Effect of sourdough starter and fungal proteases on gluten content and sensory properties of tarhana

In this study, gluten degradation during prolonged tarhana fermentation was monitored in a traditional dough as well as in dough containing sourdough starter, peptidase additives and combination of both. Gluten content, determined using the sandwich ELISA assay method, was reduced significantly in the first 5 days of fermentation for all formulations. After 30 days into fermentation, approximately 15% and 20% reduction of gluten was observed in the traditional dough and sourdough starter added dough, respectively. In enzyme supplemented formulations, the mean gluten levels were below 20 ppm by 20 days of fermentation. Results showed that proteolytic enzyme addition to the dough mix can potentially render long fermented tarhana a food which conforms to regulations set forth for gluten-free foods, even though wheat flour is one of the main production ingredients. Sensory evaluation of the 30 day fermented tarhana samples revealed differences in sourness and odour properties of the products.