THE MICROBIOME SUMMIT : Love Your Microbiome
The Art of Food Fermentation
Sandor Katz
Sandor Katz
Sandor Katz (also known as Sandor Kraut) is an internationally recognized expert on fermentation. Mr. Katz has an enthusiasm for fermentation that is contagious. He has written several books that have helped to demystify fermentation – and make people feel less afraid of trying this technique at home. By fermenting at home, you can harness the power of microorganisms to make food more delicious, more stable for storage, and more digestible. In this interview, Mr. Katz will explain how easy it is to ferment fruits and vegetables and will inspire you to get started.
- Tracey:
- So we are here today with Sandor Katz, otherwise known as Sandorkraut. Thanks for joining us here today Sandor.
- Sandor:
- It’s my pleasure to be with you today. Thank you.
- Tracey:
- You have written some very wonderful books. The last one that I read, the Art of Fermentation, that’s the one I want to talk about with you. And you have this beautiful foreword from Michael Pollan. And he explains in his foreword to your book, your book is more than a book about how to ferment. He heralds you as a demystifier of the fermented food world. He further praises you and says you are able to explain the visible world of fungi, bacteria, the community in which we live and the industrial food system that is undermining the health of our bodies and the land. Speaks volumes. Please explain to us what does the art of fermentation mean to you?
- Sandor:
- Well I mean, I guess I would back it up one step and say, what is fermentation? Broadly speaking, fermentation is the transformative action of microorganisms in our food. But what we now understand, thanks to the science of microbiology is that all of the plants and all of the animal products that make up our food are populated by elaborate communities of microorganisms. On the one hand we can observe, on food that sits around for a while, the microorganisms decomposing it or making it rot or spoil. But then as a practical matter, in culinary traditions in really every part of the world, people without understanding about microorganisms but through their powers of observation and trial and error, figured out how to harness the power of microorganisms to make food more delicious, more stable for storage, more digestible. And so, rather than decomposing, we use this power that is part of all of our food in order to enhance our food in different ways. This practice is used in every part of the world, in every culinary tradition that I have been able to learn anything about. Almost every individual in almost every part of the world eats and drinks products of fermentation every day. In some parts of the world most food that people eat is fermented. And worldwide, the statistic that I have seen is that about one third of all food that human beings put into our mouths has been transformed by the actions of microorganisms first. So this is a very significant transformation of our food. And I would go so far as to say, agriculture would not be possible without people having an ability to preserve food from seasons of plenty to get them through seasons of relative scarcity. In fermentation has just been such an essential part of how people have figured out how to do that. We forget that with our refrigerators, and our freezers, and our preservative chemicals that are found in food nowadays, historically fermentation has been one of the major ways that we have had to preserve food. So it is a really important phenomenon that, because we have all been brainwashed to be so terrified of bacteria many people approach the foods themselves or certainly the process of undertaking fermentation, transforming the foods in their own kitchens with a great deal of fear and trepidation. Because the question becomes, how can I be sure that I have good bacteria growing in my fermenting sauerkraut and not some dangerous bacteria that might make somebody sick or even kill someone? So in general, people are thinking about fermentation from a place of fear and anxiety when in fact fermentation is and always has been a practice that is all about safety and extending the useful life of food.
- Tracey:
- Absolutely. I think there is a lot of fear out there. I think for one thing people don’t feel comfortable with the idea that microbes are actually useful to us. Like is there anything that I should worry about and so you demystifying the fermented food world is really important. So I’m just going to lay it out there. Is there anything possibly that anyone can get sick from when they do fermented food?
