What is Lacto-Fermentation?
In lacto-fermentation, salt is added to vegetables, either by covering them in salty water or by mixing them with salt to draw out their own juices. Lactic microbial organisms (the same beasties that spoil milk) grow in this environment and generate acid so that the bacteria and molds that cause food to spoil can’t reproduce. Sauerkraut is the best known example.
For more details of the complex Lacto-Fermentation process see:
It’s helpful to read that info although few of us will understand even half of it. If you know a little about the whole process it will help you understand variouis recipes and let you judge if the author is someone you should trust.
- Need to tightly pack the vegetables and weight them down to keep them away from oxygen. This isn’t quite as critical if you’re using an air-lock system.
- Need to keep the vegetables completely covered by a 3.6% salt brine but not by more than about an inch. Too much brine dilutes the acid being produced.
- Need to keep the vegetables away from light. A dish towel draped over a glass jar is sufficient if it doesn’t get hit with direct sun.
- The fermentation container should not be tightly sealed. CO2 is generated and could break the container.
- Need to keep the vegetables between 68°-72° for the first few days.
Summer isn’t the best time for lacto-fermenting foods.
68° to 72° is the ideal temperature for the first 2 to 7 days of Lacto-Fermentation. You may see CO2 bubbling during this period. If it’s warmer, spoilage or mold may occur before the fermentation can generate sufficient lactic acid.
For best flavor, move the fermentation to an area with a temperature of 59 to 64° for another several weeks. Make sure the brine still covers the vegetables. (You can shorten this step but the flavor and acidity won’t be as fully developed. You may like the taste–it just won’t store as long.)
After that, store in the refrigerator or another area with a temperature between 41 and 59°. At this point, I move the vegetables from the fermenting container into plastic or glass jars. Make sure the brine still covers the vegetable. Little gas is produced at this point but I occasionally burp the jars to make sure pressure isn’t building up.
Is It Safe?
Excerpt from a San Francisco Gate article, June, 2009 —from the Pickl-It website
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 food”
The problem is if Lacto-Fermentation didn’t occur in the first few days. Wrong brine strength, wrong temperature, chlorinated water, iodized salt, or a vegetable that is difficult to Lacto-Ferment–meaning you can’t find a recipe anywhere saying it has been successfully done before.
“The finished product should simultaneously taste sweet, salty and sour. It shouldn’t sting your tongue or have a weird or sharp
aftertaste. If it does discard it! When in doubt, throw it out! If the brine tastes good, use a clean spoon or fork and taste a small amount of the vegetable. Again, it should taste sweet, salty and sour and shouldn’t sting your tongue. If it tastes or feels bad throw it out!”
–Lacto-Fermentation Through the Seasons, The Art of Old-fashioned Salt brine pickling, www.food-medicine.com
But that doesn’t mean you should taste anything that’s obviously spoiled or smells foul! The botulinum toxins as a group are among the most toxic compounds known to man. Some of them create a foul smell and some don’t.
Don’t use less salt than recommended in modern recipes. The salt keeps the fermentation safe–especially in the first few days.
Like canning, if you don’t read and learn about Lacto-Fermentation from a variety of sources; there’s the possibility of the process going awry. A little white/gray mold on the surface usually doesn’t indicate a problem–just scoop it off. If the mold is red, orange, or black, throw it out.
Making sauerkraut from cabbage is a good place to start. It’s easy and you know what it’s supposed to look, smell, and taste like.
Pickling vs Lacto-Fermentation
Lacto-fermentation does not involve recipes that use vinegar. While Lacto-fermentation is sometimes referred to as pickling, most modern pickles are made with vinegar and are not Lacto-fermented. Preserving vegetables in a vinegar and salt mixture is a tasty-easy-safe method for vegetables but the flavor will be different and the purported health benefits of lacto-fermentation won’t be there.
Fermentation is a batch process. You must add everything at once and then leave it alone. You can’t add a little today and more tomorrow–a vinegar and salt pickling solution is good for that.
