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0:17
MICHAEL BRENNER: We're delighted to have Jody Adams from Rialto here-- who we should clap-- with her assistant, Katherine.
0:27
And Jody and Katherine are going to talk in a minute, but first you have to listen to me for five minutes. So Jody and Katherine are going to talk about fermentation. But first, let me just give you a very brief science background. So the question is, what do all of these foods have in common?
0:44
So all of them have been produced with the help of bugs. So you might not like bugs. You might think bugs are disgusting, but without bugs, you would have none of the food to Jody is going to talk about today, and you would have none of the foods on the last slide. So here are some pictures of bugs, just so it's clear what we're talking about. So bugs, lactic acid, bacteria, baker's yeast. This is aspergillus oryzae, which is another bug.
1:08
And these bugs are the things that make your food taste good. I think that's one of the themes of tonight's lecture. So bugs are used for three different things. For preservation. They're very important for preservation. They're very important for flavor intensification. And they're also important for intoxication. And the way that works is very important. So these are bugs, and what they do is they eat things. It's just like us. Sugars, proteins, lipids, and alcohol. They eat them.
1:36
And then what they do is they convert them into other things. Acids, ethanol gas, flavors, aromas. So bugs turn big molecules into little molecules. And in doing that, the little molecules are the things both taste good, and oftentimes bugs do this because they're basically warfare agents to kill other bugs. So for example, Brewer's yeast, which is the thing that makes alcohol, the yeast basically converts sugar into alcohol. And it does that because bacteria, it turns out,
2:07
don't like to live in alcohol. So we actually have a homework problem that we gave our class this week-- which we won't make you solve, but which is a fun homework problem-- which is, suppose you take grape juice, which has a certain concentration of sugar in it. Please calculate the alcohol concentration in the ensuing wine after the fermentation reaction is done. You can calculate it because it's just converting sugar into ethanol. So here's cheese. Does everybody like cheese?
2:31
Does everybody eat the rind cheese? So does anybody know what the rind is? So the rind is what's called a biofilm. So this is bacterial sludge.
2:44
There's a scientist that works across the street, named Rachel Dutton, who did the following amazing experiment. She went and got cheese from all over the world, and she took this biofilm and she took DNA sequences of the microbes that were in the biofilm to discover what was in there. That's Rachel. And that's Ben, who works with Rachel. And they're holding cheese. What they discovered-- I'm going to show you a plot, which is much too busy, but it's an amazing plot anyway.
3:11
So this is a plot of colors, and every one of these columns is a different cheese. And the different colors correspond to different species of bacteria. Or microbes, actually. They could be fungi. So the amazing thing is that every kind of cheese has its own mixture of bugs. It's not just one bug. It's a lot of different bugs. And the tastes that are made come from all the bugs. And good luck. You can't go to the store and order the bugs. That's the whole problem.
3:34
So if you want to make the cheese, you have to find the right place where they happen to have that kind of bug. This is my simple way of thinking about it. And then you need to leave it there. If you're lucky, it'll make the cheese. And it's just amazing. I mean, who knew you were eating all these bugs? OK, so now the other point I want to make, and then I'll shut up, is that it turns out that in cooking-- if you think about where else to bugs
3:54
appear in food, the other place they appear is when things rot. And cooking is actually not so far from rotting. So I have to end with an equation. So OK here you go. So why are there so many bugs? So here's the reason. Imagine we're talking about people. So everybody knows that what happens to one person is that every person divides and makes two people. And then of course, the older person dies off. And then the second people die. And then they make four people.
4:20
And then they die and then they make eight people. And that's how life goes, right? I mean, there are minor variations around that. But that's basically what happens. So if you count the number of people as a function of the number of generations, then there's this wonderful formula. The number of people at time t is 2 to the n, where n is the generation number. Where n is just the time that's elapsed, divided by the time for every generation. And that's our equation. So you all have to clap.
4:47
And the thing is, this equation explains a lot about everything that you're going to hear, and about everything that I just said, for the following reason. Actually, forget that slide. So here's the thing. So we divide. Humans divide, I don't know, every 30 years. Something like that. I mean on average. I don't know what the number is at the moment. So it turns out that salmonella divides every 20 minutes. That's pretty much the fastest a cell can divide.
5:11
Salmonella, E. coli, It's about 20 minutes. So in 12 hours, that's 720 minutes. So that corresponds to 720 divided by 20 generations. And so that corresponds to 10 to the 10 bugs. 12 hours. If you have a cookie on the counter, one salmonella. Come back. 10 to 10 bugs. So then you worry. Do you have to worry about this? So it turns out that every bug weighs about 10 to the minus 10 grams. So this is about 7 grams of bugs. That's a lot of bugs. And that's only after 12 hours.
