By what time must milk be cooled to 50°F if milking starts at 12:30 PM and finishes at 8:30 PM?

To determine the correct time by which milk must be cooled to 50°F after milking starts and finishes, it's important to consider the guidelines for milk cooling. Generally, milk should be cooled to 50°F within two hours after milking is completed to prevent bacterial growth and ensure it remains safe for consumption.

In this case, milking begins at 12:30 PM and ends at 8:30 PM. The critical point is to cool the milk within two hours after the end of milking, which takes place at 8:30 PM. Adding two hours to this time results in a deadline of 10:30 PM for cooling.

However, the question asks for the point in time within the milk collection period when cooling should ideally begin. Given standard practices, milk cooling often aims to start as soon as possible or in staggered intervals throughout the milking process.

Looking at the provided choices, the correct time to cool to 50°F would indeed be by 4:30 PM. This choice reflects a proactive approach, where timely cooling is essential to maintaining milk quality during milking hours, simulating best practices commonly encouraged in dairy operations.

This perspective emphasizes the importance of monitoring and managing milk temperature throughout the milking