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