What even is lacto-fermentation?

pickling is the act of preserving food with acid you can do that as simply as submerging the food in vinegar or lime juice for a real long time as long as you get the pH below the magic number of 4.6 you're going to have pickles but some people would argue that those are not true pickles no no no they would say that true pickles are preserved by an acid created by the bacteria inside the food itself lactic acid that's what lacto fermentation is it's a pretty magical process that yields some of the most delicious foods humans have ever come up with it was one of the only ways people had to preserve vegetables until refrigeration and when it comes to us modern people there are scientists who believe we would be healthier our guts would be healthier if we ate more of these lacto-fermented Foods again even though we don't really have to anymore because you know we have the fridge that said it can be a little scary eating a wet thing that you just left at room temperature for a few weeks how do you pickle safely and how big are the risks well field trip to the University of Georgia extension where food microbiologist Dr Carla Schwann directs the national Center for home food preservation when you look at the microflora the indigenous Flora in a cucumber for example or you know cabbage if you're doing sauerkraut there is around 10 million cells of indigenous bacteria that are not lactic acid bacteria so E coli coliforms cholesteria yeah you heard that right lots of bad bugs inside vegetables usually not enough to make a healthy person sick which is why we can eat raw vegetables though with these cucumbers you got to make sure to knock off those little trichomes very very sharp of those are and for pickling cucumbers you want to cut off the flower end not the stem end but the end where the flower used to be why Always remove the flower end because you can have certain fungi that are present and they have enzymes that basically break down pectin plus the flour itself makes some of these enzymes that could make the pickles kind of soft and slimy so that's not good that's why we cut off the flower end there's not a ton of bad bacteria in most veggies but what matters is the proportion you got millions of bad bacteria in contrast to maybe just a thousand or a few thousand of the good bacteria that we want lactate acid producing bacteria there's only a few of them relative to the bad ones so we've got to give them an advantage we select the good bacteria and we suppress the the bad bacteria that are present there so how do we do that we utilize salt the trick is how much salt if you completely pack food in salt you will kill everything salt draws the water out of cells bacteria shrivel up and die you preserve the food basically forever which people have been doing for thousands of years that may be how some of them accidentally invented lacto fermentation maybe somebody was trying to Salt cure their food but they didn't have quite enough salt that day and they did not put on enough salt to kill all microorganisms it was just enough salt to kill the bad ones lactic acid producing bacteria are able to tolerate some salt how depends on the species but here's one example some lactic acid bacteria are able to absorb compounds from their environment that balance out the osmotic pressure of the salt water around them like the amino acid Proline for example they suck it into their cytoplasm it doesn't hurt them in there the way that salt wood and yet it is able to balance out the osmotic pressure of the salt that's outside of the cell it's like two people leaning on the same swinging door from both sides the door stays shut and the water doesn't leak out of the cell so the sweet spot where bad bacteria die and good bacteria Thrive is between two and two and a half percent salt by weight for pickled cabbage that's really easy to figure you just weigh out your cut cabbage figure out what 2.5 percent of that is and sprinkle on that much sodium chloride it's the weight of the salt not the weight of sodium specifically in the case of European style pickled cabbage sauerkraut this is basically it you let the Cabbage sit for a while maybe mash it up a little to draw out the natural water inside the Cabbage I love sauerkraut and kimchi but at this stage it really does smell like farts you know what smells nicer body wash from native sponsor of this video look at these gorgeous scents I'm posh special to Citrus and herbal musk but today I'ma try sea salt and Cedar smells like the beach minus the rotting seaweed note of course check that luxurious and foamy lather despite the fact that native body wash is sulfate free my skin feels great with this stuff it's also phthalate free dye free vegan and cruelty free and I appreciate that the scents are subtle and tasteful whether you want to smell like spicy and woodsy or like clean and crisp native has options for you for the fall check out the cabin collection cozy scents like warm cider and cinnamon and remember native mix deodorant and toothpaste too I use native deodorant every day in the plastic free container three body washes are normally 27 but if you use my link and code regusia 5 you'll get them for 17 that's 40 off with my link and code in the description limited time offer thank you native anyway cabbage is really easy to ferment because enough water comes out of the Cabbage when you salt it that you can keep everything submerged below the salt water the brine which you have to do you have to create an anaerobic environment for the food if it's exposed to air you're going to get some bad bugs especially fungi on the other hand you cannot seal this up tight either I know this looks and feels like we are canning but we are not canning canning is a totally different thing that requires using heat to sterilize everything among other steps and you can't really do that with fermentation because you'd kill the bacteria that you need to ferment your food and make lactic acid canning also requires totally airtight seals but we can't do that in fermentation either no no yeah you're not going to seal in the Mason jar because you have production off CO2 and that could potentially explode so you don't want that right so some people do ferment pickles in just a loose fitting mason jar to let the gas Escape but Dr Schwann says that's not really a best practice like here's my Kraut after it's been fermenting about six weeks and you can see the dry cavities that have developed fungus and other bad stuff could grow in there where there's air so what you really want is a weight that will push all of the solids down below the brine as they shrivel there are pickling weights you can buy they're usually ceramic which is both heavy and chemically non-reactive I should have done that this Crouch smells great but it's probably a little risky I don't think I'm gonna eat it let's do better with the Cucumbers whole cucumbers are a little bit trickier to pickle because not enough water is going to come out of them to keep everything submerged so you're gonna have to use some water add some water to get enough Brine and you have to factor that water into your calculations we need the total contents of this pot to be between two and two and a half percent salt by weight not just the water so I either need to weigh the cucumbers with the water and then figure out 2.5 percent of that or I can just follow a Time tested volume based recipe like