Does anyone have experience with fly sparging and sparge water temps? I have been fly sparging for a couple of weeks and found that the sparge water needed to be about 177 degrees to maintain an ambient grain bed temperature of about 155 degrees. Does this make sense? Should the grain bed maintain the initial rest temps throughout the entire sparge?
If you’re fly sparging you should probably do a mash out. Add enough boiling water to your mash at the end to raise it to about 168. After that, you can sparge with 168f water to maintain that temp. Not stopping the enzyme activity can result in a sugar profile you may not have intended.
There’s a pretty lengthy discussion going under the heading of Batch Sparge, too. The discussion touches on both batch and fly sparging. The one thing everyone seems to agree on is getting the mash temp up towards the 170 range to denature the enzymes and stop conversion.
For a very, very detailed explanation you can visit Braukaiser.com - German brewing and more. Just google it; you’ll find it.