Physicochemical and comparative properties of pectins extracted from Akebia trifoliata var. australis peel

The physicochemical properties of the pectins extracted from Akebia trifoliata var. australis peel with hydrochloric acid and citric acid, namely HEP and CEP, were evaluated as compared with citrus pectin (CP). X-ray diffraction confirmed that CP had more well defined crystal than HEP and CEP. The DE values of HEP, CEP and CP were 59.46%, 76.64% and 71.03%, respectively. CP exhibited the highest viscosity-average molecular weight of 64,848 Da, followed by HEP (45,353 Da) and CEP (28,877 Da). In general, the emulsion activity of HEP and CEP increased as oil concentration was increased, while HEP showed the strongest emulsion activity among the three pectins. Textural analysis demonstrated that the gelling properties of three pectins decreased with increase in pH, and CP displayed superiority in hardness (9.03 g), while CEP was the poorest (1.45 g). All results suggested that A. trifoliata var. australis had the potential in producing pectin for commercial food industry application.