- Sandor:
- Let’s break it down. It’s not like all fermented foods are the same. Let me give you the statistics for fermenting vegetables. In the realm of fermenting raw vegetables: sauerkraut, kimchi, pickles, things of this order. These foods exist in every form from beverages to sauerkraut. But in the realm of fermented vegetables, according to the US Department of Agriculture there is no case history; they cannot find one single case history of food poisoning or illness from fermented vegetables. So this food is about as safe as food gets. I mean we hear every year about people getting sick from raw vegetables because clearly there is the possibility of contamination. Usually it’s manure from a factory farm uphill washing over a field of vegetables. It could just as well be sloppy handling, somebody who failed to wash their hands at one of those critical moments. But the point is, if you ferment them, if you create a situation where the lactic acid bacteria are going to dominate which is very, very, very easy to do. You chop the vegetables, you lightly salt them, squeeze them or pound them to get them a little bit juicy and then stuff them into a jar submerged under their own juices. Every single time the lactic acid bacteria dominate. They create lactic acid and to whatever extent there might be salmonella bacteria hanging out or E. coli bacteria or something that might make you sick, they can’t survive the acidity. And as the acidity develops, they are destroyed. So really in most cases fermentation is a strategy for safety. Now in the case of a salami, actually just has to do with the inherently greater dangers of meat than of vegetables. Not to scare anyone away from salami, I mean you definitely can make salami safely it just takes a really clear understanding of the parameters for safety. And so there’s a little bit more education that you need in order to do that safely. But in the realm of fermented vegetables, literally in five minutes you could learn everything that you need in order to do it effectively and safely. And that’s where I recommend that people begin fermentation practice. Then if you want to get involved in fermenting fish, fermenting meat, fermenting milk, I mean there are all kinds of incredibly wonderful ways that people do this. But start off in the realm of raw vegetables and fruit because there’s just no known potential for danger. The relevant bacteria generally are present on that food that you are fermenting in the first place. It is very elegant that way.
- Tracey:
- I love the idea that our vegetables have their own ecosystem. And their own bacteria. That we are just trying to grow and liberate and make more useful for our bodies.
- Sandor:
- Sure. And I think also just understanding the direct connection that the bacteria that we need in order to be healthy come from the soil. And so the way that we can access them is through plants that we eat. I would say that the whole perspective on bacteria, from a scientific perspective has really evolved in our lifetime. I would say that for any of us that grew up in the United States in the 20th century, we grew up in the hysteria of the war on bacteria and this idea that bacteria are bad, bacteria should be avoided and when they are encountered, bacteria should be destroyed by any means necessary. Certainly biology is coming to a more nuanced understanding that bacteria really are the matrix of all life. In evolutionary biology there is a broad consensus that all life is descended from bacteria. And the corollary to this that doesn’t get talked about as much is that no form of life has ever lived without bacteria. So just as each human being is host to something around 1 trillion bacteria that give us a lot of our functionality, our ability to effectively digest food and assimilate nutrients. Most of what we would describe as our immune system. We are learning that the bacteria in our intestines actually help to regulate our brain chemistry, serotonin and other compounds like that. Our bacteria sort of regulate aspects of our liver function, our circulation, almost every system of our bodies really. And the same is true of a cabbage or a carrot or a cow or a grape. And it’s just; this is just one reality of life is that all multicellular forms of life have bacteria that they are host to, that give them some of their functionality. Or give us some of our functionality. What we now understand is that all of the plants that we eat carry with them these elaborate communities of microorganisms. The amazing thing is that for thousands of years, without specifically knowing of the existence of the organisms, people have been working with them. Just through our powers of observation and trial and error. So I would say it’s a very exciting time in fermentation where we are understanding for the first time ever, the mechanisms of it. It has always been regarded as sort of like a mystical and mysterious realm of human experience. Because one of the products of it is alcohol, which has its own mystical qualities, people have just recognized fermentation as a mysterious and magical force in their lives. In all kinds of surviving indigenous cultures, there is a laboratory ritual organized around fermentation and some of the major world religions there are still elaborate rituals organized around fermentation so I would say that, long before science began to recognize the importance of this phenomenon cultures around the world recognized its sacredness and its importance.
- Tracey:
- Yes. I love your passion for the microbes.
- Sandor:
- Well you know, they are an important life force on this planet and I think that it’s very empowering to tap into it instead of being afraid of it learn to work with it. And also harness some of that power. Because in our context of exposure to chemicals designed to kill bacteria, people in general having much less diverse diets than people in the past have had. Many people are suffering with digestive problems from basically lack of supportive effective bacteria and we need probiotics, we need bacteria that can help to restore biodiversity in our gut and help improve digestion, improve immune function, improve mental health. All of these different aspects of our health. Food can be medicine and the living bacteria that are still part of many fermented foods, fermented foods that haven’t been cooked or heat processed after their fermentation can be very therapeutic. I just hear anecdotal stories from people all the time and I have my own stories about healing these foods can be.
- Tracey:
- Absolutely. Can you speak to some of the benefits you personally have experienced since you started fermenting foods?
