There are many adults, even cooks, who don’t know the difference between sour cream and yogurt. As such, we are here to clarify this common misconception.
There are quite a few dairy products that are white and sour, as such, it is not so strange that there is oftentimes quite a lot of confusion. And if we are completely honest, sour cream and yogurt can be hard to differentiate from a distance. However, taking a closer look, they do differ in texture, smell, taste, and, most importantly, in their behavior when used in cooking.

What is Sour Cream?
Sour cream is a fermented dairy cream. By introducing a specific type of bacterial culture to the dairy cream, the fermentation process is initiated. During the process, bacteria produce acid, flavor, and add thickness. The process is stopped by re-pasteurizing the cream and essentially killing the bacteria.
Bacteria used to turn cream into sour cream: Streptococcus cremoris, Leuconostoc dextranicum, Streptococcus lactis, Leuconostoc citrovorum, and Streptococcus diacetilactis.

What is Yogurt?
The yogurt-making process is very similar to the one described above; however, the initial ingredient is not dairy cream but milk, and different type of bacteria are used. In addition, the types of bacteria used to make yogurt don’t require re-pasteurization.
Bacteria used to turn milk into yogurt: Lactobacillus lactis, Lactobacillus bugaricus, Streptococcus thermophilus, and Lactobacillus helveticus.
The Main Difference Between Sour Cream and Yogurt
Yogurt is very high in nutritional value compared to sour cream. It also contains way less fat and is as such a healthier choice. On average, there is about 10% of fat in yogurt and twice as much in sour cream.
Cold Dishes
As yogurt and sour cream are rather similar, they are interchangeable when applied in cold dishes or used as a garnish. Though, you should keep in mind that yogurt is normally tangier than sour cream.
Cooking
When the thermal process takes place, things are not that simple and yogurt and sour cream can’t be interchanged as freely as with cold dishes. Greek yogurt is still a good substitution, as long as you pay extra attention when simmering it.
Other Sour Cream Substitutions
Aside from Greek Yogurt, you can use buttermilk or soymilk and thicken them with softened butter to replace sour cream. Cottage cheese and cream cheese are other alternatives. Another interesting option is unsweetened evaporated milk with vinegar or lemon juice. There are also vegan sour cream alternatives available or can be made at home from scratch.