Re-mashing???

So my freakin' meat thermometer is way off and reads 20 or so degrees too high. So my mash and strike (BIAB) were at way too low temps so I only got 66% efficiency.

So I decided to take the bag of not- spent enough grains and put them back into the wort and mash a second time with a better thermometer. So they are sitting in 155 degree wort for an hour.

Good idea? Bad idea? Utterly horrible idea?

Well, I'm doing it. Grumble. (Freakin' meat thermometers.....)

Well, only got 2% more efficiency after remashing. Mis-did the math on calculating target O.G. 66% would have been fine. Oh well.

If you were thinking you were mashing in the 150 range and you were actually mashing in the 130 range, you will have a lot of beta amylase enzymes which will create a wort with highly fermentable sugars. The temperature had no bearing on your efficiency. The temperature determines how fermentable your wort will be. The little improvement you showed was probably from rinsing the grain with your wort.

You will probably have a very dry beer which is some cases can be very nice but it will also have a lot more alcohol than you planned.

So there is beta amalase at temps that low (130s)? I kinda thought OPs plan was a good idea. Maybe that shows what I know.

For the future: Say someone else asks the same question. At what point is it TOO low for any enzyme action? This would be the point at which you really DID NOT mash at all, you just did a warm soak.

freisste said:

So there is beta amalase at temps that low (130s)? I kinda thought OPs plan was a good idea. Maybe that shows what I know.

For the future: Say someone else asks the same question. At what point is it TOO low for any enzyme action? This would be the point at which you really DID NOT mash at all, you just did a warm soak.

Click to expand...

Basically anything below 130 degrees will not produce a conversion. You may get something below 130 but I don't think it will be much. Here is a good chart explaining mash temps. http://realbeer.com/jjpalmer/ch14.html

150 degrees is probably the most popular temp to mash because it gives a good mix of both beta and alpha amylase enzymes. You mash lower than 150 if you want a highly fermentable wort with less body and higher if you want a less fermentable wort with more body.

Also one other thing for the OP, when you add anything to your mash, be it grain, hot water, cold water you have to make sure you stir it in thoroughly and give it a few minutes to see where the temperature settles. You also want to make sure you have a quality calibrated thermometer.

Very interesting information. Thanks.

I have no idea what temperature I mashed at the first time. The second time I let the grains set in the high 150s and then back up to 170 for ten minutes.

So I guess I need to figure out why my efficiency was 78 percent last week but only 66 percent this week.

Hmmm, when in doubt, blame the mill... (The mill was the LHBS' fault... not mine! )

Diastase enzymes are active at lower temperatures...those are just the optimal temperatures for converting a mash in reasonable time. The problem with lower temperatures is that you don't get complete starch gelatinization.

As Palmer states:
"The starches in the mash are about 90% soluble at 130 °F and reach maximum solublity at 149°F. Unmalted grains have their starch reserves locked in a protein matrix which prevents the enzymes from being able to physically contact the starches for conversion. Only by crushing or rolling the grains is the matrix broken up. The starches can be gelatinized (made soluble) by heat alone or by a combination of heat and enzyme action."

If you're no-sparging then your efficiency can vary depending on grain bill size and mash thickness.

This why I use my floating thermometer in my biab mashes. I get an accurate reading of my mash temp. I also use a dial type thermometer in the kettle heating the sparge water. I've been getting good efficieancies at 152-153F.
As an interesting aside,I use lighter grains & extracts when doing my light hybrid lager,for example. I get light color but fuller flavor,kinda like German or Euro beers of like style.

Did this once to make a second lawnmower beer from a Wee Heavy I brewed. The second beer was about 2.5%, thin, and had an astringentcy that never went away.

Bottom line: it wasn't a great. But I may try the experiment again next time I brew a barleywine because it basically only costs a couple more ounces of hops.

Beernik said:

Did this once to make a second lawnmower beer from a Wee Heavy I brewed. The second beer was about 2.5%, thin, and had an astringentcy that never went away.

Bottom line: it wasn't a great. But I may try the experiment again next time I brew a barleywine because it basically only costs a couple more ounces of hops.

Click to expand...

Ah, but you're talking about using the grains for a second batch altogether. I was talking about redoing for the same original batch.

Ok. I understand now.