Malted
Humdinger
- Joined
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I am primarily interested in Stepped Mashing because I have a Braumeister and can easily do 5 temperature steps/rests on top of a set mash-in temperature.
Some of this discussion could be applicable to RIMS or HERMS or homemade variants of temperature controlled wort production. Even BIAB with a direct heat source under, or in the mash could be in the same category. At a pinch it could be relevant to infusion mashing but that is a different process in which the liquor to grist ratio is changed, that's not where I want this discussion to go. There are a lot of threads about temperature mashing and what mash schedules are suitable for a particular brew. I have tried to draw together some of those threads and stuff I found on the net. Yes I have had a look at Braukaiser.
This is not a topic about decoction mashing or infusion mashing because they are a different process. If you use those processes some of the info here may help you decide on a temperature schedule but I am not interested in this thread, as to how you achieve those temps.
Infusion mashing - generally mash is heated by adding hot water in stages. It is only about changing the temperature of the mash.
Decoction mashing - a portion of the cereal/grain mash is removed and heated before being returned to the mash. This can modify flavours and colours as well as a change in temperature of the mash.
Braumeister, RIMS, HERMS, Braumeiser's et al - the wort is constanly recirculated through the mash and an electronically controlled heat source raises the temperature of the wort.
I am posting what I have found for the purposes of discussion. It is a summary and I invite comment. I am not going to try to discuss all enzymes and the processes of interest or the whole science of mashing (and I only know a fraction of it). I am going to try and keep this simple (so am not mentioning attenuation or efficiency); it may require you to do some reading or research of your own. If you know something I have said to be wrong, please post so that we may all learn. It is a topic that continues to be confusing. I have simplified it a bit, perhaps too much, because I want to know more about mash schedule temps and times, with just enough to get by on the theory of why. The bulk of what I have found is in the first table.
The science of mashing is quite complex and my basic reading has led me to many contradictory statements, facts and figures. Different authors quote different temperatures as being optimal for particular enzymes active in the mash. These authors even use different names for the same processes, for example:
Amylase Rest vs Maltose Rest vs Beta Amylase rest (3 names for the same temperature rest)
Amylase Rest vs Saccharification vs Starch Conversion vs Glyco-protein Rest vs Alpha Amylase Rest. (5 names for the same temperature rest).
In some instances, there are different processes that the authors are concerned about that occur at the same temperature and thus differing names are used. Sometimes it just seems as though there is no standard naming convention.
It would seem that the biggest influences on the enzymes at work in the mash are pH, temperature and duration of the temperature.
Other factors include
water chemistry
the type of malt
milling of the grains
water to grist ratio
diastatic power or enzymatic power the hotter a grain is kilned the less it has
dark malts increase mash pH
many other factors too.
A reasonable read on the above factors can be found at: http://braukaiser.com/wiki/index.php?title=Effects_of_mash_parameters_on_fermentability_and_efficiency_in_single_infu
sion_mashing
I want to specifically look at Temperature and Time (with only hinting at pH) as these are the factors I want to use in Step Mashing in the Braumeister. I have tabulated some of the information that I have collected.
The table should be read horizontally.
The values in the light blue section on the right side of the table are minutes. It shows how many minutes, for a particular beer style, that the mash could be kept at a particular temperature (listed in the vertical column of Optimal Temperature). You can also see that I have stalked Zwickle a bit...
In regards to temperatures and times, the biggest thing is what do you want to achieve with each step of the mash? Hopefully most of this information is in the first table above.
Acid rest
"The acid rest is not used nowadays because it can take several hours for this enzyme to lower the mash pH to the desired 5.0 - 5.5 range" John Palmer, How to Brew.
pH is quite a complex subject in how it interacts in the brewing process (it is also an area I am unfamiliar with). An example of the pH interaction: "Lowering the mash pH from 5.8 to 5.4 increased wort fermentability due to increased limit dextrinase activity. Wort fermentability was more strongly correlated to the free limit dextrinase activity of malt than to the alpha- and beta-amylase activities." http://www.scientificsocieties.org/JIB/papers/1999/1999_105_4_205.pdf
Why then does only one of the mash schedules in the first table above have a limit dextrinase rest? Should I be more concerned about mash and wort pH than I am? Is it ok to look at temperature and times in isolation to pH?
I like the 'idea' of starting with an acid rest because it is quicker for your mash liquor to reach these temperatures for mash in. If you are doing a wheat beer or a beer with >25% rye, oats or undermodified malts, it may be advantageous for you. With these beers and others, if it is done for too long it may have undesirable consequences.
