The Fresh Loaf

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Pentosans, I presume?

Another Girl's picture
Another Girl

Pentosans, I presume?

Hi Everyone. I mixed a deli rye today (Hamelman's Forty Percent Rye) and as soon as the the flour took up all the water, I could tell something wasn't right. The dough was was heavy, slack, and sticky. I added a bit of flour to no avail. Nor did it improve with continued mixing. It took a long time to develop the gluten. The rye flour was KAF Organic Pumpernickel. Normally, I bake with AP flours from KAF or Central Milling, but I've been using Ceresota recently because my local market has been out of everything else. Shaping the dough was extremely difficult and the dough continued breaking down throughout the proof, as you can see in the photo. I'm inclined to think pentosans are to blame, but have never seen what that looks like. It was just pasty and sticky with no elasticity and no extensibility. No nothin'. It kind of shredded when tugged. Can anyone confirm that this was due to the effects of pentosans or have a guess as to what might have caused it? Thanks and Happy New Year!  –AG

 

Abe's picture
Abe

Call for Pumpernickel? 

Also when using rye, and at such a high percentage, would it be ok to use AP flour? Think i'd prefer to go with something stronger. What category does Ceresota fall into? You talk about it as if it's not even up to the usual AP flour you use. 

It might be a combination of these two things. 

Another Girl's picture
Another Girl

Hi Abe. Here's the thing: I've been baking deli ryes on a more or less weekly basis for more than 20 years. Hamelman's Forty Percent Rye has been my go-to formula for many of those years and I've baked this bread literally hundreds of times. The formula calls for whole rye and says medium rye is an acceptable substitute. KAF calls their whole rye pumpernickel, so that is the correct flour. I've used it for many many years. When I first started making this formula I did use bread flour but I switched to AP many years ago. I don't think Ceresota publishes their protein percentages, but I've used it on and off for many years and have never had a problem with it. I am perplexed as to what the problem might be. I've heard of the dreaded pentosans, but have never seen what an affected dough looks like. Since my original post, I've had another thought: My B&T proofer is getting old and the levain seemed quite warm. Maybe the levain overdeveloped and proteolysis is involved? After slicing the bread, I noted that the crumb is extremely tight and the flavor is more sour than usual. I'm open to any and all ideas.

Ilya Flyamer's picture
Ilya Flyamer

Overripe levain with too much acidity could indeed cause this I think! I don't know that recipe, does it have a high % of prefermented flour?

Another Girl's picture
Another Girl

In this bread, all of the rye flour is acidified, so 40%. I think that could do it. Paul is suggesting thiols and I think he's correct. Due to some imbalance (and too much acidity certainly seems like a possibility in this case), it appears that some unwelcome critters have taken up residence in my starter and now must be elbowed out. Thank you and happy new year, Ilya!

pmccool's picture
pmccool

Pentosans are complex sugars that give rye flour it’s stickiness, along with providing structure.  Thiol compounds can interfere with gluten formation and even break down gluten. 

While I can’t offer help for correcting the problem, it may give you a direction for further inquiry. 

Paul

Another Girl's picture
Another Girl

I think you are absolutely right. Thank you!! I have been reading some of the detailed threads about thiol compounds and it looks and sounds like you are spot on. In terms of correcting the issue, Debra Wink posted a 2-week starter rehab program consisting of small frequent feeds that will commence as soon as I post this.

I'll follow up with results for the benefit of any future users experiencing similar symptoms.

mwilson's picture
mwilson

Sometimes your first thought / instinct is the right one, I see you're in danger of being swallowed up by believing the worst...

If you have been feeding your starter consistently and it has been behaving consistently then, it is more than likely fine. With rye comes its problems and yes pentosans are one or them.

Fact: Pentosans do interfere with gluten formation.

Fact: Actually truth be told this one is opinion, and I don't mean to big myself up here, but it comes from a knowledgeable place, that is to say it's not thiols...

