Mitigation of Apricot Quality Loss and Waste during High-Temperature Processing via Sonication and Pulsed Electric Field Pretreatments

Abstract

This study aimed to minimize thermal losses, particularly in apricot firmness, quality retention, and fresh weight (FW) reduction, by utilizing non-thermal pretreatments involving sonication, pulsed electric field (PEF), and calcium chloride (CaCl₂) soaking to mitigate softening caused during high-temperature blanching (85°C for 3 minutes). Enzymes such as polygalacturonase (PG), pectin methylesterase (PME), and cellulase, which degrade the cell wall during blanching, were mitigated through these pretreatments. Apricot cell walls, composed mainly of cellulose, hemicellulose, and pectin, were stabilized by soaking in a 2% CaCl₂ solution for 10 minutes before exposure to sonication and PEF. Sonication at 150W, 200W, and 300W generated cavitation, disrupting the cell wall and enhancing its susceptibility to PEF treatment. PEF treatments were applied with intensities of 1.5, 2.5, and 3 kV/cm for 30, 60, and 90 minutes. The optimal results were obtained with 200W sonication for 3 minutes and 1.5 kV/cm PEF for 30 minutes, preserving apricot firmness by 45% and reducing FW loss to 9%, compared to 20% in the control group. Structural analyses using FTIR, XRD, and SEM confirmed that these treatments reinforced cell wall integrity and minimized softening. Additionally, bioactive compounds, including polyphenols and flavonoids, were better retained, enhancing the nutritional value of the apricot. Sensory evaluations showed improved color, texture, aroma, and overall appeal in treated apricot samples. The results demonstrate that combining sonication, PEF, and CaCl₂ soaking provides a sustainable, effective solution to enhance firmness, reduce food waste, and improve apricot quality during thermal processing. This study offers valuable insights into optimizing apricot processing, with potential applications to reduce food waste, enhance texture, and retain bioactive compounds.