So I'm making a partial mash today, and I added 2 gallons 162* water to 3.5 lbs of grain. I came back 30 minutes later, and it was still at 160*. I added some water and got it down to about 154*, but I'm wondering if that 30 minutes destroyed the enzymes and thus make the 154* rest pointless, or if I'll actually get some benefit out of the 154* rest?