I'm brewing a robust porter. My first mash got away from me and when i noticed the mash was at 170 degrees and could have been there for more than 10 minutes (brewing on NFL sunday problems). I finished the entire process, none the less, and have it fermenting in a 1 gallon carboy. I had remaining ingredients and made the same exact beer again, this time paying attention to temp keeping it in the 145-150 range. Today i took samples (7 days later) and saw the ABV of the over cooked porter to be 4.2% and the one i did more accurately was at 8.6%. The goal abv is 9%, i was wondering if anyone has had something like this happen, and any opinions on adding more sugar to the lower ABV beer. I know 4.2% is a fine drinking beer, but just coming from the scientific experiment side if its possible to raise it.
If you require more ABV than add suger or some other fermentable product in the primary, sometimes the secondary but otherwise, monitor your mash temps in the future and enjoy your 4.2. Adding sugar may raise the ABV , but will definatly change the beer.
170 degrees for even a couple of minutes would lead to a beer with a lot of unfermentables and therefore a low ABV. As @GormBrewhouse said, you could add sugar or DME to raise the ABV, but in my opinion, it is rarely (never?) worth it. Just go with what the yeast gave you and move on. P.S. brewing and drinking at the same time leads to lots of posts like this You might want to brew during the pregame and then enjoy a beer and the game when the brewing is done.
I would consider blending the two batches, but I wouldn't just add sugar to get more alcohol, You could, of course, if you choose, but I would recommend either blending or standing pat with each and comparing them after bottling. You could also blend in the glass, too.
170F (or thereabouts) is called the mash out temperature. It's used to intentionally denature enzymes after the saccharification rest is done. It sounds like your mash got to 170F well before it was done making sugars. It's possible. But I wouldn't do it. Adding sugar could get you to the ABV level you want, but it isn't going to be the same beer as the other (properly mashed) batch at all. There's really nothing experimental about it. If you decide to do it, each pound of table sugar added to a 5 gallon batch will increase your ABV by about 1.47%.
Hide the fermenter in the corner of a closet, drink many sour beers, dump the dregs of these sour beers into fermenter. Keep airlock filled, check back in 12 months. If you don't want to try this experiment, i would dump the batch and call it a learning experience. Make another batch asap to kill the pain of your lost batch. Cheers
I hate dumping beer, so here's a second vote for blending. I would fill one bottle 50-50 and carbonate two weeks. If it worked, then blend both beers and bottle the rest.
