EP18: The wild art of fermentation

Fermented foods are a delicious and rich source of nourishment.

The fermentation process can transform the flavour of food from the plain and mundane into delicious flavours enlivened by colonies of beneficial bacteria and enhanced micronutrients.

In this episode I talk with former plant biochemist Viola Sampson turned “fermentation passionista” on the benefits of wild fermented foods.

Show Notes

About Viola Sampson

Viola Sampson Fermentation Workshops

Having previously worked with bacteria in the lab as a research scientist, Viola now collaborates with bacteria in the kitchen to make sauerkrauts and kimchi.

She is passionate about sharing the delights of naturally probiotic foods and enjoys gathering wild ingredients for ferments.

A complementary therapist, Viola teaches natural healthcare practitioners about the fascinating, invisible world of the human microbiome.

She offers wild fermentation workshops for beginners and more experienced fermenters, in London and nearby.


Robin Harford: Can you just give a bit of an introduction as to how did you get into wild fermentation? What’s this big kind of obsession that you have?

Viola Sampson: Yeah, it is an obsession or a passion. My background was … well, I wanted to be a genetic engineer, actually. So I went to university-

Robin Harford: Sounds ominous.

Viola Sampson: Yeah, absolutely … to study genetic engineering, which meant that I did basically two years of a kind of medical training, which is how you did it in those days, medical biosciences. But because I was interested in plants, and particularly wanted to go into crops, I also studied plant biochemistry and ecology as well throughout that time. So that ended up with me working with bacteria in laboratory settings. So that’s sort of chapter one. Then there’s a sort of long wiggly journey that includes having gut issues after traveling to Southern Africa, and potentially from before then as well, as we might talk about later. And then I studied complementary therapy, studied craniosacral therapy, and the fermentation sort of landed in my lap, really, in terms of looking into gut health, and the gut microbiome, which are the microbial communities in our gut, and discovering that actually we used to eat a lot of fermented foods, like every culture around the world has fermented foods like sauerkraut or kimchi, or there’s miso, to name just a very few. Yogurt, that’s a really obvious one that most people can think of.

Robin Harford: Sour dough, that kind of thing?

Viola Sampson: Sour dough, although that’s more for taste rather than for the probiotics for the health-promoting bacteria. So yeah. And then I basically … as soon as I got interested in that, I discovered someone called Sandor Katz happened to be visiting London, and there happened to be a space on his workshop. I leapt into it. In fact, a friend gave half of it to me for a birthday present, and it’s just been a gift that’s just kept on giving. So yeah.

Robin Harford: That’s really cool, because Sandor was a good friend of my plant mentor, Frank Kirk. They did a double act in America, before fermentation and wild food kind of took off. Frank would get everyone to go out and gather plants from day one, and then on day two, Sandor would take people through the process of fermenting them.

Viola Sampson: Great. Yeah.

Robin Harford: So yeah.

Viola Sampson: They’re real natural buddies, I think, those two practices.

Robin Harford: Very much.

Viola Sampson: Yeah.

Robin Harford: Yeah. Why not just get canned or vinegared? Why not preserve your plants in vinegar? You mentioned probiotics. Why not just go down to [inaudible 00:03:37] and get Yakult or Yokult or whatever that horrible bloody-

Viola Sampson: Don’t get me started on that.

Robin Harford: … [crosstalk 00:03:44] sugar and … Yeah. Cool.

Viola Sampson: Yeah. This is the way we used to preserve our food, up until very recently, so only a couple of generations ago. It might be that your parents or your grandparents didn’t have a fridge. The fridge was invented not that long ago. What we used to do, would be preserve our vegetables in salt, and the salt creates the environment for something called lactic acid bacteria. So they’re bacteria that produce lactic acid, and that increases the acidity of the ferment. That works very much like vinegar. Vinegar is actually acetic acid. So we’re preserving our food for right through the winter, sometimes for years. For example, I think in Hungary you wouldn’t want to eat a sauerkraut that was less than four years old, perhaps. You know?

Robin Harford: Wow. Okay.

Viola Sampson: That’s probably at the far end. I’m sure there are lots of Hungarians who eat sauerkraut at six weeks old, but who knows? So yeah. And what’s really wonderful, particularly in this part of the world, in the temperate world, we get a glut of vegetables through the summer and into the autumn, and then we can preserve them through the winter using lacto-fermentation.

Viola Sampson: And then tin canning was another way that recently … relatively recently in terms of human history, that preserved food. And then so we’ve got tin canning. We’ve got refrigeration, and also vinegar pickling. Once you could make vinegar commercially, and most vinegar that you can buy at down at Tesco’s or wherever is actually just made in a laboratory now, not the kind of old-fashioned way.

Robin Harford: Wow, without the mother.

Viola Sampson: Yeah.

Robin Harford: Wow. Okay.

Viola Sampson: So it’s just acetic acid. Yuck. Yeah.

