Effect of Natural Fermentation on the Chemical and Nutritional Composition of Fermented Soymilk Nono

Abstract

Changes in the chemical and nutritional composition of naturally fermented soy nono were studied at ambient temperature (27 ± 2°C) for 72h. The differently fermented soy nono samples were collected at 6 h intervals and analysed for chemical, proximate and mineral composition using standard laboratory procedures. Biochemical changes in the fermenting soy nono showed a drop in pH from 6.90 to 4.09 while titratable acidity (lactic acid equivalent) increased from 0.42 to 1.82% after 72 h of natural fermentation. The moisture, carbohydrate and fat contents decreased from 93.45 to 92.70, 1.52 to 0.60 and 2.18 to 0.87 % respectively while total solids, ash and protein contents increased from 6.55 to 7.30, 0.23 to 0.74 and 2.62 to 5.09 % respectively. Results reveal that the calcium, iron and magnesium contents in fermenting soymilk increased from 52.86 to 71.43, 28.00 to 40.00 and 7.66 to 8.87 mg/l respectively within time intervals of 0 to 54 h and then decreased to 65.00, 28.00 and 7.83 mg/l respectively till the end of fermentation period while the zinc content increased from 4.42 to 6.75 mg/l throughout the fermentation period. It was evident that there was increase in protein, calcium, magnesium, zinc and iron contents during natural fermentation of soymilk.