In my page on quick and easy beer I describe the minimum you need to do to brew a reasonable beer from the kind of kits you buy at the supermarket. These recipes are not cast in concrete, though: there are many things you can do to improve the taste of the beer and adapt it more to your personal preferences.

The most obvious one, of course, is to choose a style that you like. Coopers currently offer 18 different types. But all kits I have seen stick to the rule “1.7 kg malt extract, 1 kg sugar, ferment at ridiculously high temperatures”. In particular, the sugar and the yeast are issues. On this page I'll discuss ways to tweak the composition of your beers in ways that the manufacturers didn't intend.

The sugars

The most important component of beer is the malt, which contains a sugar called maltose. The yeast converts the maltose into ethanol (“alcohol”) and carbon dioxide.

Maltose is chemically very similar to saccharose, better known as cane sugar (or beet sugar, which is chemically identical), and nearly all yeasts will ferment it in the same way as maltose. Nowadays saccharose is much cheaper than malt, so one way to save on the cost of the beer is to use saccharose instead of maltose.

The problem is that the sugars ferment to ethanol, and don't contribute to the flavour of the beer. Malt contains a large number of other components which give the beer its flavour. If you replace the malt with pure saccharose (or, for that matter, pure maltose), you still get the ethanol, but you don't get any flavour. This is why full-flavoured beers are almost always made only from grain. Modern malting techniques highlight the flavour components of malt, so you can get a reasonable beer made from a wort containing 20% to 30% saccharose, and many commercial beers are made this way.

But how much saccharose do the kits use? The wort concentrate weighs 1.7 kg, which is about 70% maltose and other sugars, or 1.19 kg. To this you add 1 kg of saccharose, which thus makes a total of 45% of the total sugars. This is almost certainly too much. If you limit the amount of saccharose to about 20%, you're likely to get a better beer.

So: one way to improve your beer is to buy two cans of wort extract and forget the sugar. You'll then have 2.4 kg of sugars, so you can make a little more beer. It's not as much as you might think, though: the maltose ferments out pretty well, but the other sugars don't do so, so you're probably better off with 23 litres again, at least to start with.

This is the method I used to recommend on the quick and easy beer page, but it has two problems:

• The kits aren't just wort extract: they contain hop oils as well. If you just take two of them, the resultant beer will be twice as bitter.

  To understand this, you should know that the bitterness of beers is measured in IBU (International Bitterness Units, which happen to be parts per million of hop alpha acid in the beer). The mildest beers have about 20 IBU, which is barely perceptible; most are in the 25 to 30 IBU range. A beer with 40 IBUs tastes quite bitter, though some India Pale Ales go up to 70 or 80 IBUs. If you buy, say, two lager kits with 30 IBUs, your beer will have 60 IBUs, which is too much for most people.

  So what can you do?

  • You can buy unhopped malt extract. This looks exactly like the kits you buy in the supermarket, but it has no hop extract. Clearly it will do the job, but it's not easy to find. Home brew shops will normally have it at a slightly higher price than you pay in the supermarket.

  • You can buy very lightly hopped wort extracts if you can identify them. In Australia such information is not easily available. Potentially a “draught” or “pale ale” style might be an option.

  • You can start with just less saccharose instead of no saccharose. If you use, say, 500 g saccharose in 18 litres of water, you might get something which is better balanced.

• The beer will be darker, because it contains twice the amount of colouring materials. This isn't as serious as the bitterness, and obviously you can work around it by using lighter-coloured worts. If you buy plain malt extract, you should look for “pale malt extract”, but that's not always easy to find even at home brew shops.

Modifying the flavour

Extracting the sugars from malt is a complicated process; a full mash can take several hours. But there is a class of malt, called crystal malt, which doesn't need this process. The sugars in crystal malt are already in a water-soluble form, and you just need to soak it in warm water to extract the sugars.

Why should you want to do this? Crystal malts add body and aroma to a beer. You might find it interesting to experiment with a bland wort like “draught” and add the extract from some crystal malt (up to 10% of the total sugars) to the wort. The method:

• Buy 150 crystal malt from your local home brew shop and ensure it's crushed. Depending on what else you do, this will be about 4-5% of the total sugars. There are many kinds of crystal malt, varying from light to very dark. Since you need to buy this at a home brew shop, ask for advice there.
• Heat a litre or so of water to 60° in a saucepan.
• Add the crushed malt to the water, stir well several times over about 15 minutes.
• Separate the wort from the grain by pouring the contents of the saucepan though a sieve into another saucepan, squeezing the grains to get as much of the extract as possible.
• Bring the wort back to the boil! There are multiple ways to get a wort infection if you don't. Add the boiled wort to the other components.

The yeast

The yeast used to ferment a beer plays a large role in its character and flavour. Lager beers use one kind (fermenting round 10°), British-style ales use another (fermenting round 18°), and wheat beers use another (fermenting round 22°). There are also Belgian yeasts which are so different that I won't mention them further. Each of these yeast styles and their typical fermentation temperature is an integral part of the character of the beer. See the Wyeast Product List for more details.

