Efficiency at higher mash temps - am I doing it right?

Last weekend, we brewed a clone of 21st Amendment’s Brew Free or Die IPA, using the recipe provided by Shaun Sullivan of 21st Amendment with the proportions adjusted
. The recipe calls for a single-infusion mash of 159 degrees for 60 minutes. We hit the mash temp exactly, but after sparging, ended up with a wort gravity that told us we were only 62% efficient. We used the exact same mash and sparge method we have in the past, which has given us over 80% efficiency on longer, lower-temp mashes.

Given that the whole point of a higher temp mash is to produce a less-fermentable but fuller-bodied wort, is it normal that we’d end up around 60% mash efficiency? With the 90-min boil, we’re still going to end up with only .5% less ABV in the final product, albiet we’ll also have to aim for a lower FG (1.010 vs. 1.015). Or do we need to work on our efficiency? Or do we need to do a two-step mash, given that we brew on a much smaller scale than 21st Amendment does?

Higher temps usually give you better conversion not worse. But 159 is super high. I personally would never go anywhere that high.

And I don’t think you will hit 1.010 with that high of a mash temp. But good luck.

Is 159 only a workable mash temp because 21st brews 450 gallon batches? It sounded high to me, too. Would 155 be a better target next time?

Sounds like as mistype to me. But I could be wrong. and yes I would think 153-155 would give you pretty of body.

Well, at least I also took the “aggressively pitched” direction at face value, so there’s plenty of top-cropped California Ale yeast in there from a previous session IPA. Hopefully it’ll get us close to our target FG.

159? That is crazy high for an IPA…more like a Scottish or even a Flanders mash temp.

I don’t recall BFOD being overly sweet or dextrinous.

Anyway, I don’t think mash temp should affect efficiency, more the TYPES of sugars that are in your wort. Mashing above 158 will give you more maltriose, dextrins and other long-chain carbs that yeast can’t metabolize, so you will get a sweeter finished product with more body.

Said differently, mashing higher will (should) affect your FINISHING gravity way more than your STARTING or pre boil gravity. I’m thinking if your temperature was actually 159*, you are going to have a real hard time getting this down to 1.010.

I’m thinking it was something else that negatively affected your efficiency. What was your grist:water ratio? Also, it sounds like you had success in the past with a longer mash. 21A probably does a 60 minute mash because they have an incredibly efficient mashing system.

We went with 1.5 quarts/lb of grain. Our grain bill was 11# 2-row pale, 1.5# Munich, and .5# crystal 30-L, so 4.8 gallons of strike water total. We added an additional 2 quarts to bring the temp up to 159*. Our sparge (170*) ended up being around 5.5 gallons or so, although I’m not positive.

Pietro - you actually answered a Q I had a few weeks ago about top-cropping a Belgian with dextrose addition. On that same beer, we mashed using the same ratio for 120 minutes at 150*, and came out at 82% efficiency… we actually had to back down the dextrose addition slightly. For this beer, the recipe target FG is 1.015. If we hit that (from 1.062 SG), we’ll be at 6.2 abv (vs. 7.5 abv target), which I don’t have any problem with for this beer, but I do want to know for future beers if I should be doing something differently.

On that note, next time, given the efficiency constraints of a converted Gatorade mash system, maybe I mash at around 155* for 75 minutes or so?

I have never heard of mashing that high. Never personally tried it, but your poor efficiency may be a result of the fact that you’re getting outside of the happy range where the enzymes like to work. In fact, you’re getting dangerously close to the point where they denature alltogether (168ish). If your thermometer happened to be off by a few degrees, that would put you into not good territory real quick.

Be glad you got as good efficiency as you did, and expect a not particularly fermentable wort. But, you’ll still make beer.


