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Episode 7

How Does Beer Get Its Bubbles?

Bobby and Allison take Gary to the church of foam and carbonation to explore how beer gets its bubbles. They discuss the molecularly sticky nature of proteins, the dangers of CO2, and the potential effect of other gases on beer.

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--

CREDITS

Hosts:

Bobby Fleshman

Allison McCoy-Fleshman

Gary Ardnt

Music by Sarah Lynn Huss

Recorded & Produced by David Kalsow

Brought to you by McFleshman's Brewing Co

Mentioned in this episode:

Join us for Lager Fest on October 5

Get your ticket today for a commemorative glass and all-you-can lager from over 20 breweries! https://mcfleshmans.ticketspice.com/lagerfest-2024 Music by Dvorak Polka Kevin MacLeod (incompetech.com) Licensed under Creative Commons: By Attribution 3.0 License http://creativecommons.org/licenses/by/3.0/

Transcript
Gary Arndt:

Welcome to another episode of Respecting the Beer.

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My name is Gary Arndt.

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And with me again is Bobby

Fleshman and Allison McCoy.

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We've talked about.

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Sight, how a beer looks, we've

talked about smell, it's aroma.

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Today, we're going to talk just

specifically about one aspect

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of, of how something looks, and

that is bubbles and carbonation,

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a really important part of beer.

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We've talked to in an earlier episode, but

the reinheitsgebot and the rules about how

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beer could only have three ingredients.

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It could have yeast, malt,

and hops now, I guess.

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But.

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There really is another ingredient

and that ingredient is dissolved

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carbon dioxide in most cases, where

does the carbon dioxide come from?

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How important is it in the

process of making a beer?

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Because we're going to get into

it because not all beers have the

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same level of carbonation, right?

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Bobby Fleshman: Fermentation

did really cut to the chase.

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The core of fermentation is to turn sugar.

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into one part alcohol, ethanol,

and one part carbon dioxide.

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And you'll get one molecule of

each at the end of the process.

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There's a million other steps

along the way, but that is

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the core of what's happening.

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And in order to do that, you have to

have yeast and you have to have the right

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food source, a sugar they can consume.

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And that's the job of

the brewer, the maltster.

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Gary Arndt: Is the implication of

that, that a higher alcohol beer

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is going to have more carbonation.

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Bobby Fleshman: If you, so

that's a great question.

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It will produce more.

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we can't because of the laws of,

of Henry's law, we can't possibly

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imagine a way to contain it.

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We could maybe from a engineering

standpoint, you would be

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talking thousands of pounds of

pressure at the end of the day.

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but from a, from a yeast standpoint, they

would obviously not enjoy that too much.

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Alison McCoy Fleshman:

I have to interject.

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I'm so sorry.

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So you can't just say Henry's Law and

assume that everyone knows what that is.

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Bobby Fleshman: And that's

why I opened the door here.

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Alison McCoy Fleshman: Anyway,

so you've all been there.

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You've shaken up a bottle of

soda and then you open up the

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soda and guess what happens?

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It goes everywhere.

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That's Henry's Law.

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So the more CO, so CO2 does

not want to be in the water.

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the water.

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And so it's going to escape,

and it's a gas, so it's going

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to escape out of the liquid.

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And so Henry's Law tells you

how much of that CO2 you can get

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to actually stay in the liquid.

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And when you open up that shaken

soda, Henry's Law is like, nope!

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Won't stay in.

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So out onto you, it comes.

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Bobby Fleshman: Right.

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So we live and die by Henry's law and

brewing, whether we know it or not.

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And it, we can use it when we're using

gas blends and nitrogen and CO2 and so on.

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But yeah, you were saying, does

the higher alcohol beer end

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up with higher levels of CO2?

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No, we tend to, to only leave

in it what we need for balance.

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Most beers are.

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coming in at, with a, with a range,

but, but they're, they're all in

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the sort of the same category.

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Alice is waving.

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Alison McCoy Fleshman: But so when

you have the big fermenters and we've

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normally got the fermenters, this is

the place where we're going to have

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the yeast eating the sugar, pooping out

the CO2 and pooping out the alcohol.

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So we have a hose that goes down into a

bucket and that bucket is continuously

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just bubbling and gurgling, and

really we walk by and we're like,

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Oh, the yeast are eating and happy.