Thiols are functional groups that occur commonly in nature and in gluten proteins, namely cysteine residues. Another way to explain a problem with thiols is to describe reduction, reduction being the opposite of oxidation. In one glance I can see your dough is not suffering from the so called "pesky thiols". A reductive (or thiol rich) dough would be slack slack slack extensible and not be able to hold its shape, like a puddle. What you have is tearing, which is the result of inextensibility. The 40% rye flour bread I made for the community bake suffered from tearing also, it's the nature of rye and its pentosan content!

From that community bake there was a consensus that developing the non rye (triticum aestivum) flour as a separate dough and then incorporate the rye was the way to go... I didn't get a chance to try that myself but I can see that working and certainly the evidence was apparent that such an approach does work wonders...

One more thing, high acidity can contribute to tearing also...


Hope that helps,

Michael

Another Girl's picture
Another Girl

Thank you for taking time to weigh in, Michael. That is certainly food for thought. May I ask another question about pentosans? I’ve always been under the impression that less-than-gentle handling is what causes pentosans to weaken and release water. Since this dough was mushy right from the start and I don’t *think* I did anything differently, what might have caused it to happen? Can high acid hasten the breakdown of pentosans? Or an “off” batch of flour?

Shifting attention now to the possibility of excess acidity: My rye starter is reliable and well-maintained, but it tends to acidify rapidly if not closely attended. As mentioned above, I’ve been seeing signs that my aging proofer is not regulating temps well and, as a result, this fermentation cycle may have been on the warm side. It the one aspect of this bake that I can point to as potentially different or problematic.

Based on Michael’s input, I’m going to modify my plan of action. While I await the arrival of the new proofing box, I’ll give the starter some big feeds to reduce its acid load and then bake another 40% rye. I’ll mix the way I always do so as to test only one variable at a time. For the following bake, I’ll develop the gluten before adding the levain. If those measures don't work, I’ll try re-balancing the starter with smaller, more frequent feeds.

Abe, Ilya, Paul, Michael – Thank you all for your insights on this. I’ll post updates here. Happy New Year! 

mwilson's picture
mwilson

Hello AG. I'm familiar with that often sudden change in consistency that tends with to occur with rye and other flours during mixing but I think cause for concern about how the dough is handled may possibly be exaggerated, especially considering in this case where more than 50% of the total flour consists of common wheat. I'm not convinced this transformative effect is actually detrimental overall. I think the development of a wet and sticky consistency may rather be a sign of hydration and aggregation of the pentosans, but I'm not sure.

I only knew for sure that pentosans interfere with gluten but didn't know to what extent or how, so I decided to do a little reading and sure enough what I observed and understood was confirmed exactly; pentosans impede the yield of gluten and indeed specifically, cause gluten to firm up and become inextensible, that I recognised as the reason for tearing to occur. The presence of high levels of pentosans means dough requires more mixing time to develop the gluten sufficiently which may be counterintuitive as the wet and sticky nature of pentosans gives rise to the fear of overmixing.

Still, like I said high acidity interferes with gluten also, so the effect could be a combination. I understand the logic of high acidity in a pure rye dough but as a fraction in what is mostly a common wheat flour dough the requirement for high acidity becomes less crucial I would say.

From what I can determine, to overcome the negative effect of pentosans it would be best to break them down, and xylanase is the enzyme to do it. In one particular study that enzyme was sourced from an Aspergillus sp.

But in practice the way forward is probably best determined by asking those that bake with rye regularly.

I am wondering if an autolyse or pre-fermentation of the rye fraction is the way to go...


Hope that helps

Michael

Another Girl's picture
Another Girl

Wow, Michael, you've gone above and beyond. I truly appreciate your interest and advice. What you're saying fits with the fact that eventually there was some gluten development; overall, however, the dough quality remained very gluey and heavy so I stopped mixing – exactly as you said.

My starter has had a few big meals now, so I plan to try another bake tomorrow. In an effort to change only one variable at a time, I will mix the same way I have always done it. Hopefully that will help demonstrate whether excess acidity played a role in the tearing. The next step will be to develop the gluten in the white flour before mixing in the rye sour. (Interestingly, all of the rye flour in this formula is pre-fermented, so your thinking on that is in line with Mr Hamelman's.) Thanks again for looking into this, it's truly appreciated. 

