How to tell if a grain has convertible starches?

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CascadesBrewer

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I am doing some research into partial mashing vs steeping...

My overall question is: Are there guidelines or data from a malt spec sheet that can be used to determine if a light colored specialty grain is a good candidate for steeping or if it should be mashed?

I get that there are some malted grains that have both enzymes and starches (Pilsner, "2-Row", Pale Ale Malt, Vienna, Munich, etc.). There are other grains that do not have enzymes or starches but add flavors and colors (Crystal, Chocolate, Black Patent, etc.). There are others that do not have enzymes but have starches (unmalted/raw grains, flaked barley/oats/wheat/rye, corn, rice, etc.)

I am a little confused about some of the lighter colored specialty grains/malts like Biscuit, Victory, Aromatic, Melanoidin, Dark Munich, etc. Is there information on a spec sheet that would tell me if these grains still have convertible starches? If they have starches, it would make them better candidates for a mash or partial mash instead of steeping. Is the color of the malt a good indicator?

A search turned up the following thread. It had some lists of grains that should be mashed vs steeped, but not info on how to determine which is which. Also, I question some of the info. I would expect a 70L Brown Malt to be fine for steeping. Can only certain grains be steeped?

I also see a table in the online version of "How to Brew": Table of Typical Malt Yields - How to Brew I don't see this exact table in the 4th Edition, but I see one table about steeping and another about mashing. There are a couple grains starred with the note "The low extraction from steeping is attributed to unconverted, insoluble starches as revealed by an iodine test." There are also a number of grains where the extract from mashing is several points higher than the points from steeping. Why would a grain like Chocolate Malt yield 28 points when mashed and only 15 when steeped?
 
A lot of people steep grains that *shouldn't* be steeped. The penalty is potentially hazy beer, with a shorter shelf life.

But basically, steepable grains include Caramel/Crystal Malts and Dark Roasted Malts. And that's pretty much it.

You mentioned Biscuit, Victory, Aromatic, Melanoidin, and Dark Munich. None of those should really be steeped, because they contain significant amounts of unconverted starches. Therefore they should be mashed, along with a base malt that will provide enzymes. In the case of the Dark Munich, depending on which maltster's "dark" Munich you're referring to, it might have enough enzymes for conversion. In that case, it could be mashed without (another) base malt, but not simply steeped, per se.

Brown Malt? I wouldn't steep it. Keep in mind that brewers in England historically used a similarly colored Brown Malt as a base malt. Modern Brown Malts have lost their diastatic power, but I think they probably have a fair amount of unconverted starches. But I haven't actually researched that.
 
From a very uneducated viewpoint, I consider steeping just for adding flavors. Mashing is converting the starches and sugars to something more fermentable.

On the ever so slightly more educated viewpoint, how we mash and the temps we use will yield significantly different sugars that yield different qualities to the final beer.

I've had similar questions and just google to see who is doing what toward making beer with those grains, spices or whatever. And if I don't find much then I'm assuming there isn't much too them. Almost literally from beers day one thousands of years ago, brewers have investigated everything they can find.
 
A lot of people steep grains that *shouldn't* be steeped. The penalty is potentially hazy beer, with a shorter shelf life.

This was some of my initial motivation for digging into this more. I am looking at the extract version of the Brave Noise Pale Ale recipe. It has a step labeled "Partial Mash" but the only grains in the recipe are Flaked Oats and Caramel 20. The recipe also calls for Light DME and Wheat DME. I am thinking of doing one batch with a steep of Flaked Wheat + Flaked Oats + C20, and a second batch with a partial mash of Malted Wheat + Flaked Oats + C20.

But basically, steepable grains include Caramel/Crystal Malts and Dark Roasted Malts. And that's pretty much it.

I understand the basics of how Caramel/Crystal Malts are made and why they would be good candidates for steeping (though I have read that some lighter Crystal malts benefit from being mashed). As far as "Dark Roasted Malts", I wonder if it is the roasted vs kilned aspect that is important or if it is the dark vs medium color aspect. I am not sure how dark a kilned malt can get.

