Effects of germination on chemical composition and antioxidant activity of flaxseed (Linum usitatissimum L) oil

Abstract

The present study was carried out to determine the changes in proximate composition and physicochemical characteristics of flaxseed during germination. Flaxseed was germinated for 4 days and observations were taken every day throughout the study. Changes in the seed reserve and antioxidant activity were determined during germination. The oil content of the cultivar decreased from 35.10 to 27.22%. During the germination period, the total protein content increased to 23.84%. Germinated flaxseed showed significantly higher unsaturated as compared to saturated fatty acid ratios and higher calculated oxidizability (Cox) values. The Saponification value ranged from 182 to 192 mg KOH·g-1 oil during germination. The highest peroxide value (2.4 mequiv O2·kg-1 oil) was observed at the end of germination. The unsaponifiable contents ranged from 1.62 to 1.18%. The oxidation value of the oil samples were statistically in the same range (4.1-6.4%). After 4 days of germination, oil stability was reduced to 1.0 h. The increase in ascorbic acid content was steady. Total phenolic acid contents differed significantly. The greatest concentration was detected in non germinated flaxseed oil. Germinated Flaxssed oil showed an important free radical scavenging activity towards 1-1-diphenyl-2-picrylhydrazyl (DPPH) free radicals.