Picking: It is a fruit and vegetable processing process. The principle is to select the best and remove the inferior. All raw materials that are not suitable for the processing requirements must be removed, such as the old pods of green beans, residual, inferior and rotten, moldy fruits, etc. Have to be removed.
Sorting: Including the grading of the size, weight and quality of raw materials. Size classification: It is convenient for subsequent processing and makes the product uniform. Quality classification: to ensure that the specified quality requirements are met. Including indicators such as color, maturity, shape, and hardness. There are two methods for the size classification of raw materials, namely manual classification and mechanical classification. Manual grading is performed manually, but it also requires certain templates, such as apple grading; mechanical grading such as vibrating screen (beans, peanuts), drum classifier (hawthorn), separation conveyor, weight classifier, etc.
Washing (Washing or Cleaning): The content of washing includes washing away raw material contaminated mud and sand, microorganisms (0.1% KMnO3 or 600ppm bleaching powder), and pesticide residues (0.5-1.5% HCl). The washing water should also meet the drinking water requirements. There are two washing methods: manual and mechanical. There are three main washing methods in form, namely washing with flowing water (manual stirring or compressed air stirring), friction washing (drum washing) and spray washing, which should be flexible according to the characteristics of different raw materials. select.
Peeling, cutting, core removal and core removal: The methods of peeling include manual peeling, mechanical peeling, thermal peeling, frozen peeling, lye peeling, and enzymatic peeling. The core or core should be removed during processing of pitted raw materials, such as peach, apricot, apple, pear, hawthorn, etc. The cutting of peach is "cutting peach", which is done manually or with a peach splitting machine along the suture line, and then digging the core with a spoon-shaped core knife; the cutting of apricot is "cutting shape", after cutting according to the suture line, Apricot cores can be separated with one twist; apples, pears, etc. are cut with a ring-shaped core knife (need to be cleaned to avoid browning); hawthorn cores are cored with a pitting device, and a cylindrical pitting device.
Blanching: In addition to pickling, raw materials for sugar, dried, canned, and quick-frozen generally need to be blanched. Blanching is the process of heating fresh fruit and vegetable raw materials in hot water or boiling water or atmospheric steam at a higher temperature for a certain period of time.
Color protection treatment: refers to the protection and maintenance of the color of raw materials. It is generally used in the process of fruit and vegetable processing, especially after the raw materials are peeled, cut, and crushed. For colored materials, the original color should be maintained as much as possible, and for white materials, browning should be prevented. During the processing of fruits and vegetables, special attention should be paid to the color protection of white raw materials, such as apples, white peaches, pears, etc.; vegetables such as lotus root, burdock, potatoes, etc., are easy to change color after being chopped and placed in the air. The content is related to the activity of polyphenol oxidase.