Hydrolysis of UHT milk lactose by partially purified crude enzyme of β-galactosidase obtained from Lactobacillus plantarum B123 indigenous strain

The β-galactosidase activity contained in the enzyme at 4.8 and 7.2 U/mL milk were applied for the hydrolysis in two types of UHT milks, full cream and low fat milks, with their respective total fats 3.5 and 1.0 persen w/v.

The highest degree of lactose hydrolysis in full cream milk was 60.0 persen of its initial lactose concentration, achieved by the application of 7.2 U β-galactosidase/mL milk for 9 hat 50°C. The hydrolysis in low fat milk could be at 81.1 persen under the same condition. Enzyme activity, hydrolysis time and total fat concentration in milk affected the lactose hydrolysis (P ≤ 0.05). The β-galactosidase contained in the partially purified enzyme has a potential use for commercial production of low lactose milk. </p> <p>International Food Research Journal 22(6): 2274-2279 (2015) </p>