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But I'm guessing for the higher

alcohol Beer is just more CO2

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escapes and we just don't keep it in.

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So you're talking about final

product CO2 in the beer.

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Whereas I think Gary's talking about

just in the overall process, it should.

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So he's right.

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It should create more CO2.

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Bobby Fleshman: And next step around here.

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One of our millions of

projects is to reclaim it.

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So once we have it.

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We can clean it, make it pure, use it for

what we call tank purging, line purging.

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The purpose there is that we want

to make sure that our finished beer

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doesn't come into contact with oxygen.

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So we create inert environments.

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Alison McCoy Fleshman: Speaking of CO2

in the brewing industry CO2, so it was

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originally known as fixed air and I

believe, Joseph Priestley back in the

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day, gosh, this was like 1800s or so.

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or maybe 1700s.

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He was an English chemist and he

was playing around with it but

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it was called fixed air and they

did all sorts of tricks with it.

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And the thing is, is that it sinks

because it's more dense than so CO2 is

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more dense than the regular air, which is

oxygen, nitrogen and argon combination.

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And so if you happen to be a home brewer

and you are fermenting in a freezer,

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like a chest freezer, and I speak from

personal experience, if you drop something

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in that chest freezer and go in after it.

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Careful because holy hell does it

hurt when you just like embed your

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face into just a blanket of co2 you'll

pass out And this is actually how

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many people have died in fermenters

when they've gone in to clean them

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Bobby Fleshman: Yeah, you don't you don't

actually taste it, but it burns your eyes.

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Oh, it hurts.

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I think that it burns when

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Alison McCoy Fleshman: you can't breathe

it Yeah, so at least in that quantity

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Bobby Fleshman: Breathe it

but to no effect, right?

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Yeah And there are some non laughable

stories in the last 10 years Modelo

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had someone go into a tank to clean

it and the tank was full of CO2.

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They didn't have the right equipment.

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They passed out.

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One person follows them

and next one followed.

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Six people died.

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They went into this tank

to rescue one another.

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So this it's, it's a real dangerous

issue in the brewing industry actually.

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But let's, let's get out of that.

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We

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Alison McCoy Fleshman: have safety things.

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Gary Arndt: Yeah.

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Back when I was studying geology

in my inorganic chemistry class,

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remember we had this really long thing.

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Where we had to explain the process by

which CO2 became carbonic acid, right?

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in seawater.

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Is that process occurring in beer?

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Bobby Fleshman: Allison can speak

to that a lot, but you're, you're

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making carbonic acid and that's giving

you a bite in the finished product.

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And that's, that in addition to the

hop acids are giving you the balance

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you're looking for in the end result.

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Alison McCoy Fleshman: From my

understanding, it's not very much, it's

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not a high concentration of carbonic acid.

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Bobby Fleshman: Belgian beers,

however, go double the carbonation

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of, of a normal, say, English ale.

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So you might see more in that case

because it shifts that, that, chemistry

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toward carbonic acid away from CO2.

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I did want to say on the high

alcohol that opens the door to

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talking a little bit about high,

the effects of alcohol on bubbles.

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And they, and alcohol in, in

water tends to change the.

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Can you speak to that?

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Alison McCoy Fleshman: No, I was like,

have we even talked about bubbles yet?

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Bobby Fleshman: Right.

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We've, we're kind of coming from

it from the outside in, aren't we?

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So bubbles how do you make a

bubble and how do you destroy it?

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I think that's probably the best way to.

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about bubbles and beer.

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My, my men, one of my mentors in

brewing school was Charlie Bamforth

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and he's known throughout the

beer world as the Pope of foam.

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So he's obsessed with foam and by

proxy, I think I've, I've sort of

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become a little bit obsessed too.

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He's also a prolific writer of

football, the, the, the worldwide

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version of football, but that's

another conversation for another day.

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He, would describe bubbles and

make you cry at the end of the day.

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I'll do my best here.

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Bubbles are protein related.

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There's a certain molecular weight

protein that gives you the main amount

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of the main structure of these bubbles.

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Other elements to the story

include like your double ionized.

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metallic ions like calcium, magnesium,

and then you get in hop acids,

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Alison McCoy Fleshman: just stop talking

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Bobby Fleshman: Starches.

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Yeah.

