Beginners Guide: Malt
What is malt?
Malt is the life-force of beer. Without the malting process there would be no fermentable sugars for yeast to break down into alcohol and carbon dioxide. And without that we would not be able to make the brew we know and love.
Malt, by definition, is processed grain seeds modified from their natural state and although other cereals such as wheat may be used in the brewing process, barley is the favoured grain to make beer, though some others are added in sometimes, but we’ll save them for another day.
All malt begins life as barley in a field, before being harvested and taken to the maltings to continue its journey to your glass.
What goes on in the maltings?
Barley in its natural state contains starch that isn’t ready to be turned into alcohol by yeast, so the maltster (the technical name for someone who works malting barley!) harneses the process of germination — allowing the grain to partially sprout — in order to make the stored energy in the seed available. This process is called malting and it activates enzymes within the grain that begin to breakdown starches into simpler sugars which are accessible to yeast further along the brewing process.
The first step in making malt is to soak the barley in water for 40–48 hours during which the barley alternates from being fully submerged and drained until its moisture content is up to around 44%. It is this absorbed water that activates the natural enzymes that begin germination.
The next step is to allow the barley to continue germination. It is moved from steeping tanks to germination compartments where the enzymes break down protein and carbohydrates and open up the starch reserves required for brewing. Germination occurs over a 4–5 day period in which the barley is temperature controlled and turned regularly to prevent the grains growing together.
Finally brewers stop the germination process by heating up the grain in a kiln. Without this step the plant would simply continue to germinate and use up all the starch reserves required to make beer in order to grow.
Why not just use sugar?
Malt isn’t simply used as a means to an end; it also contributes to the finished brew. Not all of the sugars released during the malting process can be broken down by yeast so any sweetness in your beer originates from malt.
The amount of time heating the malt also has a huge effect on the colour of the beer brewed and its ultimate flavour. If the malt is lightly roasted the brewer will create a light, pale beer (perhaps a pilsner) however deeply roasted malts produce dark or black beers, such as a porter.
Each type of malt also brings its own particular set of flavours, similar to wine grapes malting barley is varietal and tastes different depending on the strain and terroir, and many beers will use a combination of different malts to achieve the desired colour and flavours.
Why should you care about malt?
Malt is the soul of the beer, providing your brews with all their base flavours, colours and mouth feel as well as allowing the production of alcohol. Cheers!
