Milk is a highly perishable item. Improper storage conditions and high room temperature can make it go bad within a few hours.
But it often happens that we leave milk out on the kitchen counter unintentionally. Does this mean we should discard it?
Is it safe to drink milk left out overnight? The US Food and Administration suggests discarding milk that has been left out of the fridge for longer than 2 hours. However, a lot depends on the room temperature. If it has been only a little over 2 hours and the room temperature is low, you may find that the milk is still good to drink.
In this article, you will learn everything about proper storage conditions of milk, its shelf life, and signs of spoilage, as well as about the risks of drinking milk that has been left out of the fridge for longer than two hours.
What Is The Best Way To Store Milk?
The best way to store milk is obviously in the fridge. Here are a few simple rules for storing milk.
- Put the milk in the fridge as soon as you get home. It is important to keep milk refrigerated at all times. And here’s a tip. Make milk the last item you add to your cart while shopping at a grocery store. This way you will avoid having the milk at room temperature unnecessarily.
- Don’t store the milk on the fridge door. This is the place most people store the milk when they bring it home as the bottles and cartons milk usually comes in fit perfectly on the fridge door shelves.
But this is not the best place to store milk as the fridge door shelves are the warmest spot in the fridge.
Whenever you open the fridge door, you cause the products stored on it to undergo temperature changes as you are essentially dragging them into the warm temperature of the room.
Pick the coolest spot of the fridge to store the milk. It is the back of the fridge on one of the middle shelves.
- Keep the container with milk tightly sealed. If the seal on the milk bottle or carton is broken and doesn’t close tightly, consider transferring the milk into another container.
- Always store opened milk in the fridge. No matter what type of milk you are using, you should always keep it in the fridge once you have opened it. Some milks, such as canned milk and UHT milk can be stored at room temperature before they are opened. But don’t be tempted to leave them out after you have opened them.
How Long Does Milk Last?
Milk is a highly perishable food item. The shelf life of all types of milk is indicated on the packaging.
The general rule is that unopened milk lasts around 7 days past the printed date if the seal is intact and the milk has been properly refrigerated.
Once opened, you should use the milk within 5-7 days. Even long-life milk that has a shelf life of multiple months when unopened should be used within a week after you have opened it.
If you want to extend the shelf life of opened milk, freeze it. Milk stored in the freezer keeps well for up to 4 weeks.
Left Milk Out Overnight – Has It Gone Bad?
Leaving milk out overnight or for multiple hours is something that can happen to everyone who uses milk often.
You may pour it over your morning cereal and go about your day without remembering to put the gallon back into the fridge.
Or, you may be lazy to put away the groceries forgetting that there is a bottle of milk somewhere in your shopping bag.
So, what should you do with milk that has been left out at room temperature for many hours? Should you store it in the fridge and use it like regular or should you discard it?
The general rule for perishable foods is that you shouldn’t leave them out for longer than two hours. But not all foods go bad after the 2-hour mark. Does milk go bad if you leave it out overnight?
The answer to this question depends on a few things. Firstly, how warm is it in the room where the milk was left?
The warmer it is in the room the quicker will the bacteria grow in the milk and cause it to spoil. If this is the case, it’d be good to discard the milk.
Secondly, the type of milk matters too. Unopened ultra-pasteurized milk can be safely be left at room temperature.
You know you can leave the unopened milk at room temperature if you have bought it from the unrefrigerated section at the store.
And lastly, milk that has just been boiled can be safely left out of the fridge for around 8 hours. If for some reason you can’t store the milk in the fridge, keep boiling it every 6-8 hours.
But know that it will thicken after a few boiling sessions. In this case, you can add water to the milk to maintain its consistency.
What Are The Risks Of Drinking Milk Left Out Overnight?
Drinking milk that has been left out overnight is not recommended. Contaminated milk may cause such health issues as upset stomach, cramps, fever, etc.
Luckily, bad milk generally undergoes noticeable flavor and smell changes.
So, even if you try to drink the milk that has been left out overnight without knowing it, you will surely understand that something is wrong with it and will stop drinking it.
But what if you have left the milk out of the fridge for only a few hours? Can you still drink it?
While it is always good to err on the safe side and discard it, you may give it a try after sniffing it and inspecting the consistency.
If you do decide to do this, consider if the milk left out overnight is traditional milk or pasteurized milk.
The pasteurization process implies heating milk to specific high temperatures. This kills most of the pathogens found in raw milk, minimizing its chances of it going bad.
But even pasteurized milk is susceptible to bacterial contamination when the seal is broken or opened and the milk is left out at room temperature.
Additionally, as the pasteurization process kills most of the bacteria in the milk, it may not have a distinct sour smell when gone bad.
So, the only way to know if you can still use the milk is to drink it.
And while the US Food and Drug Administration recommends discarding milk that has been left out for longer than 2 hours, many people find that in most cases the milk is still fine to drink.
Traditional milk, on the other hand, has a shorter shelf life and goes bad faster. So, it’s best to discard it if you have left it unrefrigerated for a few hours even without opening the seal.
How Does Milk Go Bad?
Milk goes bad due to the overgrowth of bacteria. When you leave milk at a temperature above 40°F, a suitable environment is created for the growth of bacteria.
This compromises the flavor and texture qualities of the milk. The overgrowth of these bacteria is also what makes spoiled milk smell bad.
Additionally, when you open a bottle or carton of milk, the milk is also exposed to various bacteria from the environment. This is why it is important to store milk properly especially once you have opened it.
How Do You Know Milk Has Gone Bad?
Spoiled milk is very easy to spot. It is important to know what are the signs of spoilage of milk as even the ‘Use by’ date on the milk packaging doesn’t mean it’s good and safe for consumption.
Here’s how you know the milk has gone bad:
- Off-putting smell. The first sign to give away bad milk is the unpleasant smell. Good milk has very little distinct odor. Bad milk, on the odor hand, has an unpleasant sour odor.
- Color changes. Another visual sign of bad milk is the changes in color. Spoiled milk has a dingy yellow color. Milk is naturally white. So, if you notice any yellowness, discard the milk.
- Texture changes. Depending on how bad the milk is, its texture may be lumpy and slimy. Milk that has just started to go bad may not have any texture changes. If you notice other signs of spoilage, such as changes in smell or color, don’t drink it just because the consistency looks good.
- Flavor changes. If the milk looks and smells good but you want to be sure that it hasn’t gone bad, give it a try. Take a sip. If you experience an acidic flavor instead of the mild sweetness of milk, then it’s time to discard it.