The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Today's barley mash bread

sam's picture

Today's barley mash bread


Here is today's barley mash bread.   It is a light barley, 18% of the flour is the barley, milled at home.   The rest of the flour is white bread flour.  On evening #1, I made a mash from the barley flour (held at 160-165F / 71-73C for 4 hrs), and stored in the fridge.  Evening #2, I added the mash to white flour and turned it into a soaker, and separately mixed the leaven.  Today I mixed it all together, bulk fermented 4 hrs, final ferment 1 hr, and baked with steam.   It is very tasty.

Here is the formula I used.  All weights are grams:

Total Dough Weight: 950
Total Dough Hydration: 72%
Total Dough Flour Weight: 552
Total Dough Water Weight: 398


Leaven Percentage: 19%
Leaven Hydration: 125%
Starter Percentage: 10% of leaven
Soaker Percentage: 60%
Soaker Hydration: 80%
Mash Percentage: 30% of soaker
Mash Hydration: 250%
Soaker Salt Percentage: 1%
Overall Salt Percentage: 2%

Barley Flour Weight: 99
Water Weight: 248
Diatastic Malt Powder: 1

White Flour Weight: 100
Water Weight: 125
Starter Weight (125% hydration starter): 10

All Of Mash
White Flour Weight: 232
Water Weight: 17
Salt Weight: 3

Final Dough:
All Of Soaker/Mash
All Of Leaven
White Flour: 117
Water: 2
Salt: 8









I am enjoying these mash breads.  They bring a softer, delightful texture to the bread, and good flavor.


Wild-Yeast's picture

Suggest that the mash temperature be lowered to ~ 120 dF for improved conversion.  

Lovely looking loaf.  Appears Scottish...,



Syd's picture

A lovely open looking crumb.  I bet it has a complex, sweet flavour.  What, with all that mash and the diastatic malt and then the soaker.  No wonder you have those large holes in the crumb.  All that food for the yeast:  they must have had an absolute feast.  I know the optimum mashing temperature for rye (to encourage alpha-amylase activity) is in the range of 54-63C but I don't know anything about barely.  Anyway, that is a great looking loaf.


tananaBrian's picture

Looks awesome!  I can almost taste it from here!


(Thanks for sharing!)

sam's picture

Thanks Brian!   It is tasty..   Addictive.   :)

sam's picture

Thanks Syd and Wild-Yeast.    

Scottish bread?

Well, about the temp, I'm just following Reinhart in his Whole Grains book.   Seems it is best to keep the mash around 160F / 71C, with the intention of denaturing the beta amylase in favor of the alpha amylase, but not exceeding 165F / 73C.   Otherwise you run the risk of denaturing the alpha amylase.   Without scientific equipment to verify, I am left with my taste buds.   This barley mash tasted excellent.  Sweet barley flavor. 

I put in an order today for an accurate sous-vide style of temperature controller, planning to connect it with a countertop single-burner range and see if I can get more consistent mash temp.   My current method of using a toaster oven + saucepan works, but needs adjusting every 30 mins or so to keep it in a tight range.  I'm hoping I can put the sous-vide probe directly into the mash and have the temperature controller switch on/off the electric burner as necessary to keep it at 160F / 71C consistently.   We'll see.



Doc.Dough's picture


Depending on which one you get, you can set the parameters of the sous vide controller to make it stable under your particular conditions.

But maybe not - since there is no active cooling the hysteresis can kill you and the constants are non-intuitive while you are learning to use it.

Start off with low gains and a low thermal input as there will be a delay between adding heat and seeing the temperature rise in the middle of the mash (and it could be quite a while which would lead to increased demand for heat which will overheat the outside before the rate constant causes the heater to back off).  Just go slow  until you know what the response will be. Probably want to have an intependent probe near the outside of the mash as well as one in the middle.


sam's picture

Thanks Doc,

This is one I ordered:

There is also the issue of evaporation, I've been compensating by increasing the overall bread hydration a few percentages, that is not an ideal method, I know...  .   I haven't measured evaporation loss but there is definitely some steam that goes out when I remove the lid to measure the temp so far.

In theory, the auberins probe wire part is thin, so I've been thinking of using a normal saucepan w/lid and hoping the probe wire is thin enough, and for any extra gaps, maybe using a hack job to seal it...   like maybe chewing gum!   :-)

We'll see.   Should be better than mucking around with ovens...   my experience so far, I have to keep adjusting the thing every few mins....


charbono's picture

My copy of Reinhart's WGB recommends an initial water temp of 165°, with a post-mix holding temp of 150°.   It's also worth noting that Spiller recommends a holding temp of about 120°.



sam's picture


My apologies, I stand corrected.   My memory was shoddy.  You are right, he does propose the initial temp of 165F of the water, then adding the flour, then setting the oven temp at 150F.  

So, for me, by holding my mash in a 160-165F range, I guess am doing it wrong, or at least differently.   I am also doing it different because I haven't been starting out with water at 165F.   I've been starting it at room temp and then heating it up.    Oh well....

Any particular reason why not hold the mash at 160-165F?   As long as you're not exceeding 170F and denaturing the alpha amylase.. 

