Sometimes, when reading on the internets, I’ll see some stuff about how kombucha is such a delicious lactofermented beverage, or how it was amazing to find out the even chocolate and vinegar are lactofermented (or worse “probiotic.” They’re not.)! Those things are all fermented, of course, but they are not lactofermented. I totally understand the confusion, so I thought I would offer a little cheat sheet on which common fermented food goes with which type of fermentation.
Lactic Acid Fermentation
Lactic acid fermentation is so called because of its lactic acid bacteria. These bacteria are call lactic acid bacteria (LAB) because they produce lactic acid (shocker) and not because they have any milk or dairy products in them. Lactic acid bacteria are present in the soil, and therefore on the things that grow in the earth. There are also strains of lactic acid bacteria naturally present in dairy milk. Lactofermented foods are the foods that can be called “probiotic” based on their production of health-enhancing bacteria.
Some Favorite Foods Made Through Lactic Acid Fermentation (lactofermentation):
- Sauerkraut
- Kimchi
- Pickles, including cucumber pickles and all pickled vegetables (these can also be canned, not a fermentation process)
- Yogurt
- Cheese (some cheeses are further fermented with molds, see below)
Yeast Fermentation
When we talk about yeast fermentation, we’re talking about the metabolic activity (think: eating) of yeast on sugars. When yeast eat sugar, they create waste products, most specifically CO2 and alcohol (ethanol). The CO2 makes things bubble. The ethanol makes you drunk.
Some favorite foods made through yeast fermentation:
- Beer
- Wine
- Bread (sourdough bread is a mixed ferment that involves both yeast and lactic acid bacteria. It’s not probiotic, though, because the bread is baked at a temperature that kills the good bacteria).
Acetic Fermentation
Acetic fermentation is pretty crazy, because the bacteria responsible for this kind of fermentation live in the air and make their way in the world as booze-hounds. Acetobacter, the genus of bacteria that readily make acetic acid from alcohol, consume the ethanol in wine, cider, beer, etc and make it into tasty vinegar. They require air to do their work, which is kind of an odd thing about them in the fermentation world (the biological definition of fermentation usually contains the word “anaerobic” (airless).) That’s why when you’re making booze or wine, you definitely want an airlock in the mix. If acetobacter in the air get in there, they’ll turn your lovely wine into (possibly also lovely) vinegar.
Some favorite foods made through acetic fermentation:
- Wine Vinegar
- Malt Vinegar
- Apple Cider Vinegar (or other fruit vinegars)
Bacteria/Yeast/Mixed Ferments
SCOBYs are physical cultures that combine the fermentation powers of both yeast and bacteria as their name, an acronym that describes that relationship (Symbiotic Community of Bacteria and Yeast), suggests. These guys typically work together to create their physical structure, a matrix of cellulose. In the case of the kombucha SCOBY, for instance, these microbes work together in interesting ways. The yeast consume the sugars in the tea drink and produce waste products which are in turn consumed by the bacteria and used to create more SCOBY and tasty kombucha.
Some favorite foods made through symbiotic fermentation*:
- Kefir
- Water Kefir
- Kombucha
- Ginger Beer Plant
- Sourdough Bread
- Ginger Bug (with all the added sugar, this one likely veers more into yeast ferment territory, but I’ve definitely made a few ginger beers with some lactic bite)
Mold Ferments
Other than cheese there aren’t a whole lot of moldy things or mold-fermented things that we Americans eat on the regular. There are some truly delightful and traditional ferments hailing from Asia that fall into this category. They can be a little trickier to ferment, and may require more patience or equipment (or at least spores), but they are often worth the elbow grease!
Some favorite foods made through mold fermentation*:
- Tempeh
- Koji (which makes miso, sake, amazake and soy sauce)
- Some cheeses
*That is not an actual term, nor is it a true “type” of fermentation. It’s two different types of fermentation happening in the same food/drink. There are plenty of ferments that have multiple kinds of fermentation happening at different times, or even overlapping. This isn’t intended to be a full, scientific accounting, but rather a little overview that laymen can use to talk or write about their ferments.
dino says
Excellent summation in simple language of the various types of fermentation.
dino says
An excellent overview of the processes & types of fermentation!
Tracy Boudrie says
VERY interesting!!!!! Thank you for the thorough clarification!!
Petter says
You should totally add lambic/gueuze or other Belgian sour beers to your list of yeast/bacteria fermentations. The authentic versions are delicious!
Handful says
I did not realize there is a difference. My question: is there probiotic goodness in ALL types of fermentation?