I only know the basics of malting, kilning and roasting, but this PDF seems interesting: https://www.homebrewersassociation.... - Do You Really Know Your Specialty Malt.pdf
 
As far as "Dark Roasted Malts", I wonder if it is the roasted vs kilned aspect that is important or if it is the dark vs medium color aspect.

I would say it's the "degree of roasting," which more or less equates to the color. In these malts, most of the starches have been converted and/or incinerated.
 
A table I found a long time ago. No guarantee of accuracy.
Mash theseMashNot these
Any Base MaltAny Crystal Malt, Most Malts that Start with CARA, Most Caramel Malts, Most Malts that Start with CARA, Special B Malts, Roasted Malts, Chocolate Malts, Roasted Barley, Dark Wheats and Carafa Malts
UK Pilsner 2 RowYesCaraFoam
PilsenYesCarapils
Flaked OatsYesBeechwood Smoked Malt
Malted OatsYesCrystal 10
Flaked CornYesCrystal 20
2 Row MaltYesCaraRed
Flaked BarleyYesMelanoidin Malt
6 Row MaltYesCaraVienna Malt
Golden PromiseYesBiscuit Malt
Bohemian PilsnerYesCrystal 40
Irish Stout MaltYesCaraMunich I
German WheatYesSpecial Roast
White WheatYesCaraMunich I
Wheat MaltYesCrystal 60
Crystal 80
Flaked RyeYesCrystal 120
Rye MaltYesExtra Special
Acidulated MaltYesCaraAroma
Red WheatYesSpecial B
Oak Smoked WheatYesChocolate Rye
Maris OtterYesRoasted Barley
Kolsch MaltYesCarafa 1
Pale AleYesPale Chocolate
Vienna MaltYesChocolate Malt
Cherrywood Beechwood Smoked MaltYesChocolate Wheat
Light Munich MaltYesCarafa II
Golden Naked OatsYesDark Chocolate Malt
Munich MaltYesBlack Patent
Munich 10 (Dark Munich)YesBlack Malt
Red XYes
Abbey MaltYes
CaraHellYes
CaraBelgeYes
Amber MaltYes
Honey MaltYes
Aromatic MaltYes
Victory MaltYes
Brown MaltYes
 
I came across this BeerSmith article: Steeping Grains for Extract Beer Brewing It is a bit old and I am not sure I would treat Brad Smith as the final answer on this, but I suspect he knows more about ingredients that I do.

The article has the quote: Not all grains are appropriate for steeping however. Pale malt, for example, adds very little flavor and should be mashed. Flaked and torrified ingredients such as flaked barley, wheats, munich malt and oats also need to be mashed. To get a complete list of grains that may be mashed, visit our grain listing. Grains marked as “Must mash” should, in general, be mashed and not steeped.

I am not sure how old the "grain listing" is or if it matches up with what is currently in BeerSmith: Gains and Extracts List for Beer Brewing | BeerSmith™ Home Brewing Software

The following are the only lighter colored grains listed that do not need to be mashed (can be steeped) that are not specifically named "Crystal". Biscuit Malt is the only one that is not a type of "Cara" malt. I come across conflicting info on steeping CaraPils/CaraFoam type malts.
  • Biscuit Malt (23 SRM)
  • Cara-Pils/Dextrine (2 SRM)
  • Caraamber (30 SRM)
  • Carafoam (2 SRM)
  • Caramunich Malt (56 SRM)
  • Carared (20 SRM)
  • Caravienne Malt (22 SRM)
It does seem like the rule "steepable grains include Caramel/Crystal Malts and Dark Roasted Malts" is pretty close.

So I guess a side question is: What is the impact (both positive and negative) of steeping a grain that should be mashed? Can an extract brewer add some character from steeping a grain like Aromatic, Golden Naked Oats, Smoked Malt, Honey Malt, etc?
 
