Here's the trick to knowing if your milk's gone bad

Milk is one of those staple grocery items that always seems to be in the back of the refrigerator. And if you've ever taken a gulp of sour milk, then you probably know it isn't something to ever repeat. No morning should start out that way. Fortunately, there are quite a few signs that can alert you to the fact that the milk has gone bad.

Unfortunately, the expiration isn't a good indicator because it's really an estimate of when a product will reach the end of its "optimal quality" (via Business Insider). If tasting a questionable item is the primary way you like to test if something like milk has turned, then we wish you the best of luck. Bad milk is evident because of the changed texture and consistency. Spoiled milk often curdles making it chunky instead of a smooth liquid.

If the milk tastes unclean or has a sour taste, then it is definitely bad. This happens with the lactic acid in the milk begins to produce bacteria, so go ahead and pour the rest of the milk down the drain.

How to tell if milk is bad without tasting it

There are other cues that should help you realize if milk is bad well before having to taste it. To spare your taste buds, start by looking at the milk, either in the carton or poured into a glass, to examine what might be off.

Spoiled milk can often look discolored. Good milk should be bright white. So, if it has a yellowish tint or even looks like it is a pale white or yellowish, then it is possibly bad (via NDTV Food). It might even look a little brown (via Insider). You'll likely see those lumps and bumps in the milk too if you pour it into a glass too.

Finally, you might want to try smelling the milk if it looks like it might be bad and you don't want to try it. The same unclean, sour taste you would experience if you did take a sip will likely come across if you take a good whiff of the spoiled milk. "If you drank it, you'd probably throw up. It's not food poisoning but it's food objection. The organisms in there produce various kinds of compounds that have an objectional odor. It definitely smells like bad milk," said Theodore Labuza, a food safety expert and professor at the University of Minnesota's Department of Food Science and Nutrition.