Grape processing steps
1.you should use 1.5-4.0% of sodium hydroxide solution to remove waxy and harmful microorganisms attached to the grape peel, and at the same time, the Washing and decontamination processcan disinfect the grape and make small cracks in the peel to facilitate water evaporation and promote drying.
2.After mixing 0.6 g of potassium hydroxide and 6 ml of 95% ethanol, add 3.7 ml of ethyl oleateandshake well, then add 1000 ml of 3% potassium carbonate aqueous solution, stirring it while pouring to obtain an alcohol-soluble oil-alkali emulsion .
Grape drying process
The loading capacity of the tray is 14-20kg/㎡, the initial temperature is set to 45°C-50°C, and the final temperature is set to 70°C-75°C. The drying time is about 42-60 hours. During the drying process, the dehumidification capacity of the system should be great, and the dehydration rate should reach 70%. It remains green when it has been fully dried. When the grape has been dried moderately, it will become soft, no juice oozing out when pressed by hand. The moisture content is 15-17%, and the drying rate is 3:1-4:1.