A table I found a long time ago. No guarantee of accuracy.
Mash theseMashNot these
Any Base MaltAny Crystal Malt, Most Malts that Start with CARA, Most Caramel Malts, Most Malts that Start with CARA, Special B Malts, Roasted Malts, Chocolate Malts, Roasted Barley, Dark Wheats and Carafa Malts
UK Pilsner 2 RowYesCaraFoam
PilsenYesCarapils
Flaked OatsYesBeechwood Smoked Malt
Malted OatsYesCrystal 10
Flaked CornYesCrystal 20
2 Row MaltYesCaraRed
Flaked BarleyYesMelanoidin Malt
6 Row MaltYesCaraVienna Malt
Golden PromiseYesBiscuit Malt
Bohemian PilsnerYesCrystal 40
Irish Stout MaltYesCaraMunich I
German WheatYesSpecial Roast
White WheatYesCaraMunich I
Wheat MaltYesCrystal 60
Crystal 80
Flaked RyeYesCrystal 120
Rye MaltYesExtra Special
Acidulated MaltYesCaraAroma
Red WheatYesSpecial B
Oak Smoked WheatYesChocolate Rye
Maris OtterYesRoasted Barley
Kolsch MaltYesCarafa 1
Pale AleYesPale Chocolate
Vienna MaltYesChocolate Malt
Cherrywood Beechwood Smoked MaltYesChocolate Wheat
Light Munich MaltYesCarafa II
Golden Naked OatsYesDark Chocolate Malt
Munich MaltYesBlack Patent
Munich 10 (Dark Munich)YesBlack Malt
Red XYes
Abbey MaltYes
CaraHellYes
CaraBelgeYes
Amber MaltYes
Honey MaltYes
Aromatic MaltYes
Victory MaltYes
Brown MaltYes


What are the column headings supposed to actually mean?

For example, it says Flaked Corn in the "Mash" column. Does "Mash" mean it "can't be steeped?" If so, fair enough, but... it also says Beechwood Smoked Malt in the "Not These" column. Does "Not These" mean "okay to simply steep?" If so, that's wrong, and in fact Beechwood Smoked Malt is a base malt. I can't decipher it.
 
So I guess a side question is: What is the impact (both positive and negative) of steeping a grain that should be mashed? Can an extract brewer add some character from steeping a grain like Aromatic, Golden Naked Oats, Smoked Malt, Honey Malt, etc?

The positive is you'll get some flavor and color. The negative, as stated before, is potential haze and shorter shelf life.

  • Biscuit Malt (23 SRM)


I'd have to disagree with that. There's nothing special about biscuit, as compared with other lightly roasted malts, that would make it more suitable for steeping.
 
I am doing some research into partial mashing vs steeping...
I'm assuming that you have seen Testing fermentability of crystal malt (link), but it may be new to others reading this topic.

Are you going to look into wort pH differences (if any) from steeping vs mashing?

Why would a grain like Chocolate Malt yield 28 points when mashed and only 15 when steeped?
Could be a "typing error" in the original table. Or the above article may have a process to confirm the values.

Are there guidelines or data from a malt spec sheet that can be used to determine if a light colored specialty grain is a good candidate for steeping or if it should be mashed?
I haven't found the info in spec sheets. Some maltsters will have the information in articles at their web site (example link).
 
if it were me, i'd just mash everything to be safe? toss in ~4oz pale malt, call it a good steep?


hey there you go!!! boil up some white flour so that it's a semi rigid paste, then 'test' your malt to see if it will liquify it...? maybe? that would prove it has the enzymes, and boil it and use titratable iodine to see if the malt needs a mash....

you could probably even use a known amount of vitamin c in the titration to see just 'how' important mashing would be....
 
Are you going to look into wort pH differences (if any) from steeping vs mashing?

pH with partial mashing is an interesting area (as well as grain to water ratios). I suspect that the common partial mash of throwing 1 lb of grain into 3 gallons of water is a terrible environment for conversion to happen. The mash might be too thin to support conversion and the pH is bound to be rather high. For a light colored grain bill, a partial mash using a more "standard" 1.25 to 1.5 quarts to lbs ratio will at least pull the pH closer to the desired range. Some calcium salts would bring the mash into ideal ranges. I could see where acidulated malt would be useful for partial mashes.

