Extraction and characterization of pectic substances in Myrciaria cauliflora (Jaboticaba sabará) fruit

Resumo

The jaboticaba is a fruit that is native to Brazil, which has antioxidant activity and is known to have levels of bioactive compounds. This fruit is a berry with a lilac-coloured husk and white flesh; sweet and acid, which justifies its high levels of fresh consumption. The aim of this study was to contribute to the study of a new raw material in small agribusinesses. Jaboticaba- Sabará variety- was fractionated into three parts for pectin analysis: the skin, pulp and juice. The pectic substances of the jaboticaba were analysed. The degree of methoxylation was determined by titration and infrared spectroscopy (FTIR). Pectin extracted from the skin had a higher degree of esterification. The macromolecular composition, determined by high pressure steric exclusion chromatography (HPSEC), discriminated the pectins of high molar mass (skin) and low molecular weight (juice and pulp). The pectin from all the fractions presented homogalacturonan segments with a high degree of esterification, and ramnogalacturan side chains composed of galactose and arabinose. The jaboticaba pectins presented a high content of arabinose in the skin, whilst galactose was only found in traces in the juice, showing different proportions of monosaccharides, similar to commercial samples of apple pectin.