The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Why does sugar affect gluten development?

nicodvb's picture
nicodvb

Why does sugar affect gluten development?

Hi,


recently I'm doing lots of croissants:-)  and I'm experiencing lots of negative effects on gluten development by sugar: while without sugar the dough hydratation can get as high as 60%, with little sugar added  (20%) -whether dissolved in water or added to the flour- I can barely reach a 50% hydratation.


Can anyone explain the underlying physics? Is there any countermeasure other than adding flour?


Not that adding flour or changing hydratation is a problem, but I'm really curious to understand why sugar has such a negative impact on the structure of the dough.


Thanks.

ananda's picture
ananda

Fantastic question Nico!


As a forward note, you may care to ponder that my croissant formula is sugar-free!!!


Anyway, the effects of sugar are as follows:


Sugar causes flow!   It also tenderises the dough.   So it acts as a kind of improver in the way that protease, or, l-cysteine might do; ie. it softens the protein.


Let's get competitive now: Water..there's a battle for it!   Sugar wants water, then both protein and starch in the flour want it too!   And that's the ranking.   Sugar will always win out.


If I'm making scones, or, a sweet paste, I always dissolve the sugar into the liquid.   I do this to enable the sugar to take up all the liquid it wants first.   That way there is sufficient leftover for the flour.   It's very similar to the autolyse concept.


Is that good for starters?


Best wishes


Andy

nicodvb's picture
nicodvb

infact when I read your recipe I wondered why sugar wasn't there. When I made my sweet croissants I said to myself "aha, that's why!". Sometimes you have to touch it with your fingers to understand something.


I see, so in retrospective I think I made the right choice when I decided to keep the dough very slack and relied on the cold to laminate it.


Thanks, Andy. Very useful as always.

ananda's picture
ananda

But!


Isn't it a bit of a buggar to laminate?   I'm not envious of that.


To me the best croissants are made from doughs subjected to sensitive laminating technique.   How high is your sugar level anyway [% on flour]?


I'm just looking over Michel Roux's recipe in Linda Collister's "The Bread Book", published back in 1993.


He has 100% UB white flour, 8% sugar and 62% water.


I'm not sure I would want to even consider going over 10% sugar; really 8% should be your max.   Beyond that level it will start to hinder ferementation rate as well as soften the dough excessively.

nicodvb's picture
nicodvb

was far too much for the poor dough. The first time I even used 33%, you can imagine how it came out ;-)


I have to say that even though it was slack once it was cold enough it wasn't at all difficult to laminate, but of course the croissants  didn't come out as well as I hoped... if I can call them croissants...

Mini Oven's picture
Mini Oven

Mini

ananda's picture
ananda

Maybe you've got too much of a sweet tooth?


Better look to a more healthy option in future I suspect?


Remember if you use fat @ 25% of the dough, you can still say they are 75% fat free!!!


Best wishes


Andy

ehanner's picture
ehanner

I've been following along here wondering about the effect of sugar in the dough.


The reasons for using sugar in a laminated dough would be to aid the dough in caramelizing earlier and helping the over all color, yes?


At 8% you would barely be able to taste it and since the dough is cold, the bacterial activity is low so the sugar isn't becoming part of the food supply to any great degree, Yes?


The prior are intended to be questions to help me understand why there would be a need for sugar in a laminated dough.


Eric

subfuscpersona's picture
subfuscpersona

Perhaps not, since it is a liquid. But I have learned that, like sugar, honey is hydroscopic.


Eagerly awaiting your answer, oh gurus.


Thanks - SF


 

ananda's picture
ananda

Hi Eric,


Thanks for jumping in with these questions.


Maybe an inital way to look at it is to give an answer to what is your fundamental question, and my thread header.


Sugar tenderises the dough.   It softens the gluten, inducing flow.   So it acts like a natural dough conditioner, in the manner of protease, or, l-Cysteine, creating extensibility in the dough, thus inducing flow.   There will be too much flow at 20% sugar.


I would argue sugar was added for flavour and structural reasons primarily.


Colouration; yes, sugar will bring colour to the dough, so too will the egg glaze.   Too much colouration is not so good.   My experience suggests laminated paste performs better in a hot oven.


