Changes in microbiological parameters, pH and titratable acidity during the refrigerated and room temperature storage of dahi prepared from the milk of Vechur cows: an indigenous cattle breed of Kerala.

Abstract

Vechur cow is an indigenous cattle breed of Kerala listed as a critical breed by FAO. This research communication is related to the hypothesis that the changes occurring in microbiological quality parameters of Vechur cow milk dahi (VCMD) during storage will be superior to other milk and reflective of the traditional concepts of therapeutic properties attributed to Vechur milk. Microbiological quality of the VCMD stored at room (30 ± 1°C) and refrigerated (4 ± 1°C) temperatures in terms of total viable, coliform, yeast and mold and lactococcal counts is reported in this study, together with titratable acidity and pH. Results are compared with cross-bred cow milk dahi (CCMD) as control. On refrigerated storage, despite the comparable initial microbiological quality, VCMD exhibited significantly lower total viable, lactic acid bacteria, yeast and mold counts than CCMD, from the fifth day onwards for the first two parameters and the tenth day onwards for the last parameter. VCMD exhibited significantly higher pH values than CCMD from the fifth day onwards whereas the titratable acidity was significantly lower from the tenth day onwards. Though this study does not delineate the factors contributing towards the lower microbial population observed in VCMD, it provides an impetus to further researches for scientifically validating its traditionally-reported medicinal properties.