Ii have only been fermenting goodies (other than kraut) for a bit over a year.
Amanda says
Hi Handful,
Great question! No. Probiotic ferments are lactic acid ferments and some of the “mixed culture” ferments I mention above. Ferments that are just yeast/mold/acetic ferments are not probiotic. That doesn’t mean that there is no reason to consume other ferments, or that they can’t have other healthful enzymes or properties, but it does mean that probiotic is an incorrect way to refer to them.
Loraine Lerumo says
I am just learning. Being new in the field I am amazed at the wealth of information about fermentation. What would be the best bacteria for sour bread.
Amanda says
Hi Loraine,
Are you looking to make sourdough bread (like with a sourdough starter aka natural leaven) or to experiment with different ways to sour bread? If you’re looking for sourdough info, I did an in-depth series at the start of this year that you may want to check out!
http://phickle.com/sourdough-starter-school-step-1-tartine/
Thanks for reading!
Izzy says
I love this simple breakdown – super informative, thanks!
Reine says
I have been searching all over for an answer to maybe an odd question. I tried making lacto fermented ginger ale with whey – it did not fizz. I have a few extra scoby. Is it possible to ferment ginger ale with a scoby if I mix in some Kombucha tea with it? I used ginger root, sugar, whey already. Thank you for any insights. One of the most informative articles I have read yet on explaining it simply.
Amanda says
Hi Reine,
So the whey thing should work. The only times I’ve had issues with this is if I haven’t used “fresh” whey (grocery store yogurt whey = useless, for instance, whereas freshly strained kefir whey = super bubbles!), haven’t used enough sugar or haven’t carbonated in a bottle that traps carbonation. So possibly try one or all of those things.
To answer your actual question, you can make ginger kombucha and it’s incredibly tasty. It chocolate and peanut butter levels of “supposed to be together”-ness. I wouldn’t just add a SCOBY to ginger water and sugar (unless it’s a spare SCOBY and you just want to play around, it is totally possible that it could work). What you can definitely do, though, with excellent results, is add lots of grated ginger and a little sugar to your kombucha during secondary fermentation. That will really be ginger booch and not ginger ale, but it’s mighty tasty all the same!
george wilcox says
Mold is used for salumi. Not just cheese.
Amanda says
Hi George,
Hmmmm. Mold definitely grows on salami, but salami is actually a bacterial ferment. I’m not expert, only having made it a few times, but none of those times was my salami innoculated with mold.
Haz says
Hi there, I love the summary given for each fermentation. It gives me an idea on which to dive in. However, I would like to clarify something, do all these fermentation produce alcohol? I was told by a friend that all fermentation produces alcohol so I was quite perplexed. Religiously, I am not allowed to take alcohol so are there any fermentation method that does not produce alcohol? I would like to take in more probiotics. There shouldn’t be any in yoghurt and tempeh right? These are actually two of my fave food. 😀
Amanda says
Most of the fermentation I’ve done does produce trace amounts of alcohol. This includes things like bread, sauerkraut and yogurt.
I’m honestly not sure if alcohol is a by-product of all food fermentation, but it is definitely common. I wish I could tell you “No” but I can tell you that these are generally small amounts of alcohol, low enough to be legal to sell without labeling in the US, aka below .5%.
Heather Hatch says
I also do not consume alcohol for religious reasons. I feel comfortable consuming lactofermented vegetables. I just found out that my church, which actually owns/manages dairy farms ferments the feed they give to the animals. The feed is fermented for 30 days. I figure if they think it’s healthier for the dairy animals to consume fermented feed than it’s okay for me as well.
Vikki K says
I am wondering if a fruit salsa or fruit kimchi or cabbage & apple kraut are included in the lactic acid ferments by virtue of being combined with vegetables? I also did a sweet & sour apple with brine, lemon juice and cinnamon sticks – would that be lactic or yeast or combination?
Amanda says
It really depends on the proportion. If it turns sour, it’s likely bacterial. If it turns into booze, it’s a yeast ferment.
The apple thing may or may not have fermented, depending on how much lemon juice you used, and if it did ferment, the level of salt would be important for ensuring that it’s a lactic acid ferment. If the brine didn’t get slimy or boozy, you were likely in the lax realm (or it just infused and didn’t ferment).
I hope that helps!
Gahariet says
So does lacto-fermentation require sugar? For instance, to make lacto-fermented lemonade I would add lemons, water and whey. But some recipes call for sugar. Is this sugar going to be eaten by the lactobacteria?