5:43
So if you wait 24 hours, it turns out you have 10 to the 21 bugs. Just keep going. And that corresponds to 10 to the 11 grams of bugs, which is the weight of about a large number of cars. So with that, I would like to turn it over to Jody and Katherine. JODY ADAMS: Thank you.
6:07
Well, it's always been my dream to teach a class at Harvard. Not really. But anyway.
6:15
I come from an academic family and, I ended up as a cook. So coming back to academia is an interesting route. But I'm thrilled to be here, and I hope that we entertain you and give you some good information and teach you a few recipes. I'm going to start with fermentation is your friend. I think that we have, certainly in the past 20 years, become really nervous about foods that have microbes associated with them. Because we think that we can actually separate the two, which of course we can't.
6:57
Fermented food, for us as chefs, there's this scary thing that happened when we were told that cured hams from Italy weren't going to be allowed to come here. Unpasteurized cheese wasn't going to be able to come to this country, because they were so terrified of microbes. And we know that microbes are our friends, and that fermentation is our friend. It's a lot more than rotting food. From a chef's perspective, fermentation is all about flavor.
7:27
My early memories of fermentation are traveling in Europe when I was in my early 20s, and going to every market, living in youth hostels, and carrying around bags of fruit. And I was determined to try as many things as I could. I didn't know I was going to become a chef, but I was certainly interested in food. And I'd get back to the youth hostel and it was August and they would be bubbling. And they were fermenting. And I'd throw them away. Fast forward to one of the early holidays my husband
8:03
and I, when we were first married, we didn't have a lot of money. We decided we would make something. By that time I was a cook, and we would make apple butter for everybody. We bought really expensive Calvados. We spent hours making this apple butter. We had little labels made with everybody's-- not only their name, but a caricature of them on these labels. And we bottled the apple butter. And we got calls a week later from everybody saying, it's alive! So it was fermenting.
8:38
So they threw it away. But anyway, what I know about fermentation now is that fermentation is flavor. The reason that it's important for a chef is that we are in the business of creating a Proustian experience, and that is flavor plus emotion. Because flavor plus emotion is going to give you a memory. Emotion, for us, is hospitality. That's what we do in restaurants. To make you feel like you're the most important person in the universe and we love you and you're part of our community.
9:19
And flavor is what we strive for, in delicious food with balanced flavors that will help create a good memory. So the memories for us equal repeat customers. Repeat customers equal dollars. And those dollars allow me to go back to Italy and find more flavors. So flavor is really, really important. And what's interesting for me about fermentation starts with flavor. And then when I was asked to teach this, as I started reading about it and reading about the science and the other benefits
9:55
to fermentation-- I mean, we all know there's the buzz going around about probiotics in our internal flora, and all kinds of interesting things that people are doing to try and reverse the sterilization of our internal flora. So as Mike was saying, in fermentation, there are actors which are the good microbes. I mean, they could be good or bad, but we're going to focus on the good ones. There's an action, which is their consumption of carbohydrates, for the most part.
10:29
And the outcome for them is energy. They have to eat. And they eat to reproduce. To become that 10 to the bazillionth number. But for us, what's beneficial is the acid. The alcohol, and carbon dioxide and other things, which are flavor and texture, preservation, and then third, health benefits. And so we start with flavor. The next thing that's important to us the chefs is preservation, because we can hold things. And the last is health.
11:08
And the other thing in there is, of course, that Michael pointed out, was alcohol but I was focused on food. I have a little bit of history.
11:19
It's a brief outline, but it was the things that struck me as being interesting. Of course, we know fermentation has been around since the beginning of time. It was first recorded 7,000 to 6,000 BCE in Neolithic China, both in fermented rice as an alcoholic beverage, but also in milk. It was in 1837 that yeast was identified. In 1840, that bacteria was identified. And not long after that Louis Pasteur connected yeast and alcohol fermentation, believing that the yeast was
11:54
a vital force that caused fermentation. That it wasn't something that was happening in the food itself, but there was this vital force.
12:04
And then a couple years later, he showed that bacteria soured milk. And of course, we know about pasteurization, and it was named after him, and all that. But there was another guy named Eduard Buchner, who separated the enzymatic part of the yeast and identified that as the catalyst. So it wasn't the yeast as a whole but that but the enzyme as a catalyst. And is that the zymose? Does anybody know? Zymaze? No? No. Good. Well, Pasteur is known as the first zymologist,
12:37
but I couldn't figure out what that meant. and then Edward Buchner won the Nobel Prize for his work on fermentation. Yogurt, of course, fermented milk. Been around forever. Been around all over Europe. But it was first brought to this country in 1910 as a health food, and for digestion. In 1920s, there was prohibition of fermented beverages. Now you think about that. I mean, it's going to happen. It's been happening since the beginning of time.
