When the malt is crushed too coarsely, improperly or inadequately, it will cause a decrease in the quality of wort and loss of leachate.
In malt with insufficient or uneven dissolution, especially in the tip part of the malt with insufficient dissolution (the dissolution inside the grain starts from the germ and gradually progresses to the tip), the contents are hard. Such hard malt is difficult to crush, and the resulting crushed malt is likely to be coarser than the well-dissolved malt, resulting in the enzymes in the cells not functioning adequately.
The coarseness of crushed malt, the components not only differ in appearance, but also in the composition of the wort made into semi-finished products, mainly in terms of solubility, leachate and leaching rate during saccharification.
It is proved that the better the quality of malt crushing and the appropriate degree of crushing, the less residual leachables in the final wort component, the higher the yield and the good quality of wort, because the well-solubilized malt is more brittle and easy to crush, they are rich in enzymes, easy to be penetrated and decomposed by enzymes, and the crushed malt fines and powders are already partly water-soluble substances, or very easy to be decomposed by the action of enzymes during saccharification. On the contrary, poorly dissolved malt, the particles are unevenly soft and hard, the enzyme content is relatively small, and the particle size control of crushing is not uniform, especially the hard parts may appear relatively coarse particle size, which causes the enzyme action to be hindered, and the enzymatic decomposition and dissolution of the saccharification process is difficult, slow or incomplete, and it is easy to cause unreasonable wort components and loss of leachate.
The proportion of coarse grains in crushed malt is, to a certain extent, determined by the solubility of malt, i.e. the worse the dissolved malt is, the less easy it is to crush. From the above, it can be seen that the process of malt saccharification, speed, leachate, leaching rate, etc. also depend on the state of crushed malt.
The coarse, hard and insoluble coarse components are moderately crushed again to improve the yield by about 1.5-2.4%; the increase may be even greater for poorly dissolved malt. This can also prove from the side, no matter what kind of quality of malt, the degree of crushing, crushing quality is a very important aspect.
Although the malt is finely crushed, the dissolution of substances in the endosperm and the release of enzymes are accelerated, and the released enzymes can act better in the best temperature range with the fastest speed, it can improve the decomposition of the contents, increase the content of fermentable sugars, make the saccharification reach the end of iodine reaction in advance, and shorten the saccharification time, but this is likely to cause difficulties in production filtration, and the same will cause problems in product quality and leaching rate. Therefore, the quality of malt and the degree of malt crushing directly affect the process of production and the composition of wort quality.
These examples show that the yield of malt saccharification decreases with the increase of the proportion of coarse meal (if no special measures are taken in saccharification); on the other hand, for malt with very poor biochemical dissolution, the malt must be carefully crushed to achieve a high leaching rate; the lack of malt quality can be compensated to some extent by the crushing process; the worse the malt dissolution is, the more important the quality of crushing is.
In short, in order to make the contents of the malt more susceptible to enzymatic action, the degree of crushing is a key step in stepping into saccharification.