SENSORY PROFILING OF CHANGES IN WHEAT AND WHOLE WHEAT BREAD DURING A PROLONGED PERIOD OF STORAGE

ABSTRACT A sensory profile of wheat and whole wheat pan bread with extented shelf life was conducted to characterize sensory changes during a 3‐week storage period. Variation between assessors was also assessed together with repeatability of the profile. The robustness in the sensory profile was determined by comparing two sensory trials 4 months apart (with six assessors participating in both trials). Initially, assessors agreed on a consensus list of 14 attributes (wheat) and 17 attributes (whole wheat). Multivariate data analysis was used to study the effect of storage time and assessors on the sensory profile. The impact of storage time was especially evident for whole wheat bread, but results showed that storage time had a significant effect on aroma and flavor of both bread types. An agreement in the sensory evaluations over time was found, which emphasize the robustness of the profile, the consistency of samples baked at different times and the reliability of the obtained results. PRACTICAL APPLICATIONS The use of enzymes in bread production has made it possible to extend the shelf life of bread considerably by decreasing the rate of starch retrogradation. Thus, other parameters are decisive for shelf life determination – off flavor is believed to be one parameter of high importance. Off flavor development in bread is however an overlooked area in food research. Sensory profiling focusing on changes in sensory perception related to storage time will reveal the most important sensory alterations. These sensory alterations are highly relevant for consumer preferences and can furthermore be used as a tool to elucidate chemical mechanisms responsible for off flavor formation. Consequently, the present sensory profiling is of significant value for industrial bread producers, enzyme manufactures and finally the consumers. The knowledge can be included in future examinations of sensory and chemical changes of bread with extended shelf life aiming at enhancing the quality of such products.