# Strategies for Reducing Sodium Intake in Bakery Products, a Review
## 3 The Technological Effect of Sodium Chloride in Bread Making
Salt prevents water migration from crumb to crust and keeps the product fresh for a longer period of time compared to bread without salt addition [46]. The main responsible for foodstuffs' deterioration with high humidity content are microorganisms. Bread is known as a product with high humidity, with a\({}_{\mathrm{w}}\) values between 0.96-0.98 [47]. In general, the addition of salt increases the gelatinization temperature of starch and delays its gelatinization process [39]. Through its action on starch and gluten, but also on the activity of water from the dough system, salt has a major contribution on starch staling [48]. For example, reducing NaCl from 1.2% to 0.3% decreases the shelf life of the bakery products with almost two days [24]. Figure 3: The role of sodium chloride on bakery products quality. On the bread color, the reduction of the sodium chloride content in bread recipe or its lack thereof leads to products with a light-colored crust [31]. The brown color of the crust resulting from the bread baking process is due to the Maillard reaction, as an interaction between reducing sugars and amino acids. Therefore, a certain amount of free reducing sugars and amino acids is necessary for this reaction to take place. The lack of salt addition leads to a more intense fermentation which induces a high consumption of carbohydrates during the initial stages of the bread making process. Therefore, during baking the dough which presents less reduced sugars to form more melanoidins, will yield a bread sample with a light color. Many factors such as pH, protein/amino acid ratio, water, sugar amount from the dough system, temperature and baking time have a major influence on crust formation. The intake of sodium chloride produces a plasticizing effect during the baking process of bakery products, this favoring the Maillard reaction and therefore producing a darker crust [49]. Salt has the ability to control the yeast fermentation from the dough system and therefore, reducing the amount of salt will increase the activity of yeast. Fermentable carbohydrates are needed to the yeast fermentation process [50] and therefore, yeast fermentation will reduce the availability of free sugars involved in the Maillard reaction [24]. Sodium chloride is also responsible for the flavor of bakery products, which also intensifies the sweet taste of the finished product. Sodium salts such as sodium chloride or monosodium glutamate influences the food flavor in a positive way, improving it. However, [PERSON] et al. [51] concluded that consumers did not observe a gradual reduction of 5% sodium per week over six weeks (corresponding to a final reduction of 25% salt). A 20% reduction of sodium in bread did not affect the taste perception of 60 participants in this study. Instead, [PERSON] et al. [35] showed that a 50% reduction in salt changed the bread flavor. Salt-free bread has been described by them as sour and having the taste of yeast [12]. Research has shown that sodium, and to a lesser extent lithium, are the only salted cations with good effects on sensory food properties while calcium and potassium ions have a bitter or metallic taste, which is undesirable for consumers [52]. This effect of sodium chloride on sensory perceptions are due to the fact that free Na\({}^{+}\) ions in solution are the mainly responsible for the perception of salty taste on the tongue while the contribution of Cl\({}^{-}\) ion in terms of taste is not yet fully clarified. Due to the interaction between sodium chloride and wheat proteins during dough formation, sodium ions interconnect with dough components due to their ionic interactions with negatively charged amino acids [1]. [PERSON] et al. [53] reported that Na\({}^{+}\) and Cl\({}^{-}\) ions are not irreversibly bounded in bread, sodium ions being released by chewing. The speed with which sodium is released in the first seconds when chewing takes place is quite important for the perception of salty taste by the consumers.