Robin Harford: Does that include the white wine vinegars and all that as well?

Viola Sampson: No. No.

Robin Harford: Okay.

Viola Sampson: It’ll be like the pickle and vinegars-

Robin Harford: [crosstalk 00:06:03] vinegar, and yeah.

Viola Sampson: … the white, yeah, yeah. I mean, yeah. I’m saying that without going down to Tesco’s and reading up on exactly where they get their malt vinegar. Yeah. And that was a very quick way. Instead of waiting for the bacteria to do all the work producing the lactic acid, you could just quickly make acetic acid, pour it on the vegetables, and you’ve kind of basically got, in theory, the same thing. Now what we’re seeing, are people coming up with all kinds of health conditions, asthma, obesity, even mental health issues are now being linked to changes in our gut microbiomes, so changes in the ecology of the microbial communities living there. So for me, it’s really common sense that a food that we used to eat a lot of perhaps every day, we don’t eat at all now, and our gut health is really in decline. It’s not the only reason that it is in decline, but for me it makes absolute common sense to reintroduce these back into our diet. People really do report health benefits from it.
Viola Sampson: One example was me. I didn’t have a cold at all last year. It’s very rare for me to go through an entire winter without cold or flu, and eating this, my immune system has just been really boosted.

Robin Harford: So they’re good for your immunity?

Viola Sampson: Absolutely. Yeah. Yeah.

Robin Harford: Wow. Okay. What kind of ferments are there? I mean, sauerkraut is the one that I normally say to people when I’m doing [crosstalk 00:07:42] you can ferment … I don’t go too much into the fermentation side, but when people would kind of look at me quizzically, I say, “Well, you know sauerkraut?” “Oh yeah, I know sauerkraut.” “Right, okay, well that’s a lacto-ferment or a lactic acid ferment.” Well, what other ones? I mean, they’ve got kimchi in Korea and … Any …

Viola Sampson: Show me something I can’t ferment, actually. But that’s me, and a few other fermenting passionistas. So yeah, kimchi. What we think of as kimchi in the West, is napa cabbage, which we call Chinese leaf. Big chili paste. A basic kimchi recipe would be daikon radish. Fish sauce. Pack it all into a jar. Spring onions. Usually something like that as well. In the UK and in the West, that is considered kimchi, but actually there are a gazillion different kimchis. There are as many kimchis as there are Korean people making them. They can, like I say, ferment all the things. You can end up with anything in there.

Robin Harford: Okay, because I always thought kimchi was maybe more root-based, whereas sauerkraut is more leaf-based. Is that … No?

Viola Sampson: Yeah, I don’t know that that’s …

Robin Harford: That’s not true?

Viola Sampson: Well, it’s not something I’ve come across.

Robin Harford: Okay.

Viola Sampson: Yeah.

Robin Harford: Okay.

Viola Sampson: Both sauerkraut and kimchi have the same basic method, which is dry salting, which we can go through here. But in terms of what you put in them, it’s really up to your own … well, your creativity is the only thing that’ll hold you back, really, because you can try different flavors, and they may well turn out in lots of different ways that you couldn’t even imagine. So definitely worth experimenting. In terms of other lacto-ferments, yogurt is a lacto-ferment. So if you look on the side of a yogurt pot, you’ll probably see lactobacillus acidophilus there, lactic acid bacteria. It’s the acid that curdles the milk and thickens the yogurt, and also preserves it.

Robin Harford: Okay. Are there ways to create ferments without salting?

Viola Sampson: You can. You can choose not to use salt. It’s a little bit harder, in that the salt favors the environment that lactic acid bacteria prefer. Fermentation is transformation by bacteria. It’s transformation of a food by bacteria. Rotting is transformation of food by bacteria. Now, what makes the difference between our rotting leftover mashed potato and our sauerkraut, is the fact that it’s lactic acid bacteria doing the transformation. Lactic acid bacteria like salt. Other bacteria don’t like salt. So it is absolutely possible to ferment … make sauerkraut that’s salt-free, it’s just you may have a few that don’t work out quite so well, and you have to tend it a little bit carefully to make sure it doesn’t get mold. But yeah.

Robin Harford: How would you do … Well, are you going to take us through the basic principle of making a sauerkraut?

Viola Sampson: Yeah, which we can do now.

Robin Harford: Yeah, yeah. Sure. Okay.

Viola Sampson: Yeah.

Robin Harford: Let’s find …

Viola Sampson: I thought it’d be really nice for your listeners to have some chopping, because it’s one of my favorite sounds, actually.

Robin Harford: Yeah, sure. We’ll have to see how it works out.

Viola Sampson: So yeah. Yeah, let’s see if the mic picks it up.

Robin Harford: Take one.

Viola Sampson: Okay. First of all, I should say I don’t follow recipes.

Robin Harford: Right. Okay.

Viola Sampson: So I will talk through as clearly as what I can in what I’m going to be doing here right now.

