Influence of lactose hydrolysis on galacto-oligosaccharides, lactose, volatile profile and physicochemical parameters of different yogurt varieties

CLAUDIA INÉS VÉNICA; IRMA VERÓNICA WOLF; CARINA VIVIANA BERGAMINI; MARÍA CRISTINA PEROTTI

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE

JOHN WILEY & SONS LTD

Lugar: Londres; Año: 2016 vol. 96 p. 4929 - 4939

0022-5142

BACKGROUND: Different types of reduced-lactose yogurt,obtained by lactose hydrolysis using b-galactosidase enzyme, are commerciallyavailable. The breakdown of lactose modifies the carbohydrate profile,including the production of prebiotic galacto-oligosaccharides (GOS), which couldaffect the survival and activity of starter and probiotic cultures and theparameters of yogurt quality. The extension of these changes is dependent onthe yogurt matrix composition. This study aimed to evaluate the influence of lactose hydrolysis on GOS, lactose, volatile profile and physicochemical parameters of different yogurt varieties during storage. RESULTS: The presence of b-galactosidase enzyme did not affect neither theglobal composition nor the survival of cultures. Overall, the hydrolyzedproducts had lower acidity than traditional ones. GOS were found at similarlevels in fresh hydrolyzed yogurts, whereas in traditional yogurts were notdetected. The proportion of ketones, acids and aldehydes seems to be moredependent on yogurt variety than the addition of the enzyme. Likewise, thestorage period affected the volatile fraction in different degree; the increasein acid compounds was more pronounced in hydrolyzed than traditional yogurts.CONCLUSION: Thiswork shows that it is possible toobtain different varieties of reduced-lactose yogurt, some of them withadditional benefits to health such as reduced-fat, reduced-calories, added withprobiotic/inulin and enriched in GOS, with similar characteristics to traditionalproducts.