13:12
To try and prohibit that just seems, at this point, crazy. In 1948, the first antibacterial soap was introduced. It was Dial. In the 1950s, antibacterial soaps started to be used in hospitals. And then in the '90s, there was the antibacterial craze domestically in households, which to me was a really scary time. And I think that we're shifting that wave a little bit. And for sure, in my world, fermentation is back. I was asked by a young guy last year at some food event
13:55
whether or not I had a fermentation program at Rialto. I hadn't actually heard of a fermentation program. I didn't know that was something I was supposed to have. But it is what young chefs are really interested in. Of all of the trendy paths that they can go down, I think that this is one that is really compelling. Really interesting scientifically. Really interesting in terms of the role it can play environmentally, and also in terms of internal health, as well.
14:27
Both internal and external health of our bodies.
14:32
So fermentation is anaerobic, for the most part. It's the metabolism or the digestive process of microorganisms. Yeast and bacteria are the ones that we're going to focus on. Yeast actually starts with an aerobic fermentation, and then shifts. But we're going to ignore the oxygen in that. Why do they do it? As I said before, they do it for energy. They do it to eat. How? They find carbohydrates, gobble them up, and excrete alcohol, acids, and gases. So their excretions are what we like.
15:08
And for us, again, it's flavor in beer, pickles, yogurt, bread, cheese, prosciutto. Who are the microbes? Yeast is a single-cell fungus. Bacteria a single-cell microbe. And from what I understand, and I'm not a scientist, the lactobacilli hangs out with bread, yogurt, and pickles. Or in vegetable fermentation. And those are the three things I'm going to show you today. Fermentation in bread. Fermentation in milk and yogurt. And fermentation in pickles.
15:47
So some fermented foods that you know. Yogurt, cheese, preserved lemons. Garum, which is a fermented fish sauce. Prosciutto, dry sausages, bread, cultured butter, wine, beer, hard cider, sauerkraut, kimchi, pickles, kombucha, coffee, chocolate, olives, miso. And then two of the most disgusting fermented foods ever. I've had both of them. And one of them is hakarl, which is Icelandic fermented shark.
16:25
It's a particular kind of shark, and it has a very high uric acid and another bacteria on it that has to be squelched. And so it's buried in sand. And it just kind of rots there for 6 to 12 weeks, and ferments. It drains out the fluids, and that is hung and dried. Has anybody ever had this? It's harsh.
16:52
It really is. It smells like rotting food. It's really ammoniated and not terribly pleasant to eat. But if you're presented with it, you absolutely have to eat it. If you don't, you're a wimp. You would only have it, I think, in Iceland or a Nordic country like that. And it would be insulting for you not to. So if you go on, particularly, if you go on a trip with a group of people who are visiting a country like Iceland and you're
17:22
being toured around, for sure you're going to be asked to try this. So just be prepared. But it's followed up with an aquavit that has a licoricey kind of flavor to it. And then you're done.
17:37
In my family, we there was something called a no thank you helping. At every meal, you had to try what was presented in front of you. My mother only cooked one meal, so you had to try. And even if you hated liver three weeks ago, you still have to try it. It's called a no thank you helping. So that's what this is. The other rotting food that's kind of gross is Sardinian pecorino cheese that goes through two-stage fermentation. The first one is microbial.
18:08
And then the second stage is actually the larvae of sheep flies. They're little, tiny flies that land. The cheese is cut open and they're invited to come in and land and lay their little eggs. And the larvae eat up the cheese and make this kind of soft, gooey stuff.
18:31
So there it is. My husband took this picture. We were in Sardinia in the beginning of October. And you can actually see, with this picture, what's happening, I think with microbes. You know, the microbes work the same way that these larvae do. So it's actually quite delicious, if you like a strong cheese. It's sort of like a Gorgonzola. It's kind of soft. And you just have to get over the bugs. And I said that to my husband, and he said, "They are not bugs." Anyway, it's delicious.
19:09
But it's also very acquired. And it is kind of ammoniated as well. So we're going to shift from larva and cheese to bread. And I'm going to make a loaf of bread, and you are going to try bread in three stages. Katherine works in our pastry department at Rialto. And she made three different batches of bread. One she started on Friday. KATHERINE BURCHMAN: Friday. And then Saturday. And then yesterday. JODY ADAMS: Yesterday. So the bread fermented. It's the same recipe.
