Abstract

A co-culture of Torulaspora delbrueckii JK08 and Pichia anomala JK04 in combination with commercial bakerʼs yeast (Saccharomyces cerevisiae) was used as a leavening agent in the preparation of Jerusalem artichoke powder (JAP)-enriched bread. The breads were made by substituting of 5, 7.5, and 10% wheat flour with JAP. Water absorption decreased with increasing JAP. JAP enrichment of 5% resulted adverse effect on dough development time, mixing tolerance index, and dough stability, but comparable to those in control bread at a higher dose. The use of a co-culture and JAP enrichment simultaneously decreased specific volume, but improved bread yield. The co-culture was able to slow the darkening effect of bread crumb imparted by JAP enrichment at a dose of 5 and 7.5%. Hardness and chewiness were worsened by the use of a co-culture and JAP enrichment, while springiness and cohesiveness were improved. The cell density and mean cell size of bread crumb were improved by the use of a co-culture, while cell area fraction was unaltered except at 10% of JAP-enrichment. In general, the use of a co-culture improved the consumer preference of JAP-enriched bread at a dose of 5 and 7.5%. Thus, we suggest the use of co-culture in bread making enriched with JAP for improved bread quality.

Key words: bread making, jerusalem artichoke, mixed culture, Pichia anomala, Torulaspora delbrueckii