Robin Harford: But I will say, just to interrupt you, that Fiona’s put over a PDF handout, which we can give to people who listen to this podcast episode, under the Resources section on the podcast page, which they’ll find at eatweeds.co.uk. Just click the podcast link, and you’ll get to it.

Viola Sampson: Great. Yeah. So yeah. I mean, I’m a bit of a bucket chemist or a intuitive cook, because when I was a biochemist, I had to pipette things at one microliter, which is 1/5000 of a teaspoonful of liquid.

Robin Harford: Right. Okay. All right. Yeah, we don’t want to scare people. We’re not getting into pipetting.

Viola Sampson: I’m not into any kind of measurements at all, as you discovered. I’ve got here a white cabbage, and I’ve got a red cabbage, because actually I want to make something that’s pink because I like colors.

Robin Harford: So color’s important for you? You don’t just want to have this kind of green, mushy look?

Viola Sampson: Sometimes I go for the green, mushy look. But for this one, I don’t know, I quite like a bit of pink on my plate. And I’ve also got a quince, which is a windfall from this little park at the end of my street. So I don’t know if that’s technically foraging or scrumping or just picking up a quince on my way to work.

Robin Harford: Gathering.

Viola Sampson: Gathering.

Robin Harford: I’m really trying to get away from thing, “Oh, I’m a forager.” I’m actually a gatherer, because you have hunter-gatherers, you know?

Viola Sampson: Well, I certainly gathered this.

Robin Harford: It’s like, we don’t have hunter-foragers, do we?

Viola Sampson: I was well chuffed. Yeah. So yeah, I’m going to chop of the bruised bits of the quince.

Robin Harford: Have you done quince before?

Viola Sampson: I have. Yeah. I’ve got the end of a quince sauerkraut at home, which is now … it’s almost a year old.

Robin Harford: Okay.

Viola Sampson: I’ve been eking it out because it’s really, really delicious.

Robin Harford: So basically, anyone who’s got gluts of fruit or vegetables and you don’t want to compost it and you recognize there’s still food there, this is a perfect way to preserve it?

Viola Sampson: It’s a great way to-

Robin Harford: Without poisoning yourself potentially with botulism, which is what canning can do.

Viola Sampson: Yep.

Robin Harford: I remember Sandor was saying that he doesn’t know anyone in any culture that’s ever been poisoned by a lactic acid ferment or wild ferment.

Viola Sampson: It’s true, actually, that there’s more food poisoning incidents from raw vegetables, salads. So actually, you could say it’s actually safer to eat a lacto-fermented vegetable.

Robin Harford: Wow, okay. Would you sit down and have a whole meal of wild ferments? Are they relishes? They’re more relishes, rather than …

Viola Sampson: Yeah. I eat a lot. I would say to anyone, you should start off small, especially if you are someone who has gut issues, because it’s an ecology you’re talking about. You wouldn’t sort of … well, you might completely rip up your garden and plant a whole load of different things in there, but if you’re really working with your garden, you introduce things slowly and see where their favorite habitat is. So it’s very much the same, I’d say, gardening and microbiome.

Viola Sampson: I’m chopping up the cabbage. I’m chopping it small so there’s a lot of surface area for the bacteria to feast, which is basically what they’re doing. They eat the sugars and the other goodness in the vegetables, and they produce lactic acid as their waste product, actually. And then as they produce the lactic acid, the …

Robin Harford: That’s going into a bowl now.

Viola Sampson: That’s going into a bowl. That’s what that sound was. As they produce the lactic acid, the acidity of the ferment increases, and the bacteria that like less acidic environments start to die off, and a new set of bacteria grow in. So there’s different phases, according to the acidity of the ferment.

Robin Harford: Because I experimented with ferments using whey instead of just salt, which actually was really, really interesting in the sense that in order to get the whey, you kind of just go out and buy it. I had to make this kind of ricotta cheese, so this cream cheese, and the byproduct of that is whey. And it was like, “Oh, right. Okay.” I realized that I’ve been going down to shops buying cheese, and I’ve totally missed out this whole blooming cycle that cheesemaking goes through. So whereas the whey normally is given to pigs or whatever, I mean, we can actually use it to preserve our foods as well.

Viola Sampson: Yeah. Well, I’m not a massive fan of using whey in ferments.

Robin Harford: Okay.

Viola Sampson: I mean, it’s a great way to use up what’s actually kind of a waste product, actually, of cheesemaking. But what you do, is you skip the stages of fermentation, so you’re going right in. You’re not going getting that natural succession of species.

Robin Harford: Oh, really? Oh, okay.

Viola Sampson: What we’re doing here, is something called wild fermentation. Whey is a starter. You’re putting bacterial species in there. The bacteria we’re using here are soil bacteria, that are found in the cabbage. And yeah, so then there’s this, like I said, a kind of natural succession. What I encourage people to do is actually when they make it, is taste, not only to get to know your ferment really well, but keep tasting at different stages, because there’s different bacteria at each stage.

