What does soaking meat in buttermilk do?

Online Answer
Buttermilk is a secret weapon of many restaurant chefs. They pre-soak chicken, fish and other meats overnight before cooking to give it a hint of tanginess. The good bacteria in buttermilk also speed up the breakdown process.
Related Questions 📌
Buttermilk is a good source of calcium and phosphorus, as well as vitamin D if it has been fortified. Full-fat varieties are also rich in vitamin K2 ( 5 , 6 ).
Pour buttermilk (1/4 cup for a quart jar or 1/2 cup for a half gallon jar) into your clean jar. Top off the jar with your plain milk. Tightly screw lid to the jar and shake vigorously for 1 minute. Place in a warm (but not hot) area out of direct sunlight.
So if you are baking cakes, cupcakes, biscuits, and such and looking for it to be even more similar to real buttermilk, use heavy cream or half heavy cream and half milk so it's just as thick as buttermilk, then add in the vinegar. ... All will work well in many recipes no matter what type of milk you choose to use.
Some common traits of bad buttermilk are a lumpy texture, a slight discoloration and a very distinctive unclean sour smell. If you notice any of these changes, your buttermilk has gone bad and should not be used.