Malt is not so much a thing as it is a process, by this I mean essentially malt is another name for a toasted cereal grain. Barley, Wheat, Oats, Rye and Sorghum are all classified as ‘malts’. At this point you may be asking ‘Why do they toast the grain?’ this is done to unlock the basic sugars and enzymes that are essential in the brewing process, we’ll go into exactly what these are and how they work later on. To kick off this ‘malting process’ all you really need in water and after hydrating the seed it will begin to sprout usually after a couple of days when placed into a warm environment.
This in turn sets off a chain reaction that ultimately leads to the production of proteins called Amylases. The seed is created with the amino acids necessary to create Amylase. Therefore, this whole genetic sequence is unlocked when water is introduced into the seed. So what is Amylase consist of then? Amylase is classed as a enzyme because its main objective is to initiate a biological process where in turn it turns those cell blocks into starch compounds, the main goal of starch is to provide a food source for the developing plant, a kind of food storage facility as it were. This is where Amylase comes in, it converts the starch into simpler sugars that can be consumed by the plant such as maltose and glucose. After several days of moisture, a very thin shoot will start to develop as well as the acrospire, which is the part of the plant that we see above ground.
General rule of thumb for most maltsters is as soon as the acrospire is the same length as the seed, it is time to start the kilning process. Kilning the malt is as diverse as it is complex, in some parts of the world the malt is put into a large kilning oven and set to around 65C. Alternatively in other locations it is rested on a large floor for hot air to pass through small holes. It is very important to kiln at a specific temperature or your are in danger of denaturing the enzymes required for the malts diastatic power. Diastatic Power is the term used by maltsters to describe the malts ability to covert starch into simple sugars, this is a essential component of brewing as the amylase must convert the sugars for the yeast to consume in order to produce alcohol and Co2.
Liquid Malt Extract (LME for short) is concentrated form of malt that comes in the form of a thick treacle-like syrup, this is made by a vacuum heating procedure and compressed using a centrifugal machine. Dry Malt Extract (DME) in contrast is has the consistency of flour and is basically just LME put through a spraymalt procedure. Both of these have their advantages and disadvantages, some brewers prefer to work only with LME because they believe it produces the greatest results. It also requires one fewer processing step, making it desirable to those who prefer the most natural form of product. It is, however, extremely sticky, making it more difficult to deal with and having a shorter shelf life. Some people believe DME produces similar results, being just 2% water as opposed to 20% for LME it has a much longer shelf life and doesn’t have a darkening effect over time that tends to affect LME.
Weighing DME is also a much easier procedure. Brewers Malt can be separated into three catagories: Base malts, which are primarily used to create starches for the yeast to feast on. This of course is determined by its Diastatic Power which we covered earlier on, there are a vast variety of base malts available and choosing the right one is key. For example, if you are looking at making a lighter beer (ie: pilsner, pale ale etc.) you might want to consider using Pilsner, Pale or even Maris Otter as a base malt. These malts are only lightly kilned which means a higher diastatic power is available but is more susceptible to DMS (Dimethyl Sulphide) which can leave the beer with a slight corn or boiled cabbage-like taste.
Specialty malts or Roasted malts as they are also referred to as on the other hand are more geared towards adding flavour and colour to your beer, they can vary anywhere from a subtle colour and flavour which can be extracted from a pale chocolate malt which can be used in bigger amounts if your brewing porters or stouts or even in smaller amounts if you’re creating a Amber or Red Ale for example. Next, we have the chocolate malts such as Roasted Barley and Carafa I which is roughly around 300 Lavabond. Roasted Barley is especially apt for Russian Imperial Stouts to give it that robust smokey characteristic. Following from, we have Black Malts which are interchangeable with Roasted Barley and sit around the 450 Lavabond range such as Black Malt and Carafa II.
Finally, we have the Carafa range malts, Carafa III comes in at around 600 Lavabond and is used in small amounts in such beers as Schwarzbeirs. It pays to be sparing with these latter malts as they can add some astringency to the finished beer. Finally, we come to Crystal or Caramel malts sometimes called stewed malts. Crystal malts go through the germination process just like base malts do, but here is where the two malts part ways. Unlike base malts, crystal malts are not dried out.
Instead, they go straight into a kilning process in a kilning drum. They are then put into a warming system which leave a high volume of moisture trapped in the malt. The heat is then ramped to to roughly 150C, the longer the crystal malt goes through this heating procedure will determine the type of colour malt. Light Crystal, Medium, dark and so forth. Caramalization can occur very rapidly and so the maltsters need to be adept at know exactly when to terminate the procedure. There are several types of crystal/caramel malts
- Dextrin malts – These crystal malts differ from other malts as they are taken out of the roasting drum at around 90C, which in turn will leave the end result with little in terms of flavour due to the fact that the main enzyme retained are dextrins themselves.
- Carapils – Also known as Crystal 10L, containing the same amount of dextrin as dextrin malt. It will imply a sweet, almost honey-like flavour to the beer.
- Biscuit malt – The name speaks for itself; it gives the beer a biscuity/bready flavour and aroma.
- CaraFoam malt- This crystal malt is used for head retention.
- CaraRed/Melanoidin malt – This crystal malt is used to impart a reddish hue to ales and less frequently lagers.
- CaraBohemian malt – A Weyerman crystal malt used to produce a golden hue, especially when paired with Vienna or pale malt.
- CaraAroma malt – Used to push a fruity/estery aroma throughout the beer.
So, what are the advantages of using Crystal/Caramel malts? the first thing that comes to mind is that crystal/caramel malts have a tendency to lower your mash pH.
Another advantage is the addition of a more complex flavour capability.