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Alison McCoy Fleshman: Wait.

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I mean, and I, I'm a chemist.

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Bobby Fleshman: I don't have a

picture in front of me, but yeah,

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Alison McCoy Fleshman: Let me, let me try.

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so imagine you have a balloon

and you blow up that balloon,

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you have essentially a bubble.

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And so what happens is imagine now that

the proteins and all the molecules Bobby

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just mentioned are holding hands in this

nice kind of tight way and then gas.

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As in, when you're putting air

into the balloon, expands it out.

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So that's what's happening is

the CO2 is encased within these

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really well connected structures.

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And so they're just

really molecularly sticky.

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And so those proteins are love,

well, and this is what gluten

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is very sticky molecules.

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Anyway, and so the CO2 gets trapped

within these molecules that won't let

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it escape because CO2 wants to escape.

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This is why if you leave your beer

out for any length of time, it's

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going to get flatter and flatter.

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Flat means no CO2 anymore.

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And so because those CO2 molecules

want to escape, they are trying to,

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but they can't because those proteins

are essentially holding them in and

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not letting them escape very well.

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Bobby Fleshman: There's also that

Henry's law we spoke about too that

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there's a natural amount of co2 that

does remain at the end of the day Yeah,

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Gary Arndt: it seems you're talking about

there's two different types of bubbles.

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There's bubbles in foam, but then

there's the bubbles that come up from the

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bottom or the sides of a glass, right?

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Bobby Fleshman: So that's so

that's the co2 itself evolving

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in order to capture it.

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You have to create these these Structures

that I mentioned the compounds involved

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and then Allison mentioned how co2 likes

to leave that solution Well, you can

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think of the walls of these bubbles as

being Very thin layers of beer and so

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they might actually coalesce that is

one bubble becomes to become one They

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gas passing from one of the to the other

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Alison McCoy Fleshman: But the proteins

aren't those are strong more strongly

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Connected to the water and when I

say water I'm talking about beer

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So the proteins are more strongly

connected to the beer, which is why

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when you have Bubbles, they're not

going to form like soap bubbles that

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then rise up and then go float away.

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Because those proteins are still strongly

connected molecularly to the beer itself.

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Bobby Fleshman: Yeah, proteins

are not evolving away.

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CO2 is.

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And as the dry, I call it dry, dry foam.

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Sometimes people will see me

messing around behind the bar and

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it takes me forever to pour beer.

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It's not because I'm just trying to get

the perfect shot for a, for a magazine.

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It's because I'm letting the,

the beer drain out of the

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channels between all the bubbles.

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And as the beer drains out, what's

left behind is the, is the protein

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and the hop acids and the metal acids.

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that are calcium ions, which

is really what they are that

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are giving that structure.

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And then I'll pour beer

back on top of that.

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Again, I'll do it three or four times.

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And if you're patient enough, I'll

do it seven times and it'll come

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out like the, like a meringue.

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And if you've ever made pies and

you've made your meringue that

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you're working with proteins there,

you're the albumen of a, of an egg.

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So that's what I'm doing back there.

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I'm trying to drain the beer off,

make the bubbles have more integrity.

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And then the lacing will be profound

after you are finished drinking that.

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Alison McCoy Fleshman: We try not to

let him loose in the tap room too often.

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Bobby Fleshman: Well, there was one

more thing we should mention and we're

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right here on we're hovering on it Co2

and how it likes to escape nitrogen

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doesn't like to escape So these little

bubbles when adjacent to one another will

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remain adjacent to one another will not

coalesce So you have a very creamy foam

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top of your guinness because it's full

of these nitrogen bubbles That have no

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means of coalescing and going away that

that's the whole Story behind nitrogen.

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Alison McCoy Fleshman: I'm giving

Bobby the look that says you are

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absolutely wrong in what you just

said So nitrogen does want to escape

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the liquid so it doesn't actually

want to stay because it's nonpolar,

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Bobby Fleshman: Right, so but it can't

pass through the the boundaries that

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separate the bubble that you are correct.

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So they Yeah, yeah, there's

two parts of the story.

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So it has to get out of the beer Yeah,

but as soon as it encounters these

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films It's at the surface of the beer.

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It's a prisoner throughout the pint.

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Alison McCoy Fleshman:

And it's much smaller.

