What is Buttermilk?

Buttermilk is one of the most commonly used dairy products. Apart from being used as a beverage, buttermilk is also used as a leavening agent in baked goods.
Tastessence Staff
Buttermilk is a dairy product produced by fermentation of milk. Traditional buttermilk is the liquid left behind after churning out butter from cream. This residual liquid is slightly sour in nature, and is topped with tiny flecks of butter, that fail to get skimmed out. It has a thin consistency and a light yogurt flavor. This buttermilk is consumed in different forms in different regions. Though uncommon to find today, this type of buttermilk was usually used by the people in warmer regions, where storing milk for longer periods was not possible. In countries like India, Pakistan, etc., this type of buttermilk is still made and consumed. Even in the warmer regions of the Southern United States, buttermilk has been used by the locals.
Nowadays, buttermilk is commercially prepared by fermenting pasteurized milk (whole milk, skim version, or low-fat versions). It is prepared by adding lactic acid bacteria culture to the milk. Once the culture is added, the milk is allowed to ferment for at least 12 hours, at a temperature of around 69° F. Such commercially prepared buttermilk is available in flavored and salted versions too. This type of buttermilk is thicker than the former. Traditional ones are paler and more sour to taste. While the fermentation process in case of traditional buttermilk is natural, in the newer version, culture is added. The sour taste of this dairy product is due to the presence of acid. To be more precise, during the fermentation process, bacteria acts on the sugars (like lactose) in the milk, to form lactic acid. This leads to precipitation of the milk protein casein, resulting in curdling. This is the process of buttermilk production.
What is Buttermilk Used For
Even though this dairy product has butter in its name, it does not contain butter. In some types, you may find tiny butter flecks. However, buttermilk has a very low fat content, and has less calories. While a glass of regular milk amounts to around 155 calories, the same amount of buttermilk contains only 98 calories. It is also very rich in vitamins and minerals. It is the high lactic acid content of buttermilk, which makes it easier to get digested. Being a probiotic that is rich in lactic acid bacteria, buttermilk is highly beneficial for the digestive system too.
While traditional buttermilk is a popular beverage in warmer regions, it is also used to prepare smoothies and other such drinks. Buttermilk mixed with a small amount of baking soda is found to be a good leavening agent, and is used in preparing baked goods, like cookies, waffles, biscuits, etc. Even ice creams are made with this dairy product. Buttermilk is also used for marinating chicken, as an additive in soups, and for making sauces.
If you run out of fresh buttermilk, you may use buttermilk powder. It is nothing other than buttermilk that is evaporated and dried. All you have to do is to mix ¼ cup of buttermilk powder in a cup of water. You may also prepare a substitute for buttermilk by mixing milk with white vinegar or lemon juice (one tablespoon for a cup of milk). Leave the mixture to curdle for at least ten minutes. Yogurt is another buttermilk substitute.