Effect of temperature on shelf life, chemical and microbial properties of cream cheese

Abstract

Cream cheese samples were analyzed to find out the effect of recommended storage temperature (4±1°C) and ambient room temperature (21±1°C) on pH, titratable acidity (% lactic acid), moisture content and microbial growth. Percent reduction in moisture content and increase in titratable acidity of cheeses were found to be directly proportional to the increase in storage period. There was a decrease in pH with progress in storage duration. Reduction was significantly higher (P≤0.05) in samples stored at 21±1°C as compared to those refrigerated (4±1°C). Sample 4 showed 41.03% reduction in moisture content and 39.73% increase in titratable acidity whereas, pH value was 3.39 at 21±1°C on 28th day. All these values were significant as compared to the control (P≤0.05). Increase in CFU/g of LAB was more at 21±1°C as compared to 4±1°C. Comparison of data of titratable acidity and CFU log₁₀ of lactic acid bacteria (LAB) shows direct relationship between microbial growth and titratable acidity. Species of Penicillium, Aspergillus, Cladosporium and unknown actinomycetes were isolated from the samples. Distribution and frequency occurrence of fungi were higher at ambient room temperature than at refrigerated temperature.

Key words: Cream cheese, storage period, temperature, titratable acidity, microbial growth.