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

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

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