wort near boil while sparging

hey everyone.

So I hear alot about people taking the 1st runnings from the mash and keeping it at a near boil while sparging.

Well, I don't know how everyone's protocol runs, but I know I can take up to 30-45min to sparge. How much water do you think is lost from the 1st runnings when kept at a near boil for 30mins? Do people compensate for that water loss beforehand?

I've never done that. I simply heat my first batch of sparge water while I'm collecting the runnings of the mash, then when that batch is sitting in the tun for 10 minutes I heat the second batch. I'm using a Bayou Classic propane burner, so that may speed things up a bit from what you're using if you're on electric.

nah I am using propane. I fly sparge so it takes a while since water is being added very slowly. I just worry if I tried to keep my 1st runnings heated I would lose too much volume and not hit my target batch size. Then again, I guess the sugar would still be there and I would use water post boil to bring the volume to my desired size.

Funny.... I was just dealing with this last weekend. I usually fly sparge but decided to try a batch this time just to compare. (10 gal batch)

As soon as I have a couple gallons of the first sparge, I put the boots to the banjo. By the time I get the 1st strike water into the grain and stirred up, the kettle is boiling. I let his sparge sit for 15 mins so the 1st pull boils hard for 15-ish mins.

Transfer the next to the boil which, of course, kills the boil. By the time I've added and stirred the 2rd strike to the grains, the boiler is going again.

I let this last grain-soak go for about 10 mins (cuz I was impatient) and transfered it over with the rest of the boil. I was a little short of my target boil volume, which was 12 gals, so I ran some more strike thru the grain and pulled it over to the boil almost immediately.

Once it was ALL over and again at full boil, I waited for the last break and then started my hop schedule.

Notes: Every time the boil started (or restarted) I had crazy boilover risks. Even with the initial sparge! So one negative was someone has to watch for three times as many possible boil-overs!

I think the positive aspect of this method is that you boil off more total volume which allows you to sparge more with no extra process time!

No effect on the hop schedule, but may darken your brew some from that first hard, low volume boil.

BTW: Best efficiency I have ever had.

Other effects?

As a batch sparger here...can you even call it 'first runnings' when fly sparging since its a continuous sparge..there is no 'first or second' ...just 'runnings' as a whole.

It'd def depend on how close to boiling we are talking. 200F? 190F? 209.7F? The closer to boil the more evaporation is my guess.

Like Duffer, I start boiling as soon as I have my first runnings. I also do a 90 minute boil after I get my last runnings so the first runnings might boil for two hours. I boil with two pots and two turkey fryers, also. When I can pour both pots together and it is about 4" below full, it will fit in the fermentor.

The hops are added during the last hour except sometimes I first wort hop, too.

I start heating the kettle when it's about half full, which normally gets it almost boiling by the time runoff is done. My perfect scenario is starting to boil just as I close the runoff valve on the MLT.

I start the burner under the pot when there's a few inches of first runnings in there. It's around 180F by the time the first runnings are reduced to a trickle. I throw in the 170F sparge water, stir, and then let the second runnings drain. Just about the time I've gotten all that can be reasonably collected, the pot is going over 200F, about ready to boil. Works out pretty well. I'm strictly thin mash / one sparge. Not all that interested in hitting those magical 140% efficiencies, more just K.I.S.S. brewing.