*3.13. pH and Acidity Analysis*

pH of the functional beverage samples was measured by a calibrated PH meter (Adwa, AD1030). The acidity was determined according to Kazimierczak et al. and Yoon et al. [23,35] by titrating the juices with 0.2N NaOH till the pH reached 8.2. The total acidity was expressed as % of lactic acid by using the following Equation (5):

$$\% \text{Acidity} = (\text{V} \times \text{N} \times 0.09/\text{W} \times 100) \tag{5}$$

where: (V) is mL of NaOH, (N) normality of NaOH, and (W) weight of the sample.

#### *3.14. A Proximate Chemical Analysis of Fermented Beverage*

Moisture and ash content of LA-5 and ABT-5 fermented beet-milk beverages and beet-milk control were determined according to AOAC [38]. Total fat of beverages was estimated by Folch method [39], protein was determined by the micro-Kjeldahl method according to Peach and Tracy [40]. While the total carbohydrates were estimated by Phenol-Sulfuric acid method [49]. Mineral content was determined as described previously at **Section 3.4**.