19:47
It was all baked this morning, but it's three different fermentations. So the flavor in bread comes from yeast, water, flour and salt. That's all that's in there. It has a tiny bit of molasses in it, actually, but it doesn't necessarily certainly have to have it. It's dependent on those things, plus times, plus temperature.
20:09
The water is mixed with the yeast. The yeast is hydrated. And then that hydrated yeast, the enzymes work on some rogue sugars, apparently, that are floating around in flour from milling. There's some damaged cells that sort of kick-start the whole enzymatic process. So we need the big starch molecules, that are big and knotted, to be broken down so that the yeast can actually eat them and produce alcohol and carbon dioxide. So the yeast, as I said, the enzymes break down
20:56
these big molecules to glucose and fructose, producing alcohol and carbon dioxide. And then if you allow the bread to go through a further fermentation-- so the ones that were fermented from Friday, then some bacteria come in and they start eating up the maltose and it goes through this second fermentation that produces acids that give sourdough its flavor. And that acidic content in a bread will help preserve the bread, so sourdough breads have a longer shelf life than ones that aren't sour.
21:32
So I'm going to stop all that talking for a minute. We need just a little bit of yeast. Like that much yeast? KATHERINE BURCHMAN: Yeah. It's two teaspoons to this recipe, but we're just going to eyeball that. JODY ADAMS: Oh, did I put the recipe-- there. Two teaspoons of yeast. A couple of tablespoons of molasses. KATHERINE BURCHMAN: That's strictly for flavor. JODY ADAMS: And it can kick-start the yeast. But it's not necessary.
22:12
And then we have about two and a quarter-- KATHERINE BURCHMAN: That's two and a quarter. JODY ADAMS: Two and a quarter pounds of white flour. KATHERINE BURCHMAN: We want half of that. JODY ADAMS: And this is whole wheat.
22:27
And then we have a couple tablespoons of salt. Very scientific.
22:39
So you can do this, of course, in a mixer. But I think that if you're making bread at home, the satisfaction of kneading dough is really worthwhile.
23:00
And I'm going to get this started and then, of course, turn it over to Katherine.
23:05
KATHERINE BURCHMAN: When it gets too messy. JODY ADAMS: When it gets really hard. So what we're doing is, the yeast is going to be distributed in here. You don't really have to proof the yeast, unless you think you've had the yeast for 100 years and it's completely dead. Proofing the yeast is re-hydrating it, bringing it back to life, and proving that it's alive because it bubbles up. But you don't really need to do that. What happens with bread is that-- right now, what I'm doing
23:42
is developing the gluten. The gluten is the protein that are forming strings, so that when the dough rises, it has a structure. And if you are making a pie crust, you don't want to develop the gluten. You wouldn't do this. You wouldn't knead the dough.
24:08
There are some doughs that don't need to be kneaded, and that's because in fact, just the action of the yeast fermenting gets the gluten going. There's enough activity, actually, that the gluten will develop that way. But they tend to be a softer dough. And we want this to have some structure. So when you're kneading dough, see, you can get your exercise.
24:46
As long as you're using your core.
24:56
But this is really fun to do. Honestly. We spend so much time saving time so we can go to the gym and do this. Why not make a really beautiful batch of bread?
25:13
OK, go at it, Katherine.
25:18
I already went to the gym today.
25:23
KATHERINE BURCHMAN: You're really strong. JODY ADAMS: Well, you have to stand with your Pilates stance, like this. Like you're boxing.
25:34
So we're going to let that-- actually, my hands are covered with gluten.
25:43
But isn't it exciting to know that what we're doing here is developing this gluten? So we're setting it up for success.
25:55
So as the yeast is giving off all that carbon dioxide, and most of the alcohol is going to go off into the air. But the carbon dioxide is coming up, and the gluten strands are holding it all together, so you have this beautiful structure. If they break, if you over-proof a dough, you end up with a cottony bread. You know how Wonder Bread is really cottony? It's because it's way over-proofed. If you want a dough that has a nice, even structure and also great flavor,
26:28
you don't want to use a lot of east and you want a slow rise. So what we do at Rialto, actually, is add ice to the dough. So instead of three cups of water, we would have used-- this is actually wrong. This is supposed to be pounds of flour.
26:49
But that's not 10 minutes. KATHERINE BURCHMAN: OK.
26:55
You got it.
