In the mash, brewers need to get the starch-degrading enzymes (amylase enzymes) to reduce the large molecules of amylose and amylopectin into mixture of fermentable carbohydrates (esp. the sugar maltose) and non-fermentable carbohydrates. In order for this to occur, the starch needs to be dissolved in water hot enough to dissolve it. This step is call gelatinization, even though gelation might be a more appropriate term. (When starch is dissolved in water, it would be more appropriate to describe the result as a gel. Gelatin is an animal product, formed from collagen.) However, the term “gelatinization” is firmly entrenched in the brewing literature, so I’ll use it here.
Much of the (fairly) recent scientific work on barley starch should be of interest to advanced homebrewers or homebrewers with an interest in biology. This post is an introduction to a series of articles that will review what modern science has revealed about barley starch. Recently, I posted a series of articles on enzymes for brewers. Although it dealt with all brewing-relevant enzymes, not just starch-degrading enzymes, you can look at these starch articles as covering a lot of the same or similar ground, but from the perspective of the substrate, not the enzymes. (There will also be a few new enzyme-related topics, as well)
In this article, I will give an overview of the subject. In the subsequent articles, I will fill in all the details. In the individual articles, I will try to explain the topics so that you don’t need an extensive background in biology or chemistry to understand them.