Mash Temp

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Lets start again..beer/mashing/enzymes
Alpha and Beta Amylase enymes are encouraged by the malting (essentially germination) process.
Ath e end of the malting process there is a lot of grain and not much liquid, in fact screw all.
Kilning temps for pale malts (and I include Vienna, and Munich here) will not denature the enzymes.
When we mash, the higher the liquid to grain ratio is the more heat lablile are the enzymes, in particular Beta Amylase.
Roughly spaeking for a L:G of 2:1 to about 4:1 at 66C you will knock your beta out in about 20-30 minutes.
Denaturing or the heat death of the enzymes is time, temperature and thickness dependant.
To posit that mash tempertaure determines enzymatic activity (alone) shows at least some knowledge but not an understanding.
There is much to be found by simple googling on this subject.

K
 
According to this, Wiki article on Mash ingredients, Malt is kilned at temps ranging from 55-200C (depending on type of malt).

Notably, Pale Malt is kilned at 95-105C (well above our mash temps). So from this, I'd say that the enzymes won't denature during kilning because the malt is dry while this is happening. Things change once the malt is wet and the enzymes can interact and do their thing.

PBR, if you could post tasting notes on how your beer turns out, it would be good to see if the enzymes were able to convert with such a high mash temp and what the result is.

HC

Edit: What everyone said above me
 
.

Notably, Pale Malt is kilned at 95-105C (well above our mash temps). So from this, I'd say that the enzymes won't denature during kilning because the malt is dry while this is happening. Things change once the malt is wet and the enzymes can interact and do their thing.

Pretty much what dr K and the article I linked previously have suggested.
 
Lets start again..beer/mashing/enzymes
Alpha and Beta Amylase enymes are encouraged by the malting (essentially germination) process.
Ath e end of the malting process there is a lot of grain and not much liquid, in fact screw all.
Kilning temps for pale malts (and I include Vienna, and Munich here) will not denature the enzymes.
When we mash, the higher the liquid to grain ratio is the more heat lablile are the enzymes, in particular Beta Amylase.
Roughly spaeking for a L:G of 2:1 to about 4:1 at 66C you will knock your beta out in about 20-30 minutes.
Denaturing or the heat death of the enzymes is time, temperature and thickness dependant.
To posit that mash tempertaure determines enzymatic activity (alone) shows at least some knowledge but not an understanding.
There is much to be found by simple googling on this subject.

K



Dr,

What are your thoughts on hydromemter measurements of a wort that may have been mashed under circumstances that denature enzymes rapidly?

My thoughts relate to false +ve hydrometer readings, given they are measuring density, and non-fermentables still modify density.

I see some connections with my weak theory and the few biabers that do not recirc, squeeze the bag out and end up with higher gravities than expected.
Apologies OP, slightly off topic but related in the scheme of things. (Given your hydro may tell you it's ok???)
 
Dr,

What are your thoughts on hydromemter measurements of a wort that may have been mashed under circumstances that denature enzymes rapidly?

My thoughts relate to false +ve hydrometer readings, given they are measuring density, and non-fermentables still modify density.

I see some connections with my weak theory and the few biabers that do not recirc, squeeze the bag out and end up with higher gravities than expected.
Apologies OP, slightly off topic but related in the scheme of things. (Given your hydro may tell you it's ok???)

Bumpy bump - i would be interested to hear a more educated opinion on this as well. When i was using Biab this was always my thinking with the turbidity of the wort pre boil giving a higher gravity reading. This would later translate into more trub at the end of the boil, which would translate into lower OG than expected from the pre boil gravity. Leading to larger discrepancy between mash efficiency and efficiency into fermenter.

I dont experience any of this running clear wort into the kettle, gravities are spot on and very minimal losses / difference in efficiency.
 
Bumpy bump - i would be interested to hear a more educated opinion on this as well. When i was using Biab this was always my thinking with the turbidity of the wort pre boil giving a higher gravity reading. This would later translate into more trub at the end of the boil, which would translate into lower OG than expected from the pre boil gravity. Leading to larger discrepancy between mash efficiency and efficiency into fermenter.

I dont experience any of this running clear wort into the kettle, gravities are spot on and very minimal losses / difference in efficiency.


Not wort, but close. I know by talking with the chief chemist from when I used to work in the sugar industry they would never measure the CCS (Commercial Cane Sugar content) of a sample without first clarifying it.

Even by definition Refractometer brix The term used when a refractometer equipped with a scale,based on the relationship between refractive indices at 20C and the percentage by mass of total soluble solids of a pure aqueous sucrose solution, is used instead of a hydrometer to test the solids concentration of a sucrose containing solution. they talk about a pure solution.

QldKev
 
Not wort, but close. I know by talking with the chief chemist from when I used to work in the sugar industry they would never measure the CCS (Commercial Cane Sugar content) of a sample without first clarifying it.

Even by definition Refractometer brix The term used when a refractometer equipped with a scale,based on the relationship between refractive indices at 20C and the percentage by mass of total soluble solids of a pure aqueous sucrose solution, is used instead of a hydrometer to test the solids concentration of a sucrose containing solution. they talk about a pure solution.

QldKev

Thankyou,

This supports my weak but educated thoughts on the topic.

