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Why Does Yogurt Taste Sharp? Mind Blown!

Why Does Yogurt Taste Sharp? Mind Blown!

One reason why kids often refuse to eat yogurt is because of the sharp or tart taste.

This taste is due to beneficial bacteria in the yogurt. The bacteria create lactic acid, which gives a sharp taste.

The sourness is strongest in plain yogurt because it doesn’t have added sugar, sweeteners, or fruit to tone down the sourness.

Why Does Yogurt Taste Sharp?

Yogurt tastes tart, also called sharp, because of the lactic acid produced by the bacteria strains added to milk in order to make yogurt. Bacteria transform milk sugar, called lactose, into lactic acid. These bacteria strains are not harmful. The tart taste can be reduced by adding sweeteners like honey, agave syrup, or fruit.

Yogurt and Bacteria

How yogurt is made explains why it has such a sharp, tart, or sour taste.

The main ingredient is milk. Milk contains sugars called lactose, which makes milk taste relatively sweet, in comparison to yogurt.

Bacteria are added to heated milk. In recent years, probiotic bacteria have also been added to help aid digestive health.

Different bacterial strains are used, but the main strains are:

  • Streptococcus thermophilus (although it has a similar name, it is not the bacteria that causes strep throat.)
  • Lactobacillus bulgaricus
  • Lactobacillus rhamnosus
  • Lactobacillus casei
  • Lactobacillus acidophilus
  • Bifidobacterium animalis
  • Bifidis regularis
  • Bifidobacterium bifidum

The bacteria cause the milk to thicken, or even firm up and ferment.

Fermentation of anything causes it to have a taste similar to alcohol, which causes it to taste sharp or tart.

Wine, for example, is fermented grape juice.

Grape juice is much sweeter than any wine.

Probiotic Yogurt

Although probiotic bacteria or “live” bacteria added to yogurt has been given a lot of hype in recent years, even regular yogurt without added bacteria still adds some beneficial bacteria to your digestive tract.

However, people who have to take antibiotics or recently suffered from a bad digestive illness that may cause all of the beneficial bacteria in their intestinal tract to die, are often encouraged to take probiotic pills or eat yogurt with added probiotics.

This helps prevent bad diarrhea because your digestive system will not be able to easily digest food without the help of beneficial bacteria.

Unfortunately, a 2017 study showed that some strains of probiotics change the taste of yogurt, making it even sourer or tart.

This is because some strains reproduce faster, causing more fermentation and lactic acid.

The strain that caused the most taste change was Lactobacillus casei.

Fortunately, most probiotic yogurt is made with added sweeteners and fruit, which improve the taste.

Many people cannot taste the difference between probiotic yogurt and regular yogurt.

Signs of Yogurt That Has Gone Bad

Critics of yogurt say that there is no way to tell if yogurt has gone off since it tastes so bad anyway, but all joking aside, there are some easy ways to tell if yogurt has gone bad.

  • A bad smell, or a smell of sour milk.
  • A large pool of liquid on the top.
  • Presence of mold, which is often blue or green.
  • An incredibly bad taste, so that it doesn’t even taste like yogurt or any other recognizable food.

Tasting sharp or tart is not a way to tell if yogurt has gone off, because that’s normal for yogurt, especially plain yogurt.

The older yogurt gets, the more it ferments, causing more lactic acid, which will make the yogurt progressively sharp.

However, if this is a yogurt brand you are used to and it tastes drastically different in any way, including being unbearably tart, then it probably has gone off.

Don’t take the risk. Throw it out.

Yogurt has been known to still be good a week past the sell-by date. Sell-by dates do not mean the date the yogurt has expired.

It just means the date that merchants should no longer try to sell the product. 

According to Women’s Health, the only exception is yogurt that has fruit on the bottom, since mold and yeast grow faster on the fruit than on the yogurt.

Yogurt is Good for You and Good for Mice

Sometimes unexpected discoveries are made in scientific experiments.

You’re studying one thing and finding out information about a completely different area. 

This happened in 2011 to a group at the Massachusetts Institute of Technology studying how yogurt impacted obesity.

They substituted vanilla yogurt for one-third of some lab mice’s diet.

Other mice were fed the equivalent of junk food. A third group, the control group, was fed the usual laboratory mouse chow.

The results, according to researcher Susan Erdman, had “entertaining aspects”.

This is what happened to the yogurt-eating mice.

  • Their fur got brighter and silky soft.
  • Females gave birth to more babies in each litter.
  • Male mice were able to get their mates pregnant quicker and sired more babies.
  • The gonads of the male mice grew five percent heavier than mice on the control diet and 15% larger than males on the junk food diet.

The theory is that probiotics in yogurt help make the mice healthier, which then leads to greater fertility.

So, no matter if that yogurt tastes sharp, eat up, guys. And cut out the junk food.

Frequently Asked Questions About Why Does Yogurt Taste Sharp

Should Yogurt Taste Sour or Has It Gone Bad?

Plain yogurt normally tastes sour because it does not have the sugar or other sweeteners that flavored yogurt has. If the yogurt has a rancid smell, has grown mold, has a large pool of liquid on top, or tastes so bad that you do not want to finish it, then it has gone off and should be thrown away.

How Can I Make My Yogurt Less Tart?

Tone down the tartness or sharpness of yogurt by adding honey, agave syrup, maple syrup, fruit, granola, or a bit of breakfast cereal to the yogurt. You can also mix applesauce into the yogurt. No matter what you use, try just a teaspoon and taste. Add more if necessary.

Can Probiotics Change the Flavor of Yogurt?

A study published in the Journal of Food Science in 2017 showed that some strains of probiotics caused yogurt to become sourer. Those strains had a high growth rate. Probiotics with low growth rates did not change the yogurt’s taste.

The Least You Need to Know

It’s normal for yogurt to taste tart, sharp, or slightly sour.

Plain yogurt and yogurt made with some strains of probiotics will taste tarter than others.

Yogurt gets this taste from the lactic acid produced by bacteria that is needed to turn milk into yogurt.

Signs that yogurt is not safe to eat include mold growth, the appearance of a pool of liquid, a horrible smell, and a vile taste.