overshot my mash temps by alot, reason for lower OG?

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Rivenin

Rivenin

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i searched and couldn't find too much on the subject.

so a few issues came of this

1) i had to use another brew pot i've never used before, VERY thin walled and basically, did not control the temps well and bring it steady up to the temps where it needed to be.

2) i had my thermometer set where it normally goes, but because of the thin walls, it was showing about roughly 20 degrees off (found out that part later)

so i started mashing in thinking my water was at 160, so i took it off the burner, doughed in, let it rest for about 5 mins, took another reading with the thermometer and it was at 170, quickly grabbed my analog thermometer and threw it in and read almost 175, while quickly throwing my other digital in the trash (numbers were jumping from 150 to 170 within about 10 seconds and back down) i put it in the sink, filled the sink with cold water and let it rest for a while stirring around and watching the temps drop, put some cold water in as well, but it must have taken 15 minutes to get it down correctly...

now while i know it's not a horrible thing to do and it will still turn into beer, but the kit i bought said the OG is supposed to be around 1.051 but i measured the final gravity at 1.043... would the way high temps have caused that?

i used 1.25 qts per lb of the mash in.
sparge i used .5 gal per lb.
 
The biggest risk of overheating would be denaturing of the enzymes. I'm no scientist, but I suppose that could account for some lack of efficiency. But there are also lots of other reasons for poor efficiency... mash tun design, ingredients, sparge process, etc,etc.
 
The high mash temp wouldn't make your OG low. It will make you FG really high, since the enzymes weren't able to convert the starches in the malt to fermentable sugars.

What's your setup like? What type of efficiency do you normally achieve?
 
Conesus_Kid said:
The high mash temp wouldn't make your OG low.
Click to expand...

You missed my point. If the temp was high enough to denature the enzymes then there would be no conversion from those enzymes that were denatured. Hence the only thing he would be left with would be whatever enzymes weren't denatured (the ones that were extracted post cooling).
 
BigB said:
You missed my point. If the temp was high enough to denature the enzymes then there would be no conversion from those enzymes that were denatured. Hence the only thing he would be left with would be whatever enzymes weren't denatured (the ones that were extracted post cooling).
Click to expand...

Um, I didn't miss your point. I was agreeing with it. :mug:

If the enzymes are denatured, there won't be fermentables for the yeast. After fermentation, the FG will end up a lot higher than predicted.

I had a stout that I inadvertently mashed >162 F. According to Beersmith, it was supposed to finish at 1.014. Because of the high mash that denatured the enzymes, it finished at 1.024.

I also agree that the OP has a different issue causing the poor efficiency.
 
I realize you were mostly agreeing with me, but what I was saying was that if the enzymes were denatured, he wouldn't get conversion of sugars from the enzymes that were denatured... which would cause the OG to be low. And yes, I agree with you that a high mash temp would cause a less fermentable wort. At 162 you would get a less fermentable wort, but you would still get conversion. The conversion you are getting is of longer chain sugars that the yeast have a hard time fermenting. However, the concern is that at a very high mash temperature (170+) the enzymes are denatured and aren't converting anything.
 
Ah, now I see what you're saying.

I didn't realize that the starches in the malt wouldn't dissolve in the mash water like sugars do, thereby impacting the OG. I thought they would dissolve, but wouldn't be fermented.
 
Enzymes don't denature automatically at 170, that is a bit of a myth. 170 is an important temp. because that is when tannins are extracted. That is why you don't want to go above it. Beta-A will denature, but it will also work quicker in the meantime. Alpha-A will keep going and efficiency will improve at 160F and above.

So, the low Original Gravity, is probably not a result of the few minutes spent at 165-175. It is probably for all the usual reasons: ineffective sparge, bad pH, bad crush, not collecting enough volume, etc.
 
pkeeler said:
Enzymes don't denature automatically at 170, that is a bit of a myth. 170 is an important temp. because that is when tannins are extracted. That is why you don't want to go above it. Beta-A will denature, but it will also work quicker in the meantime. Alpha-A will keep going and efficiency will improve at 160F and above.

