time. The highest amount of secoisolarlciresinol diglucoside (SDG) was found in 2‐day germinated brown and golden flaxseeds, which increased 1.04‐fold and 1.09‐fold, respectively, and germinated flaxseed oil was found rich in SDG. Intriguingly, germination increased the α‐tocopherol content from 0 to 4.58 mg per 100 g and 0 to 7.83 mg per 100 g in brown and golden flaxseeds while γ‐tocopherol decreased. Germination process also reduced the total content of cyanogenic glucosides, the content of linustatin, neolinustatin and lotaustralin decreased significantly, but caused an increase in the content of linamarin. Therefore, germination can be utilised as an effective method to improve the nutritional value of flaxseed.