Grape fruit quick-frozen fresh-keeping process

In addition to refrigerated fresh grapes, fresh grapes can be frozen and preserved. Compared with cold storage, the grape has a long shelf life for quick-freezing, no preservatives added, and it is convenient and hygienic. It can be supplied for an annual period, and is not subject to variety restrictions. Grapes of different flavors can be quickly frozen. China has produced quick-frozen and peeled grape fruit for foreign manufacturers to produce fruit juice drinks. However, during the process of the process, the grapes need to be peeled, the nutritive components are inevitably damaged, and they are easily discolored. In order to increase the supply of varieties of grapes, the process of quick-freezing and preservation of grape fruit was explored to form the following processes: Raw materials → picking → cleaning, draining → disinfection, rinsing, draining → threshing → color protection, draining, cooling → quick freezing → packaging → inspection , frozen. Operational requirements 1. The raw materials require that the grapes be fully matured, and the soluble solids must be more than 14.5%. The ear is tight, fresh and free of pests. 2. Carefully remove the diseased grains, softened grains, blue grains and impurities on the grape ear. 3. Wash, Drain Rinse repeatedly with tap water for 5-6 times, then drain. 4. Disinfection, washing, draining Wash the drained grapes and soak them in 1:250 pasteurizing solution or 0.05% potassium permanganate solution for 4-5 minutes, then rinse with tap water 4-5 times. Drain. 5, threshing gently remove the fruit by hand, requires no fruit stems, no pull the fruit. At the same time, further reject the unqualified fruit. 6, color protection, drain, cooling The grape fruit in 1% NaCl + 0.1% citric acid solution or 0.1% Vc solution soak for 4-5 minutes, color protection. Then drain the water and quickly cool to 0-5 °C. 7. Freeze using a fluidized freezing device to freeze. In this way, the grape granules are suspended and freeze when they do not adhere to each other. The cold air temperature is generally -35 to -40°C. Since the grape granules are in suspension, the entire surface is in contact with the cold air, and the wind speed between the chilled products is 1.5. -5 m/s, the freezing speed is very fast. Within 5-10 minutes, the food can be frozen to -18°C and the freezing quality is good. It can also be frozen with still air. If the water is drained, the frozen grape grains will not stick to each other, but it will take longer. 8. Packing is performed below -5°C to avoid recrystallization. Because quick-frozen grapes are ready-to-eat foods, the hygiene requirements are strict, and the packaging room is sterilized by ultraviolet light 1 hour before packaging. All tools, work clothes, shoes, caps, etc. must be disinfected. Workplaces and workers must strictly implement food hygiene standards. 0.06-0.08mm non-toxic polyethylene plastic film with low air permeability and low temperature resistance is used for inner packaging. It is vacuum-sealed and sealed. The specifications can be selected according to the market consumer demand, and then loaded into cartons. Print the name, specifications, weight, date of manufacture, storage conditions and period, lot number, and manufacturer on the carton. 9. To inspect and freeze each batch of quick-frozen grapes, a random sample inspection shall be conducted according to the GB standard, including sensory inspection, sanitary inspection and physical and chemical inspection. The eligible persons shall be frozen immediately, and the frozen storage temperature shall be -18 to -20°C.