Lastly, bacterial activity.   A banana when one is feeling a bit peckish will act as a kickstart and make one feel refreshed and ready to go.   A blow-out meal in a fancy restaurant is unlikely to induce anyone to go for a 3 mile run.   Same with high sugar in dough.   Yeasts don't like being over-faced.   I take what you say about the cold environment; but doesn't that make it even more important not to compromise yeast activity to the point where there just isn't any?   The ferement could be killed off altogether, which would be catastrophic.


By the way, if you carried out a taste test, side by side, I reckon you would quite clearly be able to discriminate between a sugar free and an "8% model".


This is a personal opinion, and I don't want to be shot down in flames for it.   If you don't agree, that's fine, but I'm not up for an arguement about who's right....ok, I believe we have far too much sugar in our diets, and our palates have adjusted to very highly sweetened products.   This does all our health no good whatsoever.   I willingly acknowledge that I don't have a particularly sweet tooth.   I'm very grateful for that when I see the mass of extra sweet confectionery laid before our eyes by the big confectionery manufacturers.   It's a big scandal to me.


But, Eric, do you think of a croissant as a highly-sweetened product?   Just interested in your view here.   I like to have mine still warm, with a fine cup of strong black coffee [which I don't sweeten], and nothing else [no butter, there's enough in the original dough! no jam either, too sweet!].   So a little sugar is ok, as I do acknowledge the improving effects have benefit.   But high suger?   Yuk!


All good wishes


Andy

nicodvb's picture
nicodvb

I have to confess that I like sweet stuff a lot, (although not overly sweet) and that I added sugar only for taste purposes.


As I learned it's not a good idea, as it's not indulging on so many sugars (that in any case I probably consume going to gym every single day). ;-)

ehanner's picture
ehanner

Nico, I'm with you on having a sweet tooth now and then. But Andy does make a good point that over all, we have been trained to consume way too much sugar in all processed foods. That said, let's be serious. We are discussing a lavish pastry here with 25% butter. It does seem a little hypocritical to be thinking about making a more healthy croissant.


One further comment about sugar. I notice that in AB&P by Suas, his croissant formulas all call for 11-18% sugar. The lowest is for a WW mix and the highest is a formula for hand mixing. I suppose that goes along with what you are saying Andy that sugar helps the dough flow and be more extensible.


Another thing I see in Suas is the use of a small amount of malt. I assume this is an additional attempt at adding to the color at a lower temperature. He suggests 385F in convection.


For me a good croissant is all over golden brown and not overly so. This from SteveB is my perfect example.It should have a nutty flavor from the preferment and  a blistered flaky crust that makes it a mess to eat, wonderfully so:>) I like extra butter but I wouldn't want to ruin the special heavenly flavor with a jam. Yes Andy, strong, black and very hot.


Cheers,


Eric

ananda's picture
ananda

Hi Eric and Nico,


I definitely don't want to be implicated as a pretender to more healthy croissant.   That is not where I want to go.   They are luxury to be treasured!


Do you think the malt flour may be added for enzymatic purposes?


Beyond that, I'm going to be contraversial...again, and admit I find myself not agreeing to the bake profiles you mention from Suas.   I bake at a full 235*C in the deck oven, with a top heat at 7 and bottom heat at 5.   385F reads as 196*C when converted.   That's not hot enough to gain the benefit of full aeration to me.   A rapid bake is more preferable to me; BUT, each to their own on this one.   I've been making these consistently for 23 years now, so it's unlikely I'll be making such radical changes; suger free for me....all the way.


Best wishes to you both


Andy

nicodvb's picture
nicodvb

is giving me some problem with this particular preparation, because heat comes from the back of the oven rather than from top and bottom, ventilated with a fan.


Not exactly the optimal for croissants, is it? Infact I had to resort to fast preheat to 220°C (implemented with a combination of grill and convection) and continue baking at 220° for 15 more minutes. With all other methods either the bottom came out raw or the top browned a bit more aggressively...


Now, at least with this method the croissants came out well cooked and well browned, but i always fear that the cooking time is too long and potentially drying them more than necessary.

ananda's picture
ananda

Long slow bake suits some things, and not others.


I enjoyed an extensive baking session yesterday - just posted on my blog.


My oven worked flat out day long, and behaved itself pretty well too.


BW


Andy