Lipolytic activity of milk with different somatic cells levels

M.V. Santos C.A.F. Oliveira L.F.B. Augusto A.A. Aquino About the authors

The lipolytic activity of milk with different somatic cell counts (SCC) was investigated in samples with low (100,000 and high (1,000,000 cells.ml¹) SCC in order to obtain the following treatments: A) low SCC milk; B) high SCC milk; C) low SCC milk with somatic cells added, taken from high SCC milk. All samples were pasteurized and kept refrigerated at 6ºC for 21 days. Repeated measures during storage time were performed from pasteurized milk at days 1, 7, 14 and 21 to evaluate free fatty acid (FFA) concentrations. No effect of treatments was observed on milk FFA concentration during storage period, nor during each day of sampling, with FFA averaging 0.181; 0.159 and 0.153meq/kg for treatments A, B and C, respectively. FFA concentration in pasteurized milk increased during the storage period, independently of the milk SCC, as the level of FFA was 0.121 meq/kg on day 1 and 0.219 on day 21. Addition of somatic cells to low somatic cell milk did not increase lipolysis rate of milk during refrigerated storage. It can be concluded that pasteurized milk fat breakdown during refrigerated storage is not related to enzymes from somatic cells.

milk; somatic cell enzymatic activity; lipase

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