Milk can safely sit out at room temperature for up to two hours. If the temperature is above 90°F (32°C), it should be discarded after one hour to avoid bacterial growth that can cause spoilage and foodborne illness. It's best to refrigerate milk promptly after use and check for any signs of spoilage such as changes in smell, taste, or appearance. Leaving milk out too long, even intermittently, can reduce its overall shelf life and lead to off flavors due to oxidation. Ultra-pasteurized milk may be less sensitive but still should be kept cold for best quality. In summary:
- Up to 2 hours at normal room temperature
- 1 hour if above 90°F (32°C)
- Refrigerate immediately after use
- Spoiled milk can smell, taste, or look different
These guidelines are recommended by food safety authorities and dairy experts to ensure milk stays safe and fresh.
