Effect of heat treatments on antioxidant properties and insulin content of camel milk

Abstract

The aim of this study was to evaluate the changes in antioxidant activity and insulin content of camel milk after thermal treatment. Camel milk samples were collected from dairy farm (ICAR-National Research Centre on Camel, Bikaner, India). The samples were processed with two heat treatment methods: High Temperature Short Time (HTST) and Low Temperature and Long Time (LTLT) and fresh camel milk (untreated) was used as control. The antioxidant activity of the milk was measured by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and 2, 2?-azino-bis (3-ethylbenzthiazoline-6-sulfonate) (ABTS) radical scavenging activity. Insulin concentration was determined using ELISA kits in the different milk samples. DPPH radical scavenging activity was significantly lower (p<0.05) in LTLT heat treated (pasteurised) milk compared to fresh milk (Control). However, no significant difference was found between HTST group and control. Similar results were observed for ABTS radical scavenging activity of the milk samples. There was also no significant (p>0.05) difference in the insulin content in heat treated groups when compared with control group. Thus, data suggested that the milk processing by HTST pasteurisation preserves the antioxidant activity as well as insulin content in camel milk.