Phenolic compounds and free sulfhydryl groups in whole grain wheat flour modified by xylanase

Abstract

BACKGROUND: Knowledge of the structural behavior of dough elaborated using whole grain wheat flour (WGWF) and xylanase is fundamental for the elaboration of products with high nutritional content, especially when the particle size of the flour is altered. In the present study, we investigated the effect of varying concentrations of xylanase on the formation of dough with different particle sizes of WGWF. RESULTS: Phenolic compounds, fibers and proteins are the components that undergo the most change and interfere with dough formation. A small particle size favors the extraction of phenolic compounds and dietary fibers, resulting in a high-quality dough. There was a protective effect of the stable phenolic compounds on the gluten network. An increase in fiber degradation and a decrease in phenolic compounds was noted as the xylanase concentration increased. Although xylanase increased free sulfhydryl (-SH) groups in gluten, there was no change in dough formation and dough stability with an increasing xylanase concentration. CONCLUSION:The WGWF with a smaller particle size does not contribute to the loss of quality in dough elaboration. The addition of intermediate amounts of xylanase (20 mg kg −1 ) in samples with a particle size of 158 m can be used to improve dough characteristics.

Effect of Bran Pre-Treatment with Endoxylanase on the Characteristics of Intermediate Wheatgrass (Thinopyrum intermedium) Bread

“…This was not the case in our sample set, and xylanase pre-treatment increased thiol accessibility as well as loaf volume. A similar result was obtained for whole wheat gluten to which xylanase was added [ 60 ]. Moreover, the accessible thiol concentrations were affected by flour particle size [ 60 ] and future work could assess how particle size (distribution) of IWG influences network formation in general and the effect of enzymatic treatments in particular.…”

“…A similar result was obtained for whole wheat gluten to which xylanase was added [ 60 ]. Moreover, the accessible thiol concentrations were affected by flour particle size [ 60 ] and future work could assess how particle size (distribution) of IWG influences network formation in general and the effect of enzymatic treatments in particular. The fact that the highest concentration of accessible thiols was found for dough made with pre-treated bran and ascorbic acid was unexpected, as its oxidation product dehydroascorbic acid can oxidize and thereby remove glutathione [ 40 ].…”

The effect of tempering on protein properties and arabinoxylan contents of intermediate wheatgrass (Thinopyrum intermedium) flour

“…In our sample set, accessible thiol concentrations displayed significant positive correlations with protein solubility in buffer ( p < .05, r = 0.472) and negative correlations with protein solubility in buffer containing urea and DTT ( p < .05, r = −0.549). Concentrations of cysteine were shown to be higher in wheat albumins and globulins than in gluten‐forming proteins (Lambrecht et al., 2017), and more thiol groups are presumed to be present in whole‐grain flours (Both et al., 2019). Thus, the reduction in accessible thiols in tempered flours can be taken as another indicator of a greater extent of bran removal.…”

Effect of yerba mate (Ilex paraguariensis) leaves on dough properties, antioxidant activity, and bread quality using whole wheat flour

“…Total polyphenols were extracted from YM as described by Asolini et al (2006). For the free polyphenols in flours and bread, we used the extraction method described by Both et al (2019). Prior to extraction, the breads were lyophilized for 48 h and then ground to pass through a 30 mm mesh sieve (Ning et al, 2017).…”

“…This is probably due to the fragmentation of the leaf cell walls during milling, which increases the contact surface area. The contact surfaces will possess exposed hydroxyl groups from phytochemicals and increase the binding (absorption) of water (Both et al, 2019). WA is critical in bread making as, according to Ma et al (2019), a higher water absorption in flours will aid in avoiding retrogradation and increase dough yield.…”