Microbiological and compositional quality of raw milk delivered by small scale dairy farmers to the milk collection centres in Hai District, Tanzania

A total of 310 milk samples were collected from 180 small scale dairy farmers who brought their milk to Milk Collection Centres and 30 vendors in the study area. The bacteriological quality, physicochemical parameters and milk adulteration with Sulphonamides and Tetracycline drug residues were assessed. Microbiological quality evaluation was done based on Total Bacterial Count, Total Coliform Count, E.coli and pathogenic E.coli (O157: H7). For sake of comparisons milk 60 samples from Turiani and Mlandiz were added for antimicrobial residues analysis. In addition, a survey with the use of semi-structured questionnaires was conducted to assess the knowledge of farmers on clean milk production in the study area. Microbiological analyses were carried out using standard cultures, physicochemical properties by use of Automatic Milk Analyser and antibiotic residues using Charm EZ technique. Interviews revealed that 91% of respondents dried cows’ udders after washing, 75% cleaned milk containers with hot water and 86.7% used plastic containers to transport milk. The mean bacterial counts were within acceptable limits as per East African Community standards. About 54% of E.coli was detected, but none for the pathogenic strain. Physicochemical properties of milk were within acceptable ranges for processing. Up to 25% of milk samples from farmers were positive for Tetracycline and Sulphonamides drug residues whilst the vendor samples were negative. More quality tests such as iodine and alcohol tests are recommended to ensure freedom of milk from adulteration with other materials apart from water.