Inhibition of Galactooligosaccharide (GOS) Degradation in High-Heat-Treated Goat’s Milk as a Raw Material for Functional Dairy Products

The aim of this study was to analyze the inhibition of galactooligosaccharide (GOS) degradation in heat-treated milk with permeate obtained by microfiltration and concentrated by ultrafiltration. An attempt was made to obtain raw material with a designed composition and stability in terms of GOS content for the production of fermented milk beverages. This study is important due to the versatile possibility of using milk and permeate with GOS in further processing and food production. During the heat treatment of goat’s milk, GOS degradation was approx. 16%. However, no changes in GOS content were observed in goat’s milk with permeate after 30 and 60 min of heating between 72 and 92 °C. Therefore, goat’s milk with permeate in terms of GOS content was stable for up to 60 min, regardless of the temperature. The addition of permeate effectively inhibits GOS degradation in milk. It has been shown that the produced raw material with a stable GOS content during heating can be further used for the production of kefir.