Compressed Yeast and Type I Gluten-Free Sourdough in Gluten-Free Breadmaking

The replacement of gluten in cereal-based goods still represents a significant technological challenge, and obtaining high-quality gluten-free (GF) breads brings about the search for ingredients and technologies able to improve the overall features of these products. Even if the use of sourdough has been extensively studied for the traditional baking, thanks to its positive effects on the product associated with the metabolic activities of sourdough-resident microorganisms; only in recent times, similar attempts have been made in GF baking. GF bread, in fact, is more generally produced by a straight-dough process, using compressed yeast as leavening agent. This research aimed to compare the properties of GF doughs and breads obtained using a Type I GF sourdough (GF-SD; in-lab developed), compressed yeast (Saccharomyces cerevisiae; CY), or their mixture (GF-SD + CY) during proofing. There are no studies, in fact, on Type I GF-SD with the stable association between the lactic acid bacterium Lactobacillus sanfranciscensis and the yeast Candida humilis. GF-SD doughs were comparable to CY doughs in terms of height development (adopting a longer fermentation step), and well-developed doughs were obtained in a short time when GF-SD was combined with CY. Despite the lower specific volume and the denser crumb, GF-SD breads were characterized by a more coherent texture, while CY breads were more prone to fracture during storage. Breads leavened with GF-SD + CY showed intermediate features. The promising results coming from the use of the in-lab developed GF-SD thus confirmed the positive effects of adopting the sourdough technology in GF breadmaking, too.