Protein Rest
Seems like a lot of folks refer to "Simple single infusion mash for use with most modern well modified grains (about 95% of the time)" and such quotes about modern well modified grains. These folks say you don't need a protein rest and won't even entertain the idea. It seems like most of these quoting folks haven't tried a protein rest. Some of those that have actually used protein rests swear by them. As some say, a short protein rest is not necessary but may be useful none the less.
Gimme Sugarz!
You can create a wort higher in fermentable sugars, one that is higher in unfermenatble sugars, or try to produce one that balances the two (66oC seems to hit that mark). Both fermentable and non-fermentable sugars are going to be formed at the optimal temperature for the other, it is just one will be favoured. But it is not just about converting starch to sugars; which sugars do you want? Are the temperature steps to favour enzymes that will convert sugars to particular sugars you are interested in for a particulalr reason?
Mash out
Raising of temperatures at the end of the mash to stop enzymes working and makes the grain bed and wort more fluid and can prevent a stuck sparge (but if a Braumeister/recirculating system is not stuck before then, it probably won't stick). Any starches rinsed out during the following sparge will not be converted to useful sugars as the enzymes have stopped working, these starches may cause haze in the finished beer. It doesn't seem likely that a good mash would contain residual starches. A mash out would seem to be important for a mash that contain wheat, oats, rye and undermodified malts.
Temperature and time
Given that the enzymes of interest work over a temperature range (debateable 'optimal' temps listed in my first table) some folks don't change their actual temps, just the duration at those temps. Essentially each step or temp rest will do something desirable, you just want to change the particular ratios of resulting products from enzymatic activity in the mash by varying the times at those temps. For instance, I made the table below by stalking Manticle (cheers mate!
) as he is one of the few to regularly list his mash schedules. Note that he pretty much uses the same temperatures but just varies times of each step for differing brews:
*actually 1oC lower
**was 69oC
***was 75oC
You can see that the Saison would favour the production of a greater amount of fermentable sugars than the EIPA.
The Beersmith program says:
Light body = 64.4oC for 75 mins
Medium Body = 66.7oC for 60 mins
Full body = 68.9oC for 40 mins
The literature also supports that the higher temperature enzymes work quicker, so a short rest at higher temps could have more of an affect than you might think. I am thinking about the influence of differing times at differing temperatures.
I am not wanting to start an anti-step mashing debate. With a Braumeister it is no big deal to step mash, if it is not going to have a negative affect and might be beneficial, then I am going to do it, just for the heck of it, because I can.
If you use single infusion mashing with a mashout, or decoction mashing, these questions are not for you :icon_offtopic:
:excl: If you use temperature steps:
what temperature steps do you use?
for how long?
why?
for what style of beer?
Some of this discussion could be applicable to RIMS or HERMS or homemade variants of temperature controlled wort production. Even BIAB with a direct heat source under, or in the mash could be in the same category. At a pinch it could be relevant to infusion mashing but that is a different process in which the liquor to grist ratio is changed, that's not where I want this discussion to go. There are a lot of threads about temperature mashing and what mash schedules are suitable for a particular brew. I have tried to draw together some of those threads and stuff I found on the net. Yes I have had a look at Braukaiser.
This is not a topic about decoction mashing or infusion mashing because they are a different process. If you use those processes some of the info here may help you decide on a temperature schedule but I am not interested in this thread, as to how you achieve those temps.
Infusion mashing - generally mash is heated by adding hot water in stages. It is only about changing the temperature of the mash.
Decoction mashing - a portion of the cereal/grain mash is removed and heated before being returned to the mash. This can modify flavours and colours as well as a change in temperature of the mash.
Braumeister, RIMS, HERMS, Braumeiser's et al - the wort is constanly recirculated through the mash and an electronically controlled heat source raises the temperature of the wort.
I am posting what I have found for the purposes of discussion. It is a summary and I invite comment. I am not going to try to discuss all enzymes and the processes of interest or the whole science of mashing (and I only know a fraction of it). I am going to try and keep this simple (so am not mentioning attenuation or efficiency); it may require you to do some reading or research of your own. If you know something I have said to be wrong, please post so that we may all learn. It is a topic that continues to be confusing. I have simplified it a bit, perhaps too much, because I want to know more about mash schedule temps and times, with just enough to get by on the theory of why. The bulk of what I have found is in the first table.
The science of mashing is quite complex and my basic reading has led me to many contradictory statements, facts and figures. Different authors quote different temperatures as being optimal for particular enzymes active in the mash. These authors even use different names for the same processes, for example:
Amylase Rest vs Maltose Rest vs Beta Amylase rest (3 names for the same temperature rest)
Amylase Rest vs Saccharification vs Starch Conversion vs Glyco-protein Rest vs Alpha Amylase Rest. (5 names for the same temperature rest).
In some instances, there are different processes that the authors are concerned about that occur at the same temperature and thus differing names are used. Sometimes it just seems as though there is no standard naming convention.