Robin Harford: How long would you normally leave a ferment before it’s kind of really mature? I mean, would you start eating it 24 hours later? Because it’s still quite salty, isn’t it?

Viola Sampson: You can do. Kimchi is traditionally eaten within the first 10 days.

Robin Harford: Really?

Viola Sampson: Yeah.

Robin Harford: Oh, wow. Okay.

Viola Sampson: First couple of weeks.

Robin Harford: Okay.

Viola Sampson: And like I said, sauerkraut four years. I always say, “Eat it when you want it and when you like the taste.” It gets softer the longer you leave it, and it gets more acidic, so you get a real … People prefer their sauerkrauts or their kimchis at a different age. I like to think that you go for the one that you need the most.

Robin Harford: Yeah. I think that I like the [inaudible 00:19:05] side of it. It’s like, forget the calendar and the diary. Eat it when it’s appealing.

Viola Sampson: Yeah. I would say also, I mean, there are loads of different really great things like pickle pipes and the all kind of pickling paraphernalia that you can put on the top of your jar, that lets the gasses out, but doesn’t let the air get into your ferment. That prevents mold growth. But I think just doing it really simply with a normal jar is … you know, because you keep opening, you keep tasting it. That’s my favorite way of doing it.

Robin Harford: What kind of temperatures are you keeping it in? Are you keeping it in the fridge? Are you keeping it just on your kitchen top?

Viola Sampson: Just on my kitchen side. Somewhere not too warm, not too cold. I mean, I don’t have a thermometer or anything. I tend to just keep it away from direct sunlight. But I’m not particularly precious about it. I literally just stick it anywhere I’ve got space, because they do take up a lot of space. In terms of the fridge, well fridge is a fermentation slowing device, right? You put your ferment in the fridge when it’s as crunchy or as soft and it’s the taste that you like it, so that might be any time between a few weeks to a few months. And then what it does, is it slows down the fermentation. It doesn’t stop it altogether, so it will carry on fermenting slowly. So yeah. So there are times that you might want to put it in the fridge.

Viola Sampson: So I have a bowlful of a very pretty mix of red and white cabbage shredded. I’m going to grate a bit of this lovely quince as well. The last time I did this, I chopped the quince up into little bits, but actually it stayed really sort of chewy for a long time, and the cabbage got nice and soft. So this time, I’m grating it. So it’s a constant learning process.

Robin Harford: Okay. So we’ve got grated quince.

Viola Sampson: Mm-hmm (affirmative).

Robin Harford: Red cabbage, white cabbage, just sliced up.

Viola Sampson: Yeah.

Robin Harford: Nothing too fine, not big chunks. Like you said, you want the surface area. What are we doing now? We’ve got salt.

Viola Sampson: We’ve got salt. This is the …

Robin Harford: So not just any old salt? You can’t just use [Saxa 00:21:57] salt?

Viola Sampson: You can actually use any old salt.

Robin Harford: Or iodized salt?

Viola Sampson: It will work.

Robin Harford: Really? Oh, okay.

Viola Sampson: Yeah, it will work. The iodized salt tends to discolor the vegetables. It may reduce some of the bacteria as well. Normally use iodine to sterilize things. But it does work, so it doesn’t kill them off altogether. But I go for sea salt. Usually I go for a nice gray sea salt, because the gray indicates that it’s full of minerals. Another really great thing about lacto-ferments, is that they are … the digestion of the bacteria make the minerals and nutrients more bioavailable to us, so we can absorb them more easily. So you get some added nutrition, depending on the color of the salt that you use. A lot of people like to use pink salt, rock salt-

Robin Harford: Yeah, people say there’s this pink salt stuff [crosstalk 00:22:55]-

Viola Sampson: Himalayan salt.
Robin Harford: Himalayan. If you’re in India, sorry, I’ve just come back. People go, “Himalayas,” [inaudible 00:23:05] “No, it’s Himalaya, actually.”

Viola Sampson: Is it really?

Robin Harford: Yeah, it’s what the Indians, it’s how they pronounce it.

Viola Sampson: Oh, is that right?

Robin Harford: Yeah, yeah.

Viola Sampson: Okay, well Himalayan salt. I don’t like using that because it’s mined.

Robin Harford: Really?

Viola Sampson: Yeah, well it’s rock salt, isn’t it? It comes out of Himalayas.

Robin Harford: Oh, god. Yeah, of course.

Viola Sampson: Big holes in the Earth. Big holes in the Himalayas.

Robin Harford: Wow. Okay. That’s a good point.

Viola Sampson: So yeah. Sea salt is … well, it’s essentially renewable, isn’t it? So I always go for the gray sea salts, or slightly whiter ones. So yeah. This is my bag of sea salt. Again, sorry folks, we’ve not got measurements here. I’m going to do it by taste. What I’m going to do is sprinkle on a pinch, a healthy pinch. We’re going to be massaging it into the cabbage.

