Shades of Brown

Toast
louiscohen on 18 Jun 2023 at 11:46

If you look closely at the crumb of this Workday 1005 Whole Wheat (Bread, 3rd edition) 

Workday 100% WW w/Walnuts Photos

you can see some different shades of brown; I've never seen that before.  Could it be that the bassinage water wasn't worked in completely; parts of the crumb are more hydrated (and perhaps a bit underbaked) compared with the rest?

I had measured out 10% of the water to use for bassinage, but after 3/4's of the folds recommended for the mix, I grabbed the wrong cup and added more water than I wanted.  So I added some more flour as well, and did more folds than usual after the bassinage.  

Also, do you see any signs of overproofing?  The crumb seems more closed than usual. 

Thanks

They can leach a purplish colour and depending on what flour you're using can cause this effect. Doesn't make it any less tasty though. Although toasting them before adding to the dough has even nicer results. 

As for over proofing it's difficult to tell from the photo. It seems to have bloomed nicely so can't be that over proofed if it is at all.

I had not noticed that before when using this formula.  The dark areas might be a little more moist. 

Good tip on toasting; I'll give that a try next time (I typically bake once a week, alternating whole wheat and rye). 

Thanks

According to Laurel's Kitchen Bread Book (p. 223), walnuts tend to color the loaf a sort of lavender-gray unless they are added just before shaping. Just putting that out there as a possibility.

Edit: Cross-posted.

Thanks, that's probably it.  I never noticed it in previous bakes with that formula, though.  Maybe a different batch of walnuts, or different chopping.

Hi Louis,

I was blocked by a log-in window and couldn't see your photos, but I'll trust the others on their assessment about the walnuts. It reminded me that Cook's Illustrated wrote about this phenomenon a few years ago:

"Theories abound on why yeast breads that contain walnuts (or pecans) turn purple. After reading a paper in the Journal of Agricultural and Food Chemistry, we decided to pursue the one that seemed most plausible: that the iron in flour is reacting with gallic acid found in walnut skins to create a color change.

To confirm this theory, we combined walnuts, water, and (to minimize variables) crushed-up iron supplements from the vitamin aisle and watched the water immediately turn a deep purple. We repeated the experiment with pecans, which were equally reactive, and almonds and hazelnuts, both of which triggered a slightly less dramatic color change.

So why don’t all baked goods containing these nuts turn purple? The answer has to do with acidity and time. The purple tint appears only in an acidic environment, and most baked goods aren’t acidic enough to cause the reaction. But thanks to the acids produced by yeast as it ferments, bread dough does have what it takes. In addition, since gallic acid leaches out slowly, rising bread dough gives time for the effect to happen.

Only tiny amounts of gallic acid are needed to bring out the purple. The tint can’t be prevented completely, but it can be minimized by blanching the walnuts in boiling water for 1 minute before using."

So, time, acidity, composition of the nuts and the flour --- any or all of these things can vary from bake to bake. If you do give the blanching a try, you can follow that by toasting if you like.

My best,
dw

  1. This link should give you access https://photos.app.goo.gl/P49Ur6LL7ExYPLD77 to the photos
  2. You would expect gallic acid would be an issue only in French bread
  3. I wonder if the particular time/temp/hydration of this batch resulted in more acid being produced than in previous bakes.  I think I added more water than usual (accidently) and perhaps did not add enough flour to restore the hydration level.  

1. Same log-in page. Thank you for trying :)  Is the discoloration gray or purplish?

2. Why is that?

3. Possibly. Higher hydration can lead to more acidity, although it's not the only factor.

My best,
dw