What temperature should water not rise above when thawing food under running water?

When thawing food under running water, it is recommended that the water temperature does not rise above 41°F. This guideline is critical for food safety because maintaining this temperature helps to prevent the growth of harmful bacteria that can occur when food is in the 'danger zone'—typically between 41°F and 135°F.

Thawing food in running water at temperatures above 41°F increases the risk of certain pathogenic microorganisms thriving on the surface of the food, potentially leading to foodborne illnesses. It is crucial to keep the food at a safe temperature throughout the thawing process to ensure that it remains safe to consume.

The other temperature options provided (45°F, 35°F, and 32°F) are either above the recommended safe level or below the freezing point, which would not effectively thaw the food. Thus, 41°F is the established standard to minimize risks while allowing adequate thawing time.