Nutritional characterization and oxidative stability of α-linolenic acid in bread containing roasted ground flaxseed

- Omega 3 enriched functional bread was developed by adding flaxseed flour.
- In-vitro protein digestibility decreased in 10 (g/100 g) flaxseed bread.
- Optimized bread showed low glycemic index i.e. 51.26.
- In-vitro antioxidant activity of optimized bread was 1489.59 (TE μg/g).
- Calorie content was also increased with increased flaxseed flour.

Flaxseed (Linum usitatissimum) contain three main bioactive components namely α-linolenic acid, dietary fibers and lignan. These are responsible for numerous reports suggesting positive health benefits from flaxseed. Hence different amounts of ground roasted flaxseed flour was incorporated into bread and soluble and insoluble fibers, in-vitro protein digestibility, in-vitro glycemic index (GI), in vitro antioxidant activity and α-linolenic acid (ALA) content were evaluated. Protein digestibility of flaxseed enriched bread was significantly lower than the control (70.9 versus 78.5 g/100 g). In-vitro GI was significantly lower (51.3 compared to 94.6 g/100 g in the control bread) and ALA content of optimized bread (containing 10 g of flaxseed per 100 g), as determined using GC-MS, was about 1.51 g/100 g of bread whereas omega-6 (linoleic acid) content was about 0.15 g/100 g of bread. During 5 days storage period, peroxide value, anisidine value and free fatty acids were increased in flaxseed supplemented bread samples that were stored at 30 °C and at 4 °C.