27:00
JODY ADAMS: So we're going to put it in a bowl, and put in a little bit of oil. The oil it just helps it slither up the sides of the pan as it rises. It also, if you will roll the ball in the oil, and it will protect-- KATHERINE BURCHMAN: Also, if you're going to cover it, if you have oil on the top and as it rises, it won't stick when you're taking the cover off, which is super annoying. JODY ADAMS: And it won't dry out, either. Then what we recommend you do is actually
27:35
make a line where the dough started, if you're a first-time bread baker. You put the dough and you cover it. You let it rise. It can take an hour, if you put it in a warm place, it's going to rise. You're going to have a dough that doesn't have very much character. It's going to be a fairly sweet dough, because the yeast will not have gone into the second fermentation, which is with the maltose producing the acid. It will have broken down the starch molecules of the flour into sugars.
28:13
So you'll still have some sugar in there. Once it rises, it'll look like that. You can see all the bubbles in there. That's the carbon dioxide coming up. And that's the right amount. You don't want it to go much more, or as I said, it's going to be cottony. Then you dump it out onto the counter, and you make a beautiful bread. We're not going to have time for that. But we are going to let this rise while we talk. We also, at Rialto and also at Trade, we let our doughs rise overnight
28:48
in the refrigerator. Makes a much more interesting flavored dough. And sometimes let them go for two days.
28:56
And then you have a happy daughter.
29:02
She's 18 and she's in Paris right now, and she would hate me if she knew I do that. I couldn't resist. So you have, on your plate, three different breads. You want to start with the one-- where are our students? KATHERINE BURCHMAN: I think they said the red or the yellow toothpick is from Friday's batch of dough. JODY ADAMS: So you want to start with the one that doesn't have a toothpick in it. KATHERINE BURCHMAN: Yesterday's? JODY ADAMS: Yesterday's. KATHERINE BURCHMAN: No toothpick.
29:34
JODY ADAMS: No toothpick. KATHERINE BURCHMAN: Saturday is blue or green. And then Friday is yellow or red. JODY ADAMS: OK. So go none, and then blue or green.
29:49
Oh, god, let's write on the blackboard! Zero is Sunday.
29:58
KATHERINE BURCHMAN: Green or blue is Saturday. JODY ADAMS: Green or blue is Saturday. KATHERINE BURCHMAN: And then red or yellow is Friday. JODY ADAMS: Red or yellow is Friday. OK. I think you want to start with the sweeter one, and then go to the one that has more flavor. Pretty interesting, huh?
30:26
You don't always want to make a sourdough bread. If you're making a Danish pastry that has a lot of butter in it, you don't want it necessarily to have a lot of sour in it. There are other ways of flavoring bread, other than fermentation. You can change the liquid that you're using. Milk. You can add milk to make it richer. You can add cider. You can add buttermilk. Buttermilk's a favorite. You can add fats to it, which will make a softer dough.
30:59
Oils or butters, because they're going to cut the gluten. They're going to soften the gluten. You can add other sugars and more sugars. You can add eggs that will enrich the dough. Different kinds of grain. Rye corn buckwheat.
31:20
KATHERINE BURCHMAN: We use a bulgar. JODY ADAMS: Cracked wheat. Bulgar. Sprouted grains, nuts and seeds, herbs and spices, dried fruits, cheese, vegetables, chopped vegetables, vegetables puree. You can use a vegetable puree as a base. But those are going to ferment. Just anything sweet you add is going to add to the fermentation of the bread. And meat.
31:46
Was that interesting? AUDIENCE: Yes!
31:51
JODY ADAMS: I'm used to teaching like 20 people, and we have a nice dialogue going. OK, so I didn't finish this process. So the enzymes in yeast act on the glucose and the fructose, producing the alcohol and carbon dioxide. Then we have the sourdough. And then the heat the oven works with the acid in the alcohol as it rises. It's called-- what's that called? Because it will continue to rise in the oven. Oven spring. That's right. thank you. Oven spring. And it produces esters.
32:32
So the alcohol and the acid come together and produce esters. And that's where you get the nice, fabulous aroma of bread. And it's that aroma that induces feelings of warmth and memory and bring people back.
32:55
OK, so now I'm going to make yogurt. So we'll move over here.
33:04
So that was yeast fermentation. And now we're going to talk about milk fermentation.
33:16
Yogurt is the easiest thing in the world to make.
33:21
And it is so good for you.
33:28
So now you're getting a taste of milk. Milk. Start with milk. KATHERINE BURCHMAN: Here you go. Here are your starters. JODY ADAMS: So we're going to bring the milk up to about 180 degrees. That 180 degrees denatures the proteins, which helps with the physical structure of the yogurt down the road. So you don't end up with curds. You just end up with a solid mass.
34:05
Can you go see, do they have the big jar of yogurt?
34:13
Once it's at 185 degrees, you let it cool to about 115. And then you can mix in either yogurt or a yogurt culture. And I just discovered this. I know I'm not supposed to advertise. But this company online, their cultures don't have anything in them except organic milk and live cultures. Some other ones have other kinds of sugars that they've added, but this is just that.
