## 3 Sorbates and Benzoates  
Potassium sorbate (PS), and sodium benzoate (SB) are used as preservatives in the food industry. Based on European nomenclature, PS is also known as E202, and SB as E211. They have antifungal and antimicrobial properties, inhibiting the growth of bacteria, yeast, and mold. Moreover, PS and SB are generally recognized as being safe (GRAS). PS is a potassium salt of sorbic acid, while SB is a benzoic acid salt, with both of them odorless and soluble in water [5,6]. Some applications of PS include cheese, fruit juice, margarine, bakery, canned tomato paste [5], and yogurt [49]. SB is used to conserve acidic pH foods such as fruit pulp and pureses, jams, beer, fruit yogurts, margarine, and salads [6,50]. According to the World Health Organization and the Food and Agriculture Organization of the United Nations, the recommended daily intake limit for PS is 25 mg/kg body weight [7]. In March 2019, the European Food Safety Authority [51] changed the temporary acceptable daily intake value to 11 mg sorbic acid/kg body weight per day for potassium salt, based on new data about reproductive toxicity. Regarding SB, the limit of daily is 5 mg/kg body weight [5]. For example, a person who weighs 70 kg can safely ingest 770 mg and 350 mg of PS and SB per day, respectively, without suffering negative effects [50]. [PERSON] et al. [4] reported values of \(178.75\pm 1.75\) and \(23.31\pm 4.11\) mg/kg of yogurt for potassium sorbate and sodium benzoate mean amounts in yogurts, respectively, namely, in fruit concentrate yogurts, and it is not difficult to exceed the acceptable daily intake recommended by the authorities. Therefore, it is important to look for alternatives to synthetic preservatives to reduce their use or even replace them entirely. In acidic foods such as yogurt, PS inhibits the growth of bacteria, fungi, and yeast [52]. However, using PS in corrupted and alkaline foods is not recommended [6]. The antimicrobial activity of PS and other preservatives, such as sorbic acid, is associated with the carboxyl group (-COOH) and the number of carbon atoms in its structure. Sodium acetate and potassium sorbate have higher antimicrobial properties compared to other additives. This fact relates to their shorter carbon chains and the ability to cross cell membranes [52]. \begin{table}
\begin{tabular}{c c c c c} \hline
**Type of Yogurt** & **Study Factor** & **Textural and Rheological Properties** & **Syneresis** & **Reference** \\ \hline Low-fat stirred & & Increased apparent viscosity. & - & [43] \\ \hline \multirow{4}{*}{Stirred} & Post-heating & Treatments below 65 \({}^{\circ}\)C/25 s increased gel & \multirow{4}{*}{-} & \multirow{4}{*}{[44]} \\  & Post-heating & strength, firmness, and viscosity. & & \\  & treatment & Treatments above 65 \({}^{\circ}\)C/25 s-Decreased & & \\  & & these properties. & & \\ \hline \multirow{2}{*}{-} & Concentrated & \multirow{2}{*}{Decreased viscosity.} & \multirow{2}{*}{-} & \multirow{2}{*}{[45]} \\  & strawberry pulp & & & \\ \hline Unstirred & Exopolysaccharides & Increase gel strength and viscosity. & Decreased & [46] \\ \hline \multirow{4}{*}{Stirred} & Heat exchanger type & Plate heat exchanger. & Decreased & \\  & & Tubular heat exchanger, firmer yogurt gel. & - & \\ \cline{2-5}  & Fat content & Increased firmness and viscosity. & Decreased & \\ \hline \multirow{4}{*}{Stirred} & \multirow{4}{*}{Smoothing temperature} & Yogurt at 42 \({}^{\circ}\)C: & \multirow{2}{*}{Increased} & \multirow{4}{*}{[48]} \\  & & heterogeneous microstructure. & & \\ \cline{1-1} \cline{4-5}  & & Yogurts at 20 \({}^{\circ}\)C and throughout a & & \\ \cline{1-1} \cline{4-5}  & & 42 \({}^{\circ}\)C-to-20 \({}^{\circ}\)C cooling ramp: & & \\ \cline{1-1} \cline{4-5}  & & homogeneous network. & & \\ \cline{1-1} \cline{4-5}  & & The apparent viscosity was higher at 20 \({}^{\circ}\)C & \multirow{2}{*}{-} & \\ \cline{1-1} \cline{4-5}  & & than at 42 \({}^{\circ}\)C. & & \\ \hline \end{tabular}
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