Rheological dough properties of organic spelt and emmer wheat for assessment of bread making quality

The aim of this study was to assess the quality of ancient wheat species and to examine the relations between rheological, indirect quality parameters and direct baking test. Winter spelt (Triticum spelta L.) and winter emmer (Triticum dicoccon Schrank) wheat significantly differ in grain, flour and rheological quality parameters and specific bread volume. It was found that protein quantity, Zeleny index and wet gluten quantity were significantly higher for spelt, but quality of gluten (gluten index) was higher for emmer. Mixolab parameters: speed of protein network weakening (slope alpha) and speed of starch gelatinization (slope beta) were slower for emmer; starch retrogradation (torque C5) was lower and time of starch gelatinization was longer for emmer. Principal component analysis (PCA) revealed that spelt and emmer wheat were strongly discriminated by the grain quality, farinograph rheological quality, Mixolab parameters and direct baking test. Based on PCA and Pearson's correlation coefficients, specific bread volume of emmer was highly associated with protein weakening (torque C2), farinograph dough stability, dough development time and wet gluten quantity. On the contrary, spelt specific bread volume was associated with Zeleny index and negatively correlated with Mixolab speed of the protein network weakening (slope alpha). These parameters are the most promising for the prediction of spelt and emmer bread making quality.