Brewing with malt extract

Dry or liquid extract

• Liquid extract (syrup, in a tin or a tub) contains about 20% water. It is cheaper per kilo but oxidises and darkens with time: buy it fresh.
• Dry extract (powder) keeps a long time in a dry place, is easy to measure and gives paler beers. It gets sticky in steam: pour it in off the heat while stirring.
• For 20 litres at a gravity of 1.050 to 1.055, allow about 3 kg of dry extract or 3.5 kg of liquid extract. The estimated original gravity calculator works out the quantity for your volume and target gravity.

Choose an unhopped extract, preferably a light one: the colour and character will come from the specialty grains and the hops, which you choose.

The equipment you need

• A 15 to 20 litre stainless steel pot, on a hob or a camping stove. A smaller pot also works, by boiling a more concentrated wort.
• A grain bag or a sieve if you steep specialty malts.
• A thermometer, and something to cool with: a sink filled with iced water or an immersion chiller.
• The equipment common to all methods: fermenter, hydrometer, sanitiser, bottles.

The concentrated boil

Without a big pot, you boil only part of the volume, for example 10 to 12 litres, with part of the extract, then top up with cold water in the fermenter. Two consequences to know:

• Hops give less bitterness in a dense wort: the IBU calculator takes this into account if you enter the volume and gravity of the boil, not those of the fermenter.
• Extract darkens as it boils (Maillard reaction). Add a third of the extract at the start of the boil, for the bittering hops, and the rest in the last 15 minutes.

Brew day, step by step

Steep the specialty grains

If the recipe contains any (crystal malt, chocolate malt, roasted malt), put them crushed in a bag and leave them for 30 minutes in 8 to 10 litres of water between 65 and 70 °C, like a tea bag. Remove the bag without squeezing it hard. This is not a mash: these malts need no conversion, they bring colour and flavour. Base malts (pilsner, pale ale), on the other hand, must be mashed.

Bring to the boil with the extract

Off the heat, dissolve a third of the extract, then bring to the boil. Watch the first minutes: the foam easily boils over. Turn the heat down as soon as it rises.

Add the hops

A boil usually lasts 60 minutes. The bittering hops go in at the start, the aroma hops in the last 10 to 15 minutes, and any late hops off the heat. The boil schedule gives the time of each addition, and the beer colour (EBC) calculator the expected colour for your malts.

Add the rest of the extract

In the last 15 minutes, turn off the heat, dissolve the rest of the extract while stirring, then return to the boil.

Cool

Put the covered pot in a sink of iced water, changing the water, or use an immersion chiller. A wort cooled quickly stays clearer and is less likely to be contaminated. At around 30 to 40 °C, pour it into the sanitised fermenter.

Top up, measure, pitch

Top up with cold water to the target volume, pouring from a height to aerate. Aim for 18 to 20 °C before the yeast; mixing hot and cold water helps you hit the temperature. Measure the original gravity. If it is off target, adjust the gravity gives the water or extract to add. Pitch the yeast and close with the airlock.

After brew day

Fermentation and bottling are the same as for every method.

Common extract mistakes

• Pouring the extract in over the heat: it sticks and caramelises at the bottom of the pot.
• Boiling all the extract for 60 minutes in a concentrated boil: the planned blonde comes out amber.
• Calculating the bitterness with the fermenter volume when the hops boiled in a wort twice as concentrated.
• Steeping specialty malts above 75 °C: they release astringent tannins.

Going further: partial mash

Between extract and all grain, a partial mash replaces part of the extract with 1 to 2 kg of base malt mashed in the pot, with a bag. It is the same technique as BIAB, on a smaller scale, and a good way to try mashing without changing equipment.