Evaluation of Chemical and Functional Properties of Pectin-like Polymers Extracted from Tomato Using Conventional Acid Extraction

Abstract

The present study focuses on the extraction, characterisation, and functional properties of pectin-like polymers from tomatoes. The results revealed that the highest pectin yield (35.5%) of the dry weight was extracted at pH 1, whilst the lowest yield (25.4%) was extracted at pH 3. Fourier Transform Infrared (FTIR) spectra displayed major peaks at 2900–3300 cm−1 and 900–1100 cm−1, which are typical of carbohydrate polymers. A compositional analysis revealed the presence of six monosaccharides (glucose, arabinose, fucose, galactose, mannose, and galacturonic acid) together with trace amounts of xylose, which are typical of pectin (or pectin-like) structures. This suggests that the pectin-like polymers have galactan and/or arabinan side chains. The emulsifying activities and stabilities were ≥50% and ≥96%, respectively. The pectin-like polymers also demonstrated notable antioxidant activities (70%) when determined using the 1-diphenyl-2-picrylhydrazyl (DPPH) assay.