- Sandor:
- While that’s a little bit hard for me because I have never not eaten these foods. I grew up in a family where we were eating these foods a decade before I started making these foods, I started learning about some of the healing benefits of them so really seeking them out more than they already had been in my life. One of the reasons I was seeking this out is that I was dealing with my own health crisis. I have been dealing with HIV for 25 years and trying to do things to keep myself healthy. And I wish I could tell you that the whole story was fermented foods kept me healthy but I had a terrible health crisis some years back. And I have been on meds every day for 17 years. But the one thing I will say is that everyone I have ever met who takes the kind of meds I take has digestive problems associated with them. Which I have never ever experienced. So that affirms once again, well maybe these foods, can’t solve every problem you could conceivably have, sometimes you need to pursue different kinds of treatments but even as a complementary treatment I would say that fermented foods have my digestion going really well. As well is my overall immune function. So I don’t know, this is a limitation of people’s individual experiences yielding information. So I don’t know. And one of the unfortunate things is that there has been very little rigorous study, clinical trials, of actual fermented foods. There is a huge body of work looking at probiotic capsules. Because most probiotic capsules are filled with strands of bacteria that are proprietary, that somebody owns. And so they have a good incentive to invest money in a trial that’s going to sort of demonstrate the efficacy of their probiotic capsule. But nobody owns sauerkraut. Nobody in particular stands to gain by demonstrating that. There has just been much less research. The most interesting research that I have found looking at actual fermented foods was a study that was done in Spain. And what they did is recruited volunteers who liked to eat a variety of fermented foods. I think the criteria was at least five servings a week of at least three different kinds of fermented foods. Including olives, including cheeses, including salamis, including yogurt. And what they did is, they did baseline blood work looking at various quantifiable indicators of immune function. And then they put everybody on a deprivation diet where they couldn’t eat these fermented foods and beverages. And what they found is that after several weeks of deprivation everybody’s numbers on these immune indicators went down. And then they let people eat yogurt. So half the group was on traditional yogurt and half the group was on new fangled, improved, probiotic yogurt. In both groups regained approximately equal levels but nobody return to the levels they started with until they were allowed to resume a diet of diverse fermented products. Like to me the lesson is, that in the realm of bacterial stimulation of immune function, it’s all about diversity and biodiversity, and cultivating biodiversity in our intestines. And that’s why there’s no single bacteria that is the answer. It is the sort of bio diverse foods. And that’s what traditional fermented foods have over capsules, I would say is biodiversity. Because each probiotic capsule has billions of copies of one bacteria or maybe two or three bacteria. But the traditional fermented foods are literally these embodiments of biodiversity. Each one actually has uncountable different bacteria in them. And these sort of broad communities of shifting composition as the ferment develops and the environmental conditions shift in terms of pH and such.
- Tracey:
- For sure. It is sometimes confusing when you walk into the supermarket and you are like, okay I’m not quite ready to ferment my own foods but I want to buy some fermented foods. What should people be looking for? I mean is the sauerkraut that is in where the pickles that have been sitting on the shelf for six months, is that the fermented food you are talking about or is it something different?
- Sandor:
- So focusing on sauerkraut and pickles. If the sauerkraut is in a can and sitting on a shelf, anything in a can has been heat processed. That’s what canning is like a form of heat processing to sterilize food and then seal it in a vessel. That sauerkraut was certainly fermented with the bacteria from the cabbage in the first place. But then it was subjected to high heat in order to enable it to be in the can. I mean if it was alive it would be producing carbon dioxide and the can would be kind of bloating and nobody would ever want to eat it. If you are looking for live sauerkraut, I would say first of all seek out local kraut makers. In any large, medium, or small city you will find some kind of a local kraut maker and maybe you will have to go to the farmers market, maybe you will have to go to some like local health food store, maybe you’ll find it in the whole foods, maybe you will find it in a local supermarket, I don’t know. But the place you will find it in those stores is the refrigerator. Because a living product, once you seal it in a jar is going to produce pressure if it’s in a warm ambient environment. So as a practical matter you really need to keep it in the refrigerator once it’s in a jar. And generally the people that are selling a live product are going to be telling you that on the label. It will say somewhere, live, raw, unpasteurized. Some set of those words. Maybe the word probiotic. I mean it’s hard being a consumer, if you’re looking for good quality live culture fermented foods, you have to really read labels and understand what you are buying. And also just let people