WHAT IS MALT?
Malt: "the soul of beer" has a history dating back 4,000 years. Crafted from cereal grain barley, it is steeped, germinated and kilned to become malt. One of four essential ingredients used in producing craft beer, malt provides color, aroma, flavor and body to every ale and lager. It is also the source of fermentable sugars which become available in the brewer’s mashing process and later converted to alcohol during the fermentation process. Brewers use malt crafted from Barley, Wheat, Rye and other specialty grains.
HOW IS IT MADE?
Malt is made from cereal grains including Barley, Wheat, Rye and other specialty grains. Three simple process steps are followed in creating craft malt:
The first and very critical step in creating quality malt is where the grain kernel is cleaned and brought to life with the aid of water and oxygen. This is done by immersing or “steeping” the grain in water for a period of time followed by an air rest period that allows the water content of the grain to increase to a controlled level beyond 40%. Water temperature and aeration are critical control parameters for high quality malt. The steeping process can vary with grain type and size but typically occurs over a 1-2 days.
The second step is where the growth and modification of the grain occurs. From the outside of the grain, rootlets emerge from the kernel and within the outer husk the shoot or acrospires grows. Inside the grain, modifications take place to activate enzymes which serve as catalyst that enable the conversion of starches to fermentable sugars.
To achieve a high quality and consistent germination process, it’s important to control temperature (14-18 °C) and moisture levels with regulated air flow and uniform water spray. To avoiding grain clumping, non-uniform heating and varying rates of germination, grains are separated with periodic rotation. Even with modern equipment and structured approach, the degree of modification is still gauged today by the craft malster with his eyes, his sense of smell and with his hands. The germination process typically occurs over a 4-6 days and results in what is termed “Green Malt”
The third and final step in the malting process is kilning. This convection heat treatment step initially dries the green malt which prevents further germination. For most malts, moisture is initially removed from the germinated grain reducing it from greater than 40% to less than 12%. Additional drying further reduces the moisture content and prepares the malt for flavor and color development. Other important results achieved during the kilning process include enzymatic activity and friability. It is the controlled variations in this step that produce the wide range of malt colors and flavors used by brewers in crafting their unique and distinctive ales and lagers.