Another Girl's picture
Another Girl

Apologies, I'm quite tardy in posting this bake, which was conducted on 3 Jan. I ran the first test bake after giving my rye sour several big feeds to reduce its acid load. An extra 15g of water was added to accommodate an unusually thirsty new bag of whole rye flour, but apart from that, all other variables in my control were kept the same. I should have added more water, but after the last slimy bake, I decided to err on the drier side. I was very careful about mixing at a low speed to keep the pentosans in check.

There were some improvements, but the dough still looked and felt unfamiliar to me. It was heavy and sticky and still had less gluten formation than I've come to expect from this dough. However, the shaped dough did not break down the way it did last time, so that was a big step in the right direction. The loaves were still on the small side as you can see in the photo below. They were not under-proofed, they just didn't expand very much. I'm not great at diagnosing problems like this, but how likely is it that more than one factor was involved? I'm kind of feeling like that may have been the case.

Ilya Flyamer's picture
Ilya Flyamer

Could the fault be with the white flour component? It might be weaker that you are used to for some reason?

This bread looks lovely though!

squattercity's picture
squattercity

Picking up on this thought: perhaps the white flour is stale. You report getting a new batch of rye ... but did you try new white flour as well?

Rob

PS: Ceresota reports its AP flour's protein content as 11.6%

Another Girl's picture
Another Girl

Hi Rob & Ilya! You are right: the last bake wasn't bad, but the apparent lack of gluten and poor rise (compared to my usual results) indicate something is still off. I've baked this bread more or less weekly for years, so I know it well.

I thought of the white flour right off the bat but dismissed it because I've always known Ceresota to be a nice flour. I go through AP too quickly for it to have staled in my cupboard; however, I keep my flour in airtight containers and toss the original packaging, so I can't confirm that the store didn't sell me an old bag. 

My rye starter is still suspect. It gets acidic quickly if not vigilantly attended to. As Michael said, there wasn't much reason to think my starter suddenly went bad, but anecdotal evidence has been mounting that my proofing box might be causing problems. I usually only use it overnight when I'm not awake to monitor it so I've been slow to connect the dots, but recently I've been noticing that it seems warmer or cooler than I'd expect. And it's pretty old.

Thanks, Rob, for the info on the Ceresota protein content. 11.6% should give a perfectly good result, but I have a new bag of KAF AP to use in today's bake. Stay tuned...

Benito's picture
Benito

Certainly a big improvement with respect to shaping AG.  I think the thing to try next time is developing the white dough separately from the rye and giving it a bit of an autolyse.  Then add the rye gradually to the dough, your mixer will be able to handle this well if you choose to use it.

Benny

Another Girl's picture
Another Girl

Thanks, Benny! I agree that developing the AP separately is the next step. I tried it during the community bake and didn't perceive enough of a difference to make the extra step worthwhile. I don't remember autolysing it though, and that might make a difference...

EDIT: Adding that this would also, of course, fend off any misbehavior by the friendly neighborhood pentosans.

Another Girl's picture
Another Girl

So I made two loaves out of today's dough and the dough it was still dense and sticky. BUT... much better gluten development, so that was a win. This rye flour is much thirstier than usual. I added an extra 15g water to the levain and could have gone higher. Today an extra 25g water was added to the final dough. The first loaf looked fine, no tearing that I could see, but the second loaf was breaking apart at the top and sides. The off-flavor seems lessened and the bread is perfectly edible. I won't need to bake again right away, but when I do, I'll work the AP separately and post the results.

Thanks, everyone!

squattercity's picture
squattercity

Congrats! It looks as if things are moving the right way.

There's still this question: why two loaves from the same dough should have different characteristics.

Also: regarding the flavor problem -- was the issue that it was extra sour or somewhat bitter. In my admittedly limited experience, sour would indicate a fermentation issue while bitter would indicate a flour problem.

Another Girl's picture
Another Girl

Two possibilities I can think of as to why one "unknitted" and not the other: The first is that I baked the loaves in succession so the second loaf had a longer proof. The first loaf was loaded a bit early so the second wouldn't overproof waiting for it, but this process does result in a 15 or 20 minute loner proof for the second loaf.  The other possibility is that the second loaf was shaped a bit more tightly. Maybe it was a combination of the two things, but once it started, it progressed rather quickly. 

