Effects of Single and Double Treatment Methods on the Micronutrients in Mucuna pruriens (Velvet Bean) Seed Flour

Abstract

Mucuna pruriens seed is an underutilized legume with good nutritional value with a possibility of changes in its micronutrients’ composition during processing whose data is scanty. Mucuna pruriens seed flour was therefore evaluated for the effect of soaking, cooking, roasting, germination and fermentation as well as some double treatments on its vitamin and mineral contents. Mucuna pruriens seeds were cleaned, washed, soaked, cooked, roasted, germinated and fermented. Vitamins and minerals composition were determined. Soaking, cooking and roasting significantly reduced (p<0.05) all the vitamins. Vitamin B9 was significantly (p<0.05) reduced the most with a range of 0.28 – 21.88 mg/100g. Vitamins B1, B2, B3 and B12 were significantly increased by fermentation with vitamin B2 increased the most (0.26 to 1.50 mg/100g; represents 577% increase). Vitamin B9 was the most significantly reduced (p<0.05) from 21.88 to 0.28 mg/100g by 72 h fermentation. Cooking reduced all the minerals except potassium and sodium. Potassium was increased from 690.50 to 930.75, 760.50 and 730.00 mg/100 in 10, 15 and 20 minutes roasted samples respectively. Germination significantly (p<0.05) reduced all the minerals except 24 h germination which increased calcium from 218.17 mg/100g in the raw Mucuna pruriens seed to 234.36 mg/100g. Fermentation generally reduced all the minerals significantly (p<0.05) except calcium and zinc. Germination and fermentation have proved to be suitable methods for the enhancement of vitamin B2, B3, B12 and zinc in Mucuna pruriens seed flour. Combined process treatments reduce most vitamins and minerals in M. pruriens seed flour and are therefore not suitable for their improvement.