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The size of the bubble is so much

smaller for nitro based beers or

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nitrogenated beers than it is for CO2.

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Okay.

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Gary Arndt: So let's back up about this.

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You serve several nitro beers.

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Yes.

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How does the nitrogen get in the beer?

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Alison McCoy Fleshman:

Oh, we put it there.

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Kind of.

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Gary Arndt: So I'm just saying in the

natural fermentation process, right,

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this is not something that is story.

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Alison McCoy Fleshman: Yeast

aren't pooping out nitrogen.

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Right.

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Gary Arndt: Right.

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So.

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How do you do it?

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Because I know it's not just in beers.

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Pepsi's come out with

like a nitrogen version.

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Alison McCoy Fleshman: Wait, what?

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Are you serious?

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Yeah.

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Gary Arndt: You didn't see this?

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There's like Pepsi nitro.

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Alison McCoy Fleshman: Oh weird.

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Gary Arndt: Yeah.

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So it's, it has a different

feel and everything else.

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Where does the nitrogen come from?

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Bobby Fleshman: So we can't, we can't

tell this without talking about Guinness.

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they can, they decided, so we

make a lot of Cascale here and

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that's the old way of doing it.

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And you put beer into a keg, if you like,

and you add yeast and sugar and you let it

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referment and create its own carbonation.

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And that's how it was

done in the old days.

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And then you serve it through these

water well type handles that we call beer

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engines and people still celebrate today.

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Okay.

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As being part of the

old way of making beer.

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And that makes a creamy little foam

because of the way it's, that you disperse

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it through the tips of the system.

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And it's, and it looks

a lot like nitrogen.

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And in reality, the

story goes the other way.

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Nitrogen looks a lot like cask.

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Guinness decided it didn't

want to do that much work.

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It's a lot of work to do cask.

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Alison McCoy Fleshman: So much work that

we are, one of like three or four in the

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country that actually specialize in cask

conditioned ales, whereas in England,

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everyone does, but here, not so much.

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Bobby Fleshman: Less and less in England,

but that's a, Maybe it's changing.

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It is a pain in the ass though.

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But, I'm not sure where that came

in, but I just wanted to bring it up

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that Guinness came up with nitrogen.

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That's where it came from.

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It's an industrial

addition to the process.

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And, Today, how do we

do it in our brewery?

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We bought our entire brewing

system for two reasons.

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One reason where they came, it

came from the Czech Republic.

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Ultimately, maybe we'll talk

about our system in the future

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episode, but, one reason was so

I can make German lagers with it.

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And the other reason was

so I can make Irish nitro.

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The equipment is set up.

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To take on more pressure, I can

take advantage of Henry's law

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and I can actually put nitrogen

into a state in which it likes

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to be dissolved in the beer.

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And then from there we can

package it and deliver it through

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the standard nitro setups.

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But not many people have the equipment

that can go to those pressures.

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But I knew that these would

be the linchpins to what we

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would be serving down the road.

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Gary Arndt: Cask beers, which

you mentioned, if they go

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through the same fermentation

process, why are they flatter?

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or taste flatter.

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Why isn't that they don't have

the same level of carbonation

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that you find in say a lager?

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Alison McCoy Fleshman:

Because they are superior.

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Okay.

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Bobby Fleshman: Most days you'll

see me drinking our English IPA.

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I like the mouthfeel there.

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The reason though that they are that

way is because they are at atmosphere.

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And they are at 50 degrees.

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So they are whatever

Henry's Law say they are.

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Alison McCoy Fleshman: So Henry's Law

will also say that, I mean, and this is

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the, the, like I said before, if you leave

your beer or soda, out on the table it's

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going to equilibrate to room temperature.

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And so it's going to continue

to get warmer and warmer until

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it matches room temperature.

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And then that's going to cause more

and more of the CO2 to escape the beer.

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And so Henry's Law says more of the

gas escapes at the higher temperature.

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But I think cask conditioning, that

was how it was for the longest time.

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And so I think that the, the colder

beers, we didn't have refrigeration

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all the time back in the day.

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Bobby Fleshman: Cellars.

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Alison McCoy Fleshman: Yeah.

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So the cellar temperature

is what they had.

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Cause the casks were way down

at the bottom in the basement

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cause it kept it cooler.