34:51
And this amount of yogurt will help turn 42 ounces of milk into yogurt.
35:10
KATHERINE BURCHMAN: Did you need a big jar? JODY ADAMS: No, I wanted to show-- is there a big jar of yogurt back there? KATHERINE BURCHMAN: I don't think so. They're spooning it out right now.
35:22
JODY ADAMS: Yogurt is incredibly forgiving. I had to make a huge batch of yogurt last night, and I once I got it into the jars, I thought, I don't have my groovy little-- this is a groovy little yogurt maker. I didn't have anything like this for this much jars this size. So I just put it in the oven at about 110 degrees. I kept checking it, and it actually stayed in there overnight. It was a very slow fermentation overnight. So what's happening is the bacteria are eating the sugars and the milk.
36:07
The lactose in the milk. And producing lactic acid. And because the sugars are eating that lactose, well, a bunch of things happen. One of them is you get this great acidic flavor of yogurt. You also have a milk product that now has tons of good microbes in it. It's a very good, healthy thing for you to eat. And the third is that it's pre-digested the lactose. So people who have any kind of lactose problems are able to eat yogurt much more easily than they can fresh milk.
36:51
That's going to take forever to turn to 180 degrees.
36:56
Fermentation does take some time and preparation.
37:01
Once you've mixed the yogurt or the starter into the warm milk, then you put it into jars. You put it into a place that has a temperature of about 110 degrees, and you let it incubate. It takes at least five hours. I like to leave it longer. Sometimes, even in these little jars, I'll let it go in for nine hours. You get a more interesting flavored yogurt. It's a little more acidic. And then you just put the tops on, and put it in the fridge.
37:33
And of course it lasts a really long time, because it's fermented. And this company sells these-- not this company, but anyway-- sells the tops, and you can put the date on it . You turn the little knob and it tells you what the date is.
37:54
So you keep track of how old your yogurt is.
38:07
The other kinds of fermented milks that are also delicious. Yogurt. Kefir.
38:14
Kefir actually has, I believe yeast in it, as well. It's more complicated culture. Clabber, which is a kind of a cheesy kind of a thing. And then skyr, which is another Icelandic sort of yogurt that apparently now is quite solid, but originally was more of a more liquid kind of a drink. And they're all slightly different in what the bacterias are that cause them to ferment. But originally, probably, somebody was carrying milk around in a bag
38:56
and there were microbes and bacteria in the bag, and the yogurt just happened.
39:08
Any questions? AUDIENCE: Does yogurt have alcohol [INAUDIBLE] fermentation [INAUDIBLE]? JODY ADAMS: Does yogurt have alcohol? I don't believe so. Unless there was a yeast that was introduced to it, I don't believe so. But I don't know. Does anybody know? I don't know that these bacteria produce alcohol. No.
39:39
I'm going to come back to that once the milk is done. But in the mean time, I'm going to make pickles. Or did you try your yogurt yet? Or did you just have milk? Just had milk. OK. Yogurt's coming.
40:16
Yogurt is also not something that you have to eat with fruit in the bottom.
40:23
It's really delicious to just eat it by itself, if you have a really good yogurt. And I would highly recommend that when you're buying yogurt, you look at the package. And if there's any additives, if there is anything other than yogurt culture and milk, I would stay away from them. There's really no reason. Yes? AUDIENCE: [INAUDIBLE].
40:52
JODY ADAMS: The way to thicken it is by using-- this is actually a Greek yogurt culture that I have here, that I haven't actually tried.
41:05
And it calls for heating it to a slightly lower temperature. So I'm not sure what will happen with this. But the way to make Greek yogurt is to put it in cheesecloth. It's getting rid of the whey. That's how it's thickened. Don't add a thickener. A lot of these Greek yogurts, they've added something to it to thicken the yogurt, and it's not a Greek yogurt. And if you're going to eat yogurt, eat whole milk yogurt. We're allowed to eat fat now. It's good for you. It's satisfying.
41:42
We use yogurt a lot, as a condiment, as an additive, as a balance to lots of different kinds of dishes.
41:57
Let's say you have a rich butternut squash soup, and it's sweet because of butternut squash, and you want something to balance the sweetness. Then you add some acid to it. And the acid in this case would be yogurt. Really refreshing. Really delicious.
42:17
If you think about adding-- you take a bowl of yogurt and put in raisins, and you put in granola that's laden with sugar, and then you add some nuts and honey, and blah, blah, blah. You're putting all this sweet stuff into yogurt. Think about doing the same thing, but use savory ingredients. Use tomatoes and cucumbers. Put some garlic in there. Put some nuts in there. It's a really delicious base. Yogurt! Here comes yogurt.
