EFFECTS OF SODIUM BICARBONATE BLANCH ON THE RETENTION OF MICRONUTRIENTS IN SOY BEVERAGE

Soy beverage was prepared with a tap water or 0.25% sodium bicarbonate blanch. Retentions of vitamins B₁, B₆, niacin, pantothenic acid, folacin and the amino acids lysine, methionine and tryptophan were determined from samples taken after various process steps. The results indicate that bicarbonate blanch reduces the retention of most of the B vitamins but slightly increases the retention of tryptophan in the soy beverage. More than 50% of niacin, pantothenic acid and vitamin B₆ was lost in the blanch water, irrespective of treatment. Reuse of blanch water in latter stages of the soy beverage process could result in 95% or more recovery of all measured nutrients, with the exception of thiamine.