Effect of heat treatments on sensory characteristics and shelf-life of skimmed milk

Abstract

The present study was conducted to observe the effect of various heat treatments on sensory characteristics and shelf-life of skimmed milk at the Department of Animal Products Technology, Faculty of Animal Husbandry and Veterinary Sciences, Sindh Agriculture University Tandojam, during year 2012-2013. The skimmed milk was produced from buffalo milk through cream separator and then divided into four groups viz. A, B, C and D. The group A was kept as untreated (control) and B, C, D (treated at 60°C for few s (thermization), 65°C for 30 min (pasteurization), 110°C for 10 min (sterilization), respectively. The parameters studied included; sensory attributes such as appearance/color, taste/flavor and body/texture scores and shelf-life at cold storage (6±2°C) and at room temperature. Appearance/color of pasteurized and sterilized skimmed milk was not acceptable compared to thermizide and control skimmed milk. Sterilization process improved the taste/flavor and body/texture of skimmed milk. Shelf-life of skimmed milk was remarkably (P<0.05) better with sterilization process at room temperature as well as at cold storage (6±2°C).    Key words: Heat treatment, sensory characteristics, skimmed milk.