Beer ingredients explained: malt, hops, yeast and water

There's a particular kind of satisfaction in pouring a beer you made yourself, and the way you get more of those and fewer of the disappointing ones is to understand what each ingredient is actually doing in there. Four things go into beer, which are malt, hops, yeast and water, and each one is responsible for a different part of what ends up in the glass. Nobody starts out knowing which is which. Everybody who brews well learnt it a batch at a time, usually by getting one of them wrong and tasting the result.

Malt is the body and the sweetness

Malt is where the sugar comes from, so it's where the alcohol comes from, and it's also where most of the colour and a lot of the flavour comes from. It's barley that's been sprouted and then kilned, and how far it gets kilned decides what it tastes like, so a lightly kilned malt gives you biscuity and bready notes while a dark roasted one gives you coffee and chocolate. That's the whole reason a stout is dark and a lager isn't, and it has nothing to do with strength, which is the thing people most often assume.

If you're starting out, use malt extract rather than grain. It's already been mashed for you, so you're skipping the fiddliest and most temperature sensitive part of the process, and you can still get a very good beer out of it. Once you've got a few batches behind you, a small amount of specialty grain steeped in the pot is the cheapest way to change what your beer tastes like.

Hops are the balance and the aroma

Without hops, beer would be sweet and a bit cloying, so what hops do first is provide bitterness that balances all that malt sugar. They also carry the aromas people go looking for, which depending on the variety might be citrus, pine, tropical fruit or something earthy and herbal.

When you add them decides which of those two jobs they do. Hops boiled for a long time give you bitterness and very little aroma, because the aromatic oils are volatile and they boil off, and hops added at the end of the boil or after fermentation give you aroma and almost no bitterness. That's worth knowing even if you're brewing from a kit, because the bittering has already been done for you in the tin, so anything you add is going in for flavour and aroma rather than to make the beer more bitter.

If the variety names are overwhelming, start with one you can taste clearly on its own. Citra and Galaxy are on the tropical and citrus end, Kent Golding and Fuggles are the earthy English ones, and Nelson Sauvin sits somewhere off on its own. Brew the same base beer twice with two different hops and you'll learn more in six weeks than you will reading about it.

Yeast does the actual work

Yeast is the only living thing in your beer and it's the part that turns sugar into alcohol and carbon dioxide, and it also throws off a lot of the flavour compounds people credit to the malt or the hops. Ale yeast works warm and tends to give you fruity and estery notes, and lager yeast works cold and slow and gives you something much cleaner, and that difference is the actual dividing line between an ale and a lager.

The single biggest thing you control here is temperature. Yeast that's too warm gets stressed and produces solvent and banana flavours that weren't meant to be there, and this is the commonest reason a first batch tastes off. Find the coolest steady spot in the house and put the fermenter there rather than chasing a number you can't hold.

Water is most of what you're drinking

Beer is about 90 per cent water, so it does matter, but for a kit brewer it matters a lot less than the internet suggests. The honest test is whether you'd drink a glass of it straight from the tap. If it tastes fine, it'll make fine beer. If it tastes strongly of anything, that taste is going to end up in the finished product, so use something else.

Adjusting water chemistry with brewing salts is a real thing that real brewers do, and it's also a long way down the list of what will improve your beer. Sort your fermentation temperature and your sanitation first, because those two are where the gains are, and worry about water minerals when you've run out of bigger problems.

The part that isn't an ingredient

You can buy the best malt and the freshest hops in the shop and still make undrinkable beer, because process matters as much as what goes in the pot. Sanitise everything the beer touches after the boil, give the fermentation the time it wants rather than the time you want, and write down what you did. That last one sounds like homework and it's the thing that turns a good batch into a repeatable one, because a beer you can't reproduce is a happy accident rather than a recipe.

Shop related products

• Coopers Light Malt Extract 1.5kg. A clean base for pale beers.
• Coopers Amber Malt Extract 1.5kg. More colour and caramel for ambers and browns.
• US-05 Safale Ale Yeast 11.5g. A clean, forgiving ale yeast.
• S23 Saflager Lager Yeast 11.5g. For when you want it cold fermented and crisp.

Did you know we also stock hop pellets in the shop, including Citra, Galaxy, Centennial, Chinook, Nelson Sauvin, Fuggles, Kent Golding and Hersbrucker, along with crystal malted grain for steeping. They're not on the website, so give us a ring on (08) 8536 4333 to check what's on the shelf.

The rest is in our homebrew beer supplies, and if you'd rather talk it through than read about it, Brewhilder is set up for exactly that.

More from the blog

• How to avoid off flavours in your homebrew beer
• From pale ales to stouts, experimenting with beer styles
• Everything you need to know about fermentation and bottling

I still read the back of the packet every single time, and I'd recommend it.

Candeece