Extraction, characterization and gelling ability of pectins from Araçá (Psidium cattleianum Sabine) fruits

Pectins from Araçá (Psidium cattleianum Sabine) fruit pulp were extracted, purified and isolated, obtaining the Purified Pectin (APP) under its sodium form. Yield was found 3.5% w/w of initial dried material. From titration, monosaccharide analysis after total hydrolysis 1H HSQC NMR analyses, it established that pectins are formed long galacturonic acid blocks (HG) partially methylated (degree methyl-esterification – DM = 55.9 mol%) acetylated (2 RG-I with side chains containing mainly arabinose galactose. No gelation observed in presence calcium for unmodified APP. Then, treated alkaline conditions to de-esterify progressively sample down 0 60 min treatment. Each obtained characterized by SEC demonstrating stability main chains, where Rha, GalA Mw remained unchanged independently length One this (APP-15) selected test gelling ability rheological behavior. The gel dialysis against 1 mol L−1 CaCl2 study allows conclude a homogeneous physical is stabilized cooperative GalA−-Ca+2 junctions.