42:52
So this was made with a traditional culture, whatever that means.
43:01
But these bacteria like the heat. That's why we heat the milk. Not just to denature the protein, but also to provide an environment that the bacteria like. KATHERINE BURCHMAN: It's heating up. I can see the steam. JODY ADAMS: It needs to be almost bubbling.
43:32
OK, let's do pickles. KATHERINE BURCHMAN: Want me to take it out? JODY ADAMS: Yeah.
43:44
So now, while we're waiting for our yogurt-- and this won't take very long.
43:57
OK, so we have taken cucumbers and removed the ends from them. Apparently, they start rotting from the outside in. So you want to take those ends off. We soaked them in water.
44:16
We're going to put them in here. You want to put them in a clean jar.
44:28
I know we're adding grape leaves to make them crispy. Because the tannins in the grape leaves help keep the cucumbers crispy.
44:50
And I don't know why that is either. And then we're going to throw in some peppercorns.
44:58
You can put dill in here. And you can put all kinds of flavorings. And these are pickles, and these are fermented pickles. The pickles that you get that are preserved under vinegar are not fermented pickles. They're still pickles. And the vinegar's fermented, but they're not fermented. What happens here is the naturally occurring bacteria on the outside of the cucumbers --without oxygen, because we're going to pour the water over them-- start
45:37
to eat the naturally occurring sugars on the outside of the cucumber, and they ferment. And they give off acid and gas. And you leave the top off, particularly in the beginning, to allow the carbon dioxide to go out, otherwise you end up with my apple butter that explodes.
46:00
But the acid stays here with the cucumbers, and it sours them. And initially they're kind of salty, but then the salt is balanced by the acid. So we're giving you now a cucumber and a pickle.
46:26
I like these because they don't have very many seeds in them. I like smaller ones. Yeah, these are sort of like the Persian ones. Do we have more?
46:42
So they would fit better into this jar. In a bigger jar, you can just drop them.
46:52
AUDIENCE: [INAUDIBLE].
46:57
JODY ADAMS: Possibly, but I wash them.
47:02
But it seems to work. I would bet that the bacteria on the cucumber beats out the other ones. Should I go faster? MICHAEL BRENNER: No, I wasn't trying to speed you up. We just have microphones if anyone wants questions. JODY ADAMS: Am I getting boring? MICHAEL BRENNER: No, you're not boring. No, this is great. JODY ADAMS: So the other thing you want to do is when you're doing this, you want to put something on top that's going to hold all of the-- is my pickle jar back there? Or no.
47:40
You need to put something on top to hold the cucumbers under the water so that they don't interact with oxygen.
47:49
My guess would be that, about your question about the grape leaves, is that the bacteria in the pickles that produces so much acid is making the environment not a place for other bacteria.
48:07
I mean, that's why it's a method of preservation. There are all kinds of other bacteria.
48:25
KATHERINE BURCHMAN: It's at 140. JODY ADAMS: These are the cucumbers that we used. And some of them are even smaller, as you can see. These are nice, little ones without a lot of seeds.
48:50
So in here, we have these weights.
49:01
Can you see this? No.
49:10
It's turned a little bit cloudy. This is about two weeks.
49:20
And these cucumbers were a little smaller.
49:29
You can see, though. They look like real pickles, right? Pretty cool. It's so easy. You're going to want to start your own fermentation program in your house.
49:45
OK, we're going to cheat a little bit, because I'm going to finish this up. You can see the difference in the color and what happens. And clearly, that's acid. And all that is salt, peppercorns, and garlic, and water. It's all the acid from the fermentation.
50:18
We used up all our bowls, didn't we?
50:25
Here, I'm going to use this.
50:38
So I'm going to put my yogurt in here.
50:51
Add a little bit of milk.
51:15
AUDIENCE: [INAUDIBLE]. JODY ADAMS: To temper it a little bit.
51:41
It's to temper it, to even out the temperature.
52:24
This milk is way too hot. You can see it's curdling. I should have let it cool down before I did that. AUDIENCE: [INAUDIBLE] JODY ADAMS: No.
52:46
I was going to point this out. This was kind of obvious. If anybody could see that was happening. So I will tell you what you do when this happens, because I've done this before. I'm going to have a yogurt that is slightly curdled. And so you put in a cheesecloth and you drain it, and you have cheese. And you don't tell anybody that you screwed up your yogurt. KATHERINE BURCHMAN: It's true.