Robin Harford: That’s a real squeezing between your hands and fingers.

Viola Sampson: Yeah.

Robin Harford: As though you were wringing out a cloth, almost.

Viola Sampson: Yeah. You can see already, you can see that’s getting really juicy [inaudible 00:24:15].

Robin Harford: For people who are listening, I mean, the amount of salt is really … just start with a little bit. A little bit obviously is not really quantifiable, but use your brains, yeah. It’s kind of common sense stuff. Just quarter of a teaspoon [inaudible 00:24:33] in a bowl that’s got about 500 grams, 700 grams of cabbage, and just keep working it. You know you’ve got the right amount of salt when …

Viola Sampson: Well, I aim for … It’s really personal taste.

Robin Harford: When liquid starts coming out.

Viola Sampson: Well, it’s done to taste, actually.

Robin Harford: Oh, right. Okay.

Viola Sampson: Like I say, some people prefer not to have salt at all, and that might be because they’ve got a medical condition, or they just don’t like the taste of salt. After I’ve done a bit of massaging … Yeah, the salt does pull out the juices, so it does make this bit a lot easier. In fact, you could just salt it and leave it for a few hours, and you don’t have to do quite so much massaging. So I’m going to taste … Apologies to anyone who’s got that thing where they can’t bear to hear people crunching. I’m going to go for a bit more salt. I like to aim for the saltiness of olives. So it’s sort of yummy salty.

Robin Harford: Right.

Viola Sampson: So I’m going to go for another good pinch.

Robin Harford: Saltiness of olives. That’s a good way of explaining it. I like using as little salt myself. I mean, some people used to kind of quiz me in a kind of confrontational way about, “Yes, but it’s salt, and salt’s really bad for us.” And then someone who was a fermenter said, “Well actually, the salt is for the ferment. It’s not for the human.” Which I don’t know whether that’s true. It [inaudible 00:26:19]. So you’re just really mashing it.
Viola Sampson: So you can start seeing now, I’m picking up and squeezing it.

Robin Harford: Oh, yeah. Right. Yeah, yeah, yeah.

Viola Sampson: And you can see … like you said earlier, like wringing out a cloth, you can start seeing the juices coming out as I squeeze into the bowl. Let’s just have another taste of that. I reckon that-

Robin Harford: Don’t offer me any. [crosstalk 00:26:53]-

Viola Sampson: … fits. Would you like to-

Robin Harford: … without permission.

Viola Sampson: What do you reckon?

Robin Harford: Mmm.

Viola Sampson: You can taste the quince as well, right? It’s really nice, isn’t it?

Robin Harford: Nice.

Viola Sampson: Now we get our jar, and I think clip top jars are the best, but you can use any jar. This is about 500 mls. I tend to use, if we were going for measurements, I think 750 or a liter jar is a good one to start with. I’m going to start packing it in here, and starting off with a little bit, and squeezing it down into the bottom of the jar. What you’ll see, is the juices starting to rise up. What you’re aiming for, is a jar where the veggie is really pushed and packed down in, and a little layer of juices over the top. If you haven’t quite managed to make enough juice, you can add a little filtered or bottled water. Don’t use chlorinated water because chlorine is there to kill the bacteria.

Robin Harford: You know, I just use my tap water.

Viola Sampson: Do you, and it works fine?

Robin Harford: It works absolutely fine. Now, I am in Devon, so we have hard water run soft, so that may make a difference. But yeah, I don’t normally bother.

Viola Sampson: Right.

Robin Harford: Which I know is heresy-

Viola Sampson: Yeah, it’s probably just me being a bit precious.

Robin Harford: … to the healthies out there.

Viola Sampson: I’m just pouring in the last of that juice.

Robin Harford: And you can pound down … I mean, I occasionally use a rolling pin, wood rolling pin, just to kind of [crosstalk 00:28:40]-

Viola Sampson: Squish it down further.

Robin Harford: … and just squish it down a little bit further.

Viola Sampson: Yeah. The reason you’re wanting a layer of liquid, and you want your layer of liquid to be there really throughout the time that you’ve got your ferment bubbling away on the side, is because the lactic acid production is what’s called an anaerobic process. It happens in the absence of oxygen. So you need to make sure that your vegetables are covered with the liquid.

Robin Harford: You know, I’ve just drunk a glass of this London water. I wouldn’t make my ferment with London water. That is disgusting tasting water. What is it, 18 … it’s like urine processed 18 times.

Viola Sampson: Yeah. Homeopathic sewage. Yeah.

Robin Harford: Oh my god. He says, pouring himself another glass, just because I’m really thirsty.

