Enhancing the sweetening power of lactose by enzymatic modification in the reformulation of dairy products

Lactose solutions of up to 50% (w/v) were incubated with lactases and glucose isomerases for subsequent implementation in dairy product samples to enhance sweetness. A degree of hydrolysis of >90% and of isomerisation of 50% were attainable. The sensory sweetening power of lactose in solutions of up to 50% (w/v) can be enhanced 2-3 times. Based on sensory experiments, application of this bi-enzymatic system in yoghurt and pudding samples allowed for a 10-20% (w/w) reduction in the total sugar content, whilst retaining equal sweetness. The growth of yoghurt starter cultures was not affected, yet furosine formation more than doubled in high heated, enzyme-modified milk.