Detailed Explanation of Key Operational Points for Peach Quick-Freezing Processing Technology

(1) Process flow: raw material selection → pitting and color protection → blanching and cooling → peeling → packaging and syrup injection → pre-cooling → quick-freezing → frozen storage.

(2) Key operational points: Raw material selection. After peaches are harvested, ripe ones must be processed immediately; hard, unripe fruits need to be ripened. Properly ripened peaches have bright color, rich flavor, and are easy to pit and peel. Pitting and color protection: after the raw materials ripen, remove the pits with a small knife or a pitting machine, and immediately place the flesh into cold water to avoid contact with air and prevent discoloration. The pitting machine has flesh fragments attached, which often discolor and should be removed at any time. Blanching, cooling, and peeling: scoop out the pitted flesh, blanch it in boiling water for 2-5 min or steam-blanch it for 7-8 min. After blanching, immediately place it in cold water to cool, and peel off the outer skin. Packaging and syrup injection: after thorough cooling, drain the water from the flesh, package it in polyethylene bags or nylon/polyethylene composite bags. The proportions of flesh and syrup are 70% and 30% respectively, the syrup concentration is 50%, and 0.3% citric acid, 0.1% iso-Vc, and 0.2% calcium chloride are added. Pre-cooling, quick-freezing, and frozen storage: after sealing, pre-cool to about 0 degrees C, then carry out quick freezing. After freezing, use cardboard boxes for outer packaging, and finally store frozen.