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Come in, sit down. We last had a little chat about pasteurization when we were talking about raw milk. Milk in stores is pasteurized to kill microbes that could make you sick, but occasionally people will seek out “raw” milk that has skipped this process. (This is a bad idea. Do not do this.) Now that it’s apple cider season, health departments are begging you to realize that the same issue applies to cider.
What is pasteurization again?
Cider, and certain other food products, can be treated with heat pasteurization, which is a procedure that uses ultraviolet light to kill microbes.
Traditional (heat) pasteurization is a process in which food is brought to a high temperature, usually 140 degrees Fahrenheit, for a long enough time to kill bacteria. Notably this is not the same temperature as boiling (212 degrees), so you don’t get the same taste or texture effects as if the food were boiled. For example, eggs can be pasteurized, and they may have a slightly more opaque white than raw eggs, but they are still raw and you wouldn’t confuse them for hard-boiled eggs.
The process, named for pioneering microbiologist Louis Pasteur, was originally invented to stop the fermentation process in wine and beer. (As the microbes continue to ferment the wine, it becomes more sour.) Today, it’s commonly used on many food products, and can also be done with ultraviolet light instead of heat.
Nearly all milk sold in grocery stores is pasteurized. (Depending on your state, raw milk is either a specialty product or completely illegal.) The same goes for most fruit juices. If you’re buying the cheapest or most common products from your local big box store, you don’t have to worry about this.
How do you know if your apple cider is pasteurized?
If you buy your apple cider in a shelf-stable bottle at the grocery store, you can expect it to be pasteurized. (Check the label to be sure; unpasteurized juices, including cider, are required to carry a warning.) But if you go to a farm to pick your own apples or enjoy a hayride to the pumpkin patch, you may be offered a cup of farm-fresh cider.
Many farms and orchards pasteurize or UV-treat their cider, but occasionally they don’t. Food Safety News cites two E. coli outbreaks, in 2015 and 2017, both from apple cider served at California orchards. One sickened seven people, the other 13. (You can read a CDC report of the 2015 outbreak investigation here.)
If you drink apple cider from a farm, juice bar, or anywhere else where you can’t see a label, make sure to ask whether it’s been pasteurized. Some farms use terms like “UV-processed” instead of pasteurized, but they should be able to tell you what that means and whether it’s compliant with local health regulations.