# Influence of Technological Parameters on Sourdough Starter Obtained from Different Flows
## 4 Discussion  
The baking process is a complex process based on a large number of physical, chemical, colloidal, biochemical, and microbiological processes. Some of these cannot occur without others, some follow each other, and often, they condition each other so that they cannot be treated individually. Figure 2: Evolution of lactic acid bacteria and yeast populations compared to pH values in the case of doughs fermented at 25 \({}^{\circ}\)C (Results are presented as mean of two determinations \(\pm\) SD). The complexity of the baking process is largely due to the development and fermentation of the dough, which is a viscoelastic semi-finished product with a certain consistency imposed by the technological process and which can hardly be acted upon from the outside. Consumer interest in the last 20 years has led to the re-invention of the technological process by increasing the production of sourdough, a fermented semi-finished product, and also the production of selected microbial strains for the preparation of sourdough [14]. The use of the sourdough-based technological process as the basis of fermentation and leavening is one of the oldest biotechnological processes in the production of cereal foods [15]. Each sourdough is a different natural ecosystem that can produce a different quality of bread, the microbial metabolism being specific to the strain, the intermediate metabolites formed, especially flavor compounds but also antibacterial compounds, conferring a sensory and hygienic quality to bakery products based on yeast in comparison to conventional bread. Type I sourdough can be maintained for years by continuous refreshment using the previous batch as inoculum. The type of flour that is used during starter maintenance can affect the culture's ecology, technical efficiency as a leavening agent, and unique sensory qualities. flour helps introduce microorganisms into the dough environment [16]. Also, flour provides different nutrients (carbohydrates and amino acids) and non-nutrients (phenolic acids, amylase, ash), whose presence and concentrations can influence the survival of bacteria and yeast species [17; 18; 19; 20]. Phenolic compounds and ash are naturally present in flour in varying amounts and have been shown to affect the acidification rate of starter cultures, thereby influencing microbial succession. Similarly, the presence or absence of the bran portion of cereals may also influence microbial ecology in ways that are not yet clear [21]. The study followed the chemical and microbiological characteristics of different variants of spontaneous sourdoughs obtained by combinations of wheat flour, corn flour, and rye flour, fermented at different temperatures, 25 \({}^{\circ}\)C and 35 \({}^{\circ}\)C, over a similar period of time (96 h). Thus, seven variants of spontaneous fermentation sourdoughs were tested. The flours used to obtain them were purchased from local producers and were from organically certified crops. Sourdough production is relatively simple and does not need complicated installations and can obtain different products with different characteristics just by varying the ratio between raw materials. By changing the rations and recipe, different sourdough can be obtained to promote diversity and different microbial ecosystems. At the beginning of fermentation, the dough fermented at 25 \({}^{\circ}\)C had higher pH values than those observed in the batches of dough fermented at 35 \({}^{\circ}\)C and a slower increase in acidity. In parallel, the number of LAB was much higher in the dough fermented at 35 \({}^{\circ}\)C at the beginning of fermentation, but after 24 h, the batches of dough fermented at 25 \({}^{\circ}\)C had a higher number, which remained more or less constant until the end of fermentation. In the case of sourdough samples fermented at 25 \({}^{\circ}\)C, the pH values started from an average of 6.31 and decreased to an average of 3.82, and in the case of sourdough fermented at 35 \({}^{\circ}\)C, the pH value varied from an average of 5.37 to 3.46.