## 1 Introduction  
Bread is one of the most widely consumed foods in the world and it is at the base of the Mediterranean diet pyramid. Today, several baked foods are produced by sourdough, a fermented dough that is used worldwide. Sourdough fermentation involves lactic acid bacteria in mixture with yeasts that are responsible for influencing the features of leavened baked goods and may have positive effects on human health [1]. For example, breads obtained by sourdough fermentation show a reduction in the concentration of fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) whose intake is associated with the onset of irritable bowel syndrome symptoms. FODMAPs present differences in carbohydrate digestibility and absorption and a lower post-prandi glycaemia response [2]. Moreover, a better digestibility of sourdough compared to baker's yeast breads was recently observed [3], as well as the ability to decrease the release of pro-inflammatory cytokines induced by amylase/trypsin inhibitors and that are degraded during the fermentation [4]. All this set of healthy effects can be due to the type of grain flours, on the one hand, and to the mixture of lactobacilli (LAB) and yeasts used for fermentation, on the other [5]. The metabolism of sourdough microbiota, the activity of cereal enzymes, and the peculiar composition of the grains work together to determine the presence of low-molecular-weight compounds, phenols, and peptides responsible for improving the nutritional value of the baked product [6; 7]. The formation of a stable microbiota is difficult to standardize, and the use of microbial starters able to guarantee fast, efficient, controllable, and reproducible fermentations may be the method of choice for obtaining baked goods equipped with technological, sensory, and nutritional properties [5]. LAB selection consists in the study of a large number of strains that are characterized for various activities, growth and acidification rate, and capability to increase or to produce bioactive compounds, such as peptides and amino acid derivatives [5; 8]. The screening of numerous isolates of LAB from Italian sourdoughs obtained with commercial wheat flour (type \"00\") led to the identification of three strains belonging to _Companilactobacillus farciminis_ (formerly known as _Lactobacillus farciminis_, [9]). _Furfurilatobacillus rossiae_ (formerly known as _Lactobacillus rossiae_), and _Fruticilactobacillus sanfranicsensis_ (formerly known as _Lactobacillus sanfranicsensis_), which were selected for their ability to produce bioactive peptides endowed with antioxidant and anti-inflammatory activity [8]. Bioactive peptides also retained their functional properties in the breads prepared with the same sourdoughs [10]. Depending on the starting material sourdoughs or breads, the peptides have different amino acid compositions, which in any case does not imply changes in their biological activity [10]. On the other hand, the final features of sourdoughs and breads are closely connected to the type of grain used during the baking process. Whole grain and particularly pigmented cereals are an important source of bioactive compounds, micronutrients, and dietary fiber [11; 12; 13]. In particular, some pigmented whole grains are innovative and valuable raw materials for the production of functional foods. Together with phenolic acids, these grains show significant levels of anthocyanins and carotenoids, bioactive compounds responsible for their characteristic blue-purple and yellow-orange colors, and for their nutritional value [14; 15]. The nutritional quality of breads can also be related to the content of beta-glucans, of which hull-less barley is rich in; consequently, it has been recently proposed for the manufacture of functional foods [16]. Therefore, determining the most suitable combination of selected LAB and high-functional-value flour can be the way to produce healthy baked goods.