I was wondering if anyone had any thoughts on how the water/grist ratio affects mash efficiency, and what the ideal ratio is. I've done mashes at 1qt/pound, and 1.25 qts per pound and found the mash extraction efficiency was higher at 1.25. Yesterday I did a mash with about 1.4 qts/pound, and my efficiency was off by about 10%. I've always used Maris Otter malt for my base malt; this time I wanted to branch out and used Weyerman's Pilsner malt. pH was at 5.2, which is about what it is always. Mash temp in the 150-155 as usual as well. Any ideas??
Yes it is timely of you to post on this subject! By mash efficiency you probably mean conversion efficiency and lauter efficiency combined. We call that pre-boil efficiency. See the chart in this FAQ for more details about the four definitions of efficiency we use at BF: http://www.brewersfriend.com/faq/#brewsessions5 I would think if mash thickness does impact efficiency, it targets conversion efficiency (The percentage of total available sugars that were extracted from the grains inside the mash tun). We feel it is important to distinguish between conversion efficiency and pre-boil efficiency. That way brewers know if the efficiency loss happened inside the mash tun, or was due to a less than perfect rinse of sugars from the grains (common to batch spargers like myself).
I get the opposite effect - thinner mashes (my standard is 1.8qt/lb) gets higher conversion for me. How long are you mashing for? 60 mins? 90 mins?
Kaiser pointed out a good lead to some studies that were done in the wiki in discussion in thread hicksbrewer pointed out. I've looked around and all I have seen to add to that is your brewing system will tell you which thickness is right for you. Experiment, as you are doing. Your system will tell you what is right for you. Also different grains and adjuncts will affect the appearing thickness as well. The consistent temp of the tun, how much you stir, if you recirculate with a RIMS, are just a few other factors that work with the efficiency. Kind of like grandma's apple pie. It tastes the best when she makes it in her kitchen. Also you can do a quick iodine test to check for conversion before you end your mash to verify your mashing long enough.
I'm assuming you can measure the gravity of the verlauf to give you a good estimate of the gravity before lautering? correct? Then remeasure the gravity after lautering to determine efficiency of mash/lauter. make sense? back to original issue though, I think my brewhouse efficiency was off because of the malt i used. Before this batch I've been using Maris Otter malt as my base; this time I used Weyerman Pilsner Malt. cool stuff nonetheless.
I take fully mixed measurements. As for the BHE, it comes down to the ppg of the grains, and they do vary year to year. If the recipe ppg and the real ppg are not in sync, the numbers will be off in either direction. We update the list when we are aware of differences between our list and what the malting companies publish.
yeah, that makes sense, I just don't know if weyerman would tell you "oh, by the way, if you want to get our PPG, you really need to do a Protein rest ( or a decoction)
Last month I used Weyerman Pilsner Malt for 82% of the grain bill in a lager, with a single rest step at 152F, and got 100% conversion no problem (38 ppg). All malts these days should be fully modified.
hrm... well, i checked the temp during sparge, and it was 145F. The sparge water was 170F in the hot liquor tank, and I've heard you shouldn't have it much above 168F or you'll leach tannins from the grain. But maybe the sparge temp was too low, and i left a bunch of sugars in my mash. I fly sparge, BTW.
