## 3 Results and Discussion
### Optimization of the KCl and NaClFormulation  
An important objective of this research was to calculate the optimal values of the rheological parameters of the dough. For this purpose, the Derringer desirability function (Equation (2)), a multi-criterion decision-making method, was used [44; 45]. The optimization process using the numerical method by the Design-Expert was performed. \[D=\left(d_{1}^{r_{1}}d_{2}^{r_{2}}\ldots d_{n}^{r_{n}}\right)^{\frac{1}{2r_{i }}} \tag{2}\]  
where \(d_{1}d_{2}\),..., \(d_{n}\) are the desirability indices for each dependent variables and \(r_{1}r_{2}\),..., \(r_{i}\) are the relative importance of the dependent variables. A non-zero value of \(D\) from zero implies that all responses are in desirable range and, for a \(D\) value close to 1, the response values are close to the desirable values (Figure 4). By applying the desirable function methodology, the optimal values of the independent variables were obtained. The optimum values of the amount of KCl are 0.37 g/100 g wheat flour, and the optimal amount of NaCl is 1.31 g/100 g wheat flour. For these optimal solutions, the optimal values for the dependent variables were obtained: WA--56.626%, DT--1.805 min, ST--10.471 min, DS--43.454 UB, Tg--64.149 \({}^{\circ}\)C, PVmax--1281.438 BU, Tmax--89.513 OC, FN--383.978 s, H'm--59.714 mm, VT--1192.988 mL, VR--1098.555 mL, CR--92.027%, E--104.475 cm\({}^{2}\), R\({}_{50}\)--433.33 BU, Ext--138.923 mm, R\({}_{\max}\)--549.359 BU and R/E--3.95 with a desirable function score of 0.594. Figure 4: Desirability function scores for the independent variables and the studied dependent variables. Strategy Approach for Bakery Products' Reformulation for Sodium Amount Reduction Related to Our KCl-NaCl Optimum Values  
Bakery products are one of the main dietary sources of salt in most European countries. It seems that the highest consumption of bakery products occurred in the Eastern and Central Europe. In Northern Europe, other products, such as those of animal origin, are the main dietary sources of salt intake. Nowadays the daily salt intake in most EU countries ranges from 7 to 13 g per day (with the lowest intake values in Northern Europe countries and the highest ones in Central and Eastern countries), exceeding the World Health Organization's recommendation data [46]. Due to this, many European countries recommended food reformulation in order to reduce the salt content from its food, running many nutrition action plans for this purpose. For example, the Ministry of Health from some EU countries recommended reducing salt in bakery products by 15% up to 2015 in Austria, with 10% up to 2012 in Italy, with 20% up to 2014 in Spain, etc. [15]. The maximum target for the salt level that want to be achieved varies from one country to another. For example, of 2.35% for bread products from Hungary from 2019 and of 1.4% for bakery products from Spain. These high differences between EU countries' targets are related to the usual levels that normally exist in these countries' bread products. For example, the level of salt from popular Hungarian bakery products is around of 3% [47], whereas in Spain the mean salt content from the bakery products is around 2% [48]. Besides the fact that salt reduction in bakery products affect its technological process, a fact developed in quite a large extent during this study, it also affects bakery products' quality. According to our study, a 22% replacement of NaCl in a dough recipe through KCl is optimum in order to obtain bakery products of a very good quality. According to the data from the international literature, a 20% sodium reduction in bakery products did not affected bread quality from the sensory (including taste) point of view [46]. Regarding the use of KCl as a NaCl substitute, previous studies have shown that its addition up to 20-30% did not affected the taste of the bakery products. However, levels higher than 30% of KCl addition in wheat flour led to metallic and bitter aftertastes, a fact that is not recommended it in bread making [10].