What does the term "knockout" refer to in brewing?

The term "knockout" in brewing specifically refers to the point when the heat is turned off on the boil kettle at the end of the boiling process. This is a critical step in the brewing process as it signifies that the wort has been boiled for the necessary time to extract flavors from the hops and to sanitize it, thereby making it ready for cooling. Once the heat is off, brewers can proceed to cool the wort and then transfer it to the fermentation vessel to add yeast, marking the transition to the fermentation phase.

While fermentation starting, the addition of hops, and cooling the wort are important aspects of the brewing process, they do not accurately describe the "knockout" term in the context of brewing terminology. Understanding this definition helps clarify the significant stages of brewing and how different processes are delineated.