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And so that's one of the reasons that

they had the hand pump technology.

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And the folks that used

to do this were called.

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publicans and they would work to

tend to the pub or tend to the

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firkins or the cask conditioned ales.

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But one of the things about

the casks is that it simulates

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what beer would have been.

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And so back in the day when we

didn't have the technology to have

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really high pressure CO2, because

under high pressure is not only

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expensive, but it's also dangerous.

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And until we had the infrastructure

to build these huge tanks to CO2 and

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regulate pressures and stuff, it was

way too dangerous to have anything in a

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wooden barrel to be under high pressure.

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Actually, you really even couldn't

because you couldn't seal it enough.

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Bobby Fleshman: First,

where do you get it?

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And then how do you purify it?

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How do you transport it?

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How do you integrate it?

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Yeah.

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These are all industrial developments

and, and everything was, was, quote

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cascadged at some point in the last

before 150 years ago, for sure.

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Everything was.

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Yeah.

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Yeah.

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Gary Arndt: So, in a cast, is

it literally just flat, so far

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as the carbonation has escaped?

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Bobby Fleshman: So no,

actually this is a process.

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So we, we have behind us down the hall,

we have, probably 50 Perkins, which

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are large casks ready to be tapped.

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And when you tap them initially,

you can't serve them because they

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have to do a, go through another

stage of what we call venting.

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They have to reach a

Beer is just like people.

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Alison McCoy Fleshman: We

all need to vent, don't we?

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Bobby Fleshman: So that takes

about a day, if not longer.

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Sometimes you get lucky and it's a few

hours, but usually it's going to be a

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little angry, little about the change.

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Alison McCoy Fleshman: Were the,

let's go back 150 years ago or 200

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years ago, were the casks still there?

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They were all just wooden

barrels at that point.

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Bobby Fleshman: They would

have been pitch lined.

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:

So like sap lined to keep them airtight.

368

:

Yeah.

369

:

Alison McCoy Fleshman: Didn't know.

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:

Mm hmm.

371

:

Because now we use these metal

for can things, the metal casks

372

:

and those are gloriously sealed.

373

:

Bobby Fleshman: Yeah.

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:

They were, they're glorious.

375

:

He's gloriously sealed then too, but you

know, this is a time before microbiology.

376

:

So there's a lot of bacteria

and a lot of contamination.

377

:

We call it house character.

378

:

But yeah.

379

:

But to Gary's point though,

that reaches a certain.

380

:

Level of carbonation finds equilibrium

with the atmosphere putting in, it's

381

:

not an entirely reversible process.

382

:

Allison knows more than me, but

putting the CO2 in and then, and then

383

:

coming back out, those are different

in terms of time scales and levels.

384

:

But you get, you get sort of, an artistic,

input on the whole process as a publican.

385

:

I wish that would come back because

we would have more accounts around

386

:

the state, people that knows

how to handle these cascades.

387

:

Alison McCoy Fleshman: But to

Gary's question, are casks flat?

388

:

The answer is that they

are flatter than lagers.

389

:

But they shouldn't be completely

flat as in have no CO2 at all.

390

:

There is going to be some amount.

391

:

It's just going to be

smaller than you're used to.

392

:

Bobby Fleshman: The lowest carbonation

beer that we make, beers that we

393

:

make are nitro beers, but believe it

or not, they have, they themselves

394

:

have carbon dioxide in them.

395

:

Alison McCoy Fleshman: Even more

so than our imperial stouts?

396

:

Bobby Fleshman: Oh gosh, imperial stouts

have three times as much as our nitro.

397

:

Yeah.

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:

It's just that there's so much

sugar in our imperial stout.

399

:

Alison McCoy Fleshman: Calculating out

how much carbonation, are you just saying

400

:

that nitrogen, because it's nitrogen,

doesn't contribute to carbonation?

401

:

Bobby Fleshman: Nitrogen does

not contribute to carbonation.

402

:

Alison McCoy Fleshman: Right.

403

:

But it's still, so, it's

nitrogenated versus carbonated.

404

:

Bobby Fleshman: Yeah, it's about...

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:

Alison McCoy Fleshman: so that's not fair.

406

:

It's a different gas.

407

:

That's cheating.

