Effect of reconstitution on vitamins A and C content of whey-soy drink mix.

The nutritive quality of a whey-soy drink mix was determined by measuring the retention of added vitamins A and C after the product was reconstituted in boiling water. In one study the mix was mixed in boiling water for up to 5 min and analyzed for vitamin content after each 1 min heating interval. The reconstituted product lost approximately 50% of the original vitamin content after being boiled for 1 min. Little further decrease in vitamin content was observed after several additional minutes of boiling until the 5-min interval when both vitamins dropped to about 35% of original amounts. In another study the mix was reconstituted by mixing the powder in boiling water for 20 s, then allowing the mix to stand at room temperature with no additional heating. This mixture decreased slightly in vitamin content when analyzed at 5 min intervals for up to 25 nin. For maximum vitamin retention whey-soy drink mix should be reconstituted by blending it in boiling water for about .5 min, then allowing the mixture to stand at room temperature before serving.