Q&A for How to Tell if Milk is Bad

Yes. White floating flakes are a sign of spoiled milk. You should toss it immediately.

Sometimes nothing will happen, but you risk contracting food poisoning. This is usually accompanied by symptoms like nausea, vomiting, and diarrhea, and it can be quite severe.

Yes. If it doesn't seem spoiled, it's fine.

The best way to tell for sure is to open the milk, pour some into a class, and observe/smell it. If it smells and looks okay, then it should be fine to drink.

The darker "base" may simply be the chocolate that has settled toward the bottom of the container. Did you shake it up before opening? That said, if you believe it's been left out of the fridge, especially in warm temperatures, you should just toss it.

No. If it smells bad, it is bad, regardless of what the expiration date says.

It depends. Smell it, then try a small taste. If the smell and taste hasn't altered, it is probably fine.

That is the fat content of the milk melting and floating to to the top, because oil is less dense than water (the "base" of milk).

It's very unlikely that it would still be good, but if you really want to try it, open it and see if it smells rancid. You should be able to tell.

It depends. Smell it, then try a small taste. If the smell and taste hasn't altered, you're probably fine.

If it looks, tastes, and smells fine, it's your call. If it's obviously bad, throw it out.

Bacteria such as lactococci and lactobacilli can form, and their by-products produce the odor.

Probably buttermilk and not regular milk. Buttermilk has a definitive smell and a bitter taste. It's also much thicker than regular milk.

Throw it out. There is a good chance you would get very ill from drinking milk a month past its sell by date.

Ice cream. Milk usually has little water content, so it can’t really freeze well.

Check the expiration date first, then drink it. If the milk tastes normal, it's probably fine.

If the whole jug is powdery, don't drink it. If there's some on the lid, it's fine.

When making yogurt (or cheese), people follow specific steps that allow the milk to curdle without producing dangerous bacteria. If your milk curdles on its own, it is likely that it contains some bacteria that are not present in finished yogurt. Throw it out! If you're interested, you can look up directions for making yogurt. It's not that hard to do at home.

Absolutely not. The longest your milk can last past the expiration date is 10 days. Throw it out.

Yes, you should. Bad smells mostly mean bad milk plus sometimes the expiration date isn't always correct if the milk has not been stored properly.

Naturally, if you let milk stay for some time, the part with more fat, which has a thicker consistency, will float at the top and the parts with less fat on the bottom. If this is what happened, it's still safe to drink, and this is even the process used to make cream. However, milk sometimes gets processed in a way that this doesn't happen. This is indicated by some text on the package that the milk was homogenized or has emulgators added. If such milk significantly changes consistency, you shouldn't drink it.

If it looks rotten, throw it out. If it doesn't, use baking soda on a small amount of it. If it bubbles, throw it out.

No. The acid in the milk going bad has caused the proteins to curdle, forming lumps.

No the milk is not bad it is the sound of when you pour cereal that is crispy into the bowl. The liquid puts pressure on the air inside and pushes it around. The air shoves against each pocket's walls until they shatter, making it produce the sound of popping.

Do not drink it. Spoiled milk can make you sick. If your milk tastes sour, throw it away.

No; this is one of the first signs that the milk has turned bad.

The main way to know if milk has spoiled is to smell it. Fresh milk has a clean smell, bad milk will smell off to you. The best way to stop milk going bad is don't open it up very long (i.e. the air causes the bacteria in the milk to grow quickly). Sealed milk (that has been stored correctly) will last longer than daily used milk.

Over time, thick cream will form on the top of the milk (usually occurs with raw milk which hasn't been homogenised). Smell it and it will let you know if it has gone bad. If it smells clean, then shake to mix the fat content with the water content. A good idea is to mix the milk every few days (tip the milk upside down) to keep the fat solids inside the milk.