Service Communautaire d'Information sur la Recherche et le Développement - CORDIS

Evaluation of novel endoxylanases and identification of an uninhibited endoxylanase showing superior performance in Solfibread-making

Project foreground work had shown that the TAXI type inhibitors from cereals significantly affect the functionality of microbial xylanases in in-vitro assays. Furthermore, the inhibitors seemed to effect the xylanase functionality in bread-making applications too. To elucidate this effect further, Danisco included five Bacillus xylanase variants in the SOLFIBREAD project. These xylanases had been developed using site-directed mutagenesis and reflected a broad range of xylanase inhibitor sensitivity from highly inhibited to completely uninhibited. Bacillus xylanases were chosen, since they are only inhibited by TAXI type inhibitors - not XIP type inhibitors.

Evaluating the xylanase variants in a dough model system, showed some highly interesting results. We can conclude that the TAXI type inhibitors from cereals in vitro - but also in dough systems - significantly affect the Bacillus wildtype xylanase and three of the five new variants brought into the project by Danisco. Due to the difference in inhibition sensitivity between the xylanases, the xylanases affected the dough rheology differently.

The novel un-inhibited xylanase, brought into the project by Danisco, stabilised the dough system significantly more than the other xylanases. Furthermore, the novel uninhibited xylanase was able to solubilise significantly more water un-extractable arabinoxylan, creating more soluble fibres in the final product, than any of the other xylanases.

Due to the mechanism described above, the novel un-inhibited Bacillus xylanase was able to optimise the Wheat-Barley flour - making it possible to produce consumer acceptable bread products.

Reported by

Danisco A/S
Edwin Rahrs Vej 38
8220 Brabrand
See on map