with crystal rye), which makes it a devilishly difficult grain to balance out. But Rye IPAs can be fantastic things in the hands of a good brewer.
OATS
Use of this hearty grain all but died out in brewing until a few years ago when the oatmeal stout made a comeback. Flavour-wise it’s hard to detect, but it can make for an exceptionally smooth mouthfeel.
HOW TO CONSTRUCT A MALT BILL
So we know the science part of the malt, but the art is in balancing all the varying, and often conflicting, characteristics. On top of that, you’ll have the drinker’s expectations that come from whatever style you decide to write on the label.
The first thing a brewer decides (after the style, of course) is what strength he wants the beer. This correlates to how much base malt you put in compared to how much water. There are lots of other factors, but that is the basic sum: more malt equals more booze. Sometimes when a brewer makes a really strong beer, they have to use all kinds of tricks to fit the malt in the mash tun (once I saw a brewer prop his sparge arm up with bricks to stop it skimming the mash).
The visuals come next. People drink first with their eyes (not literally, that would be agony), so you need it to look delicious. If it’s a stout, then you want it black as the night. If it’s an IPA, then you want it to glow amber like a golden chalice. Brewers have to think about mouthfeel, too. Lagers need to be light and zingy, so they can jump off the palate, while a weissbier needs to feel like velvet from the moment it hits your lips.
All the while, you need to focus on the most important thing: the flavour. It’s what we’re all here for, and your intention has to be spot on. If I’m drinking a black IPA, I want to taste the toast and liquorice as well as the grapefruit and resin. If it’s an American red, then I want crystal sweetness, but it should never be cloying.
Making a malt bill is a balancing act. It’s a part of the recipe a brewer rarely gets right first time because coming at the start of the process means everything you do afterwards will have an impact. And at no point is that more clear than during the mash.
By the time you head to work in the morning, the chances are every brewer in the country has mashed in and is wondering where his next cup of tea is coming from.
Brewdays can take anything from five to twelve hours, and then there’s a lot of cleaning up to do, so it starts absurdly early. Brewing collaboration beers or filming on location usually means we get the first train of the day, but it’s always worth it. The steamy aroma of a mash is, without doubt, my favourite smell in the world. It’s somewhere between a great cask bitter and a cookie fresh from the oven. However long you’ve been a brewer, especially on winter days, you can’t help but lean over the tun and breathe in the delicious, warming steam.
Mashing is the process of extracting flavour and sugar from the malt and introducing water to the beer. Hot water and malt are added to a mash tun – a giant vat with a filter plate at the bottom of it. There, it’s held at the best temperatures for enzymes to break down the starch into sugar, stirred most of the time by hand or machine.
The mash may sound like a giant porridge, but it’s where a huge part of a beer’s character comes from. It’s not just affecting the flavour, aroma and colour that we talked about in the last chapter, either – it controls the mouthfeel of the beer, too, and nailing that is very tricky indeed.
The Goldilocks Theory
If Goldilocks had broken into the bears’ house when they were homebrewing, she would have really had her work cut out. Mostly we talk about temperature when mashing, but there are a lot more variables at play. There’s sugar, enzymes and pH levels for her to judge too. The science of the mash is balancing them to get the perfect malty liquid – or “wort” – for the style of beer you’re making.
It’s worth noting here that no recipe is ever really “finished” – good brewers are always tweaking their processes to refine perceived flaws or to react to a shift in an ingredient. So there’s no right or wrong way to do a particular mash; there are only principles that every brewer interprets in their own way. This variation between styles and ingredients, brewers and breweries, is part of what makes beer so varied and exciting. But it also makes writing about beer almost as hard as brewing it. So cheers, guys.
The Right Amount of Water
The next chapter deals with the kind of water we need to use, but the amount of water in the mash is also key. Enzymes are pretty excitable, so if you don’t water down the grain enough they will go to town on the starch and covert it to sugar rapidly. The problem with that is they might do a half-assed job, and some of the sugar they create won’t be fermentable. The result is a fuller-bodied, sweeter beer. A mash with lots of water will result in a slower conversion, but more fermentable sugar for a drier beer. Neither situation is necessarily better; they are just suited to different styles of beer and brewing. A drier mash, particularly one with higher protein grains like wheat, does run the risk of getting “stuck.”
The Right Temperature
Now here comes the science bit. These enzymes I’ve mentioned only work at certain temperatures, and, inconveniently, they all work at different ones.
We could get bogged down in glucanase and peptidases – all the “ases” – but all we need to know is that these two help keep the beer clear and improve retention of the foamy head. More important to us are the alpha and beta amylases that break down the starch. Think of the alpha as a maniac lumberjack with a chainsaw who is chopping down trees at random, while the beta is a madman with an axe splintering smaller pieces off the trees. The yeast can only consume the small bits, so alpha doesn’t give them much to work with because it chops all kinds of sizes. Beta, meanwhile, chops at the bases and makes lots of little fermentable bits. Beta turns most of the starch to sugar, but it can only reach so high, so a little bit gets missed.
The reason I’m over-investing in this metaphor is because this is where the mouthfeel and lots of the flavour is decided. Because the alpha enzymes like chainsawing at high temperatures (around 70ºC/158ºC) and the betas want to start chopping at cooler ones (around 62ºC/144ºF), the temperature you mash at is vital to the rest of the brew.
If you mash at the lower ranges of the beta zone, you’ll end up with a thinner, drier beer. That’s because the betas broke down most of the thick body-providing starch chains, turning them into sugar that was eaten up by the yeast.
If you mash at a higher temperature, you’ll get fuller-bodied, sweeter beer because the alphas didn’t break down all the chunky chains of starch into sugar, leaving it unfermentable.
Most beers are mashed right in between these two ranges. It gives you the sugar you need while not taking away all the body from the beer. When writing a recipe, this is taken as the standard that the brewer deviates from to tailor his mash to the beer in his head. It may be he is making a big imperial IPA and needs all the sugar he can get, so he’ll mash in low. Conversely, if he’s making a 3.8% session IPA, he’ll mash high to leave some
