Quality of water used in cleaning of bulk raw milk tanks: implementation and evaluation of water chlorination to ensure the product quality

Abstract

Water is the most important and indispensable resource to the maintenance of life in the Earth and it is not different in the farms, once it is a drink for the animals. Its use is also important in activities related to milking. The objective of this work was to evaluate the influence of chlorination of water used in 18 properties located in the Zona da Mata of Minas Gerais, Brazil, on the Somatic Cell Count (SCC) and Total Bacteria Count (TBC) of raw milk. Water samples were collected from hoses used for washing of individual and collective storage tanks of raw milk. In addition, samples of milk were collected for analysis. Chlorination of water did not influence their physicochemical parameters. Chlorinated water samples showed positive results in reducing the Most Probable Number of total and fecal coliforms, however, no significant reduction (p > 0.05) in their number of heterotrophic bacteria was observed. Milk composition was not affected by water chlorination and no significant reduction (p > 0.05) counts of SCC and TBC due to chlorination was found. Therefore, even the water used in cleaning the tanks not presenting good quality, being in disagreement with the Brazilian law, this did not influence the quality of refrigerated raw milk, which has many sources of contamination in the studied region.