Lacto-Fermentation Health Benefits
Both of the popular books with fermentation recipes listed in the handout make health claims for fermented foods. I have no idea of the validity of those claims–just that lacto-fermentation is an ancient technique for preserving food and I like the taste of sauerkraut.
Both books are useful in presenting a variety of different vegetables that can be lacto-fermented. Sally Fallon’s recipes add fresh unpasteurized whey to jump start lacto-fermentation and she reduces the amount of salt. Most sources don’t think fresh unpasteurized whey is necessar–and fresh whey isn’t easily available. If you use Sally’s recipes without using whey, you’ll need to adjust the salt per her instructions.
The recipes that I find the easiest to follow are the ones on Pickl-it.com. (Rather than saying add 1 TBL salt to a medium head of cabbage, they specify adding 3TBL to 5 pounds of cabbage.)
Salted Cabbage makes sauerkraut
Cabbage is unique in that it makes it’s own brine when salted.
Rather than layering salt and cabbage in your container as called for in most recipes, you may find it easier to mix the weighed cabbage and salt together in a large bowl, let it rest for 15 minutes, remix, and then firmly pack it and the juice into the fermentation container. Add a weight to keep the cabbage packed down under the liquid.
Within a few hours enough liquid should move out of the cabbage to cover it and the flat part of the weight by 1/2 to 1 inch. If not, add a 2.5% brine to cover. For a full recipe and techniques, consult one of the references below.
Brines for Lacto-Fermentation of vegetables other than cabbage
• 5.4% brine formula = 6 tablespoons canning salt to 8 cups water.
Good for pickles. Pickles are prone to spoilage. Normally eaten in small quantities so there’s less dietary need to minimize salt.
• 3.6% brine formula = 4 tablespoons canning salt to 8 cups water.
The standard modern brine used for vegetables. Some old recipes use a lot more salt.
• 2.5% brine formula = 1 tablespoon canning salt to 3 cups water
Use for topping off cabbage when the cabbage doesn’t provide enough liquid within a couple of hours to cover itself.
* A crock with a weight the diameter of the crock to keep vegetable compressed and covered with brine. This is the traditional way to make large batches of kraut. The weight can be: a plate with a jar of water on top, a wooden “kraut-weight” with a clean stone on top, etc. Lehman’s sells wooden kraut-weights. Some recipes recommend using zip-lock bags as weights–I haven’t had good luck with that–mold tends to form along the sides and it’s hard to remove the mold between the bag and the container.
It’s best for newbies to start with a 3 gallon crock–wait until you have some experience to make large batches. You’ll have the best luck if your fill it at least half-way but not more than 2/3 full. The fill-level can move up and during the early days of fermentation
* A jar with an airlock such as that sold by Pickl-It.com. You can make your own with an airlock from any home-brewing supply store. Buy a grommet at the hardware store to snugly fit the airlock and drill a hole through the lid. The air-lock keeps the oxygen out and makes tightly packing vegetables less important. Cabbage packs tightly–peppers not so much.
A clear container allows you to see what’s happening which is useful for newbies. Keep covered with a towel or in the dark.
I recommend the Pickl-It.com site and an airlock system (purchased or handmade) for those just starting with fermentation. It’s also a good way to make small batches of fermented peppers, etc.–anything that won’t pack tightly.
* A Harsch Crock with a water lock and split stoneware weights.
Big and heavy. Hard to get the fermented food out. Available from many sources. Here’s a link to Amazon:
The best (and free) source of techniquies and recipes suitable for beginners. They sell an airlock system or you can create your own. Don’t buy their system without the optional Dunk’R glass weight to help hold food under the brine. You’ll need to leave space above the shoulder of the container–otherwise the food expands and pushes liquid out the airlock making a mess. A big advantage of a clear container is that you can see what’s happening–although you need to cover the container with a dark towel or keep it in the dark.
* Sandor Katz’s book: Wild Fermentation (Somewhat controversial–read the negative reviews on Amazon)
Info and Fermentation Support Forums–helpful reading and you can get questions answered.
* Sally Fallon’s book: Nourishing Traditions. She has 20 pages of fermentation recipes using whey. (Her book is somewhat controversial–read the negative reviews on Amazon)