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Become a Fermentation Ninja – without Leaving Your Pajamas


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Eating fermented foods is one of the most important things you can do to improve your health. Fermentation increases the beneficial bacteria, vitamins and enzymes present in foods and makes the nutrients they contain more bioavailable. Our ancestors knew this implicitly: almost all traditional cultures that have been studied included fermented foods in their diet.

Fermented foods have powerful healing properties. I’ve written and spoken many times before about the importance of the gut flora, not only to digestive health, but also to the health of every system of the body.

Low levels of beneficial bacteria and high levels of pathogenic bacteria in the gut have been linked to everything from depression to acne to diabetes. This means that maintaining healthy gut flora is crucial to promoting optimal health, even if you don’t have any digestive symptoms.

I often hear from patients and readers that want to include more fermented foods in their diet, but they’re unsure of how to get started. Sure, you can buy at least some fermented foods at the grocery store. But that can get expensive quickly (my local Whole Foods charges nearly $10 a jar for raw sauerkraut, which costs us about $1 per jar to make at home), and there are many others such as water and dairy kefir, sauerkraut, kim chi and beet kvaas that many stores don’t carry. What’s more, fermenting at home gives you more control over the final product. This is important when you’re using fermented foods for healing purposes. For example, many people can’t tolerate store-bought yogurt because it still contains about 4.7% lactose. But if you make your own yogurt at home, you can ferment it for longer than the store-bought brands, which increases the amount of beneficial bacteria and eliminates all of the lactose.

Fermentation isn’t brain surgery, but it is both an art and a science, and there’s a learning curve involved (you should have smelled my first batch of sauerkraut). One of the best ways to learn a new craft is from a skilled teacher. Enter Jenny McGruther, creator of one of the best nutrient-dense food blogs on the web, Nourished Kitchen. I’ve been aware of Jenny’s work for some time, and I recently had a chance to meet her at the Weston A. Price conference in Santa Clara. Jenny told me about a new fermentation course she has put together call Learn How to Ferment Anything, and it seemed like a perfect fit for those of you that have asked about how to learn more about fermentation at home. Jenny is a master of fermentation, and I couldn’t think of anyone better to learn it from.

The course features:

  • 13 fermentation workshops
  • 50 instructional videos
  • Easy-to-follow print tutorials
  • Fact-sheets and troubleshooting tips
  • Regular Q&A conference calls
  • Email access to Jenny so you can ask her questions

This is by far the most comprehensive fermentation course I’m aware of. For example, you won’t just learn how to make yogurt, you’ll learn how to make Greek, Bulgarian and Scandinavian yogurts, raw milk and pasteurized milk yogurts and even coconut yogurt.   You’ll also learn how to make both dairy and water kefir, “tonic” probiotic beverages like beet kvaas, rejuvelac and sweet potato fly, fermented condiments like ketchup, mayonnaise, barbecue sauce and mustard, relishes and salsas, chutneys and vinegars, sauerkrauts and lacto-fermented vegetables, and a lot more.

CLICK HERE to learn more about the course and get started. Jenny is running a holiday special until 12/1. The code BLACKFRIDAY will take 40% of the cost of the course, so don’t wait too long.

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Join the conversation

  1. what are some of the best things to do for gallblader stones ??
    please advice
    thank you so much

  2. I don’t find your response to Ray Peat’s views very convincing, Chris. Cultures may have taken kefir for centuries, but that doesn’t mean it’s good for us. Yes , Ray Peat appears wacky on the surface. And that can make it easy to dismiss his views without giving any of his work due attention.

    If Kefir does contain significant lactic acid, are you saying that the science points towards it being insignificant or beneficial to human health? Because the studies that Ray cites show that it isn’t healthy. Lactic acid is highly inflammatory. Not saying that kefir is bad because of that, but, it’s a relevant point I feel.

    David, what is wrong with fruit juice? If you could point me towards the evidence that fruit juice is a killer? Yes, it’s loaded with fructose which will raise triglycerides, but that’s a good thing according to Ray Peat. And I don’t see any long term fruitarians dropping dead from high triglycerides (30 bananas a day – triglycerides must be through the roof). Yes, fruit juice is processed and man made so perhaps not natural, but, it works for a lot of people on the Ray Peat inspired approach.

    Which brings me to my other point. It’s not a diet. Ray Peat has never, for one second, ever said that his way of eating is a ‘diet’. He refuses to ever define it like that.

    If you can’t make sense of his recommendations, that’s your problem. They are pretty straight forward to me.

    Oh, and who says salmon is healthy? You can’t prove whether any food on the planet is truly good for you or not. Everything is based on opinion, and is relative to that person.

    I don’t eat salmon either, and never felt better in my whole life. I used to eat fish. Go figure.

    He’s not banning you from eating these foods that you have been brought up to believe are Godly. He just recommends a certain approach to things.

    Avoid PUFA, eat a diet that is gut/endotoxin friendly, eat foods to increase thyroid, eat a diet that makes you feel good, etc etc.

