Q: What is that liquid on top of yogurt and what should be done with it?
A: Finding liquid on top of yogurt is commonplace for most yogurt eaters. That yellowish or cloudy white liquid is annoying and can be disgusting to some. Many people pour the liquid off the top while others stir it back into the yogurt.
The liquid is called whey and it is one of two primary proteins found in milk. The other protein is casein. Yogurt is created by adding a bacteria (good bacteria called Streptococcus thermophilius and Luctobacillus bulgaricus) to heated milk. This causes it to ferment.
During the fermentation process, the casein protein makes the thick portion of yogurt, while the whey remains a liquid. The whey is strained out during the manufacturing process but not all is removed. The more straining of the whey, the thicker the yogurt becomes.
The whey separates and moves to top of the yogurt as it sits in the refrigerator or is disturbed. The thicker portion remains on the bottom. Essentially, why is the one to blame for that unsightly pool atop the creamy whiteness of your yogurt.
The liquid (whey) on top or in yogurt is harmless. It is normal and commonly visible in many dairy products like sour cream and cottage cheese. It contains nutrients like calcium, potassium, and protein so it is best to stir it back into the yogurt. It can also be strained into a container and used in smoothies or recipes for additional nutrients. If you don’t care for the liquid or want a thicker yogurt, simply discard it into the sink and enjoy.