Enhancive effect of instant controlled pressure drop (DIC) pre-treatment on pectin extractability from peach pomace

Abstract

This study aimed to investigate if instant controlled pressure drop (DIC) processing can enhance pectin extractability from plant material. Peach pomace was treated by 0-, 1-, or 3-cycle of DIC processing at 90 or 105 °C. Pectin fractions including water soluble pectin and insoluble pectin were isolated from dried peach pomace and characterized by degree of methoxylation, neutral sugar composition, and molecular weight distribution. The results demonstrated that the thermomechanical effect of DIC processing induced a strong solubilization of in situ pectic polysaccharides of peach pomace, especially for water insoluble pectin fractions. This solubilization effect resulted in a more than 10% increasing ratio of extractable pectin yield from peach pomace over the maximum yield without the thermomechanical effect of DIC processing. Meanwhile, DIC processing conducted at 90 °C with 1-cycle affected pectin structure and property insignificantly. • DIC process induced solubilization of in situ pectic polysaccharides of peach pomace. • DIC treatment increased the pectin extractive yield of peach pomace by more than 10%. • 1-cycle DIC treatment at 90 °C affected slightly on pectin structure and properties.