LARGE ENHANCEMENTS IN LOAF VOLUME AND ORGANOLEPTIC ACCEPTABILITY OF WHEAT BREAD BY SMALL ADDITIONS OF PUMPKIN POWDER - POSSIBLE ROLE OF ACETYLATED PECTIN IN STABILIZING GAS-CELL STRUCTURE

Pumpkin powder, introduced initially as a nutritional supplement, has been found to give very large, unexpected, increases in the loaf volum e and organoleptic acceptability of wheat bread produced using flour s amples with comparatively poor breadmaking properties. Maximum effecti veness occurs at low levels of addition, where the nutritional benefit would be marginal, but the improvement in quality is massive, suggest ing a possible role for pumpkin powder as a functional ingredient in b readmaking. Two hard wheat red Winter flours (denoted as samples F1 an d F2) were used. The gluten networks formed by these samples were foun d to be respectively weaker and stronger than the optimum range for br eadmaking, giving breads with relatively low specific volumes (similar to 3.8 ml/g for F1 and similar to 3.2 ml/g for F2) and with low hedon ic ratings from a sensory panel. Progressive addition of pumpkin powde r gave an initial rise and subsequent decrease in loaf volume. The max imum values attained were higher for F1 than for F2 (similar to 5.6 an d 4.2 ml/g, respectively), but in both cases occurred at levels of add ition between 5 and 10 g/kg flour. Panel scores for organoleptic accep tability increased systematically with increasing loaf volume, reachin g a value close to the maximum of the 5-point hedonic scale used at sp ecific volumes above similar to 4.3 ml/g. The increase in aeration is tentatively attributed to surface activity of the highly acetylated pe ctin present as a major component (similar to 30% of the total dry-mat ter content) of pumpkin tissue. (C) 1998 Elsevier Science Ltd. All rig hts reserved.