Bacteria Counts in Raw Milk

There is little doubt that raw milk is the most scrutinized agricultural commodity. Appendix N of the Pasteurized Milk Ordinance requires that all bulk tank milk be tested for beta-lactam antibiotics. This document also sets the regulatory levels for somatic cell counts (SCC) and bacteria levels in raw bulk tank milk. Milk processors are required to perform the regulatory testing. Many progressive milk processors provide premiums for high quality milk (low SCC and bacteria counts). From the time milk is harvested from a cow’s udder, milk quality cannot improve. While SCC will not change after harvest, there are numerous reasons bacterial levels can be increased. Ideally, bacteria levels within the udder are low and additional bacterial contamination is minimized. When bacteria counts are elevated above acceptable levels, both quantitative and qualitative analyses can help pinpoint the causes.