If the fat content of milk increases by 10% or more, by how much must the pasteurizer temperature be increased?

The correct increase in pasteurizer temperature when the fat content of milk increases by 10% or more is 5 degrees Fahrenheit. This requirement is based on the relationship between fat content and the thermal processing necessary for effective pasteurization.

Higher fat content in milk creates a greater viscosity, which can shield pathogens from the effects of heat. Therefore, to ensure that all harmful microorganisms are effectively killed during the pasteurization process, an increase in temperature compensates for the protective effect of the fat. The established practice is to adjust the temperature upward by 5 degrees Fahrenheit for a significant increase in fat content to maintain the safety and quality of the product.

Other options reflect either a lesser or greater adjustment, which does not align with the standard practices established in food safety protocols. Maintaining correct temperature control is crucial for ensuring that milk products are safe for consumption while retaining their intended quality.