The Changes in Goat Milk during Heating and Storage after Milking

Abstract

In this study, it was aimed to investigate the changes in goat milk after heating at different temperatures and during storage in different packaging materials. For this purpose, milks obtained from a farm producing goat milk in Bolu in Turkey were divided into two groups, the first group was pasteurized at 65°C for 30 min and the second group at 95°C for 5 min. Each group of pasteurized milk samples was again divided into two groups and filled into transparent and brown bottles. Samples were taken before and after heat treatments to reveal the effect of heating, and also on 0 th , 5 th and 10 th days of storage period (at +4°C) to determine storage effect. The results showed that heat treatment caused increases in dry matter values of goat milk samples (P<0.05). On the contrast, heat treatment had no effect on the values of fat, acidity, viscosity and vitamins significantly (P>0.05). Heating the milk samples by High Pasteurization method resulted with significantly high values of sedimentation. Besides hydroxymethylfurfural, nonenzymatic browning compounds and L* values increased as the heating value increased. The acidity values of the samples increased during storage (P<0.05). The hydroxymethylfurfural and nonenzymatic browning compounds values of the Low Pasteurized and High Pasteurized milk samples were differed from each other (P<0.05) while the packaging materials and the storage time were had no significant effect (P>0.05). Also, sedimentation and L* values were affected during storage (P<0.05).