So, the low Original Gravity, is probably not a result of the few minutes spent at 165-175. It is probably for all the usual reasons: ineffective sparge, bad pH, bad crush, not collecting enough volume, etc.
Click to expand...

I agree and that is why I said that some of the enzymes are denatured- I said nothing of a catastrophic, mash wide failure of all enzymes. Obviously a measly .008 point difference would not be explained by a denaturing of all the enzymes... the difference would be much greater if it was "automatic" as you say. My point was simply that a high temp of 170 + would destroy some enzymes that could otherwise convert starches. Further I agree with you that the more likely culprit is something else, but the high temp is something that cannot be ignored.
 
Hey guys!
Thanks for the replies :)
I Apologize for not getting back sooner as i really haven't been around a computer.
setup - just like death brewers, one pot on the stove for mashing and another larger for sparging then putting them both together, add extract then brew as normal.

So as far as i can understand from all the posts. The high temp of the mash would have partially caused the drop in OG?

also, will it be a good idea to get ahold of a 5.2 PH balancer?

(i am grabbing more advanced all grain stuff after tax season, eg. cooler... lol)
 
So if you do AG, what is your usual efficiency? Do you usually get what your recipes intend? Because if not, there might be something more consistently wrong (ie. pH, crush, or volume disparities). Do you crush the grain yourself?
 
mym LHBS does all the grain crushing for me.
This is a partial mash recipe (guess i should have said that part, whoops!)
this is also my first "lots o grain" (eg, more the steeping grains) type of brewing as well.
My usual efficiency though is fairly high (never fully tested as it's always been steeping grains)
 
I would say no, the high temp does not affect your OG.

As I referenced Palmer in my last post, the starches in the malt will still dissolve in the hot mash water. Whether the starches are converted into fermentable sugars or not is a function of the enzymes. If you mash too high, you can denature the enzymes so the starches won't be converted to fermentables and will affect your final gravity after fermentation.

I wouldn't bother with the 5.2 pH balancer unless you have tested and know the pH of your mash.

If you haven't before, I would recommend checking out Palmer's book 'How to Brew' and/or website. Lots of good information and he really helps you take the guesswork out of brewing.

FWIW, I used the same setup as you for over a year, and was able to get more efficiency after sparging by letting the bag of rinsed grains drain in a metal colander into the brew kettle. I would then press down on it with the BK lid, squeezing the wort from the grains.

Good luck and keep us posted on your next batch!
 
Did you make the recipe or get it off the internet? Or was it a kit from your LHBS? If so, sounds like you need to adjust your grain for a lower efficiency, since you have never done a PM recipe before. Efficiency really only applies to PM and AG, since in extract the maltster has already gone through the process of mashing for you (ie. efficiency doesn't matter/isn't relevant on your end).
 
Conesus_Kid said:
I would say no, the high temp does not affect your OG.

As I referenced Palmer in my last post, the starches in the malt will still dissolve in the hot mash water. Whether the starches are converted into fermentable sugars or not is a function of the enzymes. If you mash too high, you can denature the enzymes so the starches won't be converted to fermentables and will affect your final gravity after fermentation.

I wouldn't bother with the 5.2 pH balancer unless you have tested and know the pH of your mash.

If you haven't before, I would recommend checking out Palmer's book 'How to Brew' and/or website. Lots of good information and he really helps you take the guesswork out of brewing.
Click to expand...

I disagree. Palmer never says this. Further, it would assume that merely putting grain in hot water will result in 100% extraction of all sugars. If this were true, your OG would always be a measure of 100% of the available sugars in the grain... which we all know is not the case. Your OG is a factor of the efficiency of the extraction of the available sugars, not of the amount of sugars in the grain. What I do agree with is that the culprit is likely something else. Generally the crush has lots to do with efficiency. I also agree not to worry about the 5.2 because the mash itself will bring down the PH unless it is really high.
 
