Milling malt with the professional way is essential to the beer brewing process. The main purpose of milling is to reduce the malt grains to smaller particles in preparation for mashing. Prior to milling, the malt has a starchy endosperm hidden under the outer shell of the malt. All these starches need to be broken down and exposed in order to extract all the sugars into the wort. Milling can be done either by dry or wet methods. Let's dive into the milling guide to learn more about this process.

Dry milling
Dry milling is the most common milling process used by breweries. In this process, milling relies primarily on roller mills, which vary in complexity. There are different types of malt mills with two, four, five or six rollers and a series of sieves that vibrate to crush and segregate the grain particles.

The finer the malt is crushed, the faster and more complete the dissolution of its contents, the easier the chemical and enzymatic reactions, and the better the collection rate. The malt should not be pulverized too much, and the malt can form a natural filtering layer. If the malt is crushed too finely, it will reduce the filtration performance of the wort and increase the difficulty of filtration. In terms of wort quality, the breakage of wheat peel should be as small as possible. This is because the hulls contain a series of other soluble substances that can enter the wort, such as malt polyphenols, bitter substances, silicates and proteins, in addition to cellulose, which is the main constituent. These substances can have a negative impact on both the color and taste of the beer after being strongly debrinked.

Wet milling
In wet milling, the malt is soaked in a large amount of warm water during the milling process. This is done to increase the moisture content of the malt to 15%. Compared to dry milling, this process ensures that pre-wetting not only reduces damage to the hull but also results in a larger volume of malt in the grinding tank.

Its disadvantage is that the hulls can be kept intact because the wet crushing pre-soaks the malt, which increases the toughness of the hulls. In this way, the lees layer in the filter tank is looser, which makes the wort filter faster and reduces the leaching of harmful ingredients from the hull without dust. In the case of malt pre-absorption d, it is easy to grind into pulpy fine grains, so that it is conducive to the pasting of grains, the freeing of enzymes and the dissolution of soluble components.

Anyway, malt and grains are crushed to dissolve well and the quality of crushing plays an important role in the biochemical changes of substances during saccharification, wort composition, wort filtration and raw material utilization.