Perhaps a more effective method for analysing wort pre-boil for SG may be to take a sample, chill to 20C, decant leaving break material
behind and measure Gravity.
I recirc, so my wort is usually quite clear, but i do measure in the cylinder with the break material still in their.

Does anyone have a test that can qualify that enzyme activity has been complete during mash? (Unlikely?)
 
Thankyou,

This supports my weak but educated thoughts on the topic.

Perhaps a more effective method for analysing wort pre-boil for SG may be to take a sample, chill to 20C, decant leaving break material
behind and measure Gravity.
I recirc, so my wort is usually quite clear, but i do measure in the cylinder with the break material still in their.

Does anyone have a test that can qualify that enzyme activity has been complete during mash? (Unlikely?)

iodine test :lol:
 
Not wort, but close. I know by talking with the chief chemist from when I used to work in the sugar industry they would never measure the CCS (Commercial Cane Sugar content) of a sample without first clarifying it.

Even by definition Refractometer brix The term used when a refractometer equipped with a scale,based on the relationship between refractive indices at 20C and the percentage by mass of total soluble solids of a pure aqueous sucrose solution, is used instead of a hydrometer to test the solids concentration of a sucrose containing solution. they talk about a pure solution.

QldKev

always wondered about this...diy centrifuge here i come
 
A hydrometer is a floating device that measure the density of the solution rleative to water (yes)
The trub and the hops are not in solution (?)
Neither is the hydrometer. ( I hope)
The error from reading (meniscus, temperature, calibration,parallax..glass or plastic and thickness) is of a far higher order than a bit of trub, and if you are worried, settle and decant.
Your starting gravity is merely how dense your wort is, not how fermentable it is. I could for example make a solution of lactose and water to 1040, it would read 1040 on my hydrometer, and probably close to that on a refractometer, what do you think would happen during "fermentation"?
The enzymatic activity during the mash determines the types and amounts of sugars that are created, yeast can only work with what it has.
It's all pretty simple if you think about it.

K
 
A hydrometer is a floating device that measure the density of the solution rleative to water (yes)
The trub and the hops are not in solution (?)
Neither is the hydrometer. ( I hope)
The error from reading (meniscus, temperature, calibration,parallax..glass or plastic and thickness) is of a far higher order than a bit of trub, and if you are worried, settle and decant.
Your starting gravity is merely how dense your wort is, not how fermentable it is. I could for example make a solution of lactose and water to 1040, it would read 1040 on my hydrometer, and probably close to that on a refractometer, what do you think would happen during "fermentation"?
The enzymatic activity during the mash determines the types and amounts of sugars that are created, yeast can only work with what it has.
It's all pretty simple if you think about it.

K

Although my jargon is a little off, that is exactly as i understand it.

If for example someone (OP) mashed in high 70's for an hour and denatured the bulk of the enzymes available fairly early in the process, they may find that their gavity reading is as planned for, but the ratio of non-fermentable to fermentable material which they have not established will be out of whack..

In the BIABers case if they produce a turbid beer via dunk and squeeze, the 'stuff' in suspension could influence their hydro-reading, hence a false positive for fermentable sugars.

I guess my question relates to how significant the BIAB situation is in the scheme of the other variables you mention Dr K?

I dont BIAB, but the principle of turbid wort is where my curiosity lies.
 
I think you can pretty much ignore the contribution of hops to the SG, 1 IBU is (roughly) 1 mg of Iso-Alpha/Litre of beer so 100 IBU would be 100/1000 or 0.1g/L, contributing 0.01oP to the gravity or 0.00004 to the gravity, if the other hop products that went into solution were 100 time as massive as the bitterness you might just notice them on an hydrometer (maybe).

If you look at a grain COA you will often see saccrification time in the 10-20 minute range this is the time it takes the enzymes to make the starch soluble, its far from the time required to reduce the starches to the right ratio of fermentable sugars and dextrins that we want for beer to taste good.
Were I fermenting this beer, I would be very tempted to take a small sample and ferment it warm (25oC+) and see where it is going to finish, if the terminal gravity is ridiculously high I would seriously consider adding some dry enzyme which will tackle soluble dextrins and reduce them to fermentable sugars.

Anyone who squeezes a BIAB bag gets what they deserve, a bunch of extra protein into the kettle, to no net gain. There are lots of high molecular weight proteins (n=40K+) that condense (form break) at mashing temperatures. In a conventional system these are trapped in the grain bed, the higher the weight of a protein the more harm it can do to the finished beer, squeeze the bag and you can get them out, allow the bag to drain naturally and few if any are going to find their way into the kettle giving you a lot less trub to manage.
 
After reading that thread, I should have paid more attention in my organic chemistry classes. It was interesting to see a bit of the research into it. I will give you my sampling notes to give some input. I personally think that a limited amount of conversion went on. Though not doing the iodine test I have no idea what the conversion was. As I am no longer doing kit And kilo brews all you help is greatly apprecated.
 
Just had to check on the beer because I am going back to work. It is reading 1028. Still has a milky appearance of the yeast still doing its thing. I will post another update when I am back from work.
 
Just had to check on the beer because I am going back to work. It is reading 1028. Still has a milky appearance of the yeast still doing its thing. I will post another update when I am back from work.

Final gravity was 1021. It was a bit on the sweet side.
 
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