Amanda says
Hi Gahariet,
Lactic acid bacteria eat and convert sugars, but usually those are naturally present sugars that come from the vegetables themselves. For something like lemonade that would be more of a fun project than a wild ferment, adding sugar will feed both the added culture and also make it drinkable. (Lemon juice highly concentrated in water would be too sour for most of us to down without a bit of sugar to dull the edges).
Robin says
Thanks for this great article. What is the fermentation process in Tepache? It seems to be a combo of yeast (found on the skin) and acetic fermentation (from the wild) but I’d appreciate your view. Thanks.
Amanda says
Tepache would definitely be a yeast ferment. Sugar is generally added, and the sugar from the pineapple alone would definitely be enough to make those yeasts happy. Like all wild ferments, there’s probably some crossover, so you maybe be getting a dose of bacteria, but this primarily a yeast ferment that will turn to wine if fermented for long enough. I hope that helps!
Lena says
Hello! Thank you for this clear summary of this amazing world of the tiny that change everything!
I have a question: staying for long in South east asia, I had often coming to my noose the familiar smell of swiss cheese. That was from “fermented” (but maybe not fermented?) fish. So here comes my question, where would you put it?
The shrimp paste is made with salt and put in airtight jars for several months. This is lactic fermentation to me.
Another question, about time: I see “pickles” recipes, that involve putting vinegar with salt and vegetables. And it’s ready in a few days. Is it lactic fermentation or just a fast way to give a sour taste to copy a proper lactic fermentation? Can acetic fermentation prevent or promote the rise of the lactic bacteria?
Sorry I am asking very tough questions, but maybe you know where to find the answer.
Thank you and good job for your nice blog!
Lena
Amanda says
There is totally a swiss or parmesan cheese associated with fish sauce, which is indeed fermented! And a favorite in my home :-). I’m not sure I understand the question about where to put it? If you mean during fermentation, I have never made fish sauce, but I know that many people store the fermentation vessels in their basements, where the smell isn’t in the living parts of the home.
Vinegar pickles are not fermented. Acetic fermentation may or may not inhibit fermentation (meaning it is POSSIBLE that you could get some fermentation happening in vinegar if you left it sitting out on the counter, but I wouldn’t count on it, because the beginning stage bacteria responsible for vegetable fermentation aren’t super happy in a high acid environment, and using vinegar rather than salt brine could definitely mean that the enviroment is too acidic for ANY bacteria usually involved in lactic acid fermentation. It would certainly not promote lactic acid fermentation.
I did write a post a while ago about the differences between canning and fermentation, and there’s a section in my book on it as well.
Sharon says
Wow, thanks so much. I’m just starting in the fermentation arena and sit with wide eyes feeling quite overwhelmed but enthusiastic. This helped put things into perspective for me!!
Amanda says
You’re very welcome! I hope you move forward without intimidation! You’ve totally got this!
Mark says
Can you use lacto fermented sauerkraut whey to make yogurt or kefir? I am making my first batch of sauerkraut and would also like to make yogurt since I am lactose intolerant and store bought makes me sick. So I was wondering if the lactobacilli bunch could be used for that too, since it would be nice to not buy a starter culture if it is not needed. And if yogurt whey can be added to lacto fermented foods, then could it not be used the other way around? I have been searching the Internet for days and have not found an answer. If you, or someone you know, could answer this it would be greatly appreciated. Thank you
Amanda says
Hi Mark,
It’s a little complicated. Yogurt sets to a gel, rather than a liquid because of the byproducts of specific bacteria involved in its culturing. Those bacteria are (probably) not present in your sauerkraut, so while you would culture the milk (and be salting it!) you wouldn’t be culturing it with the “right” bacteria to make yogurt. The bacteria responsible for vegetable fermentation are generally comfortable/happy at room temp, while thermophilic yogurt cultures need temps above 100 F to do their jobs properly.
I don’t recommend using yogurt whey to make sauerkraut, either. Even though it works, it has been shown to negatively impact texture and microbial diversity. Anecdotally, it also leads to more issues with surface growth and brine texture than I’ve ever seen in wild fermented veggies.
I hope that helps!
katy says
Thank you! This is a great overview. You’ve done a stellar job. 🙂
Mac says
Thanks for the great article. I’ve been experimenting with lactoferentation for about a year and really enjoying it. I’ve seen a couple of you-tubers who start their vegetable fermentation with probiotics either in capsule or powder form. One even reuses their brine with thick white bacteria over and over again, just adding sugar to feed the bacteria. Is this lactofermentaion? They don’t refrigerate or seem to worry about light and say it will last indefinitely. Where I usually leave them in a dark cupboard for a couple weeks then move them to the refrigerator. He also had a “mother brine” made from coconut water and a probiotic capsule that he uses to start new fermentations when he isn’t reusing old ones.