408

:

Bobby Fleshman: One, one thing

about nitrogen is, you guys wouldn't

409

:

believe it, you could hold in your

hand how much nitrogen goes into

410

:

600 gallons of, of nitro beer.

411

:

Alison McCoy Fleshman: Yeah.

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:

I would totally believe it.

413

:

Molecules are small.

414

:

Bobby Fleshman: It's astonishing.

415

:

Well, but by comparison, you're talking

about thousands of times more for CO2.

416

:

Alison McCoy Fleshman: Well, yeah.

417

:

It's bigger.

418

:

Bobby Fleshman: But the effect of

that tiny amount of nitrogen, it's

419

:

parts, it's 40 parts per million.

420

:

And Guinness revealed this recipe

on their, somewhere in their

421

:

history, in some scientific paper.

422

:

And sure enough, if you go

35, you don't get the cascade.

423

:

You go 45, half your

glass is full of foam.

424

:

It's remarkable.

425

:

It's, it's incredibly small amount,

but nitrogen, this whole, this whole

426

:

science of beer gas is, is fascinating

427

:

Alison McCoy Fleshman: to some,

428

:

Bobby Fleshman: to some.

429

:

Alison McCoy Fleshman:

No, it really is fun.

430

:

And if you have the opportunity to try,

a regular tap beer, a nitro beer and

431

:

then a cask beer all at the same time.

432

:

It's really fun to just to feel

the different mouth feel that you

433

:

get from the different bubbles.

434

:

Gary Arndt: Are there any

other gases that you could use?

435

:

Is nitrogen pretty much it?

436

:

And is it, does the fact that it's

inert, well, relatively inert, a nitrogen

437

:

molecule have to do with its use?

438

:

Bobby Fleshman: Yes.

439

:

but April 1st is coming, so

we should do that helium beer.

440

:

I think that should happen because

I want to see, there was a, I

441

:

think Sam Adams did this a couple

of years, it's been a decade ago.

442

:

They, they joked about doing it and they

were standing around drinking it and then

443

:

talking like they had consumed a balloon.

444

:

Yeah.

445

:

But

446

:

Alison McCoy Fleshman: I would say

like the closest relatives to co2 is

447

:

like so2 and you would not want sulfur

dioxide in your beer at all nitrogen,

448

:

i'm trying to think who the closet

449

:

Bobby Fleshman: relative

450

:

although sulfur dioxide preserves

the beer It would be disgusting to

451

:

Alison McCoy Fleshman: So gross.

452

:

No, don't do that.

453

:

but no I think conveniently you don't

want oxygen in your beer that's going

454

:

to cause a bunch of extra reactions to

occur oxidizing, that sort of thing.

455

:

You definitely don't want chlorine

in your beer, cause that'll kill you.

456

:

And chlorine's even worse.

457

:

Die faster.

458

:

So, don't do that.

459

:

Gary Arndt: In theory, could you

take a heavier, inert gas, like neon?

460

:

Alison McCoy Fleshman:

Ha ha, that'd be fun.

461

:

I don't see why not.

462

:

Gary Arndt: I mean, it'd

be kind of expensive.

463

:

Alison McCoy Fleshman:

Yeah I mean, it would,

464

:

Bobby Fleshman: I like

where we're going here.

465

:

Alison McCoy Fleshman: No, I don't.

466

:

well,

467

:

Bobby Fleshman: Five gallons of this.

468

:

Alison McCoy Fleshman:

It's to throw Argon in.

469

:

Why not?

470

:

Krypton, that'd be fun.

471

:

Gary Arndt: Argon would be cheaper.

472

:

Alison McCoy Fleshman: It would.

473

:

I think you, no.

474

:

Bobby Fleshman: Food grade Argon.

475

:

I'm gonna Google search that.

476

:

Alison McCoy Fleshman: I'm about to

look up Henry's constant on Argon.

477

:

Cause, yeah, We use argon to like

clean, clean different liquids and

478

:

we'll bubble it through to like catch

all the stuff as it bubbles out.

479

:

I think the Henry's constant

is just so big you wouldn't

480

:

actually have any of the gas stay.

481

:

Bobby Fleshman: One other fascinating

thing, I should, I should give

482

:

this to this tidbit to the home

brewers and the brewers out there.

483

:

You actually do not want to see foam

created in the brewing process or the

484

:

fermentation process any more than is

necessary because this is not reversible.

