Physicochemical variability and nutritional and functional characteristics of xoconostles (Opuntia spp.) accessions from Mexico

Introduction. The genus Opuntia generally produces fruits with abundant pulp and sweet taste, but also acidic fruits known as xoconostles, which may have a high potential for use and consumption. The aim of this study was to evaluate the physicochemical, nutritional and functional characteristics of 10 xoconostle genotypes produced in Mexico. Materials and methods. The xoconostle genotypes were collected from Hidalgo, Zacatecas and State of Mexico in Mexico. The pH, soluble solids, and titratable acidity, as well as the proximate composition and content of total phenolic compounds, betalains and antioxidant capacity (Trolox) were determined. Results were analyzed using analysis of variance (ANOVA) procedures and the Tukey test at a significance level of 0.05. Results and discussion. It was observed a high variability in weight (44.5-84.3 g FW), soluble solids (4.2-6.12 degrees Brix), titratable acidity (0.10-0.19 g 100 g(-1) FW), and pH (2.74-3.54) among the 10 genotypes of Opuntia spp. studied. The protein content varied from 0.60 to 0.87 g 100 g(-1) FW. Xoconostle genotypes with high calcium content of 1.008 mg 100 g(-1) FW were identified. Some xoconostle genotypes can be a good source of pigments due to their high content of betacyanins (0.76-5.06 mg 100 g(-1) FW) and vulgaxanthins (1.83-4.76 mg 100 g(-1) FW). The antioxidant capacity of some xoconostle genotypes was higher than that of other common fruits. Conclusion. The xoconostle genotypes evaluated have a potential to be exploited as a suitable source of pigments and antioxidant compounds.