Shelf-life Study of Pouch Packed UHT Milk- A Qualitative Approach

Abstract

 

The analysis of raw milk subjected to UHT process revealed no seasonal variations in any of the physico-chemical parameter except significant increase in microbial spore count. During storage of UHT pouch milk, significant changes were observed after 45 days for overall acceptability score, pH, protein content, lactose content at 37±1 ºC whereas no microbial spores were found during entire shelf-life study. Based on results, it seems that the Maillard browning could be responsible for bringing pronounced changes in physico-chemical parameters as well as decreasing the degree of overall acceptability of UHT milk. The initially cooked/burnt flavour noticed by panellist was overruled by other off-flavours like chalky, stale, etc. after 45 days. However, the UHT milk was acceptable till the end of storage period.