Many people use buttermilk to make pancakes, biscuits, salad dressings, and smoothies for both health and taste. Buttermilk can substitute in most recipes that call for milk to lend richness and flavor. However, buttermilk is often two or three times more expensive than regular milk by the gallon.
The good news is that you can make your own with no special equipment and little trouble because microscopic bacteria do all the work for you! Making your own buttermilk is a good way to use milk that is just on the verge of going sour and it’s also a great project to do with your children.
The Science Made Easy
Buttermilk is tart because it is acidic due to fermentation. The helpful bacteria use enzymes to release energy from lactose (a form of sugar found in milk) in the form of ATP and produce lactic acid.
Buttermilk is thick because casein (a form of protein found in milk) isn’t soluble at the increased levels of acidity and it precipitates. This is similar to what happens when you find sugar at the bottom of your iced tea. The thickening process is called curdling or clabbering.
The most common bacteria found in buttermilk is Lactococcus lactis but others such as Lactobacillus acidophilus and Leuconostoc citrovorum are frequently used. These and related bacteria are often referred to as “probiotics” and are sometimes recommended to help restore the natural intestinal bacteria after taking antibiotics.
As a special benefit, many people who are mildly lactose intolerant are able to drink buttermilk because the bacteria have already broken down the lactose for them.
How to Make Buttermilk
You need a clean container made of glass, metal, or food-grade plastic. Canning jars or plastic food containers work well. You can even re-use cottage cheese or yoghurt containers. You also need milk and some live or active culture buttermilk as starter.
Tip: You can use skim, reduced fat, or whole milk. Make sure the buttermilk label indicates that it has live or active culture and that it is fresh.
Pour one part of live culture buttermilk into three to ten parts of regular milk. For a gallon of milk, a pint of buttermilk works well. For a quart of milk, a half cup of buttermilk will do nicely.
Tip: The less buttermilk you use, the longer it will take to ferment. Fresher buttermilk also works faster because it has more live bacteria. Just a couple of tablespoons of fresh buttermilk will turn a whole gallon of milk into buttermilk given enough time.
Shake or stir the contents of the container to mix well. Let it sit overnight or for 24 hours.
Tip: If the room is cold, find a warm place to put the container such as on top of the refrigerator.
After the buttermilk has thickened and become tart, you can add a pinch of salt to taste if you will be drinking it plain.
Buttermilk keeps much longer in the refrigerator than regular milk because the acidity prevents harmful bacteria from growing. Any mold that grows on the container is similar to the mold on cheese and doesn’t ruin the buttermilk.
After you make your first batch of buttermilk, you can use it as starter for the next batch.
Bonus Tip: To make sour cream, start with whole cream instead of milk and follow the same procedure.
Enjoy Your Buttermilk
You’ll find lots of ways to enjoy your fresh buttermilk. A buttermilk banana blueberry smoothie is a nice treat. Just blend a cup of cold buttermilk with a frozen banana and a handful of frozen blueberries. Children may prefer it with a little sugar or honey added and adults may like a little fresh ginger grated in.