Ask Mr. Wizard

Wort Volume


Thomas A. Adamczak • Grand Rapids, Michigan asks,

I have been homebrewing for more than a year and a half. I’ve mainly been extract brewing with great results, but I have reached that point that every homebrewer has reached, or will reach: the need to move on to grain brewing. Almost every grain recipe (partial mash or all-grain) suggests bringing the volume of wort to six gallons before boiling, even if the runoff after sparging is less than six gallons. Typically in an extract batch I use two to three gallons of water to boil my wort, then add enough pre-boiled and cooled water to bring my volume to five gallons prior to pitching.

What effects could boiling an all-grain or partial mash wort at a volume of less than six gallons have on my overall batch if I were to add preboiled tap water to the wort (to five gallons) prior to pitching? It seems the pre-boiled, cooled water would help cool the wort quicker to pitching temperature.

This question really has more to do with sparging than it does with the volume of wort to boil. An all-grain brew begins with the mashing process. During mashing, starch is converted
Response by Ashton Lewis.