I apologize if I appear to be nitpicking, but you keep refuting this point and you're wrong.

From Palmer:
The starches in the mash are about 90% soluble at 130 °F and reach maximum solubility at 149°F. Both malted and unmalted grains have their starch reserves locked in a protein/carbohydrate matrix which prevents the enzymes from being able to physically contact the starches for conversion. Unmalted grain starch is more locked-up than malted. Crushing or rolling the grain helps to hydrate the starches during the mash. Once hydrated, the starches can be gelatinized (made soluble) by heat alone or by a combination of heat and enzyme action. Either way, an enzymatic mash is needed to convert the soluble starches to fermentable sugars.

http://www.howtobrew.com/section3/chapter14-1.html

Nowhere did I reference or assume 100% efficiency. I am stating that high mash temperature (and the resulting denatured enzymes) does not reduce the original gravity. Specific gravity is simply a measure of the wort's density, whether it's sugars or starches (or salt or anything else) dissolved in the wort. This measurement does not differentiate between fermentable sugars and unfermentables, including starches.

Again, sorry if I sound like a dick here, but the fact of the matter is that the high mash temp. won't affect the OG, just potentially the FG.
 
I guess we will have to agree to disagree. I think you are making lots of assumptions with an erroneous premise.
 
Well complex or simple sugars will effect your FG more then your OG. The OP says that this is still a partial mash. Usually what causes low OG is the inconsistancy with top off water over extracts. Chances are the wort wasn't stirred enough. If you post the recipe, we might be able to judge how much extraction you *should* have gotten with grains.
 
"Did you make the recipe or get it off the internet? Or was it a kit from your LHBS? If so, sounds like you need to adjust your grain for a lower efficiency, since you have never done a PM recipe before. Efficiency really only applies to PM and AG, since in extract the maltster has already gone through the process of mashing for you (ie. efficiency doesn't matter/isn't relevant on your end)."


By LHBS, i meant AHBS (austin home brew)... too early in the AM and i had not enough coffee :)

and it was a kit, one of their "commercial verisions" of home brews.
(saying that because i don't think it would be a good idea to post the recipie of theirs)

but basically it's 3lbs of grains and 5lbs of LME.

did the mash for 60 mins with 1.25 qts of water per lb of grain. (which was above 170 for about 10 mins, but got it down to right about 155* for the other 50 mins)
sat it in a strainer above the pot till it looked like it was done draining

did the sparge with 1.5 gallons of water per lb of grain for 10 mins. (did this at 170, which is what i've been reading)
set the bag in a strainer above the pot and didn't squeeze it, but twisted the bag till it was tight and let it drain again.
combined them both, got boiling, added malt extract, stirred for awhile and put it back to boil and did the 60 mins of boiling as normal

topped up the bucket to 5 gal like normal, pitched the yeast and was done.


"Chances are the wort wasn't stirred enough."

not sure what this means.
 
Rivenin said:
"

"Chances are the wort wasn't stirred enough."

not sure what this means.
Click to expand...


What he is saying that the density of the top off water is different than the density of the wort. If you don't mix the wort and the top off water thoroughly together, you can get a an inaccurate reading due to the stratification of the different density solutions. In other words, you could have a really low reading if you take your hydrometer sample from the top of the mixture because the sugar dense wort is below the layer you are measuring. To get an accurate sample, you must mix the solution really well for a couple minutes after topping off. This not only helps with an accurate hydrometer sample, but it also helps with aerating the wort which is good for yeast growth.
 
i did not even think about that...
that makes quite a bit of sense, and i wish i would have thought about that!
Well i guess i have a good starting point for the next batch hopefully next weekend and keep an eye out for things!

Thank you to everyone for all of the information and i will keep everything in mind
 

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