For some time now, I’ve indulged in this little lopsided love affair with Saveur magazine. Monthly, the publication winds up in my mailbox, and I find myself unable to resist an immediate flip through the pages. How can a foodie not fall in love? I mean…the delectable photos (and yummy recipes) practically make you want to EAT the paper. Not that there was any question, but the October issue didn’t disappoint. My favorite article this issue? A spread on live-cultured food products. When I realized I haven’t yet posted on this very cool food science secret, I opened my laptop and started punching out a post.
Thanks to the ever-present promotion of “probiotics” and “good gut health,” it’s not just healthniks anymore who are familiar with live bacteria in the yogurt aisle. But, as the Saveur article reminded me, the world of live-cultured foods is so much more inclusive. (Sorry, Jamie Lee. ) Products such as sauerkraut, sourdough bread, soy sauce, chocolate, kimchi, kefir, cultured butter, and pickles are other tasty examples of products that can be live-cultured. So, what’s the science behind live-cultured food products? Fermentation.
During fermentation, microorganisms (yeasts, bacteria, or a combo of the two) alter the properties of a particular food product by consuming sugars and producing carbon dioxide, acids, or alcohols. (With alcoholic beverages, we pretty well know what the buzz is all about – yeasts transform the sugars in grains/fruits, and beer or wine is the resulting product. Check out Oh Vino and Wassup with Beer for a bit more info.)
Sauerkraut is a great example of a live-cultured product. Cabbage is chopped and dropped into a salty brine, and the present bacteria ferments the sugars into lactic acid. (The lactic acid gives our favorite sausage-topper that characteristic sour flavor profile.) Sourdough bread is a classic example of yeast and bacteria working together in fermentation – the yeast consume sugar and produces bread-rising gas, and the fermenting bacteria lends to the sour taste. Of course, yogurt production is similar science. After pasteurization/homogenization (to kill pathogenic bacteria), the milk product is inoculated with a starter culture and the bacteria starts to ferment, resulting in lactic acid (and a coagulated texture and tangy flavor).
Much to my surprise, it seems live-cultured foods are making a comeback in many home kitchens as foodies begin to experiment with homemade yogurts, pickles, beers, etc. That’s right…we all love a good, geeky, gas-producing kitchen experiment. But before you fellow foodies embark on new fermentation adventures, be sure to note: time/temperature controls will become critical to the success (and safety) of your food product. (Commercially produced products have stringent controls on starter cultures and processing.)