Regarding the flavor, we found it kind of bitter. Tell me more about this, I am intrigued. Thanks! 

squattercity's picture
squattercity

My understanding of bad flour arises from bitter experience:

  • A brand new bag of Bob's Red Mill dark rye turned my starter dull and gloopy and led to some lame bakes. The problem resolved immediately when I tossed that bag and bought new, fresher, locally-grown rye flour.
  • A brand new bag of King Arthur white whole wheat ruined a miche because the dough developed an annoying bitter undertone that was only heightened after baking.
  • I had to throw out a 5 lb bag of Whole Foods AP flour because the breads it made did not rise right and tasted disgusting -- in this case, cloyingly and artificially sweet.
  • And I had to toss a bag of BRM spelt flour because it smelled off when I opened it.

All of these bags of flour were well within their use-by dates.

So what does this mean? I'm guessing that the problem involved how these bags were stored prior to appearing in the store. That's purely conjecture, though.

Now for the caveat: I have been told by those with much more knowledge than me that it is unusual for AP flour to go bad, as it has less of the oily germ and bran than whole grain, and it's the oils that tend to spoil. And you report you go through lots of AP, so it would be unusual for your flour to go bad. But it can happen.

My resolution, for AP and whole grain alike, has been to buy only small bags from a local milling company here in NY. So far, I've been happy with this choice.

Rob

Another Girl's picture
Another Girl

That is very interesting, thank you Rob! Your post got me thinking that maybe it’s not the white flour that should be suspect, maybe I got a funky bag of rye. Or maybe the new crop is weak, who knows? I was intrigued by your idea, so I called King Arthur. 

The rep was very nice and said she was unaware of any changes in the flour, which I expected as they do make a very consistent product. She suggested mixing at the slowest speed for 5-7 minutes (or however long it takes) till the gluten is developed. Her thought is that the gluten development window is closing quickly, without me noticing the subtle signs of transition. At a slow speed, I’ll be able to observe the changes in the dough. I'm retired and have nothing to lose but some flour, so I will give this a try. Besides, if pentosans are to blame, the super slow mix will accomplish the same thing as the “develop the AP gluten separately” plan, so there is that benefit, too. Then it's just a question of which method works better or faster. Thanks for your insights. –AG

Another Girl's picture
Another Girl

It took a couple weeks, but I finally made another forty percent caraway rye yesterday. I increased the hydration in the levain so it would have a little more breathing room but, despite this, there was very little rise at the end of 14 hours. It was puffy and smelled of alcohol. This did not bode well, but I was determined to proceed. I mixed the dough as advised by the rep at KAF with the dot on the Ank knob at about 2:00. It took about 15 minutes and still didn't feel "normal," but it was far less sticky than the last few bakes. It rose well in bulk and so-so in the final proof. Not much oven spring. The crumb was maybe a little heavier than usual, but not bad. Unfortunately, the bitter flavor was back with a vengeance. My husband said it gave him heartburn. Later, my daughter stopped in and asked why the crumb was so dark. That sent me off in search of old crumb shots to compare it to. (The bread on the left was yesterday's bake, the bread on the right was from a year ago). I just don't know what to make of all this. At least the dough isn't breaking anymore...

Tonight I'll mix a levain for a bread that doesn't use any rye flour (except what's in the starter) and see what happens. 

Another Girl's picture
Another Girl

This weekend, I baked up a Don’t Be a Bread Hostage (aka Jail Break) bread from the KAF site. No rye flour was used except for 8g in the starter. The bread isn't going to win a blue ribbon at the county fair, but it's fine. Completely fine. I’m increasingly convinced that a flour problem caused all these issues (weakness/pentosans, off-colors and off-flavors) and may be having an undesirable effect on my starter. I tossed out the last of that rye flour and fed my starter today with flour from a newer bag. The consistency seemed more normal, to the extent one can judge these things from a 20g sample. I’ll do one more test bake of the Forty Percent Caraway Rye after this and, hopefully, wrap up this exploration.