Characterization of water soluble pentosans of enzyme supplemented dough and breads

Water soluble pentosans (WSP) from doughs and breads made with different en zyme preparations are characterized according to extraction yield, sugar co mposition, xylose/arabinose ratio and molecular weight (MW) distribution. E xtraction yield was greater for dough than for bread samples, ranging from 0.94 to 1.64%, but bread extracts had a higher purity. Percent of pentoses in purified WSP was greater in pentosanase supplemented samples (28-55%) th an in control and amylase containing samples (23-32%). Major sugars were xy lose and arabinose, but glucose and mannose also appeared in the extracts. The xylose/arabinose (Xyl/Ara) ratio was 1.3-1.6 and underwent small change s during processing. Enzyme addition caused an increase in Xyl/Ara ratio, a ttributable to a debranching of arabinoxylans (AX) with higher degree of Ar a substitution by arabinofuranosidase. Addition of pentosanases had a signi ficant effect in increasing WSP with MW over 39 000, whereas those of low M W changed only slightly MW distribution depended on enzyme source, and wher eas some enzymes showed activity during fermentation others increased their activity during baking. No synergistic effects were observed in studied va riables due to the combination of amylases with pentosanases. Protein in WS P extracts eluted together with ferulic acid suggesting they were linked, b ut not associated with a determined carbohydrate fraction.