The Effect of Germination and Fermentation on the Physicochemical, Nutritional, and Functional Quality Attributes of Samh Seeds

Foods. 2023 Nov 15;12(22):4133. doi: 10.3390/foods12224133.

Abstract

This study investigated the effects of fermentation and germination on the physicochemical, nutritional, functional, and bioactive quality attributes of samh seeds. Regardless of the processing treatment, samh seeds were found to be a rich source of phenolic compounds, namely gallic acid (79.6-96.36 mg/100 g DW), catechol (56.34-77.34 mg/100 g DW), and catechin (49.15-84.93 mg/100 g DW), and they possessed high DPPH antiradical activity (65.27-78.39%). They also contained high protein content (19.29-20.41%), essential amino acids content (39.07-44.16% of total amino acids), and unsaturated fatty acid content (81.95-83.46% of total fatty acids) and a low glycemic index (39.61-41.43). Fermentation and germination increased L*, b*, foaming capacity, oil absorption capacity (OAC), water absorption capacity (WAC), swelling power, microbial counts, antioxidant activity, total flavonoid content (TFC), total phenolic content (TPC), in vitro protein digestibility, protein efficiency ratio, and total essential amino acids and reduced water solubility, emulsion stability, tannin, and phytate contents compared to raw samh seeds (p < 0.05). The highest levels of pH, ash, carbohydrate, fiber, and glycemic index were observed in raw samh seeds, and both germination and fermentation processes reduced these attributes to various degrees (p < 0.05). Germination increased the redness (a*), moisture content, essential and non-essential amino acids, potassium, zinc, phosphorous, stearic acid, and oleic and unsaturated fatty acids and reduced total solids, fat content, iron, zinc, calcium, magnesium, sodium, palmitic acid, and total saturated fatty acids of the samh seeds compared to the raw ones. Fermentation increased the total solid, acidity, fat, protein, calcium, magnesium, sodium, phosphorous, iron, zinc, palmitic acid, and total saturated fatty acids and reduced the a* value, moisture, non-essential amino acids, and total unsaturated fatty acids of the samh seeds compared to the raw ones. In conclusion, samh seeds are a rich source of nutrients that could generally be enhanced by germination and fermentation processes. The reported information facilitates strategies towards the application of these underutilized seeds in foods.

Keywords: bioactive properties; fermentation; functional properties; germination; samh seeds.