I asked before and got some help and have done some reading since. The temp in my mash jumped from 175 to about 195 after I put the lid back on. How much damage did I do? Some things I've read since suggest that it may be okay since the density of the grain(and, in this case, about 8lbs of cooked pumpkin) may have kept the center mass of the mash somewhat insulated. Opinions? There were some spices(cinnamon, nutmeg, ginger, cayenne) added so it may mask any tannins.

  • where/how did you measure the temp? How long was the mash at this temp? – dana Dec 20 '11 at 20:19
  • I see from your other post you were at 190 for 40 min. – dana Dec 20 '11 at 20:23
  • It started lower, about 170, and fluctuated.. I used a fry thermometer through the lid. When I pitched the yeast I got a good bubble, so I there must some sugar. – Michael Winkeler Dec 20 '11 at 20:43
  • Is there a way to salvage it? – Michael Winkeler Dec 20 '11 at 20:44
  • what's kumara? so I can try it to. – TomMy Darris Dec 16 '16 at 23:24

@dana's answer is full of good info. I'd only make one change: if I were you, I would just wait it out and see what happens. It's possible the beer is ruined, it's possible it's the best beer ever, but it's probably somewhere in between.

Tasting the final beer will be an excellent learning experience, if nothing else. Learning from our mistakes is just as important as making great beer, in my experience.

  • Good Point Joe. What do you think about throwing in some Roselare and putting under the stairs for a year? – dana Dec 20 '11 at 20:48
  • Thanks. I may as well wait it out. Beer is in the primary and there's nothing to gain by pouring it out. May as well let it ride. – Michael Winkeler Dec 20 '11 at 20:50
  • hopefully it's just a bad thermometer:) – Michael Winkeler Dec 20 '11 at 20:53
  • @dana: I've only used Roselare once and the beer is still in a wine barrel, so I'm not qualified to comment :) But I'm a fan of sours and would certainly take a gallon or two out for a test, especially if the beer finishes very high. I've used Utz pretzel canisters for such tests in the past. – JoeFish Dec 20 '11 at 20:54
  • Bugs can eat bigger molecules, and the tartness might offset the massive F.G. Not only is Roselare his best chance of saving the beer, what could be funkier than pumpkin sour!:) – dana Dec 20 '11 at 20:58

If you measured 190 F at any location in your Tun, I would expect the average temp to exceed 170 F. Pumpkin is mostly water and I don't see it as a significant insulator.

Enzymes are little chemical keys that convert the starch in you pumpkins and grain into sugars that the yeast can consume. There are several families of enzymes and each can only tolerate a certain amount of heat before they denature, or fall apart. Once they denature they cannot be recovered.

All enzymes used in brewing denature at about 170 F. If you held your mash above that temperature for any length of time your enzymes denatured without an opportunity to convert the starch into sugar.

Without this important step, your wort will be composed of mainly starch. I would expect a very high final gravity, and a very cloudy beer.

I hate to say it, but you won't be able to drink this beer.

EDIT: I'm changing my recommendation, if you don't need the equipment to keep brewing. You should definitely ferment this out and see what happens. If you do this, please update the question so we can all learn from your experience.

P.S. - I think there might be a salvage technique you could apply if this ever happens again. IF you accidentally kill off the enzymes, you should cool the mash back down to an appropriate temp (say 145 F) and add Beano. Beano has the necesary enzymes for this job. Periodically perform an iodine test to measure your conversion. When the mash has converted "mash out" or raise the the temp above 170 again to denature the Beano. (Don't skip the last step or the beano will never quit, and you'll have a super dry beer)

  • I dunno, I'm sure I've drunk worse ;) But I agree with the rest of the answer. – JoeFish Dec 20 '11 at 20:42
  • Will do. I plan a duplicate batch this week, minus the temperature error, but I don't need the fermenter. – Michael Winkeler Dec 20 '11 at 20:55
  • An important question to ask here is, What was the result of your Iodine conversion test? – Kevin Colby Dec 20 '11 at 21:45
  • didn't do one yet. Will give it a shot tonite or tomorrow – Michael Winkeler Dec 20 '11 at 22:41
  • @Micheal Just to be clear, the only part of my answer I'm editing is the recommendation to dump. The facts above are all true and you will end up with a low alcohol, cloudy, starchy beer. Your acceptance of the other answer made me worry that you have misunderstood this edit. – dana Dec 21 '11 at 12:37

Not the answer you're looking for? Browse other questions tagged or ask your own question.