know, it’s easy, easy, easy to make your own fermented vegetables. I mean sometimes people see the live fermented vegetables in the store and they are like, they look at the jar, and they are like, why should I pay nine dollars for a jar of vegetables? Well it’s expensive to take up space while it’s fermenting and then have to keep it refrigerated. And these are just intrinsically expensive products. But if you just buy a head of cabbage yourself, bring it home; spend 10 minutes shredding it, chopping it up. Lightly salt it there is no magic number, I always tell people to just salt it to taste. The salt begins to pull juice out of the vegetables then if you get in there and squeeze what you are doing is you are bruising the vegetables, breaking down cell walls, helping it to release juices. After a couple of minutes the vegetables are nice and juicy. If you squeeze a handful it is like a wet sponge and juice drips out. Once it’s wet like that, just stuff it in your vessel. A jar is the easiest thing to use. Like a wide mouth jar, something like this. A litre sized jar will take about a kilo of vegetables to fill up. You can use a 500 mL jar, will take about a half kilo, about a pound of vegetables. So you don’t need a lot, you can mix different vegetables together. But it’s a really rewarding practice and sometimes people with busy lives assume they don’t have time for it. But my perspective as a person with a busy life is that, if you invest 15 minutes doing this and let it ferment for a week then all those quick meals when you are like throwing a piece of cheese on a piece of bread, you have something that’s actually, really healthy that you can put onto it. And make it a more substantial, more nutritious meal. My perspective really has become it enables you to enhance those fast meals on the run. So it’s even more important to have things like this around in your kitchen if you feel like you are super busy and always eating on the run.
- Tracey:
- Absolutely. Now when we are picking our jar, we don’t have to sterilize it, we don’t have to do anything. We just have to start shoving the vegetables in.
- Sandor:
- Yeah, you want to work with a clean jar; soap and water are perfectly adequate for this. I mean nothing else is sterile, your vegetables aren’t sterile, your hands aren’t sterile, your knife isn’t sterile. And even, the idea of sterilizing a jar is a little bit of a fantasy in your house. There is all kinds of chemicals you could use to briefly sterilize it and then you are going to rinse it with nonsterile water and put it in your nonsterile drying rack with your nonsterile air blowing around. Sterility is largely a fantasy that has been sold to us by people who want to sell us chemicals.
- Tracey:
- What are some of the yummiest fermented foods that you have made in your book? That we should flip to and should try and make those ones?
- Sandor:
- I would say that most of the greatest delicacies in the world are products of fermentation. If you walk into a gourmet food store anywhere and look around and ponder the nature of the foods you are looking at. They are fermented. Cheese is fermented, cured meats are fermented, all the condiments we put on our food are either directly fermented or based on vinegar, which is a product of fermentation. Coffee is fermented, chocolate is fermented, vanilla is fermented. Certain kinds of tea are fermented. So you know, all the good stuff is fermented and anything anybody could make cured meats and cheeses if they really wanted to. You have to create, kind of special temperature and humidity conditions for effective aging so it’s not necessarily easy to do. I would say fermenting vegetables is very straightforward. Kombucha, and there is a whole world of other kinds of lightly fermented soft drinks which are out there. I mean some of my favourites are what I would call fruit kvass, where you take fruit and make a sugar solution and pour the sugar solution over the fruit. And let the fruit spontaneously ferment the sugar water as the flavour of the fruit is infusing into it. So that’s a really straightforward, easy one. All kinds of lovely lightly fermented beverages like ginger beer, the other day I met these young people who had a turmeric soda that they had made with basically raw turmeric in a sugar water solution. So in this realm of likely fermented beverages there is just a universe of possibilities. Kombucha is the one that is most known, so Kombucha is sort of the hook to talk about it but Kombucha is just the tip of the iceberg and there is a whole world of really interesting, really easy lightly fermented beverages that you can make for yourself at home. I love to make yogurt. I have this heirloom yogurt culture that I have been working with for years. And I love my ritual of making yogurt. I have gone through periods of making kefir, that’s another really easy one. But my books are just all about empowering people. So really if you want to make a salami, you could make a salami. You’re going to have to rig up a little chamber for curing it and I talked about ways of doing that. Most other things are much more straightforward. I have been making sake lately that I have been loving. I visited Japan this past winter and the sake brewer who is doing it really old world ways just described to me a really easy way of doing it. And I came home and I tried it and I posted it on my website which is wildfermentation.com. So you can find a really easy Sake recipe there.
- Tracey:
- Thank you so much for sharing your passion and allowing us to feel so empowered to ferment.
- Sandor:
- While it’s my pleasure, thank you so much for having me on.
- Tracey:
- Yes, thanks Sandor.
