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Wort Volume

TroubleShooting

Thomas A. Adamczak • Grand Rapids, Michigan asks,
Q

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.

A
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.