Viola Sampson: It was all that salt you just ate on the chopped-up vegetables. So yeah. Now, it’s just about you put a lid on it. The reason I say clip top jars, is because they’ve got this rubber seal around. In the early stages of fermentation, say the first sort of 10 days, depending on whether it’s a hot environment or a cold environment, about the first 10 days, you get a bacteria … it’s a bacteria called leuconostoc mesenteroides. The name is perhaps irrelevant, apart from the fact I really like it. They produce carbon dioxide, as well as the acid. The carbon dioxide starts bubbling up through the vegetables. If you have a lid that’s on here that’s screwed on tightly, you have a glass bomb basically, and many a bottle in a jar has exploded in a fermenter’s household.

Viola Sampson: So I like to use the clip top jars because they got this little rubber seal, and you can just … the rubber seal will blow if it gets highly pressurized, but you can also just let the pressure out. You know, they’ve got that little tag on the side, [crosstalk 00:30:52] knew what they were for, you just pull that, and it just goes …

Robin Harford: They call it burping, don’t they?

Viola Sampson: Yeah.

Robin Harford: Burping your ferments.

Viola Sampson: Yep.

Robin Harford: Yeah.

Viola Sampson: Yeah.

Robin Harford: It’s quite a cute phrase, I think.

Viola Sampson: It is. Yeah.

Robin Harford: Slightly rude.

Viola Sampson: Yeah.

Robin Harford: If you’re British.

Viola Sampson: So burp your ferment daily, is my recommendation, certainly if you’re not using a jar with a rubber seal. And then you just taste and watch and enjoy.

Robin Harford: Okay, so you do actually … you do clip it [crosstalk 00:31:24]? Okay.

Viola Sampson: I clip it. Yeah. I’ve tested it now by mistake, and the rubber seal does blow if you forget to burp.

Robin Harford: Great. Okay. Because I was under this impression that … because the way I’ve done it, is I would get to this stage of having my salted vegetables in the Kilner jar. I would leave the top off, and all I would do is just put a Ziploc bag with water, and just keep it in the top. I’d keep it like that for a week for the ferment to get going, and then I would clip it shut.

Viola Sampson: Okay, great. That is one way of doing it. I don’t like plastics anywhere near my ferment, so I don’t use them.

Robin Harford: Or boiled stone or something like that could be used.

Viola Sampson: A boiled stone is great. I actually use really heavy glass nightlight holders. So as long as you don’t have coloured glass, because you don’t know what the toxins are in the colour, and you don’t have antique glass that could have lead in it-

Robin Harford: Lead in it, yeah.

Viola Sampson: … then you’re safe with pretty much any glass.

Robin Harford: Okay.

Viola Sampson: But yeah, boiled pebbles is another one. The reason you have that is that weighs the vegetables down so they stay underneath the liquid. Another thing you can do is literally just get a spoon every day, and just press the vegetables down. Because what you don’t want, is the vegetables floating on the surface and getting mould growing on them because they can become a little island that mould can grow on. So that’s the reason why you need to keep it submerged.

Robin Harford: And if you do get mould? Do you have to throw it all out?

Viola Sampson: That is really a personal decision. I’m someone who will scoop stuff off. Sandor Katz is someone who scoops stuff off. Other people wouldn’t do that. They prefer to throw it away.

Robin Harford: Yeah, I would encourage people just to scoop.

Viola Sampson: Yeah.

Robin Harford: I mean, I made some brined red peppers the other day with my four-year-old granddaughter. She did all the work. And then I stuck them on the shelf in our bathroom, and I went away, and I’d forgotten. I came back, and there was this hair monster coming out of the jar. I just literally took like a little cap-

Viola Sampson: And it just came away?

Robin Harford: … and just pulled it out, and it just came off when I took out the one bit of pepper that had gone all funky, and they’re fine. They’re absolutely fine. I mean, why throw that away? You know.

Viola Sampson: Well, there are people who would argue that the mould, its little roots, the [mycorrhizae 00:33:55] are so small that you can’t see them, and they can go right through the ferment, all the spores can.

Robin Harford: Okay. [crosstalk 00:34:02].

Viola Sampson: So I think it is a personal decision. But if you’re quite happy scooping a bit of mould off the top of a jam, then you’re going to be someone who’s quite happy scooping a bit of mould off the top of a ferment. To be honest, if you’d been waiting for a ferment for several weeks or months, the last thing you want to do is throw it all away. But you know-

Robin Harford: And the smell as well, isn’t it?

Viola Sampson: Yeah, smell.

Robin Harford: I think if it smells and it’s appealing, keep it. If you’re suddenly wanting to retch, then, you know.

Viola Sampson: It depends how far it’s gone down. I would always scoop off a good layer as well, so yeah. So that’s a very quick tutorial, isn’t it?

Robin Harford: So that’s then just left for as long as you want, really?

Viola Sampson: Yeah. [crosstalk 00:34:45] Keep tasting, and enjoy when you’ve got it. Ferments don’t last that long in my house, because they’re too yummy.

