I was at a club meeting over the weekend and there were some Learn To Homebrew demos. The All Grain demo make me think about when one should stop collecting 2nd runnings. I batch sparge and at some point, when the 2nd runnings are slowing down, and I’ve collected enough wort I will stop collecting. I know that after a point the runnings are mostly undesirable (tannins). I’ve gone to the refractometer to check gravity, but just guess when it’s time to stop collecting. How else does anyone else gauge when to stop collecting? Just curious if more people are intuitive, or technical about when to stop collecting?
When I hit my boil volume.
Ideally, with batch sparging you’d want the tun to run dry exactly as you hit your pre-boil volume target, with no wort left behind. That would maximize your efficiency.
+1 for the boil volume. I usually leave some wort behind, which probably accounts for part of my poor efficiency. My next brew, I plan to wait on heating my sparge water until I have already done my initial runoff, so I know exactly how much I need to hit my boil volume. So my answer might soon be “when it’s dry.” I guess I will see how it turns out.
+1 on that.
I don’t stress about it too much, but along the way at various stages I taste an ounce or so of what’s going into the collection buckets bound for the boil. Only a few times have I stopped collecting (based on the taste) and at that point just topped up with water to boil volume. My palate is pretty sensitive to the dry, tannic stuff that comes out and I can usually tell when the sugars in the mash are really spent. This method hasn’t let me down yet. I guess it’ll be fine as long as these old tastebuds hold out!
I don’t need to do stop the sparge very often, though, if I’m collecting my usual 6.2 gallons for a 1 hour boil (to yield 5.12 gal). Any more than that (like 6.5 to 7gal for a 90 minute or longer boil), I’ll stop and top it up with carbon filtered water.
I should add that with time, you get to know your system and how much water you need for how much grain you are using. To the point that you have very little water left in the MT.
I agree. I drain every last drop. I even lift the cooler vertical to get every last drop out of the drain. If my pre-boil volume is too high, then that’s my own fault and I boil a little longer to compensate and don’t add as much water next time.
Thanks for the replies. So is this generally more of a concern with fly sparging (when to stop collecting)? I tend to try to collect almost everything and stop when I reach boil volume as well. Determining the sparge water amount seems to be where I use intuition more and judge the size of the grist and how much I’ll lose in the tun.
As a10t2 and DMTaylo2 said, this:[quote=“Haasfilm”]I know that after a point the runnings are mostly undesirable[/quote]
and these:[quote=“The Professor”][quote=“Nighthawk”]When I hit my boil volume.[/quote] I taste an ounce or so of what’s going into the collection buckets bound for the boil. Only a few times have I stopped collecting (based on the taste) and at that point just topped up with water to boil volume. My palate is pretty sensitive to the dry, tannic stuff that comes out and I can usually tell when the sugars in the mash are really spent.[/quote]
only apply to fly sparging, not batch sparging.
There’s no need for this to be a guess. The amount of water absorbed by the grain is known, so you can just heat up:
pre-boil kettle volume + (pounds of grain x 0.12 gallons) + dead volume
or, you could use Denny’s method and measure the volume of your first runnings and add the volume that would bring that up to your pre-boil kettle volume.
Thanks again for all the replies. “Batching spargers”? Oops.
I believe the gerneral consensus is 2brix.
True, but when batch sparging you’ll never get there.
Determining sparge water amount is easy. After you drain the mash, measure how much you have in the kettle. Subtract that from the amount you want to boil. The answer you get is how much sparge water to use. Since the grain is already saturated from the mash there will be no further absorption. That way you won’t end up with anything left in the tun.