I think I F**ked up

[Sykomiko]

So... I missed my OG by about 9 points... I was shooting for 1.091 and I hit 1.082. This is only my 5th batch of AG. So far, I've hit all my numbers (mash temps, and OG's) pretty darn close. This time however I ended up f***ing up my strike temp and mashing in at 160 degF (I was shooting for 156). Am I going to loose efficiency at this high of a temp? Does effieciency suffer as you reach for higher gravities? Or did I just lose 2 points for each pint of porter?

mike

[Bugeater]

So... I missed my OG by about 9 points... I was shooting for 1.091 and I hit 1.082. This is only my 5th batch of AG. So far, I've hit all my numbers (mash temps, and OG's) pretty darn close. This time however I ended up f***ing up my strike temp and mashing in at 160 degF (I was shooting for 156). Am I going to loose efficiency at this high of a temp? Does effieciency suffer as you reach for higher gravities? Or did I just lose 2 points for each pint of porter?

mike

The temp has nothing to do with the efficiency (it will cause some other problems, though). When you go for the higher gravity in an all grain, your efficiency will suffer because you end up not sparging enough to get all the sugars out. To get the same efficiency you had been getting you would have to sparge so much you might need a 3 or 4 hour boil to get your gravity and volume. You would also need a much larger boil pot. I generally just adjust the recipe for about 10% less efficiency when I do a big beer like that ( i.e., if you normally get 70%, set your software to 60%).

The problem you will get from the high temp will be more unfermentable sugars. You may end up with a quite high final gravity. I have learned from experience to mash big beers like this down around 150° and/or use a couple pounds of table sugar as part of the fermentables in order to get the FG to a reasonable level. Your mileage may vary, but this is my experience.

Wayne
Bugeater Brewing Company

[mykafone]

Dont worry - My last big beer I missed by more than that and I freaked out.. but ya know what it still kicks ass.. Next time im going to just add more grain. I know it feels weird calculating a recipe using a WAY lower efficency but do what ya gotta do.

[Sykomiko]

Thanks guys. That makes sense. I did use less sparge water than I usually do. I had to fortify the recipe with extract since my mash tun isn't big enough for all that grain. That brought my volume up in my kettle which is barely big enough for 6 gallons pre-boil as it is...

I guess I'm not terribly concerned with the mash temp. It's a strong scotch ale, so it should have a somewhat high final gravity... It's just a matter of waiting to see what happens...

mike

[Harleybrews]

From my experience, Bugeater is right on. Your 160 mash temp. may yield a less fermentable wort, and leave you with a final gravity higher than you were hoping for. It would be interesting to see how your final gravity compares to what you were shooting for. Maybe you could post your final gravity.

[eric_lord]

if you missed your mash temp, why not add a little cold water and bring it down? 160 seems really high.

My efficiency is terrible with the bigger beers, 60-65%. With my smaller beers I enjoy a 82-91% efficiency. Just something you have to account for.

eric.

[brewsters millionths]

if you miss your mash temp and bring it back down you will not lose anything if you just leave it a little longer. it's only going the other way that doesn't work trying to rebuild the dextrins after you've broken them down won't work.

[BeerMan]

I usually keep a couple pounds of DME lying around in case of such an emergency; if I’m brewing to a style I take gravity after transferring wort to boil pot and do temp and evaporation correction then I add DME or filtered water if required to adjust gravity to style prior to the boil. This method works well I can hit my predicted OG + or – a point. If you add a pound of DME to a 16lbs grain bill flavor is not affected and know one will be the wiser.