Enzyme technologies for alleviating lactose maldigestion / Tecnologías enzimáticas para aliviar la mala digestion de la lactosa

Lactose reduction in milk by β-galactosidase prior to consumption is one of the current modali ties of alleviating lactose maldigestion. However, hydrolysis of lactose results in flavour changes in milk: glucose and galactose are between three and four times sweeter than lactose, and many lactose maldigesters do not like the taste of lactose-hydrolysed milk. The addition of exogenous β-galactosidase to meals has been shown to alleviate lactose maldigestion adequately, and so β-galactosidase could be added to milk if the lactose could be protected from the hydrolytic action of the added enzyme. Liposomes, which have recently shown potential as carriers of enzymes, could be good vehicles for the addition of β-galactosidase to milk. β-galactosidase can be successfully encapsulated in liposomes which have been shown to be very stable when suspended in milk stored at refrigeration temperature. Lactose hydrolysis is minimal when liposomal β-galactosidase is added to milk. In vitro digestibility studies have shown that the liposomal β-galactosidase is available for digesting lactose in milk. Stable blends of β-galactosidase and dry milk powders have also been used. Results have shown that up to 95% of the original activity of the fungal lactase was retained in blends of the enzyme and milk powder when stored under nitrogen at 45 °C for 6 months.