Physio-chemical and Microbiological Quality Assessment and Detection of Adulterants in Different Sources of Milk in Bangladesh

Abstract

Background: The sources of milk play a significant role on overall milk quality. Therefore, the current study was intended to evaluate the quality (physiochemical, compositional, and microbiological) and detect the adulterants in milk. Methods: A total of 200 milk samples were collected during mid of October to mid of December 2022 from four sources viz. Farmgate (50), Milkman (50), Bazar (50), and Branded packet milk (50). Milk samples were examined for various physiochemical, compositional, microbiological properties, and existence of adulterants. Data were analyzed by one way ANOVA and differences were determined by least significant difference test using RStudio. Results: Physiochemical analysis found significant variation in titratable acidity, protein, fat, salt, Solids-Not-Fat, and Total-Solids content among the sources (p<0.05), while lactose content was found non-significant. The highest (0.17%) and the lowest (0.13%) values for acidity were found in samples obtained from Milkman and Branded packet milk, respectively. Milk sample collected from Farmgate was found significantly higher in protein, fat, lactose, Solids-Not-Fat, and Total-Solids content than the other sources. In microbiological analysis, significant lower Total Viable Count, Total Coliform Count, and Escherichia coli Count were observed in Branded packet milk compared to the milk from Farmgate, Milkman, and Bazar source (p<0.001). In adulteration examinations, only neutralizers (sodium carbonate and bicarbonate) and nitrates were found positive in milk sample collected from Milkman, Farmgate, and Bazar, and their frequency was varied significantly (p<0.001). Overall, the milk obtained from Farmgate was better in terms of nutrient composition and physiochemical properties than the other sources but in respect to microbiological quality, Branded packet milk was found more hygienic. Conclusion: The study found that the variance in milk sources led to changes in the microbial load, physical appearance, and nutritional content of milk. The present study investigated that the addition of different adulterants and variation in time interval (milking to selling) are the main reasons for the deterioration of milk. DOI: 10.18502/jfqhc.11.3.16593

Keywords

• food quality
• food contamination
• milk
• bangladesh