Home Grain Roasting

by Graham Sanders

and

Steve Lacey

WHY?

Up in the wilds of Nth Queensland tropical fruits just abound, but not a malt house within cooee.  In the early days of brewing you were lucky to get even Schnooner malt.  And when you did, it was about as fresh as a maggot- riddled roo. This is where I first started my experimentation.  A quick roast of these grains in the oven brought the stalest grains at least some respectability.

Over the years things improved and crystal malt started turning up, as well as fresh Schnooner malt. All well and good, but our crystal was (and still is to this day) unknown in spec and colour.  Nowadays you can get a fairly good range, though its near impossible to get speciality grains like Special B, smoked malt or brown malt, and the supply of the rest is at best inconsistent.

So for me, home roasting was borne out of necessity. But it also has one benefit that many craftbrewers really overlook.  Its like buying freshly baked bread and day old bread, you CAN taste the difference. So whether you have difficulties accessing roasted malts or you just want to try and add that special touch to your beers, you may find that you really want to have a crack at home roasting some malt.

WHAT EQUIPMENT DO YOU NEED?

Just an oven, oven thermometer, and cooking trays.  Now you could buy a mercury glass thermometer that goes up to 300 °C, but there is a far cheaper option. Go into one of those cooking shops and look for a flat metal oven thermometer.  They may not be very precise, but they are good enough for the job in hand, and are reasonably cheap. You can handle them hot, drop them, throw them in anger, ideal.

You also need a tray for the grain.  Anything that can hold a layer about an inch thick will be ideal.  Line it with aluminium foil if it is a bit grubby.

"Why the thermometer?" you ask. "I have a you-beaut oven where I can dial in the temperature, the local radio station and even pick up the police band".  Well those dials are seldom accurate and the sensor is actually on the wall of the oven, not on the grain.  You need to take the temperature at the grain surface.  That's where these metal ones are great too. You can sit them on top of your grain, and look through the window of your oven at the temperature of the grain.

Get to know your oven, you need to know what it actually does. Set your tray roughly in the middle and set the dial at 100c.  See what temp it flattens out at, do it again at at say 150c and so on.  See what temp variations occur.  And see how different tray levels affect the temperature.

So what are you after.  Two things. 1. You need to know what to actually dial in on the dial on the oven for a given temp. 2. You need minimum variations in temp.  A lot of ovens have so called 'hot spots' these are to be avoided.  Normally set your tray(s) near the middle of the oven.

Now what happens in a malting house is really quite a simple operation. Basically once the barley has germinated one of two things will happen:

1.        The barley is dried and then roasted.  The longer you roast it, and the hotter the temperature, well the darker the grain.  These are your basic malts. In order of darkness these are pilsener, pale, Vienna, Munich, amber, biscuit, brown, chocolate, dark (or similar names); or

2.        The barley is left wet and roasted.  Again the longer and hotter you do it, the darker you get.  These are your caramel malts. Again in order of increasing darkness: carapils, caravienna, caraMunich, various crystals, special B.

There are a couple of other variations.  Smoke the grain, and you get rauch malt, roast raw barley will add different flavours again. Roast it until its black and you have the roast barley for stout.  And why stop at barley, what's wrong with wheat, or rye? The options are endless.

But lets look at the general malts.  They all basically start from the one base malt, pilsner and carapils. Its what the maltster does afterwards that determines the final product. So you can take a carapils and make a Belgian special B if you know how to work it.  But you can also use a cara-Munich and make a special B.  In fact, as long as you go "up the line", you can make any malt out of a lighter one. So what malts do I have at home that I need. I can get pilsener malt, both imported and local. This isn't cheap, even if you buy it in bulk, and is specially favoured for those pale continental lagers. So I keep it for my use. Next is pale malt (usually Schooner). Now this is the mega-brewery malt that is mass produced.  It's not as good as pilsener malt, I believe it's a bit dextrinous, but well modified, cheap and readily available. This is my malt of choice for ordinary roast malts.  I have no trouble using it right up to chocolate.

For caramel malts I use a dark carapils (or very light cara Vienna, take your pick).  I go with a slightly dark carapils to ensure I have that caramel flavour there.  From this I have no trouble making all my caramel malts, even Belgian Special B.

So what are the methods we can use to roast our grain. One method, that I don't favour is "short and sharp"  This method you give a relative high amount of heat for a short period of time.  This works fine, roasts the grain very quickly. But I hate it because it doesn't really copy what goes on in a malting house, it doesn't give an even result, its too easy to muck up, and you have to almost constantly stir it to avoid hot spots and burning. BUT, it does allow you in an emergency to get some roasted grain quickly. Now this is worth trying when you have nothing to do, but I'm not going to cover it.

STEP BY STEP

There's nothing hard about it really.  All you do is dial in the desired temperature and let the oven heat up.  In the mean time spread the grain about an inch thick in the tray. Don't overload. Do multiple batches rather than make a thicker grain layer. Put the thermometer on top of the grain and put it in the oven. It will take about twenty minutes (depending on oven) to get the grain to temp. DON’T start the timer until all the grain is to temperature. Give it a quick stir and start the timer.

All you have to do now is stir it every half hour until done. No rocket science so far.  If you are using more than one tray, its also a good idea to rotate them as well. So what are the grains, times and temps.  This will take some experimenting depending on your oven, but to work it out all you do is get some commercial examples to compare it against (if you can). You will be actually be surprised how close you can get.  But what do you do if there are no examples.  Well you follow roughly the temperatures the malting houses use.

If you are singularly uninqusitive and want to copy what somebody else does, then I'll tell you the temperatures I use.

For raw roasted barley I like 45 minutes at 190c, followed by 30 minutes at 230c., or until 10% of grains are very dark, and 10 % is light brown. You will notice that time become flexible as it gets warmer.  That's because at the lower temp you may not see much changes going on, but its there.  As it get warmer you will see the changes happen quite rapidly, and you can actually determine the colour of your malt.  So if you recipe has a lot of dark adjuncts already, well you lighten your roasted malt.  And of course if its light on in colour, well you can darken it as well.  This is great for recipe formulation.

There is a trick to get those nice melanoidins in Vienna and Munich malts.  I have found that if the grain is slightly wet about an hour before hand, that some of the sugars are dissolved on the surface.  During the kilning it dries out again, but the wetting helps gives that extra colour, but more importantly better melanoid development. For rauch malt I also wet the grain a little more and I smoke it under a hot smoke.  The smoke flavour absorbed is far more complex and intense (so I can use far less).

Now what do you do with the caramel malts? Well if you wet them slightly you maintain that caramel edge, so you can make your cara-Vienna, cara Munich and Belgian special B.  Roast them without wetting them and you get a very nice crystal substitute.

Now a final tip. I always roast my grains the night before I use them.  Its this fresh bread syndrome. Fresher the better. I do make an exception with my "head hunting'' Rauch malt.  I let it air for a few weeks to let some of the more volatile compounds get away. Makes a smoother malt. There is also a counter opinion out there that suggests you need to let all home roasted malt "rest" for a week or two to "mellow" out. Needless to say, I don't subscribe to this theory, but in fairness, you should realise that some people believe it and you should be free to make up your own mind.

Well that's about it.

Shout

Graham Sanders & Steve Lacey