Amanda says
Hey Mac,
I never use a starter for vegetable fermentation, because it will start itself and provide the right probiotic bacteria. I wrote a post about this that you might enjoy!
tianJo says
This is a great summary. About the alcohol issue, I am still a little confused. I would not think that the products which are strictly lacto-fermented would turn to alcohol, but those using some amount of yeast (kefir, kombucha, etc). Is this not correct? You state that your yogurt had trace amounts of alcohol…how did you test it? Thank you.
Amanda says
Hi Tianjo,
It’s not that I tested my yogurt, it’s that early stage lactic acid bacteria produce alcohol, so we know it’s in there. They produce small amounts (unlike yeast), but still, foods fermented with l. mesenteroides will have trace amounts of alcohol. Alcohol is generally produced in the earlier stages of fermentation when heterofermentative bacteria are more active as opposed to later stages when more specialized (and acid-tolerant) homofermentative bacteria are absent. You can read about this (with citations in Sandor Katz’ The Art of Fermentation).
I hope that clarifies!
Mia says
Hello! Thank you for an excellent review! What’s about brown rice fermented with only sugar, salt, and water (no yeast added)? Is it lacto fermented or yeast fermented like beer? Thanks.
Amanda says
Hi Mia,
In that case, I would say it depends on how much sugar vs. how much salt and what the process of fermentation is. I could see you ending up with a rice wine if you stirred enough early on, airlocked it after that phase and didn’t add any salt.
Dusty says
Great article – And wonderful site. I will likely be spending a few days of research here. I’m a long time brewer (beer) and home wine maker. I make a lot of sour beers, using lactobacillus. I have a few questions for you if you have a sec.
I’ve thought about using a kombucha mother/scoby to sour a beer, but am afraid it won’t work. First, with the longer aging I would need to allow for the beer to go through, I’m afraid the scoby would continue to work through the alcohol? Also, without the presence of tea in the solution, I’m assuming the scoby would not work as it normally would?
Amanda says
Hey Dusty,
I would recommend trying this with a small batch! The SCOBY-dwellers will likely continue to chomp on the booze present, and my best guess is that you’ll end up with something akin to malt vinegar, but I have never tried, so who knows!
People often adapt SCOBYs to other substrates (fruit juice, tisanes, etc), so you could try it! It definitely will need a decent amount of sugar, though, so you might want to consider adding a bit.
If you do this, please report back. I’d love to hear how it goes. And def use a small batch. I’d hate for you to end up with 5 gallons or more of something you don’t want!
Jennifer says
Great blog post! Thank you for clarifying the differences in fermentation. I started fermenting a few months ago. Kimchi and raw milk yogurt are staples in my fridge now. I’m about to start making kombucha. I’m also taking an Intro to Organic Chemistry class at the local college and I feel like I’ve stumbled into a vast world full of wonders! Do you mind if I ask what your education background is? You have a gift for making these complex ideas simple to understand. 🙂
May says
Hi love your blog, I’m allergic to yeast so I was wondering if fresh yeast would be better like sourdough starter. I’m just trying to find an alternative.
Thanks may
Amanda says
I don’t think it would be any different. I’m not sure how a yeast allergy “works” for lack of a better term, or how much the proteins vary from one yeast strain to another. My guess would be that a wild yeast would be generally made up of more diverse yeast strains than a commercial yeast, which seems like it would be worse for you, rather than better.
I can’t say for sure, but if it were me, I would avoid. (So sorry!)
Ann says
I regularly make lactofermented vegs/fruits and homemade wines. I used to make vinegars from leftover wines and beer so acetobacter was present in my environment and some of my good wine turned vinegary after awhile. I keep the mother tightly sealed these days and only use on occasion. In the fall I like to make apple wine from locally grown apples. In a warm kitchen, 7-10 days for the fermentation to stop (or nearly) and then it’s time to rack. I also make umeboshi when I can find the right fruit. I made a batch of lacto plums from store-bought to make plum sauce and for the leftover ume-zu (brine). That was a fun ferment. Since I make wine, some of the yeast floating around made its way into the ferment. This created alcohol from the natural sweetness of the plums. That’s ok. That alcohol is a natural preservative. Koji is fun to play around with. I have added yeast to kombucha to boost the alcohol content. Most of the time when you walk into my home, the smell of some type of fermentation is noticeable. Wish I had a special room just for this fun and nutritious hobby!