Efecto del grado de madurez sobre las propiedades fisicoquímicas de pectinas extraídas de cascos de guayaba (Psidium guajava L.)

Abstract

The aim of this study was to evaluate the effect of maturity on pectin content of guava shells (Psidium guajava L.) growing red supreme Cuban. This was a completely randomized design of three levels (growth stages of maturity) and four replicates. The dependent variables are the physical and chemical parameters (pH, ash content, percentage of degree of esterification, methoxyl content, content galacturonic acid anhydrous equivalent mass and gel strength). Analyses were performed by triplicate except that gel strength was performed in quintuplicate. The data were analyzed by ANOVA, where significant differences applied a leastsignificant difference test (MDS) at 5%, using the statistical package SAS 2004. The pectin extracted presented a performance of 5.49% for green guavas, 5.24% for pintonas, and 4.77% for mature. The characteristics of the pectin extracted guavas hulls differed in all analyzed quantitative parameters except the ash content. The physicochemical characteristics of pectins state guava green and mature pintón were: pH 4.16, 4.11 and 4.01, ash content 1.40%, 1.69% and 1.80%, degree of esterification 88.58%, 80.53% and 64.60% methoxyl content of 2.53%, 1.64% and 0.83%, galacturonic acid content of 16.15%, 11.58% and 7.27% 9807.16 equivalent mass meq/mg, 7920.07 meq/mg and 6914.76 meq/mg and gel strength of 0.414 N, 0.149 N and 0.050 N, respectively. All parameters were a progressive decline in their values due to the physiological process of the fruit.