Which of the following is a common method to assess milk quality over time?

A common method to assess milk quality over time is through a shelf life test. This procedure evaluates how long the milk remains safe and palatable for consumption under specific storage conditions. By observing milk for changes in taste, odor, and microbial activity, producers can determine the effectiveness of their handling and storage practices. The results from a shelf life test provide valuable insights into how well a batch of milk will last before it begins to degrade in quality, which is crucial for both manufacturers and consumers in ensuring safety and satisfaction.

In this context, other methods serve different purposes. The freezing test is often used to detect added water or inferior milk quality, but it does not give a clear indication of long-term quality. A pasteurization test checks the effectiveness of the pasteurization process itself rather than the ongoing quality of the milk. The straining test primarily identifies the presence of physical contaminants in the milk but doesn't assess its overall quality over time. Thus, the shelf life test is most relevant for evaluating the continued suitability of milk for consumption.