"Roy Basan" > schrieb im Newsbeitrag
om...
> "Ulrike Westphal" > wrote in message
>...
>
> > Obviously the German soft wheat flours I used before were not suited for
> > high hydration breads.
> German wheats are not that soft, it is just the nature of their wheat
> grain that exhibits weaker gluten quality than American flours.
> Another things if you examine the farinograph curve of the two flours
> you will notice that American flours of the same protein and ash level
> had higher mixing and fermentation tolerance; hence are more robust
> than most European flours in baking. The European flours are known
> for their lesser hydration characteristics as well as less mixing
> tolerance if compared to north American flours.
> But IIRC even in this high hydration dough some folks here succeeded
> in using the American untreated (all purpose flour? ) for such
> watery doughs; meaning that flour protein is not the main issue but
> the nature of the wheat protein of the flour itself.
> The simplest solution with such lesser performing flour would be...
> Adding vital wheat gluten to the type 550 german flour would boost its
> hydration characteristics.Remember a 1% addition of gluten to the
> flour will raise its protein content by 0.70-0.75%. Therefore if your
> target is around 13% flour incorporating about 3% wheat gluten powder
> to an 11% protein flour will simulate the protein level of the King
> arthur flour that succeeded in your trials.
> BTW, type 1050 indeed contains higher protein but higher ash level
> that is attributed to branny particles that can contribute to dough
> weakness due partly to the abrasive action of such coarse particulate
> matter on the gluten fibrils. Therefore the gluten content is indeed
> higher but interaction of the extraneous substances such as wheat bran
> and also active wheat germ components, also contribute to dough
> weakness. The latter by exuding glutathione that will weaken the
> gluten as well resulting in pan flow in the latter stage of the
> fermentation process
> Schematically it is disulfide bond- sulfhydryl bond exchange( -S-S-
> and SH)
> 2GSH + P-S-S-P = P-S-H..P-S-H + G-S-S-G
> where GSH= glutathione
> P-S-S-P = wheat gluten
> P-SH...SH-P= weakened gluten
> G-S-S-G = oxidized glutathione taking away some of the the
> strengthening disulfide bonds -S-S- out in the adjacent gluten fibers.
> The result will be gluten weakening and more pan flow( the dough that
> will not hold its form).
> These chemical reactions will not severely affect American flours due
> to the nature of its gluten quality. Further from the point of
> organic and physical chemistry the nature of the amino acid sequence
> of the American flour is slightly different than European flours and
> the intermolecular/intramolecular bonds that make up the tertiary
> protein and quaternary protein structure is slightly different;
> meaning that conclusively you cannot equate protein quality of the
> two flours as identical in performance .These minor difference can be
> modified by fortification of the weaker flour with gluten powder so
> that you can attain your target product performance.
> Roy


Thanks for your detailed explanation. I just mixed 500 g Type 550 (11 %
protein) with 20 g gluten flour (80% protein), so this mixture contains
13,7 % protein. The next trial has begun and tomorrow I know more...

Ulrike