Re301

The pectin yield (PY) of RDF-PP was determined using the method described by Zahari et al. [24 (link)]. In an ISO glass bottle, RDF-PP was extracted with water in a 1:50 (w/v) ratio at pH 2.0 ± 0.03 using citric acid with continuous stirring at 150 rpm in a water bath (MaXturdy 18, Daihan Scientific, Gangwon-do, Korea) at 68 ± 0.4 °C for 77 min. After cooling, the suspension was filtered (Whatman N° 113) and concentrated to 50% of its initial volume in a rotary evaporator (RE301, Yamato Scientific, Tokyo, Japan) at 55 °C, 81 rpm, and 90 kPa. For the precipitation of pectin, 96% ethanol (v/v) was added to the concentrated solution at a 1:2 (v/v) ratio, and the mixture was kept at 4 °C overnight. Next, the uppermost pectin layer was subjected to filtration and underwent a series of three washes using ethanol solutions at 50, 75, and 100%. Then, the retained pectin was dried in an oven at 50 °C until constant weight, cooled, ground, and weighed. The PY was calculated using the following equation: $$\mathrm{P}\mathrm{Y}\left(\mathrm{\%}\right)=\frac{\mathrm{P}}{{\mathrm{W}}_{\mathrm{i}}}\times 100$$
where ‘P’ represents the weight of dried pectin (g) and ‘W_i’ represents the initial weight of the sample (g).

In this study, the fruits were harvested from a family vegetable garden in Obregon, Mexico, transferred to the Emergent Technologies Laboratory at the Technological Institute of Sonora. The fruits were washed and the edible part were separated and stored in a freezer (−20 °C) until analysis.
Extraction of phenolic compounds was performed according to the method proposed by Suárez, et al. [37 (link)] with some modifications. A representative portion of fruits (8 g) was homogenized in 40 mL of water, water:ethanol (20:80, v/v) or water:methanol (20:80, v/v) at 250 rpm using ultra-turrax T18 basic homogenizer (Ika Works Inc., Wilmington, NC, USA). The water and the mixture water:ethanol were selected as solvents because these fruits are consumed as fruit water but their peel or the whole fruit might be used to obtain ethanol-based tinctures for therapeutic purposes, as reported for other small fruits [38 ]. The mixture water: methanol (20:80, v/v) is highly used for the efficient liberation of phenols from vegetable foods [39 (link)]. The extracts were vacuum filtered through Whatman #1 paper, the solvent was evaporated in a rotary evaporator (RE301, Yamato, Santa Clara, CA, USA) at 30 °C, and the residue was stored at 4 °C until further analysis. Six extracts were obtained for each fruit type (red and yellow mombin).