It would seem that the biggest influences on the enzymes at work in the mash are pH, temperature and duration of the temperature.
Other factors include
water chemistry
the type of malt
milling of the grains
water to grist ratio
diastatic power or enzymatic power the hotter a grain is kilned the less it has
dark malts increase mash pH
many other factors too.
A reasonable read on the above factors can be found at: http://braukaiser.com/wiki/index.php?title=Effects_of_mash_parameters_on_fermentability_and_efficiency_in_single_infu
sion_mashing
I want to specifically look at Temperature and Time (with only hinting at pH) as these are the factors I want to use in Step Mashing in the Braumeister. I have tabulated some of the information that I have collected.

The table should be read horizontally.
The values in the light blue section on the right side of the table are minutes. It shows how many minutes, for a particular beer style, that the mash could be kept at a particular temperature (listed in the vertical column of Optimal Temperature). You can also see that I have stalked Zwickle a bit...
In regards to temperatures and times, the biggest thing is what do you want to achieve with each step of the mash? Hopefully most of this information is in the first table above.
Acid rest
"The acid rest is not used nowadays because it can take several hours for this enzyme to lower the mash pH to the desired 5.0 - 5.5 range" John Palmer, How to Brew.
pH is quite a complex subject in how it interacts in the brewing process (it is also an area I am unfamiliar with). An example of the pH interaction: "Lowering the mash pH from 5.8 to 5.4 increased wort fermentability due to increased limit dextrinase activity. Wort fermentability was more strongly correlated to the free limit dextrinase activity of malt than to the alpha- and beta-amylase activities." http://www.scientificsocieties.org/JIB/papers/1999/1999_105_4_205.pdf
Why then does only one of the mash schedules in the first table above have a limit dextrinase rest? Should I be more concerned about mash and wort pH than I am? Is it ok to look at temperature and times in isolation to pH?
I like the 'idea' of starting with an acid rest because it is quicker for your mash liquor to reach these temperatures for mash in. If you are doing a wheat beer or a beer with >25% rye, oats or undermodified malts, it may be advantageous for you. With these beers and others, if it is done for too long it may have undesirable consequences.
Protein Rest
Seems like a lot of folks refer to "Simple single infusion mash for use with most modern well modified grains (about 95% of the time)" and such quotes about modern well modified grains. These folks say you don't need a protein rest and won't even entertain the idea. It seems like most of these quoting folks haven't tried a protein rest. Some of those that have actually used protein rests swear by them. As some say, a short protein rest is not necessary but may be useful none the less.
Gimme Sugarz!
You can create a wort higher in fermentable sugars, one that is higher in unfermenatble sugars, or try to produce one that balances the two (66oC seems to hit that mark). Both fermentable and non-fermentable sugars are going to be formed at the optimal temperature for the other, it is just one will be favoured. But it is not just about converting starch to sugars; which sugars do you want? Are the temperature steps to favour enzymes that will convert sugars to particular sugars you are interested in for a particulalr reason?
Mash out
Raising of temperatures at the end of the mash to stop enzymes working and makes the grain bed and wort more fluid and can prevent a stuck sparge (but if a Braumeister/recirculating system is not stuck before then, it probably won't stick). Any starches rinsed out during the following sparge will not be converted to useful sugars as the enzymes have stopped working, these starches may cause haze in the finished beer. It doesn't seem likely that a good mash would contain residual starches. A mash out would seem to be important for a mash that contain wheat, oats, rye and undermodified malts.
Temperature and time
Given that the enzymes of interest work over a temperature range (debateable 'optimal' temps listed in my first table) some folks don't change their actual temps, just the duration at those temps. Essentially each step or temp rest will do something desirable, you just want to change the particular ratios of resulting products from enzymatic activity in the mash by varying the times at those temps. For instance, I made the table below by stalking Manticle (cheers mate!

*actually 1oC lower
**was 69oC
***was 75oC
You can see that the Saison would favour the production of a greater amount of fermentable sugars than the EIPA.
The Beersmith program says:
Light body = 64.4oC for 75 mins
Medium Body = 66.7oC for 60 mins
Full body = 68.9oC for 40 mins
The literature also supports that the higher temperature enzymes work quicker, so a short rest at higher temps could have more of an affect than you might think. I am thinking about the influence of differing times at differing temperatures.
I am not wanting to start an anti-step mashing debate. With a Braumeister it is no big deal to step mash, if it is not going to have a negative affect and might be beneficial, then I am going to do it, just for the heck of it, because I can.
If you use single infusion mashing with a mashout, or decoction mashing, these questions are not for you :icon_offtopic:
:excl: If you use temperature steps:
what temperature steps do you use?
for how long?
why?
for what style of beer?