I haven't found the info in spec sheets. Some maltsters will have the information in articles at their web site (example link).

Interesting. They list Carapils which I see conflicting info about. I would not have expected to see Victory, Special Roast Malt, and Extra Special Malt on a list of grains that they recommend for steeping.
 
Are all the enzymes in DME and LME dead or can you mash your non-steeping grains in that?. I am guessing not just because I got a free extract kit the other day for a Smashing Pumpkin Ale and if I wanted to use real pumpkin I should have ordered some 6-row malt to mash the pumpkin in.

Are all the enzymes killed in making the LME and DME?
 
Well darn. Needless to say I did not get the grain needed to mash the pumpkin so all I have is a Spiced Smashing Ale but it is good none the less
 
When malt is put in the roaster at 45% moisture and brought to 143* for a time , then 158* for a time (crystal malts), each grain is like a mini mash tun and is getting its starch converted,these only need steeping.

when malt is taken at finished moisture content and brought up in temp in the kiln is what is considered a high dry malt and must be mashed.
 

Ah. This list...
  • Carapils® Malt (a unique dextrine malt)
  • Victory® Malt
  • Special Roast Malt
  • Extra Special Malt
  • All Caramel Malts (Crystal malts)
  • All Dark Roasted Malts
  • All Roasted Barley
I would disagree with Victory and Special Roast, for exactly the reason that Briess mentions on that same page... "It is not recommended to steep Base Malts, Pale Ale Malt, Munich Malts or other malts with a mealy endosperm because starch could be extracted which would interfere later in the brewing process."

To me, it's confounding that they would say that and then include a couple of mealy, starchy malts in their steepable list, on the same page, no less. If you look up the malt analysis for Victory, they list it as "100% Mealy." That's about as mealy as it gets. :)
 
From another perspective:

Just add 3lb of base malt to your grain bag, partial mash at 150F for an hour, and you don’t have to worry about the “is this a steeping grain or do I need to mash” question.

That was my first step in transitioning from extract brewing to all grain.
 
Brewing some beers to play around with the results of partial mashing...or the downsides of steeping flaked grains. It is pretty common to see recipes that call for steeping flaked oats so I figured I would give it a try.

Probably not a big surprise, but steeping flaked oats + flaked wheat + crystal for 30 minutes leaves lots of starches as seen by an iodine test:

Partial Mash 1.jpg


But swapping out the flaked wheat for malted wheat for a 30 minute mash resulted in a lot less residual starches (and a few more gravity points in the wort):

Partial Mash 2.jpg
 
A table I found a long time ago. No guarantee of accuracy.
There is a similar table in Brewing Classic Styles. Some of the malts in the table you posted are newer (and not in the table in the book). The book also has some discussion on the table that may be of interest.

I am doing some research into partial mashing vs steeping...
There are a couple of books that may be helpful to your research:
  • Brewing Classic Styles
  • Methods of Modern Homebrewing (Colby) has a chapter that includes sections on process for brewing using 1) "extract plus grains", 2) "small partial mash", and 3) "large partial mash".
  • Modern Homebrew Recipes (Strong), Appendix C ("Working With Extract Recipes"), has a section on mini-mash
The idea of "small" vs "large" partial mash is something that would be worth exploring. The books also hint at simple water adjustments.

One source for additional insights into small & large partial mashes for 5 gallon batches would be brewers who brew either 1 gal or 2.5 gal all-grain batches.

Just add 3lb of base malt to your grain bag, partial mash at 150F for an hour, and you don’t have to worry about the “is this a steeping grain or do I need to mash” question.
There is value to being able to properly "steep" vs properly "partial mash" for brewers who choose to brew with DME/LME.

One can also steep malts while the water is heating to 170F. This saves 30 to 60 minutes during the brewing session. Methods of Modern Homebrewing (Colby) has a couple interesting variations on steeping.

How to tell if a grain has convertible starches?
If one can find a product spec sheet, "mealy" & "glassy" appears to answer the question.

It is pretty common to see recipes that call for steeping flaked oats so I figured I would give it a try.
Going forward, this should be useful some people here, as it will offer more evidence that the problems that come from brewing with "extract" are not related to fresh DME or LME.
 
