In general, modification refers to the extent to which the endosperm breaks down. During the malting process, enzymes break down the cell structure of the endosperm, releasing nutrients necessary for yeast growth and making the starch available for enzyme degradation during mashing. Modification of the endosperm correlates with growth of the acrospire. As the acrospire grows, chemical changes are triggered that result in the production of numerous enzymes, which are organic catalysts. Their function is to break down the complex starches and proteins of the grain.
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