The role of mashing in beer making


Today we're going to talk about mashing. Mashing's an important process. This happens in the brewhouse, as opposed to malting, and also the other agriculture, drying hops and all that, so this is actually, you have your malt now in the brewhouse, and what you want to do is convert that malt into something that the yeast can eat, basically sugar water. One way you do that is by grinding or making a grist of the malted barley. What exactly is mashing? Well, it's a brewing process that makes what we call wort, which is the word for the sugar water, and that is put into a fermenter and produces alcohol and also CO2 in the fermentation process, where the yeast actually chew on the sugar to eat, and the byproducts of it are alcohol and CO2. As I mentioned, wort's the name for the sugar water produced in the mash. Mashing is just a term for basically putting water over crushed barley at a certain temperature, as you'll see, and that creates the sugar water.

A rest is also important, because a rest is where we hold the particular temperature of water for a certain length of time, and it's different temperatures activate different enzymes, and those enzymes create different types of sugar. Depending on where your rests, or rests, are, you basically can control the body of the beer, how much sugar, you can control to some degree the alcohol, and a bunch of other things. It's important to note that all mash profiles, except for parti-gyle, so we're talking basically modern mashes, have a sugar rest. The other steps may be optional, and we'll see when we get to those mashes.

How do grains become wort? Well, they get ground up, as I mentioned before. They become a grist, G-R-I-S-T, and then they're mashed by adding water. Then after they're, water's put in there, we do what's called lautering. That's kind of like rinsing. The spent grains go out to the cows or the trash. Hopefully you're recycling them. If not, you can use them for fertilizer and other things. If you're a big brewery, a lot of them are now recycling those with local farmers and things like that. Then the wort gets boiled, hops and are added the sugars, if you add any adjuncts, whatever. It's cooled, and then you throw the yeast in, which is now way out of the realm of creating wort, but that cooled wort is actually, technically becomes beer the second you throw any yeast in it, because once a yeast eats a cell and produces a minute amount of alcohol, it's technically not wort anymore.


All right, so we'll go back historically. One of the original ways to make beer was with what we call a parti-gyle. That's from the British Islands. We know it's been used before the 11th century, and it was used extensively until about the 1700s. Remember, there was no instrumentation, really. If there was, it was very rudimentary, so people used things like, oh, looking at the wort to see what, or the water, depending on what they were doing, and they could, if they could see their face or not see their face, or the clarity of the shadow, that kind of things. That's how they kind of told how hot the water was. It's a very simple technique. You could usually make two or three beers or gyles.

In Belgium, it was called the turbid mash, so what you would do is basically get your crushed-up grain. You'd throw it in a pot. You'd heat up some water in a separate pot when you thought it was the right temperature. Remember, again, there was no thermometers. You would just pour it on top of the ground-up grain and maybe let it sit for a little bit to try to activate some of the sugars with the enzymes, and then you would just basically drain out that water, and you would have a clearish colored liquid that was called wort. You can usually make two or three beers. The first beer would be what's called the strong beer, usually the five, six, seven or maybe even more percent beer. The second beer was probably called the table beer, something like that. It was two, three percent. That's what people drank at dinner, lunch, for snacks.

They also would sometimes make a third beer, which might be one and a half, two percent alcohol, which kids would drink, because remember, people couldn't drink water back then, or if they did, they got sick due to all the illnesses, so they tend to drink a lot of beer, because they knew they would not get sick from that. Of course, they didn't know it was the boiling that sanitized the water. That's a parti-gyle. It's come back a little bit in homebrewing. I don't know of any commercial brewers that would do it. It's too inefficient and takes too much resources, really, but it's fun. I've made a couple, and the beer's actually won some awards, so that it's really nice.

Infusion mash

Then in the mid to late-1800s we got what's called the infusion mash. That was also called a single-step mash. Basically, you took the crushed grains and you added that to the water that was already at the correct temperature. You could pour the water on top of the grains or vice versa. Generally, especially if ... It works better if you put the grains into the water, because it soaks them up better. Again, we're talking about a sugar rest only. There is no other steps, but basically lower temperatures created more alcohol by making more fermentable sugars where higher temps created more dextrins, which the yeast could need, or long-chain carbohydrates, and the body gets bigger with that kind of beer. Most beers are probably in the middle, so you want alcohol, but you also want some body, but if you're looking to make a very full-bodied beer, you want to mash higher. If you're looking to get more, the most alcohol out of your grain bill, then obviously you're going to want to mash at a lower temperature.

They also added a mashing out phase at about 175, a hundred and ... Well, 170, 175. You don't want to go much higher, or you get that, the grainy flaw where you're pulling out extra bitter components, but that stops the enzymes, so it basic, effectively stopped the mash from creating any more sugars, which made the beer more stable and more consistent, where the parti-gyle, you basically had the warm water was still technically converting as you're pouring it through, so this really made an increase in the commercial viability of beer, because it could be more consistent.

Step mash

Then we modified this, the Belgians did anyway, and they modified the infusion mash. It was called step mashing, or a multi-step infusion mashing, but now the grist is infused with different temperatures, so it might be a protein rest, because traditionally, mainland Europe had malted barley that did not completely ... It didn't completely modify, which is basically a process where, when the malt, which you look on the malting slides, we'll talk about that more, but with a protein rest, they actually got the protein level under control, and there can be as many as five steps starting even down in the hundreds, maybe the high nineties.

Don't really need that today. That had to do with the way malting technology was back then, especially in mainland Europe. Britain pretty much had fully modified barley, from what I can understand. That's basically just a longer day, so you basically, instead of one temp and then put in your 175-degree water to shut everything down, now you have five steps. They may only be 10 or 15 minutes at each step, but it still makes for a longer day when you have three, four, five steps.

Decoction mash

Then the Germans had a decoction mash. It's very similar to step mashing, except instead of adding water, they basically removed part of the grist, brought it to a separate vessel, brought it to a boil through direct heat, and then returned it to the mash, which raised the temperature of the mash, similar to a step mash, by adding water, but this got more caramel flavors. It also stopped some of the enzyme action. Sometimes they do single, double, triple decoctions, depending. The Czech Republic, they still do that for a lot of their traditional beers.

Single just means basically they had a lower temperature, usually a protein rest. They take out maybe a quarter to a third of the grist that's there, bring it to a boil, and then send it back. It would raise the temperature up to the 150, 152 mark. If they did double or triple, they might take smaller amounts, or they would do other things. They've got formulas for that. I've never worked on that kind of system, so I'm not really sure of the exact temperatures things would be at, but it's easy to look up nowadays.

American Mash

Then we also have what's called the American mash, or a double mash, and that's similar to decoction, but not really. It was modified when the Americans or the settlers came over to America. They needed a large amount of adjuncts, because there wasn't as much barley and other things around, so they would use rice, corn ... Probably not rice at that point, but corn anyway. Malted and unmalted versions of grains at the same time, so basically they'd put all the malted grains into one vessel and all the unmalted grains in a different vessel, and they'd add a little tiny bit of crushed barley to the unmalted grains just for the enzyme reaction, so they'd boil those, boil that up and then throw it back in, and that would be malted. It's similar to a decoction, and it finishes pretty much the same. It's just two different ways to do that.

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