The dairy industry loses millions of dollars every year from product deterioration caused by spoilage bacteria. Spoilage bacteria result in shorter shelf life and decreased quality for milk products. By identifying the specific types and numbers of microbes involved, we can improve shelf life and quality by reducing bacterial contamination.
Negative results for both tests (HR-1 and HR-2) indicate effective sanitation practices on the pasteurized side and the potential for excellent keeping quality. However, if actual keeping quality (45°F for 14 days) is not consistent with the negative test results, spoilage is likely related to the presence of heat-resistant, spore-forming bacteria.