Mash vs. Water Roux

Hi Chuck,

A mash would usually involve holding the temperature at c.60 - 66*C for a period of time in order to encourage amylase activity and convert starches to available sugar for the yeast.   Water level to flour seems to be lower than that used in the roux.

Mashing is a brewing concept, first and foremost.

Other posters will know more about the water roux than I do.

Best wishes

Andy

I have used the water water roux method for my sandwich bread. It provides softness and moisture in the crumb. If you want a "fluffier" texture and still want homemade flavor in your bread, a water roux works nicely for that. When I was researching how to do the water roux method, some sites described holding the water roux at 160F for 4 hours. I didn't know why they did that as there was no explanation and took the easy way by just heating to 160F but not holding it there. Just recently, here on TFL, a post described the enzyme/sugar part of why that is done. It must become a very sweet custardy roux that gives a loaf good sweetness and flavor. I may have to devise a way to do this.

So, I guess if you are just looking for a softer,moister crumb that bends and doesn't crack as easily, a water roux can be used. As to how that is done, I simply take 1 tbsp of the measured flour and 5 tbsp of the water and microwave them for 10 sec bursts and whisk in between. When it is a nice custardy texture and reaches 160F, I cover and cool to room temp. Then I just mix in when I am mixing the dough.

I have wondered if adding rye flour and extra water to allow it to "gel out" would be about the same. I'll have to do a comparison bake sometime.

If I understand correctly, water roux is gelated starch (Emily Buehler quotes Harold McGee in saying that the correct term is gelating and not gelatinizing).  This starch retains extra water which helps to make the final bread fluffier.  I believe that it serves the same function as polysaccharide additives sold as enhancers.  Water roux is made with flour, the more refined the better.

Mashing on the other hand converts starch into sugar.  Mashing is usually done with whole grains.

Hi MangoChutney,

I think it is important to differentiate between gelatinisation and mashing here.

I'm not really sure why the water roux process stipulates the temperatures quoted by clazar123.   My experience of steeping flour in hot water is that the hotter the mix temperature, the more successful the starch gelatinisation is.   I always use boiling water at 120% on flour  if my key purpose is to achieve maximum satrch gelatinisation.   This will give a mixed temperature well in excess of the 60 - 66*C ideal which is used for the mash process.

To clarify, in brewing, the grains have been germinated and then cracked open to a specific degree in the malting process.   It is sold in home brew shops as "crushed pale malted barley" here in the UK for use in beermaking.   It is, as you note, the whole of the grain that is used.

Best wishes

Andy

Sounds like you found the same sites I found when researching this. I haven't sorted it out to any great detail, yet. For simplicities sake, I make the water roux in the microwave and just make it a really custardy,smooth mix. It seems to soften the crumb and make it more flexible so I never went further than that,yet. I am interested in what comes of this thread.

How do the brewers here hold the mash at 160 for 4 hours? Crock pot or crock pot to heat a water bath at 160 with a bowl of the "roux"? Kind of a double boiler?

From what I can tell from various recipes, a water roux is an extreme form of scald or gel. It is extreme in its high hydration (up to 500%) and high initial water temperature (at least simmering and often boiling). Starch granules are burst. Because of the high temp, all proteins are denatured, including gluten and enzymes. Since the gluten is gone, only a small portion of the flour is treated, at most 10%. Although some of the starch will be converted to sugar when combined with the remaining, enzyme-containing flour, the principal purpose of the roux is textural.

In a mash, somewhat lower initial water temps are used (165°F max, depending on recipe). Temp is carefully controlled and declines with flour mix. The lower temp allows alpha amylase from whole grain or malt to survive, as well as much of the gluten. However, protease is denatured. The pot is kept warm for several hours to allow maximum alpha amylase activity in converting gelled (damaged) starch to sugar. Since much gluten survives, a larger portion of the flour can be treated, up to 50%. For more mash info, see Monica Spiller at sustainablegrains.org, or Reinhart’s Whole Grain Breads.

Hi charbono,

your reply to Chuck is mainly in line with my understanding.

I don't follow the water roux, or tangzhong method as such, but I do use a "boil-up" quite frequently, where I would add water on a rolling boil to flour at 120% on the flour weight.   That flour should be a maximum of 20% of the total flour.   This is because of the de-naturing which you mention.   The very high mix temperature cooks the flour, as the starch molecules burst and enable the take up of the maximum possible amount of water - gelatinisation.   Protein is de-natured and all enzymes are destroyed.   The process is a difficult one in a commercial bakery where it can involve transporting 30L of boiling water to a mixing machine.   In the home, the process can be done with a kettle and use of the stove top.   All that is needed is to cook with care.   For rapid cooling of the mixture, you can place in a mixer and beat very slowly with the paddle for 20 minutes.   Alternatively, very lightly oil a work surface and spread the gelatinised mix thinly over that surface and cover very lightly with a plastic sheet.   Avoiding condensation is really the key, as that just dilutes the gelatinised mix, hence affecting the water absorption figure in whatever recipe/formula you have calculated.

In the mash, I add water at 250% on the flour, with the flour portion remaining at 20% of the total flour in the bread formula.   I add the water at 74*C to give a combined mix temperature of 60*C when mixed with the flour.   I then hold the mash at between 60 and 66*C for 4 hours.   In practice this is not hard to do, although careful monitoring of the temperature is required, and it is important not to get over 66*C.   The means to do this involve insulating the pan well with a blanket, or, holding the vessel in a very low oven.   Obviously a well-fitting lid is required for the pan.   Again the cooling process needs to involve neither water loss from evaporation, nor gain from condensation.

