**3.3 Determination of titratable acidity**

It was determined based on the norm NOM-155-SCFI-2012 [24], taking 10 mL of sample, 20 mL of distilled water, and two drops of phenolphthalein, carrying out the titration with 0.1 N NaOH. The calculation of titratable acidity was carried out using the following equation: ⁄L) = \_

$$\mathbf{Acidity(\%)\_L} = \frac{(\text{V)(N)} (90)}{\text{M}} \tag{1}$$

where V = milliliters of 0.1 N NaOH solution, spent in the titration; N = normality of the NaOH solution; M = volume of the sample in mL; 90 = lactic acid equivalent.
