Beer Learning Centre
Brewing can be as simple as tossing a can of malt extract into water and adding yeast. However if you really want to pursue this craft you'll want to go deeper. This section of our website has articles and information that will help make you a better brewer.
Roasting pale malt
Sometimes you will come across a recipe that requires a malt that is not readily available. This is often true for older recipes that require brown or amber malt. These can easily be made in your own kitchen by roasting pale malt in your oven.
The roasting process
Line a large baking tin with aluminium foil, and pour in pale malt to a depth of 12 mm (1/2 inch). Place in the oven (preferably convection) at 100 C (230 F) for 45 minutes to dry out the malt, then raise the temperature to 150 C (300 F). After a further 20 minutes remove 6 or 7 corns from the tray, slice across the centre with a sharp knife and compare the colour of the starchy centre with that of a few pale malt corns. The pale malt is almost pure white; for pale amber the colour should be the palest buff, just noticeably different from the pale malt. Continue heating until this colour is obtained, usually about 30 minutes.
For amber malt, continue heating until the cut section is distinctly light buff, usually 45 to 50 minutes. If brown malt is needed, raise the temperature at this point to 175 C (350 F) and wait until the cut cross-section is a full buff, i.e. about the colour of the paler types of brown wrapping paper. When the correct colour has been reached, remove the tray from the oven, allow to cool and store the roast grain in an air-tight screw-top jar (large canning jars are ideal). If used soon after production, the flavour imparted by home-roasted grain is superior to bought grain.
The roasting times given above are intended only as a guide to producing the wanted roast grain Practical tests on the oven available will enable home-brewers to adjust the time and temperature to produce the colour needed.
Retaining diastatic activity
Roasting by the method above will most likely destroy the enzymes required for starch conversion. This is fine if you are intending to use your roasted grain for a small percentage of your grain bill. However if you intend to use a large amount of grain you will want to try to protect the enzymes to retain diastatic activity. You can do this by drying for a longer time at lower temperatures. This will produce a diastatic amber malt.
How to make a diastatic pale amber malt
Set the oven at 70-75 C (160-170 F) and put in the tray of grain (the grain bed can be a little deeper - up to 1.5 inches, say) and leave for 2 hours to dry out the grain. Raise the temperature to 88-94 C (190-200 F) for 30 mins then to 110-115 C (230-240 F) for a further 30 mins. Check the colour as above. If insufficient colour, then check at 15 min intervals. If after 1 hour at this temperature, colour has not been achieved, raise to 120-125 C (250-260 F) and continue to check at 15 min intervals. The resultant Pale Amber should be able to mash itself.