Ok, so according to Palmer, the optimum temperature range for beta-amylase is 131-150, and alpha amylase is 154-162. These enzymes are what turn your starches into sugars, you won’t get wort without them. They operate at least some outside their “optimal” range, but you want to be at least in the ballpark. I think its safe to say that you’re high enough to not be getting crap from the beta anymore, and you’re also dangerously close to being sub-optimal for alpha. So, less than great efficiency at that temperature doesn’t surprise me, particularly if your thermometer is perhaps off by a degree or 3.

Good luck, and let us know how it turns out.

What was the OG? Efficiency is not a constant. Efficiency goes down with higher gravity. If on the average my efficiency is 80% for an 1.060 beer but then I try to make a 1.080 beer, I know based on experience that my efficiency will fall to around 60-65% unless I sparge more and boil longer. Perhaps this is the key you were missing?

I really like Petro’s take on this, but I think mash pH is a critical part missing from the discussion here. Maybe your inefficiency was due to mash pH out of range? I target 5.3-4 and have done beers with 160F mashes, beers with 20% crystal malt grain bills, and I get typical FGs. I think mash pH is often overlooked as a factor to fermentability.

dmtaylo2 - target OG (post-boil) was 1.069, 6.5 gallon pre-boil volume, 5 gallon post-. We achieved 1.062 at 6.25 gallons pre-boil, 4.5 gallons post-.

zwiller - Once again, the District of Columbia Water and Sewer Authority has done me wrong. Using the DC 2012 Water Report[/url] and [url=http://www.ezwatercalculator.com/]the EZ Water Calculator
, I estimate my pH to be 5.65, although that could vary significantly given the age and horrifying decrepitude of DC’s water system (the mineral values I used were averages).

Should I invest in pH testing my water, and potentially correct with calcium or bicarbonate?

Yes. This is likely a pH issue, as the intended OG wasn’t as high as I was thinking so it’s not so much a gravity issue. Could be some combination between the way-high mash temperature, and the pH. It could also be that your thermometer is not calibrated properly or you didn’t measure in enough different spots to know the true average temperature – perhaps you actually mashed way up in the mid 160s and didn’t know it!?

In any case, I predict your final gravity will be way high around 1.024 or something in that neighborhood. There is no way in hell you will hit 1.015 or less. No way.

Yep, that’s a bit high. Since your mash temp and pH were both high (double whammy) you might want to throw in a lb or so of sugar to dry it out and get closer to your intended OG.

A meter is great tool but the water spreadsheets are practically just as good. Your water is looks quite nice to me. In the future I’d target lower a lower mash pH 5.4 using gypsum as you pointed to but not bicarb tho since it raises mash pH. If you want to take things further, acidify sparge to 5.7 with phosphoric acid. Although I used EZ water in the past, I’ve taken a liking to Bru’n water since it has a nice sparge acidification calculator.

I do not know the beer you are brewing but all my IPA’s get gypsum to 300ppm sulfate, mostly added to boil.

We’ve calibrated our thermometer using ice water, and checked it against several others, so I’m pretty confident in it’s measure of our mash temp. Perhaps we’ll mix a lb of sugar in with a pint of water or so, and add it tonight or tomorrow to help it get down. Probably pick up some gypsum and litmus strips as well.

I assume you will boil water and sugar a bit and cool before adding.

[quote=“zwiller”]I assume you will boil water and sugar a bit and cool before adding.[/quote]Or just skip the water and add dry.

I agree – adding some sugar is a good idea. I’d boil the sugar in a little water for 5-10 minutes to sanitize.

Ha Ha, this made me throw up a little bit. Being from the DC area and having driven by the Blue Plains treatment plan on many occasions, I gag at the thought of it. But I am sure it is fine. :shock:

When doing Belgians, we’ve always boiled the sugar in water, then cooled it to the fermenter temp before adding, to sanitize and to deaerate the water.

Running the mineral averages from WASA’s report, it looks like we should have some net alkalinity in our water supply. Yet our most efficienct mash to date has been 100% pilsner, which is where water quality should have hammered us the most, relevant to other, darker beers we’ve done. :?