The yeasts supplied with most home brew kits are anonymous:

About the only thing you know about them is that they are dried, and according to the instructions, they will ferment at up to 35° (left-hand sachet, from Coles) or 32° (right hand sachet, from Coopers). Looking at the Coopers yeast above, there is no indication of the kind of wort it is intended for, so I assume they supply the same yeast for all kits. The instructions that come with their “Real Ale” kit are titled “Original Series Instructions”, so I assume that it applies to their “lager” as well. There's no way to tell in the supermarket: unlike other kits, you need to destroy the lid to get at the yeast and the instructions. At least the Coopers instructions recommend a lower fermentation temperature, 21°—27°. The lower end of that range is acceptable for ale yeasts.

These details are causes for suspicion. It's not easy to dry yeast, and there's a very limited number on the market. They're chosen more for their ability to be dried than for their taste. Even these dried yeasts are never specified for fermentation temperatures of over 24°; only baker's yeast (which is not suitable for brewing beer) can handle such high temperatures. For this reason, I always throw away the sachets, and I used to recommend it on this page too; but to be honest, I don't know how bad the results are. I just don't want to risk a bad batch of beer to find out.

Affordable liquid yeast

So: where do you get a better yeast? The obvious place is your friendly home brew shop. There you will discover that a liquid yeast will typically cost you about $10, round about the same as the other ingredients put together.

This isn't as bad as it sounds. Yeast is not consumed by the fermentation process; on the contrary, it grows, and you can use the yeast left over at the end of the fermentation for the next brew. This is common practice in the brewing industry, and one of the parameters for yeasts is the number of times the yeast can be reused. In the Weihenstephan yeast strain characteristics document (in PDF format), you can read that the W 34 lager yeast (probably the world's most popular lager yeast) is good for 5 to 9 cycles, and that the W 68 wheat beer yeast is good for unlimited cycles.

Two main issues limit the number of cycles:

• The yeast characteristics can change slightly from one fermentation to the next. For example, they may become less flocculent, leaving a slightly cloudy beer.
• The effect of minor infections is additive, and after a number of fermentations the impurities will rise to a point where they have a negative effect on the beer.

The second issue is of more importance to home brewers. I find that I can reliably perform 3 yeast cycles, after which I throw the yeast away.

You don't need to wait until you do your first brew before re-using your yeast. Most serious home brewers will create starters and only use part of a yeast pack for a single brew. In this way, you can make up to 30 brews from a single yeast pack, reducing the cost to $0.35 per pack. See Starting with yeast starters by Phillipa Jarrett and Graham Sanders for details of how to do this. This article also describes other issues I've raised here.

Cultivating yeast from beer bottles

Another way of getting a good yeast, at least in Australia, is from bottle-conditioned beers, the most prominent of which are Coopers, who make a feature of the yeast in the bottle and thus include a lot of it. Here's what to do:

• Open a can of home brew concentrate and take out about a tablespoon of the syrup and put into a clean saucepan. Cover the can with the plastic cover and place in the fridge for later use. Add about 250 ml of water and bring to the boil, being careful not to char the syrup. It's normal for a lot of flakes to develop. Cool it to room temperature and put it into a scrupulously well-cleaned and disinfected glass bottle of about 1 litre. It helps if it's colourless glass.

• Cool and pour the Pale Ale, being careful to leave the yeast sediment behind. Drink the beer. (No, this isn't a Turkey with Whisky recipe).

• Shake up the sediment in the Coopers bottles and put into the bottle with the wort. Close again, shake well to dissolve the oxygen in the air (the yeast needs this to grow) and leave for a day. You should see some fermentation activity (brownish foam develops on the surface). Open from time to time to let off the pressure; otherwise it's (barely) possible that the jar might burst. If it doesn't develop within two days, you'll need to restart: don't continue until you get this far.

  Note that I mentioned Coopers Pale Ale. You should be able to use any other bottle-conditioned beer (i.e. one with live yeast at the bottom), though for some reason, Coopers Sparkling Ale doesn't seem to work as well. Some people say that the yeast there is dead, but I don't believe that's the case.

My understanding is that all beer sold in the USA is pasteurized, which kills the yeast,so this method will not work in the USA.

Hops

The hop extract in kits is all hop oil. This handles the bittering component well, but there's little aroma. You can help here by making a “hop tea":

• Buy some aroma hops such as East Kent Goldings (for English style beers), Hallertau, Tettnang or Saaz (for lagers), or Cascade (for US-style beers). For a 23 litre brew you'll need about 15 g. Again, your home brew shop can make a recommendation.
• Boil them in 5 litres of water for 10 minutes. Remove the hops with a sieve, bring back to the boil, then cool down before adding to the wort.

What do you think of this page?

This page and its companion get a lot of hits on my web site. I'd be very interested to hear what you think of them. I welcome feedback via email.