  3. Chris,
    I understand this is an old post, you may not respond to the new comments. But I read your other article (probably an interview) and you mentioned about some people have problems with lactic bacterias and you recommended soil-based probiotic in that interview. I think I might be one of those people. I was wondering if I should avoid all lacto-fermented foods. I seemed to have diarrhea (very soft stool) when I consume fermented foods. I’m not sure if I have dysbiosis, but I do want to improve my gut health. Should I only use the soil-based probiotic supplements and avoid fermented foods? How about prebiotic? Which one is better? or should I do both?

    • Quinny, like you I also suffer with diarrhea from eating fermented foods. I never used to! It started when I began taking kefir. Now I can’t even tolerate apple cider vinegar! And think I have SIBO as a result! So much for kefir being a health gut food! I’m so upset! As an avid fermenter I can honestly say that taking kefir has ruined my life! There’s little on the internet about it or how to cure/rectify it though… And no one who promotes fermented / kefir / probiotics seems willing to talk about what to do when it goes wrong. So all I can do for now is avoid all fermented foods and deal with the stomach cramps/pain/diarrhea as and when they now frequently occur. 🙁

  4. Hi Chris,
    Thanks for your postings/articles!
    I wanted to ask you if I am unable to drink fermented drinks now (due to histamine allergy) do you think I will ever be able to? How should I go about building up my tolerance for them?
    I have been taking probitiotics for a long time as well as staying away from dairy, sugar and grains and taking gut healing formulas.

    Thank you!

  5. I made my first batch of fermented beetroot – taken straight out of the garden.After a few days the top half of the beets began to change colour . I put them in the fridge where they’ve sat ever since as I’m not game to eat them.
    The top half of the contents are grey looking . The brine is thick and gluggy but just tastes salty and tangy..The bottom half is still reddish – the colour you’d expect beetroots to look. I’ve combed websites but have never found any mention of the contents changing colour. Does anyone know whether the beetroot is still edible. A friend suggested I hadn’t sufficiently covered them with the brine. I was sure they were covered though only just. Any comments before I ditch them would be welcome.

    • Very, very light cooking will not kill all of the beneficial bacteria; however, it will kill some, and they will not stand up to much heat or prolonged cooking. It is best to consume fermented foods raw.

  6. Chris,

    I am concerned about alcohol content in fermented foods and kombucha. I am a recovering alcoholic, and have read this could “trigger” my addiction, especially the kombucha. I can make/have made my own kombucha but want to be sure if it is safe for me to drink. And, after reading your previous reply re: Beet kvaas, would that be “safe?” And I am assuming the fermentation in things like sauerkraut is ok. Thank you for your time.

  7. Chris,

    What say you about Dr. Ray Peat’s assertion that fermented foods should be avoided due to lactic acid content, and that it’s a burden on the liver to detoxify the lactic acid?

    He says cheese is OK since it’s a very nutrient-dense food to begin with.

    • Mike,
      If we are going to discuss Ray Peat’s ideas, then I think we should start by looking at a concise summary of what his dietary recommendations are. The problem is I have looked extensively on his site, and I can not find any summary of his dietary recommendations. I do find dozens of people around the web trying to explain and cobble together what Ray Peat recommends, each conflicting with the other. This point is truly maddening.
      Secondly, it appears that Ray Peat promotes lots of fruit juice, never eating any salmon, etc. I think we will have to forget about Ray Peat.

    • In short: I don’t agree at all. Almost all healthy traditional cultures consumed fermented foods, and they have numerous health benefits.

  8. I have found there are many way to make sauerkraut: 1. wild, using just the naturally occurring bacteria already on the cabbage, 2. with whey, or 3. using a starter culture. Which method do you feel is the best way?

    • In the traditional foods blogosphere I’m seeing movement away from using whey starter culture for vegetable fermentation, under the theory that the bacteria that digest milk aren’t the same ones that digest vegetable matter, anyway. Even if you use a starter culture, what may be really working is the bacteria already on the cabbage (Most likely).

      Ideas can become entrenched. When I was a sourdough bread baker (hobbyist), a lot of people thought you had to put the sourdough starter by an open window to “catch” the wild yeasts, but studies of sterile vs. normal flour proved that the yeasts were already present in the flour, not from the air. I think it’s much the same for vegetable fermentation. i’ve been just as successful with vegetable ferments with and without starter culture. I do use an airlock to have a little more control over what gets in an out (it’s not perfect anaerobic fermentation, I know that).

      • Thanks, I once heard that fermented vegetables have around 50 mcg K2 per serving, and if specific starter cultures are used they have far more, 500 or more mcg per serving. Do you know if there is any truth to this?

    • Both methods work. I find that the flavor of wild-fermented sauerkraut is superior to sauerkraut made with a starter such as whey. However, it’s important to note that in dairying cultures, whey was traditionally used to aid the fermentation of vegetables and to help cure meats.

  9. A couple questions on fermentation. Also I have Hashimoto’s. I have yet to experiment with making my own yet. So I buy occasionally kombucha in the the store and I drink about 8 ounces a day. When I first started drinking it my face would get flushed every time, now the flushing is intermittent and not every time, any thoughts? Next question does fermented foods cause diarrhea? I do not consume cabbage now, but in the past when I would have sauerkraut it would cause a sudden urge to go to the bathroom. I really want to start fermenting myself to save money and heal my gut. Thanks.

