What happens to the enzymes after the grains are heated during the malting process?

During the malting process, when grains such as barley are heated, the enzymes that were activated during germination are deactivated. This step, typically occurring during the kilning phase, is crucial as it stops the germination process at the right moment, preserving the desired levels of enzymes that are essential for converting starches into sugars during mashing.

Once the grains are heated, the temperatures reached are sufficient to denature these enzymes, meaning they lose their structural integrity and functional ability. This is important because while these enzymes are necessary for the conversion of starches to sugars in the brewing process, they must not remain active after the malting process to avoid unintended further enzymatic activity during storage.

While it might be tempting to think that the enzymes could remain active indefinitely, their function essentially ceases after they are exposed to heat during kilning. The heat treatment ensures that the malt can later be processed without any risk of excessive sugar conversion occurring outside of the controlled mashing environment. Overall, option C accurately describes the effect of heat on the enzymes during the malting process.