Effects of the addition of a meal deriving from toasted durum wheat kernels on dough properties and spaghetti cooking behavior

The aim was to study the effects of toasting of durum wheat kernels on the properties of dough and spaghetti produced with semolina and increasing amounts of the meal deriving from toasted kernels. The replacement of semolina with the toasted meal caused a decrease in the dough strength and an increase of its tenacity already at a substitution level of 100 g kg(-1). Pasta made with 100% semolina or with a mixture of semolina and 200 g kg(-1) of toasted durum wheat meal appeared as the best, being the less compressible and showing the highest values of cohesiveness. Water sorption curves were successfully described through the Peleg's equation. The application of response surface regression followed by stepwise regression allowed to write one equation for each of the textural properties measured. Gluten index was the best predictor of compressibility, cohesiveness, and gumminess whereas elasticity was better predicted on the basis of both gluten content and gluten index. Observed and predicted values were highly correlated with R-2 ranging from 0.707 (compressibility) to 0.867 (gumminess).