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I don’t know what “properly steep” or “properly partial mash” mean. There isn’t a huge mystical step from one to the other. One is basically a dissolving & rinsing process and the other is a biochemical & rinsing process.

What I described is a PM-BIAB. Sure, efficiency can be improved with stirring and sparging, etc. What I described should get anyone about 60% efficiency and solves problems for people who want to use low Lintner value grains in their extract beers.
 
@Beernik : this topic may have some ideas on "proper" when talking about steeping, mini-mashing, or partial mashing. There probably isn't a "one size fits all" definition (e.g. "quick and easy" vs "short and shoddy" vs "compromise elsewhere").

:mug:
 
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I have been looking closer at some of the extract, steeping and partial mash info in various books that I have. I see lots of books and recipes that make me understand why brewers are confused about steeping vs mashing and about what grains can/should be steeped.

"Simple Homebrewing" from Drew Beechum & Denny Conn seems pretty weak on this area. The first recipe in the extract section is an American Blond that calls for a "Steep/Mash" of 0.5 lb of Carapils and 0.5 lbs of Aromatic Malt. I don't see any effort to differentiate steeping and partial mashing. The section on converting all-grain to extract is very vague on this area ("These [flaked oats and flaked wheat] are fine to steep if you're steeping between 150F and 160F and have a little pale malt in the mix").

"Modern Homebrew Recipes" from Gordon Strong has an appendix on extract brewing that has some solid advice. His general advice is that you might want to eliminate small additions of character malts and do your best with the common extract that is available (usually pils, golden, pale ale, and Munich), or do a mini mash. He warns about steeping starchy grains, but says that steeping a small amount might be okay if you value the flavor addition more than the potential issues with the extra starches.

I am surprised how little space in "How to Brew" (4th Edition) is spent on partial mashing. I look to John Palmers methods for brewing extract beers with steeping grain as setting some of the best practices. All I find is a 1/2 page call out in the all-grain brewing section with one example partial mash recipe option. He seems to recommend mashing in 3 gallons of water, then adding the extract late in the boil. Flipping through the recipes in the book, I see some extract ones that call for steeping grains like Victory and Brown malt.

"Brewing Classic Styles" has an appendix on Partial Mashing that is decent. I also see lots of the extract recipes in this book that include steeping grains like Victory, Biscuit, and Brown malt. There is a stout recipe that calls for steeping 2 lbs of Flaked Barley! The extract Oatmeal Stout calls for steeping 1 lb of Flaked Oats.
 
Hey,I got an idea. If you steep whatever grains you have in 150* liquor, then IF there are convertible grains ,they will be MASHED!
Let's get rid of the moniker Partial mash and go with Mini mash,then all will be converted. How about it want to be a convert?
 
Hey,I got an idea. If you steep whatever grains you have in 150* liquor, then IF there are convertible grains ,they will be MASHED!
Let's get rid of the moniker Partial mash and go with Mini mash,then all will be converted. How about it want to be a convert?

The issue is that you need to also provide a source of enzymes. This usually comes from a light colored malted grain (pilsner, pale ale, malted wheat, vienna, etc.). If you just steep a load of Victory + Honey Malt + Brown Malt in 150F water, no conversion will occur. In my mind, the terms "Partial Mash" and "Mini Mash" mean the exact same thing

You could always just add some base grain into your "steep" to make it a "mash", but mashing adds more complexity with temperature, time, pH and grain to water ratios.

When I started brewing, there seemed to be such a huge divide between the complex equipment needed to mash and the simple process of steeping. To me it has always been fairly clear how to tell the difference. The popularity of BIAB has really complicated the matter since both just look like you are soaking grains in a bag in warm water. I am also finding that many recipes and "reliable" sources do a terrible job of separating out steeping vs mashing.

Two good articles on the difference between steeping and mashing:

https://homebrewanswers.com/steeping-vs-mashing-grain/
https://byo.com/mr-wizard/what-exac...basically-involve-soaking-grain-in-hot-water/
 
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