    • In my experience kombucha is one of the least therapeutic ferments and the one most likely to cause adverse effects. I would try beet kvaas as an alternative, or water kefir.

      Fermented foods could potentially trigger diarrhea if you have significant dysbiosis. You have to start with a very small dose and add them in slowly.

  10. I’m a big fan of Jenny’s blog and am tempted by this course. Chris, what do you think about fermented grains as a small part of an overall nutrient dense diet? From what I remember Jenny herself has gluten sensitivity but has experimented and found herself able to tolerate Einkorn wheat but in your opinion is it better to avoid grains altogether or can some long home-fermented grains be an acceptable compromise? For what it’s worth I’ve done a 30-day gluten free trial and reintroduced the odd small piece of sourdough to no appreciable effect (I’ll never make it a staple again) that I can tell although I have some small gut issues remaining – hence my interest in increasing the amount of fermented foods I make beyond my trusty sauerkraut!

    • I don’t consume them myself, because I feel better without them. That said, fermentation can at least partially mitigate many of the disadvantages of grains, and there is evidence of traditional cultures like the Loetschental Swiss and Gaelic of Outer Hebrides that consumed significant amounts of fermented grains and maintained good health. If you have a relatively healthy gut and no significant inflammatory disorders I don’t see a problem with giving them a shot, but I wouldn’t make them a staple.

      • Thanks for the reply, Chris. With a history of eating disorders I struggle with the rigidity of saying I will *never* eat a grain again so to know that if I properly prepare them it is possible to have a small amount is important to me. I also have two children and am keen to strike a balance between teaching them about healthy food and feeding them a nutrient dense diet and not being so strict as to lay the groundwork for food issues for them in the future. This is a difficult task! Both were breastfed for years, have never taken antibiotics, and are rarely sick and my instinct says a little home-made sourdough (I’ve even taken to adding a spoon of rye starter, rich in phytase, to occasional steel-cut oats to mitigate some of the phytic acid in them) is fine – particularly if topped with liver pate or butter and raw milk cheese! I suppose I am more in line with the WAPF diet than paleo in this way, as well as with appreciating the importance of fermented foods in the diet. I hope that as my kids get older they will be able to make good choices for themselves.

  11. is this a good thing to do if a person has sensitivities to mould? As in, if I eat mould affected food, I suffer sinus problems. I also have sensitivities to chemicals but if I avoid chemical exposures then I get better with the foods and don’t have to avoid moulds at all. Even when it rains i get sick, and I have to wear a mask everywhere I go, otherwise I get upper respiratory symptoms (eyes, nose) from fragrances and chemicals. Fermenting foods is attractive to me because of the health benefits but so far, I’ve made my own cream cheese from yogurt and I think must have had mould on it as I’d had it out of the fridge for 24 hours.
    What do you think about this? Are fermented foods safe for people sensitive to chemical and/or moulds?

    • Miche –

      If you are sensitive to mold, you can still enjoy fermented foods (most of them, anyway); however, I would take care to make sure that you are fermenting in an airlocked device like a Harsch crock or a pickl-it which can help to prevent the growth of mold.

  12. I purchased this course a while back and I LOVE it. I still refer back to it and I felt much more comfortable fermenting everything!

  13. What can be done if you get migraines from some fermented foods? Also I was loving raw milk kefir for nearly a year, but then I got chronic diarrhea from it, which lasted almost two months and is just getting better. Since my baby drinks the raw milk fresh in her Weston A Price formula and has no problem, I do not think why I got sick was the raw milk, but from bad bacteria multiplying along with the good in the kefir itself. Not sure about that. Doctors couldn’t find anything. But the more I think about it, I used to have brushes for only cleaning the kefir jar. Eventually I got lazy and used regular kitchen brushes that were used for other things to clean the kefir jar after each batch. This could be a problem you might want to warn people about while making fermented foods. All bacteria can multiply, not just beneficial ones. Being scrupulously clean means special clean scrubbers and brushes, and very hot washing water.

    • Nancy – Althrough I’m sure Chris will have a more precise reply, the likely cause of your headache is either a histamine or FODMAP intolerance. If I were in your shoes, I’d completely avoid the foods that cause the headache and continue to work on your gut health with probiotics, bone broths and avoiding grains. You could try reintroducing them again a little bit at a time after 30 days and see what happens.

      Also, keep in mind that it’s hard for pathogetic bacteria to multiply in any significant amounts along with the good bacteria. Usually one or the other is dominant and keeps the other to a minimum. It’s likely that your kefir was just fine but you may have had some other cross contamination on the outside of the bottle or other surface from the kitchen brushes. But you are correct, good santitary practices in any food preparation are a must!

    • Jen: great response. I don’t have much to add. The most common causes of reactions to fermented foods are indeed histamine or FODMAP intolerance or severe gut dysbiosis.

    • If you experience migraines from fermented foods it could be a histamine issue. Cut down on fermented foods or other histamine heavy foods or try DOA to see if it is a histamine related migraine.