Effects of increasing levels of transglutaminase on cooking quality of bran supplemented spaghetti

This study investigated the possibility of incorporating high levels of bran into spaghetti formulation by using transglutaminase (TG)-catalyzed crosslinking, without deterioration in spaghetti quality. Two durum wheat samples and one bread wheat sample were milled to semolina or farina. Ground mixture of coarse and fine brans of each cultivar was substituted for a portion of semolina or farina obtained from the respective cultivar, at the levels of 15 and 30% and then processed into spaghetti. Bacterial TG was added to the spaghetti formula at the levels of 0.2% and 0.4% (w/w). The results indicated that the TOM values and the sensory characteristics of the spaghetti were generally affected by the cultivar, bran supplementation, and TG addition level. The samples with TG exhibited significantly lower scores for TOM and higher sensory scores for firmness, stickiness, and bulkiness when compared with the respective control sample of each cultivar. As a result, transglutaminase addition had a significant improving effect on spaghetti quality which was more obvious in the weaker cultivar and it was possible to overcome the deteriorative effects of bran on spaghetti quality.