Electron beam irradiation pretreatment for efficient extraction of pectin from spaghetti squash peel: Structural, functional, and biological properties

The effects of electron beam irradiation (EBI) pretreatment on the extraction, structure, functional, and biological properties of pectin from spaghetti squash peel were investigated. The spaghetti squash peel powder was pretreated by EBI with different doses (0, 25, 50, 75, 100, 125, and 150 kGy), and then pectin samples were successfully prepared in combination with acid extraction. At low doses (25 and 50 kGy), EBI had little effect on the basic structure of pectin, which was manifested by the high molecular weight, degree of esterification and viscosity of the extracted pectin. Additionally, pectin obtained at middle doses (75 and 100 kGy) exhibited high homogalacturonan (HG) domain and excellent thermal stability, while pectin extracted at high doses (125 and 150 kGy) manifested high rhamnogalacturonan I (RG-I) content, low molecular weight, and superior antioxidant and probiotic properties in vitro. Reasonable modulation of irradiation doses could obtain the desired pectins with different structures and properties. These findings provides valuable insights regarding the role of EBI pretreatment in the extraction and quality improvement of pectin and further promotes the appropriate application of EBI in the food industry.