Cow's milk should not sit out of the refrigerator for more than two hours.
Here's a breakdown of why and what to consider:
Why Time Matters: Bacteria Growth
When cow's milk is left at room temperature, bacteria that are naturally present multiply rapidly. These bacteria can cause spoilage and, in some cases, can produce toxins that make you sick.
The Two-Hour Rule:
The general recommendation from food safety experts is that perishable foods, including milk, should not be left at room temperature for more than two hours. This is often referred to as the "two-hour rule."
The One-Hour Exception: Hot Weather
If the ambient temperature is 90°F (32°C) or higher, the time milk can safely sit out is reduced to one hour. Warmer temperatures encourage faster bacterial growth.
Potential Risks of Consuming Milk Left Out Too Long:
- Spoilage: The milk may develop an off-putting odor, flavor, or texture.
- Foodborne Illness: Consuming spoiled milk can lead to symptoms such as nausea, vomiting, stomach cramps, and diarrhea.
What to Do If Milk Has Been Left Out:
If you're unsure how long milk has been at room temperature, it's best to err on the side of caution and discard it. "When in doubt, throw it out" is a safe practice.
Summary:
To prevent spoilage and potential foodborne illness, always refrigerate cow's milk promptly. Do not let it sit out for more than two hours, or one hour if the temperature is above 90°F.
