How much milk should be flushed from a tank sampling petcock before taking an official bacterial sample?

Flushing the sampling petcock before taking an official bacterial sample is crucial to ensure that the sample accurately represents the milk within the tank rather than being contaminated by residual milk that may have remained in the lines or the sampling device. The recommended practice is to flush a quantity sufficient to purge any old milk or contaminants. In this case, flushing 2 quarts is the standard procedure, as it effectively helps to clear the system and ensures that the bacterial sample taken reflects the current condition of the milk in the tank. This amount is generally seen as an adequate volume to guarantee a clean sampling process while minimizing waste. Adhering to this guideline helps maintain the integrity of the testing results, which is essential for dairy operations to monitor quality and safety.