Robin Harford: Yeah. Just to recap, you chopped up some cabbage, not too really, really fine, but not big chunks either, just as you would normally chop a cabbage for a salad. You added salt to taste, not salt by quantity, but salt to taste. You crushed it between your hands and fingers, like wringing out a cloth, until the juice started coming out of the vegetables. Then you packed it into a Kilner jar. You pressed it down. You got a layer of liquid just above the vegetables. And that’s it.

Viola Sampson: Yeah, and you just make sure you keep checking, keep checking nothing’s floating.

Robin Harford: Yeah, and just keep it submerged under that liquid because that’s … well, if it’s under liquid, it’s not going to rot, and not going to grow hairies.

Viola Sampson: All the mould spores and the yeast spores are going to be coming from the air, so the less contact there is with the air, the better. So yeah, keep your lid on it, and keep burping it for at least the first couple of weeks I would, I think. And then the carbon dioxide slows down. The carbon dioxide production slows down, and you’ll see the bubbling sort of gradually stops.

Robin Harford: Yeah. Thanks for doing that. It’s been really good. It’d be great to see how these sound effects come out [crosstalk 00:36:15] chopping the cabbage and [inaudible 00:36:17] quince, and mashing vegetables [crosstalk 00:36:20] your hands.

Viola Sampson: What I’m really passionate about in this stuff, is that we’re working with soil bacteria here. This is just one further example of how our health, our human health, is intimately linked to the health of the soil, the health of our environment, and the land that our vegetables come from. I always use organic vegetables for that reason, because organic farming tends to take care of the soil in the way that industrial farming doesn’t. I think another reason that we’re getting so many health problems that are now being linked to the health of our microbiome, is because of things like industrial farming damaging the soil. It’s because there’s such a great distance from farm to plate. People aren’t living on the land anymore. People aren’t getting soil under their fingernails and in their mouths. So yeah, so introducing these foods is one way to support our health, but then so is taking care of the land. Yeah.

Robin Harford: You were talking about the cesarean birthing and how the developing fetus needs actually to have certain types of bacteria, but in our modern way of living, those often are not part of the developmental process of the wee diddy human when it’s forming.

Viola Sampson: Yeah. That’s another way it really kind of links into our obsession with sterilization. Thanks to wonderful developments in surgery, basically there’s this misconception that healthy bodies and healthy environments are bacteria-free. We now know that’s really not the case. Birth is a really good example of this, and other sorts of standard medical practices where you’re quick to use antibiotics and get rid of the good bacteria. We’re now seeing how important those bacteria are. The womb until very very recently was thought to be a sterile place. We now know that the placenta has a unique ecosystem, the unique microbial community there that they think actually starts in the mother’s mouth.

Robin Harford: Wow.

Viola Sampson: Amazingly, the bacteria travel through the mother’s body and set up home in the placenta. Incredible, mind-blowing stuff. And also the umbilical cord. Researchers have been analyzing umbilical cord and the developing baby’s gut, and the baby is born with bacteria already inside. What also happens in a natural birth, the baby comes out through the birth canal, and it is great. We’re born head-first and facing our mother’s anus. We get a gobful of bacteria on the way out. That bacteria, they’re lactic acid bacteria. Again, lactic acid bacteria live in the vagina. They keep the environment acidic there, which prevents other infection. Just like it prevents mould growth on our ferments, it helps keep our bodies healthy. And those lactic acid bacteria in the baby’s gut ready to digest the first milk, first breast milk ideally. Again, the bacteria in breast tissue that then populate the baby’s gut as well.

Robin Harford: Which boosts the immunity.

Viola Sampson: Which boosts the immunity again. So yeah. It’s called seeding the microbiome, which is a lovely phrase. A cesarean baby doesn’t come out through the birth canal, obviously. Their guts are populated actually by the bacteria in the environment of the hospital … Now, we know what the bacteria in the hospital are … and then hopefully the parents’ skin, the bedding of the hospital. There are a lot of autoimmune issues, things like asthma, that are much, much more prevalent for cesarean babies, and ongoing gut issues. I attribute a lot of my gut issues that brought me into lacto-fermentation to being a cesarean baby. So you that bit sort of a tougher start in life. And then, of course, I was a very outdoorsy kid. [inaudible 00:41:06] handfuls of soil in my mouth, and stuff like that. So that really helped over the time, but definitely getting that first mouthful. And there are medical trials now of taking a swab of the mother’s birth canal, mother’s vagina, and putting that in the mouth of the cesarean baby. It really does rectify the gut … Yeah.

Robin Harford: Wow. It’s funny because I came back from India a month ago. I had a big discussion with the Ayurvedic doctors and the Tibetan doctors there. They were saying the importance of eating with your hands, because over here in the West we have knives and forks and it’s considered a little bit weird if you start at a dinner party tucking in with your hands, and actually really the importance of the bacteria on your hands to keep you healthy, which is why in India they eat with their hands. So it’s anywhere where we can introduce bacteria, pick that potato off the table with your hands, and pop it in irrespective of the disapproving looks from whoever, parents often, do it, because any way that we can introduce healthy bacteria … like you say, seeding the biome-

Viola Sampson: Seeding the microbiome. Yeah.

