Let's Pretend - Mash Temp Question

[violinguy]

Let's say a guy (not related to me at all ) brewed a batch today and his thermometer malfunctioned and his mash temp wound up being 130-140 for 70 minutes? When I used my old thermometer right before I fired up the burner for the boil it said 128 or something. I did pour 2 gallons of 170 degree water over the grains so at least I have that.

Thoughts? Will I wind up with yummy beer at, like, 2 1/2 ABV?

 

[TANSTAAFB]

Did you take a hydrometer/ refractometer reading? I bet you had better conversion than you think, it'll just be highly attenuable. What style is it?

 

[Qhrumphf]

You'll probably get some decent beta amylase activity at those temps (in addition to proteolytic stuff which may be a bigger issue). The problem is that beta amylase isn't very good at breaking up large starch chains, only snips off ends into highly fermentable sugars. It's alpha amylase that does the heavy starch chopping, and may be a bit cool for alpha to work well (at least in a reasonable amount of time), which could indeed mean poor conversion. However if your 170 water was enough to bring it up to better a-amylase temps and it had some conversion time, you may alright. Basically a step mash.

 

[violinguy]

Did you take a hydrometer/ refractometer reading? I bet you had better conversion than you think, it'll just be highly attenuable. What style is it?

It's a dunkelweizen that came in at 1.028 prior to fermentation. Was supposed to be 1.048. I will say, that I tasted it before pitching and it tasted great. Beautiful color. At the end of the day, I was at about 44% brewhouse. Ugh.

 

[violinguy]

However if your 170 water was enough to bring it up to better a-amylase temps and it had some conversion time, you may alright. Basically a step mash.

It took me about 20 minutes to pour the water over the grains so hopefully I got some sugars out of there. I'm using Mangrove Jack M20 yeast and trying to ferment colder rather than warmer. Around 68-70 instead of near the higher end of the yeast's range.

I noticed the thermometer issue after it took 45 minutes to get (allegedly) 152 degree water up to boiling. So, what have we learned? Don't buy a cheap oven thermometer at Wal-mart.

**EDIT** I should have said, I realized that the thermometer was probably bad after my pre-boil reading was really low. Then it took 45 min. to boil.

 

[ChelisHubby]

When all is said and done a good trustworthy thermometer is one of your best friends when you are making beer! beer is all about time and temperature!

 

[Qhrumphf]

You can actually introduce enzymes yourself to finish the job (think beano). I've never done it, and my understanding is that artificially adding enzymes can be an easy route to superannuation (as the enzymes basically won't stop).

 

[Draken]

Your friend would have created a beer, that while yummy will be between 2-3% ABV

 

[Shepbrew]

A little while back I had a very vigorous boil going and the kettle thermometer was reading only 180f...well used the same thermometer to get my mash water to what I thought was my desired temp....guess that was off too. Beer was ok, not great.

I now check my thermometers calibration against each other pretty regularly. The one that was originally off seems to slip every few batches whereas the other two I currently have going have never once varied.

 

[violinguy]

Thanks everyone for your responses. I've got some nice activity in the fermenter (yes, I know airlock bubbles are not a sign of good or bad fermenting ), and I'm pretty much right at 68-72. At least I'll get some of the nice flavors from the Bavarian Wheat yeast (want more clove than banana). I'll let you know how it turned out in about 3-4 weeks.

Funny thing is, I posted a while back about how much I love my new thermometer and couldn't imagine how I brewed without it. I brewed better without it.

 

[violinguy]

Bottled this batch today, and as suspected, it's 2.76% ABV. Sigh. On the plus side, it looks awesome. I love the color and there is a fairly pronounced clove taste. Not so much on the banana, which is fine by me.

I absolutely hate that aside from the malfunctioning thermometer I did more correct on this batch than any before it. Edited the recipe a dozen or so times to get the right % of grains - especially for color which I love. Hit every procedure during brewing almost exactly right. Fermented a little low to get more clove and less banana. Did a poor man's cold crash (loaded swamp cooler with ice and got the temp down to about 45-50) for 8 hours before bottling and it is noticeably clearer than any other batch I've brewed.

Lesson learned. Don't skimp on essential equipment like thermometers. When all is said and done, I brewed the best session dunkels weizen ever!

 

[AkTom]

Nicely done.

 

[brandonlovesbeer]

What temp were you going for? Your mash was probably super high converted.

 

[TANSTAAFB]

Love this...poor man's thermopen!

Lavatools PT12 Javelin Digital Instant Read Meat Thermometer (Indigo) https://www.amazon.com/dp/B00GRFHVXQ/?tag=skimlinks_replacement-20

This is the higher end one. Don't own one but with the quality of the $25 one it's gotta be good

Lavatools Javelin PRO Duo Ambidextrous Backlit Instant Read Digital Meat Thermometer (Indigo) https://www.amazon.com/dp/B01F59K0D2/?tag=skimlinks_replacement-20

And they wind up on lightning deals or on sale pretty regularly. Homebrewfinds.com is always on it!

 

[violinguy]

What temp were you going for? Your mash was probably super high converted.

Wanted a mash temp of 148-50 and got a mash temp (measured with my old and very accurate thermometer) of between 120-130. The attenuation of the yeast was 77% so it did its job.

 

[65C]

I think airlock bubbles are a pretty good sign - I also wager this ends up being a good drinking beer after it's properly carbonated

 

[violinguy]

I cracked one open (albeit very early) and lo and behold it tasted amazing! Now I'm even more pizzed off that the mash was messed up. It's a little heavy on the clove, but once it's properly conditioned, I'll bet it's a winner - even at 2.76 ABV

 

[Lefou]

Your friend would have created a beer, that while yummy will be between 2-3% ABV

It's a situation you can learn from and take away a couple lessons. The downside is needing a better thermometer, but the upside is figuring out how to get a drier beer.
One of my next tricks is to attempt a Belgian table beer, low ABV, and dry.

 

[MSK_Chess]

I use digital thermometers but always check them with an old fashioned glass thermometer.
It sits upright in the mash tun just awesome, cost 5 bucks.

 

[Lefou]

In the past, I've experienced brewhouse efficiencies below the expected value. Because of this, a few extra steps were taken to remedy the problem, one of which was to alter the recipe for a higher diastatic power. On my present blonde ale, the pre-boil gravity was a few points off calculated, but still came in within style range.
This particular ale attenuated well below my expected final gravity. I was surprised, but not disappointed because the beer turned out nicely.

Wondering if anyone else could give recommendations on nice accurate thermometers and why they prefer them?

 

[Qhrumphf]

Thermapen, hands down. It's expensive compared to others, but it's extremely fast and extremely accurate. Only downside is a relatively short probe makes reading deep difficult.