the ones provided by Dr Schwan's National Center for home food preservation they have a book that you can buy but they have tons of recipes for free on their website tested and trusted by scientists I'm following their recipe for dill pickles fine sea salt it dissolves readily and it has no additives like iodine or anti-caking agents that could Cloud the Brine and then this is weird a little bit of vinegar I thought the whole point of lacto pickles was no vinegar well Dr Schwann says that like commercial dill pickle makers usually use a lot more salt maybe up to five percent salt that's a little bit more reliable there's definitely no way that any bad bugs could survive an environment that salty the problem is that the pickles are then like inedibly salty so what they do after they ferment them is they put them into pure fresh water to purge the salt out of them we're probably not going to do that at home so for us that little bit of vinegar is just an insurance policy it controls the bad bugs before the lactic acid bacteria can get established and start making their own acid dill pickles have Dill duh maybe some spice and then a whole lot of garlic that's what makes a New York Jewish deli style pickle to me some people use food grade lime it gets you crispy pickles but people say that tannins in black tea leaves have a similar effect no idea if that's actually true lay in the Cucumbers they really can't be any bigger than that or they'll take too long to pickle and you can see that they're floating we need to wave them down with something to keep them in that anaerobic environment metal would react with the acid glass is chemically inert and it'll provide a window through which we can watch into the basement closet with you normal room temperature is generally the best for lacto fermentation and we'll see you in a few weeks time lapse in the first week or so enzymes break down the chlorophyll anyone can see that but a trained eye like Dr Schwans sees something else those small bubbles I don't know if you can see here could be gas escaping from inside the Cucumber cells but it could also be CO2 which might be created by our first string good bacteria low kind of stock messengeroids yeah what she said that species or a similar one will dominate for the first week making CO2 and lactic acid when that is happening you also see let's say you have coliforms present you also see the coliforms dying coliforms would be bad things like E coli bad soil bacteria those first good ones can only handle a little acid so once the environment gets to like one percent lactic acid they shut down and some more acid tolerant species take over like lactobacillus brevis and lactobacillus plantarum they go about eating the sugar in the Cucumbers yes there's a little bit of sugar in a cucumber they create lactic acid as a waste product eventually driving the pH in there below 4.6 which is crucial you might be wondering why Dr Schwann is plotting a downward trajectory to describe Rising acid concentration it's because as acid goes up pH goes down and we got to get that pH below 4.6 closer to do matulina will not grow below 4.6 and so if your pH is above 4.6 you have to be worried about clostridium and you know that clusterian botulin produces a neurotoxin that causes botulism I would definitely other one to have that there's also other pathogens that will survive and will grow at higher pH so you're talking about listeria talk about E coli salmonella so it's it's a whole gang of bacteria um that could be a present if you stop the fermentation too early that said for many years New York Jewish delis have sold these things they call half sours which is a pickle they take out before it's completed its fermentation process so it's not so sour and it's a little bit more crisp and green and nobody's gotten botulism from those as far as I can tell no case reports that I can find crucially though those delis put them into the refrigerator and refrigerator would also slow the growth of the botulism bacteria that's really really important back in the day they didn't have refrigeration so they had to keep fermenting until the pickles are really sour somewhere between a pH of three and four is where the good bacteria can't take it anymore they shut down and your pickles are done as they're ever going to be they should smell sour they should taste sour at this point it's safest to either can them or transfer them to the fridge because bad things could happen wait for it wait for it and mold giant mold Bloom about six weeks in spores could have floated in on the air or they could have been on my spices mold or other fungus can grow on any of the surface that's exposed to air you're supposed to skim it off as soon as you see it but I didn't want to mess up the time lapse and as a result things got really out of hand now lots of the fungal growth is going to be harmless things like yeast and Dr Schwann says even dangerous fungi generally will not create mycotoxins in salty conditions but only if you skim frequently you don't want to have that you know different layers of mold because that top layer of mold could be producing mycotoxin and you know it's not in contact with the brine or anything and yeah I would not eat that if you had to remove it over time consistently then yes um but like this after eight weeks definitely not yeah I'm just gonna have a teeny tiny little bite tastes great what a shame here's what Dr Schwann likes to use as a weight a sealed plastic bag full of 2.5 percent brine it conforms to the Bowl fully covering the surface though gas can still get out and if the bag leaks no problem because it's filled with Brine and not plain water that would dilute the brine if you do that and you follow a time-tested recipe like the ones they have from the national Center for home food preservation that's going to keep you out of trouble Dr Schwann is aware of no documented case in which someone has gotten sick from properly lacto-fermented vegetables meat sure but not vegetables and I've been combing the literature I can't find anything I've talked to other food microbiologists they don't know of any cases it's just not a thing that seems to happen these pickles are really safe as long as you do everything basically right use your senses though if the pickles smell like they're rotting if they don't smell or taste sour well that's an indication that your good bacteria lost the battle against the bad ones but follow the recipe and that just probably won't happen what's more likely to happen is that all of these live beneficial bacteria and their metabolites will end up in your gut where they will improve your gut health and that's a really complicated topic that we'll talk about more another day but that is real science there has been some studies showing that I think if you consume 120 grams of kimchi I think it was the study I saw a day you're going to have health benefits and I was trying to do that for a while and it's a lot of kimchi I wasn't able to keep up but yeah in South Korea that's the average and of course kimchi is basically sauerkraut with a lot more interesting flavors delicious but it's all thanks to those lactic acid bacteria that have co-evolved with us humans for Millennia and long may we mutually benefit each other

Channel: Adam Ragusea

Views: 1,136,468

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Id: 7UdquGa6jBs

Length: 14min 58sec (898 seconds)

Published: Mon Oct 17 2022