Syd's picture

I stand to be corrected, but I think the reason for the initial higher temperature of the water is to offset the lower temp of the flour which will presumably be at room temperature.  The combination of the hotter water (at 165F) with the cooler flour should result in a temperature of about 150F.  150F is then closer to the ideal temp for alpha amylase activity not 165F.  Higher than 175F and all activity ceases. 


charbono's picture

It seems to me that by holding a mash at 165°F you
are allowing very little room for error. 
Just slightly higher, and the alpha-amylase is cooked.


Another reason that the high holding temp is undesirable
is that virtually all of the beta-amylase is denatured.  Now, Reinhart seeks to minimize the
beta-amylase in order to reduce gumminess. 
However, I don’t think he intends to eliminate all of it.  Both amylases are needed for conversion of
starch to sugar because they work on different parts of the starch molecule.

ananda's picture

Syd, you are correct that the water and flour should mix together to form the final desired temperature.

Please forgive me all, but I work metric.   I'll try to use both here.   Alpha amylase is created optimally at a higher temperature [65*C, 149*F] and Beta at a lower temperature [55*C, 131*F].   Additionally, beta prefer a lower pH in the environment than alpha.

Gvz, I would recommend that you alter the mash temperatures to achieve a mix of no higher than 66*C.   My brewing book recommends mash should proceed within a temperature of 60 - 66*C [140 - 151*F], and should not fall without this range at all for the entire process.   You do need some beta activity within the diastase, although it is recognised, as you state, that the alpha amylase is critical to produce.   I believe the idea is to go no higher than this in order to have better balance of alpha and beta, in that most, but not all of the beta will be destroyed.   Any higher and no beta at all can survive.

Best wishes


ps. Forgot to mention, your bread looks absolutely wonderful!

sam's picture

Thanks for the replies about the mash temp.  I am obviously no food scientist, just kind of experimenting around, but if I recall correctly, PR is intentionally attempting to denature the beta amylase because it produces maltose which, if you have too much of it, makes the bread gummy.  I'm not sure what sugars the alpha-amylase produce, I am guessing sucrose, fructose..

Links to this chart has been posted before, I am not claiming its accuracy or anything, but for the sake of argument let's say it is correct:



If the goal is to denature beta amylase, I would think one would want to keep the mash temp at 160F / 70C.   It is unclear to me also, if by hitting a temp of 160F/70C, that all of the beta is immediately denatured.   It could take a certain duration of time at that sustained temp to denature all of the beta.    Once all the beta was denatured, the mash temp could be lowered back down to 150F / 65C and let the alpha keep on doing its thing, at the slightly lower temp...

Well, maybe once I obtain the sous-vide temperature controller and have more precise control over the mash temp, I can run a couple of head-to-test tests and see what happens.   I do realize that by starting my mash at room-temp and heating it up, it will go through the full range of temperatures before achieving the critical 160F/70C temp which denatures beta.   So I will still get some beta-activity before it is denatured.    But it should be easy to run 3 tests:

1.  Heat to 150F / 65C and hold there.

2.  Heat to 160F / 70C and hold there.

3.  Heat to 160F / 70C for a period of time, then lower to 150F / 65C and hold there.

And see if I notice any differences in taste, crumb structure, etc.

I'm not too concerned about any preservation of gluten-forming proteins.  I am assuming "bad things" happen to them, and for things like barley or rye mashes, there's little to no gluten in there anyway...



sam's picture

A little googling around, from wikipedia:

If I am reading it correctly, seems that the alpha amylase in grains makes both maltose and glucose, and something called "limit dextrin".   The beta amylase only makes maltose.    Possibly an excess amount of the maltose is what causes "gummy" bread, which is the intent behind denaturing the beta amylase.  I've only experienced "gummyness" when I have accidentally underbaked a bread, I'm not sure if that is the same thing as "gummy" as a result of too much maltose.

ananda's picture

Hi gvz,

By all means experiment away, and We look forward to reading the results.

But my reading is clear.   Charbono and I do not accept either your recollections, or Reinhart's desire to fully de-nature beta amylase.

The brewing science suggests it is about achieving a balance of alpha and beta, in favour of alpha, for sure, but not at the expense of destroying all the beta

Best wishes


sam's picture

OK, thanks Andy.

Well, I'm not brewing beer, I'm making bread, but all is good.  

Thanks again for the discussion.



ananda's picture

For sure gvz,

but I'm actually not sure there is any difference in the rationale, or, the adoption of the process for either discipline.

On that, I'm happy for further debate

Best wishes


sam's picture

Hello Andy,

Well, I finished doing two rye mashes, head-to-head test.  Both the same: 100 grams flour, 200 grams water, 1 gram diatastic malt powder.   

First was mashed at 73.5C for 3 hrs.  Second was mashed at 65C for 3 hrs.

The 65C mash tastes better to me.   You were right.  :)



Reed's picture

Your bread looks beautiful, those big holes are really attractive, I can't wait to try this recipe this week end!

 During my previous trial I just add Malt directly into dough, and that caused sticky for final dough and rubber-like texture in crumb. I cannot wait to try this mash method with hot water to see what this will lead to!

By the way, I cannot have time to feed a sourdough, so can I just use commercial yeast alone with mash and forget about levain?