Assessment of the Situation of Fresh Milk Hygiene in Milk Collection Points in the North of Vietnam in Terms of Microbiological Criteria and Antibiotic Residues
Abstract
Analyses were made for 86 fresh milk samples taken from different milk collection points in theNorth of Vietnam (Ha Noi, Thanh Hoa and Vinh Phuc). The results indicated that the contamination level
of milk samples was higher than the hygience standard and this level was diffirent among the studied
provinces. In detail, the rate of satistified samples in total bacteria criteria varied from 64,52% to
71,43%; Coliforms from 70,96% to 76,47% and E. coli from 83,87% to 85,71%; As regard to Salmonella
and Staphylococcus criteria, the rate was from 93,55% to 95,24% and from 76,47% to 80,95%,
respectively. The study also showed that the bacteria which were isolated from the milk had a high
level of toxicity. They could kill 100% laboratory animals (mouse) within 24 to 72 hours (there were 4/6
strains of E. coli ; 2/3 strains of Salmonella and 5/6 strains of Staphylococcus aureus). In terms of
antibiotic residues, the incidence of samples which sastisfied the hygienic standard was the highest in
Thanh Hoa province (88.24%), followed by Vinh Phuc province (80.95%), and the last was Ha Noi city
(77.42%). The results should warn consumers of the quality of fresh milk available in the local market.