Preparation and characterization of pectin fraction from pineapple peel as a natural plasticizer and material for biopolymer film

Abstract

Microwave heating extraction (ME) of pectin from pineapple peel were investigated. The yield was 1.02–2.12% with good quality of pectin. Increasing irradiation time (30–60min) increased yield but decreased qualities. The whole pineapple peel pectin extract solution (PPS) was used as a solvent and plasticizer in film formation. Increasing PPS to water ratio (0:100–40:60) enhanced film opacity (0.56–1.60), decreased water vapor permeability (2.96–2.11×10−10gm−1s−1Pa−1), and increased total phenolic content (TPC, 24.23–62.83mg gallic acid equivalents (GAE)/g film in water and 0–16.21mg GAE/g film in 95% ethanol). Nevertheless, TPC migrated quickly to the aqueous food simulant resulting in better antioxidant activity than in the fatty food simulant. Thus, pineapple peel showed good potential as a natural plasticizer with a source of pectin and phenolic compounds to produce edible films for various food applications.