485

:

These molecules that made that foam

are lost forever for that application.

486

:

So you see, And throughout your packaging

and so on, you want to keep all your

487

:

foam down as low as possible beyond just

the loss of beer that's in involved.

488

:

So yeah, that's that's chemistry.

489

:

It only goes one way in that case.

490

:

Gary Arndt: So when you have you

pour a beer, there's foam at the top.

491

:

You let it sit for a little while.

492

:

That foam will eventually

go down and disappear.

493

:

Is all that, I mean, that's obviously

going back into the beer at that point.

494

:

Bobby Fleshman: No no.

495

:

The proteins themselves

496

:

Gary Arndt: I mean it's

got to go somewhere.

497

:

Bobby Fleshman: Well, you're probably

consuming them in the first few sips.

498

:

You're probably consuming most

of that foam off the surface.

499

:

The, the, the, the air that was

holding them bubbles up, CO2 is now

500

:

coalescing, gone to the atmosphere.

501

:

So it might be a little bit misleading

to, to interpret that much foam as

502

:

actually being that much material.

503

:

It might be 99 percent CO2.

504

:

So when it does completely evolve,

there's not much left to speak of anyway.

505

:

But it does, it does give you that lacing

on the sides, which is, Cathedral like,

506

:

if you listen to Charlie talk about it.

507

:

Yeah.

508

:

Hedonic was the word we used.

509

:

I'll never forget it.

510

:

It's purely hedonic.

511

:

Gary Arndt: And Allison,

do you have a calculation?

512

:

Alison McCoy Fleshman: I'm trying, I'm

looking, but the units aren't matching

513

:

up, so I'm having trouble, because no

one would ever put neon into liquid

514

:

because that doesn't help anything.

515

:

But Henry's constant is about 0.

516

:

03 for CO2, but then it's like 0.

517

:

0004.

518

:

in neon, but the units are

a little bit different.

519

:

It's really, really small.

520

:

So cause no neon wants to

stay in any sort of liquid.

521

:

So yeah, so brewers out there, sorry,

please do not put neon in your beer.

522

:

Gary Arndt: All right.

523

:

Well, is there any more

on the subject of bubbles?

524

:

Bobby Fleshman: I have

more than we have time for.

525

:

I did want to mention

decoction one more time.

526

:

A decoction is the way

that we handle grain.

527

:

If you go at it from the German

and the check way of doing things,

528

:

you, you, you cook it and you

can recombine it in the process.

529

:

The point I wanted to bring up here

though, is, is the heating and the

530

:

pH that and the time duration that

you apply on that barley and on

531

:

that malt gives rise to different

levels of molecular weight proteins.

532

:

And ultimately, you can create

amazing foam by doing decoctions.

533

:

I'm always going to be a

champion of decoction brewing

534

:

for more than one reason.

535

:

Alison McCoy Fleshman: I got nothing

to say to that other than everyone

536

:

doesn't like you at least in back

of house because of the decoction.

537

:

Bobby Fleshman: Until I put

the, the, the results in front.

538

:

Alison McCoy Fleshman: Oh,

it tastes so much better.

539

:

It really does.

540

:

But the process of it, well, it's

kind of like, you know, when you,

541

:

you know, you can bake bread.

542

:

you know, at home by yourself.

543

:

And like, you know, it takes

all this time, or you can

544

:

just go buy a nice bread loaf.

545

:

But then again, I guess that's what we're

in the business of is making liquid bread.

546

:

Bobby Fleshman: The team in the back

of the house are very pragmatic.

547

:

They say if it makes the

beer better, they'll do it.

548

:

And we put the test in front of them.

549

:

And if it, if it's better,

they will jump right in.

550

:

Alison McCoy Fleshman: Unless

it's the 36 hour brew day,

551

:

which is our Mike Santos, Ph.

552

:

D.:

553

:

Bobby Fleshman: Including that one, too.

554

:

They'll do that too.

555

:

Alison McCoy Fleshman: Yay for bubbles.

556

:

Gary Arndt: All right, well that concludes

another episode of Respecting the Beer.

557

:

Join us next week and until then,

please visit us over on our Patreon page

558

:

or over at the Facebook group links of

which can be found in the show notes.

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Respecting the Beer
A podcast for the science, history, and love of beer

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