2001 AACC Annual Meeting Charlotte, North Carolina October 14-18, 2001 Charlotte Convention Center

Within the baking industry, it is well known that the functionality of a given xylanase may vary depending on harvest year, wheat cultivars and growing location. This means that different commercial xylanases often will have to be evaluated in different doses, using labor extensive baking trials, to find the optimal solution. A too high dose might give sticky dough and a too low dose will not give the optimal functionality. The reason for this variation is explained in the literature by differences in xylanase specificity. This difference in specificity gives the xylanases different efficiency for the water un-extractable arabinoxylan and water extractable arabinoxylan. However, based on the hypothesis put forward in the literature, we are not able to explain the functionality we observe of different xylanases in a complex dough system. Using fractionation and reconstitution experiments, we have obtained new data indicating that the degree of inhibition of a xylanase by the endogenous xylanase inhibitor, may have a significant impact on the functionality of the xylanase in dough systems. The data presented, may help explaining the differences observed in functionality between xylanases, and make the selection of the optimal xylanase for a given application easier. These findings have also been used to design a new range of xylanase products, for which data will be presented.