Characterization of Pectins Extracted from Different Varieties of Pink/Red and White Grapefruits [ Citrus Paradisi (Macf.)] by Thermal Treatment and Thermosonication

LA CAVA, ENZO L.; GERBINO, ESTEBAN; SGROPPO, SONIA C.; GÓMEZ-ZAVAGLIA, ANDREA

JOURNAL OF FOOD SCIENCE

WILEY-BLACKWELL PUBLISHING, INC

Año: 2018

0022-1147

Thephysical and chemical properties of pectin extracts obtained from differentwhite and pink/red varieties of grapefruit [Citrus paradisi (Macf.)],using both conventional heating (CHE) and thermosonication (TS), wereinvestigated. The content of galacturonic acid (GalA), degree of esterification(%DM), color and antioxidant capacity were analyzed. Fourier‐Transform InfraredSpectroscopy (FTIR) associated with multivariate analysis enabled a structuralcomparison among the pectin extracts, and differential scanning calorimetry(DSC) completed a full landscape of the investigated extracts. Pectin extractsobtained by CHE showed mostly higher GalA than those obtained by TS. All theextracts had a high antioxidant capacity, as determined by 2,2 diphenyl1‐picrylhydrazyl (DPPH*) and2,2′‐Azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) diammonium salt (ABTS*+)assays, and a high correlation with the GalA content. The main differencesobserved in the FTIR spectra occurred in the 1200 to 900 cm−1 region(differences in GalA). The glass transition temperatures (Tgs) of all extractswere above 85 °C, making them interesting as stabilizing agents for the foodindustry.