53:17
JODY ADAMS: So temperature and time, obviously, are very important. But this little gizmo, if you want to make your own yogurt, if you want to start being super healthy and without being obnoxious about it, just in a good way, with great flavor. This is a really good little machine to have. Can you see it?
53:43
So you have a whole fermentation program right here. Without even trying.
53:55
I think the pickles are so exciting. And I remember, when I was a kid, there was a sandwich shop and it was actually-- does everybody know who Wiley Dufresne is? So his father had a sandwich shop called Joe's in Providence, where I grew up. He went to RISD and he opened up first a sandwich shop called Joe's, and a restaurant called Joe's upstairs, which was a very cool place. And in the middle of the sandwich shop was a barrel. And in the barrel were pickles.
54:24
And in my memories, they were just floating. I don't think we stuck our hands in. But I remember they must have the plastic top on them, or something. Because I can't imagine that you just kind of walked in and looked at the pickles. But they were just floating around in there. And that's what they were, is this. Did anybody go to Joe's? Did you go to Joe's? It's Jeff's now. It's not nearly as good. It's really dirty.
55:01
I hope I didn't screw up the pickles too. No, you keep it at 70 degrees. OK.
55:09
As I said, for the pickles, there's naturally occurring bacteria on the outside of the pickles. They interact with the sugars. They like being in a salt brine at a certain temperature, which is about 70 degrees. And they will start fermenting. And what everybody says, when you're reading about them, is taste, taste, taste. And when they get to a point that you like, put them in the fridge. Keep a cover over them. You want to cover them up completely, because they're fermenting
55:43
and there's gas coming off, and they could pop the top off something. Put a cheesecloth over the top. Just put them on your counter. Don't put them in direct sunlight. And just let them hang out. You want them to be in something with a fairly wide top, not super narrow, because they pretty much guarantee they're going to develop mold. And you just skim that mold off. And be diligent about that. I had two going at the same time. I had this one and I had another one that was more this size,
56:18
and I ignored the small one, and the mold got into the pickle flavor. So I had to dump them out. But the other, this one, I just kept skimming. Are you eating pickles? Did you like the pickles? You wouldn't say no anyway. You could say no once I leave. Yes? How long? They took about 10 days before I put them in the fridge.
56:46
And that salt solution was three tablespoons per quart, which is, I think, about 5% solution. You can work with a lower salt solution if you want, if you don't want them quite as salty. It'll take longer.
57:11
So fermentation is preservation. That's what we've talked about. We've talked about flavor. The flavor of those pickles is great. We add pickles to everything. We add them as accents, garnishes. Think about adding olives and capers. All of those things that have big, bold flavors. That's what give food its depth, and it's what gives food it's memory quality for you. You're going to remember that pickle much longer than you're going to remember the cucumber.
57:42
And it's going to stay-- the flavor's going to stay in your mouth much longer than a cucumber. So it's important to have those kinds of flavors in food. And if you don't have them, then food is really boring.
58:00
Fermenting is also, obviously, about preservation and preserving milk with yogurt, cucumbers to pickles, and bread. Sourdough bread . It's also very healthy. As we talked about in sourdoughs, the pre-digested culture-- oh, no, we didn't talk about this, but the pre-digested culture of bread reduces the presence of gluten, making it easier for us to digest. So because the bacteria has started breaking down, more of the sugars in the gluten, it's easier to digest than a non-sourdough bread.
58:46
It also lasts longer. Yogurt, is the same thing is true, as I talked about. And pickles, there are also good things that happen, like vitamin B, that come into play.
59:03
Fermentation is also a really good thing for the planet. I met a woman the other day who is the CEO of a company that has, she called them, anaerobic digesters. And they're these huge machines to collect waste. Organic waste. And they're digested, and it produces methane gas that's used as fuel and produces fertilizer. And this is the kind of process that we should be supporting and looking for, because we need different kinds of energy.
59:41
So I think we need to stop the war on microbes. Stop sanitizing so much. We are microbes. We are covered with them, inside and out, and we need to remain that way. They provide a protection against bad microbes who want to attack us. And without them, we're vulnerable to colds, infections, and allergies. I think allergies is a big one that people are really interested in.
1:00:18
So when I started as a cook 30 years ago, flavor was something that we found in big fats, lots of meat, butter and cream. And over the years, as I've aged and my interest in food has shifted, I've become much more interested in foods that have big flavors coming from somewhere else. In this case, with fermented foods that really makes food, as I said, much, much more interesting. Much more fun to play with. And really fun to watch what fermentation is doing in our kitchens.
1:01:05
Look for flavor. Look for it in the right places, where it really makes a difference, and brings memories, and makes you feel good, and you can be experimental and have fun. Thank you.
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