Pasteurized? Homogenized? Grass-fed? How do you choose the best milk for making yogurt?
What is Pasteurized Milk?Pasteurization is the process of heating milk to kill bacteria, making the milk stay fresh longer. While this process may have made milk easier to transport long distances, it may not be the best for milk you're going to use to make yogurt. There are different types of pasteurization, so be sure to check the carton before you buy!
- HTST or Flash Pasteurized milk is heated to 161ºF and held there for 15 seconds. If your bottle of milk is labeled simply Pasteurized, it has most likely been treated in this way. Pasteurized milk is a great choice for making your own yogurt at home.
- UHT or Ultra-pasteurized milk is heated to 284ºF for 4 seconds. Ultra-pasteurized milk is actually sterilized milk, giving it a shelf-life of several months, with no refrigeration required. Sterile milk, though widely available, is not a great choice for making yogurt. Don't be fooled by the organic label, either. Many major brands of organic milk are also ultra-pasteurized. Steer clear of them all, especially for making yogurt.
What about Raw Milk?
Raw milk may or may not be legally available in your state. Some states have outlawed raw milk altogether. Others, like Oregon, have various restrictions on sales. California, Washington, and other states have no restrictions on raw milk retail sales. Check this interactive map for your state's rules on raw milk. Raw milk can easily be used for making yogurt, usually with an extra step to keep the reusable starter true.
Can I Make Yogurt With Non-Homogenized Milk?
Most store-bought milk is homogenized. That means the cream or fat has been broken down into minuscule portions that are dispersed evenly throughout the milk by pumping milk through small openings under very high pressure. The fat content of homogenized whole milk (3.25%), reduced fat (2%), low-fat milk (1%), and skim milk (0%), have all been standardized by the dairy industry. Non-homogenized milk, however, has a nice cream layer on top of the milk, just like it comes out of the cow. Yum! The fat content varies depending on time of year, type of cow, diet, etc. Milk with the highest fat content makes the creamiest yogurt. Many local dairies offer cream-on-top milk, a great choice when making your own yogurt at home.
What is the Deal with Grass-fed Milk?
Be wary of the colorful carton with a pretty cow on the side. That new brand of grass-fed milk is often ultra-pasteurized. Some stores even stock different sizes of the same brand in the same area, with some ultra-pasteurized and some pasteurized. Always read the label!