Actually the close temperature range is needed for the efficient activity from 2 enzymes, these being alpha and beta.   Whilst alpha can tolerate a higher temperature, beta cannot.   It is the beta amylase which further breaks down the sugars for the yeast to work from when added to the cooled wort.   Reinhart is generally good on this, but you will need to refer to brewer's texts for more detail.   The book I use is a UK text, so there is little point me quoting it as I doubt you could find it in the US.   For those in the UK interested, however, I use Dave Line's book the "Big Book of Brewing" [AWB: Poole 2004, originally published in 1985].

Hope this clarifies it all for you

BW

Andy

A little more of the science:

http://www.realbeer.com/jjpalmer/ch14.html

Thanks charbono,

the link gives very similar info to that from Dave Line, and the chart is identical.   As you can see, the temperature of the mash dictates the activity rates of the alpha and beta amylase, critical to the extraction of fermentable sugars for the yeast to work on.

BW

Andy

I have enjoyed all of this information here and now have a question, if I may, that is kind of related so I am thinking I can ask it without hi-jacking this thread...

 I have baked with mashes before when following formulas by PR and Dan Leopard.  Neither of the mashes involved added salt.  I know a mash isn't a soaker due to the process involved in creating it but it is similar in that it is wet grain; I know when I do use a soaker - room temp. or refrigerated - there is salt added to slow down fermentation.

While reading this thread it dawned on me that no salt is used in a mash/scald because the enzymes that would ferment the grain have been 'killed' off.

I just wanted to check out if my logic is correct here before I assume something that may well be incorrect.

So....

1.  Soaker gets salt because it has enzymes intact that will start to ferment too quickly without it.
2. Mashes/scalds do not utilize salt as enzymes that may be problematic have been done away with.

Thanks for helping me understand more about the science behind the loaves :-)

Janet

Hi Janet,

You can legitimately view a mash as a type of soaker; one that is dependent on storing at a certain temperature in order to maximise potential sugar content which is available for the yeast to turn into alchohol plus CO2.

The inclusion of salt in the soaker is simply to retard enzymatic reactions.   This could seem to be counter-productive in a "mash".   However, my understanding is that salt will retard the protease enzyme reactions, but not so with amylase.   If this is the case, then salt could still be included in a mash formula.

Specifically, the answers to your 2 questions:

1. Salt is used in a soaker, as you have described, in order to slow down the protease enzymatic reactions, so the structure remains strong when at final mix point.

2. The primary purpose of a mash is to encourage amylolitic reactions, which salt has little effect on.

Hope this makes it a bit clearer

Best wishes

Andy

I did not realize the salt inhibits protease enzymes but not amylase.   I assumed the salt was added to inhibit the nasties like leuconostoc from taking hold.   After one failed experiment of doing a flour soaker w/no salt at 80-85F, and watching it double in size and smelling foul, I've been adding 1-2% salt to my flour soakers with no problems.  (Also not letting them get above 75F).

The part you mentioned about salt inhibiting the protease is new to me.   That is cool.   I've also been experimenting with mashes recently, but have not added any salt thus far.    Sounds like it would be a good idea to add a bit of salt to a mash that will be used for bread.

Hi gvz,

I'm not sure why you would want to add salt to a mash really.

You'll have to excuse me working in *C rather than F, but let's both be clear that the problems of bacterial infection as you describe, are very unlikely to be a danger when using a mash.   A temperature of 66*C should be sufficient over 4 hours to destroy all pathogenic bacteria.   The temperatures you mention [75 - 85 F], 24 - 29.5*C are in a range wher many bacterial organisms are very comfortable and will reproduce at a dangerous rate.

As for protease reactions, I believe the best alternative is to ensure the mash portion of the total flour is kept at 20% or below.   That way, there is still plenty of gluten strength in the remaining flour portion used.

Try using salt in the mash, by all means, but I have never used it, nor felt the need to.

Best wishes

Andy

Hi ananda,

This could be flawed thinking, but in looking at the enzyme chart posted by charbono (above), it seems the protolytic enzymes would be most active between 45C-58C (?).   Say if you started the mash at a lower "room temp", in a saucepan, then heated it up on a stove-top.  As the temperature of the mash increased, it would go through the range of temps that the protease is most-active, possibly causing it to degrade proteins for gluten, before the protease is completely denatured above 58C.    So having some salt might inhibit that phase.   On the other hand, if you begin the mash by mixing the flour into some water that is already above 58C, then in theory all of the protease would be denatured immediately, and then no need for any salt.

Then again, the chart of the enzyme action also indicates pH level, and the proteolytic enzymes seem to be active at a lower pH (mostly) than the amylase.  (there is a little bit of an overlap).    I haven't been taking pH readings of my mashes....

The chart also says, "Normal Mash pH Range" is higher than what the proteolytic enzymes work at.  So maybe it is not necessary to add any salt to inhibit any protease activity if your mash was temporarily in a temperature range that is optimal for protease, since the pH won't be right for it anyway.

Hi gvz,

The British style of ale uses hot water to make the initial mash, which combines with the grain to produce the magic 60*C.   This is my method of choice, not surprisingly.

Continental mashes use the cooler water system and heat through to 60 -66*C.

BW

Andy

Gelating is used to get fluffy texture, or for low gluten flours without broken starch. (The scald will damage some of the starch, whereas in hard flours the starch is already damaged.) Mashing is used to convert starch to sugar. some breads use both (eg Russian rye).