Storage stability of laccase induced arabinoxylan gels

The effect of storage on laccase-induced gels of wheat water-extractable arabinoxylan (WEAX) was followed for 6 days at 25 °C. Gel hardness was greatly affected by aging (43% decrease in 6 days). This weakening appeared to proceed through a mechanism involving laccase-produced radicals. Once produced, they participated in secondary reactions leading to a slight degradation of WEAX main chains (20% decrease of MW and ηred values) and a decrease by 70 and 80% of their di and tri-ferulic acid content, respectively. The thermal inactivation of laccase after gel formation blocked the free radical production thereby stabilizing the gel. The changes in hardness (5% lost), MW (5% lost) and ηred (1% lost) were reduced in this case and the contents of di and trimers of ferulic acid were not modified.