Use of artichoke by-products and sourdough biotechnology to design a functional gluten free bread

During industrial processing, many parts of the artichoke plant (Cynara cardunculus L.) are discarded despite these by-products are still characterized by a conspicuous presence of dietary fibers, phenolic acids, and other healthy micronutrients. The present work aims to characterize a laboratory-made gluten free (GF) bread enriched in artichoke extracts (AE). A mixture of rice and corn flours (ratio 1:1) constituted the control GF-bread (dough yield, DY 180). The AE, characterized by 0.05% titratable chlorogenic acid, was added (8% of dough weight) in experimental GF-breads (GF-AE). Both GF and GF-AE breads were made with baker’s yeast or with GF sourdough. Compared to GF breads, GF-AE samples showed a higher level of soluble fibers and antioxidant compounds. The GF-AE bread made with sourdough showed the lowest glycemic index. After simulated gastrointestinal digestion of breads, digests were tested in fecal batches containing viable cells of fecal microbiota delivered from healthy donors. The use of sourdough in GF-AE bread increased the cell density of health promoting bacteria in batches. Furthermore, the soluble fraction from each digested sample was tested on rat hepatoma FaO cells and human wild-type Hep G2 cell line. As assessed by lipid peroxidation assay, the use of AE in GF-breads combined with sourdough biotechnology reduced cellular oxidative stress. The panel test did not assess significant differences in bread acceptability. Therefore, the results of this study suggested that artichoke by-products combined with sourdough biotechnology could be a promising tool to increase nutritional and healthy features of GF-breads.