REVIEW - FACTORS INFLUENCING THE QUALITY OF WHEAT SOURDOUGH PROCESSES, AND THE USE OF CHEMOMETRICS IN QUALITY ASSESSMENT

Sour doughs are essential in controlling the quality of rye and rye-wh eat breads. In wheat bread production, sour doughs enhance bread flavo ur, crumb grain and structure, and extend bread shelf-life. Sourdough processes are governed by numerous external and internal factors. Flou r extraction rate and differences in flour quality are of primary impo rtance when wheat flours are considered. Interactions between internal and external conditions affect in a complex way biochemical character istics of sour doughs. In addition to flour, other process conditions such as sourdough process (single, multistage), starter (seed dough, s pontaneous dough or microbial starter) and dose of addition determine the quality of resulting doughs and breads. Many fermentative, biochem ical, and rheological properties of doughs, as well as physicochemical , sensory characteristics and shelf life of breads, maybe affected. Qu ality sour dough criteria have been established for rye breads, but th ey cannot be extrapolated to wheat breads. Actual trends are concerned with two, in some way, opposite directions: improving bread flavor ma intaining low levels of sour dough, and extending shelf life by enhanc ing acetic acid contents of breads. Data generated may difficult the a nalysis of results, explaining differences in performance and drawing conclusions. Chemometrics, including qualitative and quantitative mult ivariate statistical techniques have proved to be useful in studying w heat sourdough processes for assigning quality indexes on the basis of objective measures, correlations among process conditions, analytical variables and consumer preferences, and indicating the variables nece ssary for quality assessment.