“The Best Killers of Other Bacteria”
Here’s good news about food safety for those concerned about outbreaks of E. coli and salmonella in the U.S. food supply: no fresh or preserved food is safer than food fermented with lactic acid bacteria.
Ideally, grow your own produce or get it from a well-run local organic farm (that doesn’t allow the groundwater to be contaminated with fresh manure or sewage, for instance). Second, use common-sense good hygiene practices. Third, get started with home lacto-fermentation for safe preservation plus a boost in the nutritional value of the vegetables.
Cabbage, the basis of sauerkraut (from “sour cabbage” in German), multiplies its Vitamin C content when lacto-fermented, that is, brined while lactic acid cultures (lactobacillus) multiply, metabolizing the carbohydrates in the cabbage and any other vegetables or fruits included. You’re left with a tasty treat that enhances digestion, boosts the immune system, and supplies essential nutrients and friendly microflora. And, it keeps well, typically 6 months or so in the refrigerator.
The following is excerpted from a San Francisco Chronicle story, “Cultivating Their Fascination With Fermentation,” originally published June 7, 2009, by Tara Duggan, on the safety of lacto-fermentation.
U.S. Department of Agriculture research service microbiologist Fred Breidt says properly fermented vegetables are actually safer than raw vegetables, which might have been exposed to pathogens like E. coli on the farm.
“With fermented products there is no safety concern. I can flat-out say that. The reason is the lactic acid bacteria that carry out the fermentation are the world’s best killers of other bacteria,” says Breidt, who works at a lab at North Carolina State University, Raleigh, where scientists have been studying fermented and other pickled foods since the 1930s.
Breidt adds that fermented vegetables, for which there are no documented cases of food-borne illness, are safer for novices to make than canned vegetables. Pressurized canning creates an anaerobic environment that increases the risk of deadly botulism, particularly with low-acid foods.
Sterilizing jars or crocks for sauerkraut or pickles is optional. It’s OK to simply wash the jars in hot, sudsy water. Make sure that the food is completely submerged in the brine – some recipes call for weighting down the vegetables. Earthenware pickle crocks from Germany, such as Harsch brand, are designed to keep oxygen out but allow the undesirable carbon dioxide to escape. Canning jars work fine, too.
I’ve made a few batches of sauerkraut and even kimchi, and while they didn’t all turn out great, they were all edible. (My boyfriend claims to prefer mine to those from Three Stone Hearth in Berkeley, which is high praise indeed. My own favorite is Cultured, also from Berkeley.) I’ve since made lacto-fermented salsa, and I always culture my homemade mayonnaise with whey drained off Strauss whole-milk organic yogurt. It stays fresher longer and doesn’t change the flavor.
I got my start on culturing when I sat in on an introductory workshop on making sauerkraut and kimchi by Sandor Katz, the author of Wild Fermentation, at Rainbow Grocery in San Francisco a few years ago when he was promoting his book. That changed my life! I started experimenting with making sauerkraut, while learning to like the taste at the same time. I had previously only tried the canned stuff, which has all the goodness (beneficial live microorganisms) cooked out and resembles raw, homemade sauerkraut the way canned peas resemble fresh peas from your garden.
Wild Fermentation got me started with my fascination with the invisible world all around us—and on us, and in us—of beneficial microorganisms. Most of them are beneficial or at least not harmful, and controlled fermentation harnesses the good ones for our own culinary and medicinal purposes, while killing off the competition.