Robin Harford: … seeding the microbiome is good, and can only …

Viola Sampson: I mean, yeah. There are sensible precautions to take around … but, yeah, it’s that sterility.

Robin Harford: Yeah, the toilet bowl, basically.

Viola Sampson: Yeah, although there are more bacteria on a mobile phone than there is on a toilet seat.

Robin Harford: Really?

Viola Sampson: Yep.

Robin Harford: Wow.

Viola Sampson: That makes you think, doesn’t it-

Robin Harford: Yeah, it does.

Viola Sampson: … in terms of what’s healthy, what’s unhealthy, and a healthy environment isn’t necessarily bacteria-free. And then of course, actually I think more important than anything, is getting out of your home. The things like antibacterial handwashes and all the other horrendous chemicals that I know you don’t have in your home, because yeah, it’s destroying our health in lots of different ways.

Robin Harford: Great. If people want to get in touch with you because you do run wild fermentation workshops-

Viola Sampson: I do.

Robin Harford: … up here in London, don’t you?

Viola Sampson: Yeah, London and nearby. Yeah.

Robin Harford: Okay. So the South East, basically.

Viola Sampson: Yeah.

Robin Harford: Where do they get hold of you?

Viola Sampson: They can go to my website, which is violasampson.com.

Robin Harford: Okay.

Viola Sampson: There will be a link there that will take you through to the wild fermentation workshops. I also teach complementary therapists about the microbiome, so the bacteria that are essential to health, bacteria and viruses and yeasts and other fungi. So yeah, the link is off that page.

Robin Harford: Okay, great. And like I said earlier, where this podcast episode is on my website, there is links to Viola’s website, and also to the PDF handout that will basically talk you through more of different funky ways of playing with funky ferments. Thanks a lot, Viola.

Viola Sampson: Great. Thanks very much.


  1. This is brilliant! I’d never really thought about the origin of Himalayan salt before, I’ll be spreading the word. I’ve been making sauerkraut for a while, and had mixed results until I started using 2 grams of salt per 100 grams of vegetables, and it’s been consistently successful since then. I used to do it by taste but I think some days I just like things to taste more salty than other days!

  2. It is really revealing!! Managed to put together into a whole bits and pieces of traditional practices. The reason and the necessity of them!! I may share that in Greece where I come from, making olives or pickles I put into the jar a thin layer of olive oil (on top) to prevent mould to the floating pieces. I hope that doesn’t interfere with the fermentation. It is a traditional practice though.
    Thank you so much fot this.

  3. Great podcast. Thanks. I teach fermenting classes myself in Somerset and I’m wondering if anyone can tell me what happens to the nutrients in seaweed when you ferment it in a mixed ‘kraut with cabbage, say. Tim Spectre in his book The Diet Myth says we have to have a gene to digest seaweed and unless we’re from a culture that eats it like the Japanese or perhaps some of the Welsh then seaweed goes straight through us. I wonder if fermenting the seaweed has the effect of making the nutrients more bio-available to people without the seaweed digesting gene? I’m making sauerkrauts with seaweed because they taste great.

    • Katie – What Tim Spectre says is “We don’t yet know how long it would take or how many buckets of seaweed for the average unexposed European to acquire the crucial marine microbes, although a few Welsh and Irish living on the coast may have them already.”

      The science is still out on this one, as the research papers, he references also state (which I have and have read). By using seaweeds regularly, we can only increase our microbes. But there is a massive amount of research behind the scenes going on around seaweeds and human health. And I mean huge. Spectre is only one voice. It’s not quite so cut and dry. I cover the health benefits in-depth in my online multimedia course The Seaweed Notebook, and I fully reference the science.

  4. Thanks for this podcast guys! I really enjoyed it and learned a lot! I have a question though – is is always necessary to cut the vegetable up and massage in the salt? For example, if I want to ferment chillies, can i leave them whole and just put them in a brine solution?

    • Yes, you can Frank – but you might need to try different brine solutions from 2%-5%. E.g. red peppers need a higher brine solution as they develop mould easily in weaker solutions. Dependent on where you are and your local climate.

  5. Hey Robin,

    Great podcast – I didn’t listen to it mind you, but I did read the full transcript 🙂

    I commented on your article on the uses of bramble inquiring about the fermentation of different leaves – you’d said you were working on an article on that topic. Not to be pushy 😉 but am very much looking forward to reading it!

    I’ve been struck with an inspiration to experiment with fermenting ‘weeds’ this evening. I’m about to go out and harvest some dandelion, plantain, lambs-quarters, nettle and anything else I can find and play around with some different combinations.

    A quick but sincere thank you for what you do and for the information you share with everyone here.

    All the Best,

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