Comparative Effects of Sprouting and Fermentation on the Nutrient and Anti-nutrient Composition of Soybeans (Glycine max)

Abstract

Sprouting and fermentation are traditional methods used to make legumes more nutritious by increasing nutrient availability and reducing antinutrients. In this study, we looked at how sprouting (for 24, 48, 72, and 96 hours) and spontaneous solid-state fermentation (for 24 to 72 hours) affected the basic composition, mineral and vitamin content, and antinutritional factors of soybeans (Glycine max) from Bida New Market. Unsprouted and unfermented soybeans served as controls. Sprouting gradually raised moisture (5.47–5.73%), fat (3.13–4.22%), and protein (37.41–39.09%), while carbohydrate (61.31–53.93%) and fiber (5.15–5.34%) decreased compared to the control. Antinutrients also dropped as sprouting time increased: tannins (151.91 to 137.19 mg), phytates (21.76 to 17.12 mg), and oxalates (6.37 to 3.90 mg). Fermentation increased protein (35.13±0.01%) and ash (3.43±0.04%) but lowered carbohydrate (33.64±0.09%), fat (15.36±0.2%), fiber (9.46±0.04%), and moisture (2.98±0.01%). Minerals like calcium (18.56±0.00 mg), potassium (28.01±0.01 mg), sodium (9.02±0.01 mg), iron (8.98±0.01 mg), zinc (16.30±0.01 mg), and magnesium (23.62±0.01 mg) all increased. Vitamins such as thiamine (1.88±0.22 mg), riboflavin (1.75±0.07 mg), and niacin (2.72±0.01 mg) were also higher. These results show that both sprouting and fermentation can improve the nutritional value of soybeans and reduce antinutrients. Fermentation in particular boosts mineral and vitamin content, making soybeans a better plant-based protein. These findings suggest that these traditional methods are sustainable and affordable ways to improve legume nutrition and support food security, especially where soybeans are a main protein source.