Relationships between biochemical and quality-related characteristics of breads, resulting from the interaction of flour, microbial starter and the type of process

The possible relationships between biochemical characteristics [total starch, sugars, low-molecular-weight dextrins (LMWD), acetic and lactic acids, soluble solids and crumb-swelling power] and characteristics related to the quality of wheat bread (volume, texture and sensory quality scores) have been investigated. Variables influencing the possible interactions occurring were the type of flour (white and whole-wheat flours), the starter microorganism (Lactobacillus brevis, L. plantarum) and the type of process used to introduce the lactobacilli inoculum (sourdough, straight). The main factor explaining variability of data was related to sensory quality attributes and physical characteristics of the breads. The second factor was related to LMWD and the third to the acidity and lactic acid content of breads. The first factor permitted separation of the bread samples into two groups on the basis of flour extraction sate, whereas LMWD allowed differentiation between white breads made with sourdough or straight processes. Cluster analysis included the level of acidity and the lactic acid content as additional factors grouping control breads (without starter) together with breads made using a straight process. The best canonical correlation was established between the physical characteristics of breads and carbohydrates, soluble solids and crumb-swelling power. The first pair of canonical variables between two sets of experimental variables showed a squared correlation coefficient of 0.986.