Standardization of different levels of lactose hydrolysis in the preparation of lactose hydrolyzed yoghurt

Abstract

Yoghurt is a unique fermented dairy product, consumed throughout the world and the trend ofconsumption is increasing due to its unique health benefits. Yoghurt mix is often supplemented with MSNF(milk solids-non-fat), it may contain as much as 5.7% unhydrolysed lactose. Lactose can be hydrolysed withan enzyme lactase. Deficiency of lactase in lactose-intolerant persons leads to gastrointestinal disorders; suchconsumers may find it difficult to consume lactose unhydrolysed yoghurt. The production of lactosehydrolysed yoghurt by pre-hydrolysing of lactose in the yoghurt mix by enzymatic hydrolysis of lactose wasstudied using standard materials and methods. Among the different levels of enzyme examined (0.12 to0.56% of yoghurt mix with increment of 0.04% at each level), 0.16, 0.32 and 0.52% were found suitable tohydrolyse 50, 70 and 90% lactose in the yoghurt mix, respectively. Lactose hydrolysed yoghurt (LHY)prepared from 70% followed by 50% lactose hydrolysed mix (LHM) had significantly higher scores for bodyand texture, flavour and overall acceptability than control (P