How to Dry Grape with Kinkai Dehydrator
HOW TO DRY GRAPE WITH KINKAI DEHYDRATOR
1. WARMING UP
During the drying process, if the grape directly enters a high-temperature environment suitable for sugar conversion, a huge temperature difference causes the grape to undergo a biological protection reaction, the epidermal cell pores contract, the crust hardens, and the moisture inside the grape is prevented from evaporating. Therefore, in the early stage of grape drying, sufficient preheating is needed, and the temperature is gradually increased to prepare for a large amount of water evaporation. Keep it for 6 to 10 hours at 35℃. When the temperature of the grape reaches 45℃, it will be slightly hot. After 7 to 8 hours, the grape body will wrinkle when it is pressed hard; when the temperature of the grape reaches 45 to 48℃, a layer will appear drop of water on the surface of the grape.
The large amount of free water inside the grapes is evaporated. At this time, the temperature must be increased to reach 65℃ in the drying room within 8 to 12 hours, and should not exceed 70℃. In order to evaporate a large amount of water, pay attention to dehumidification, and keep the indoor temperature from changing greatly, so as to continuously evaporate the water. When wrinkles appear on the surface of the grape fruit, it indicates that the grapes are dry normally.
When the temperature inside the grape is uniform, this stage can be completed in 6 hours. Because there is not much moisture in the grapes in the late period, special attention should be paid to temperature control, not too large, preferably 50℃. At this time, the relative humidity has also dropped, and if it is higher than 60%, it can be slightly drained. With the gradual equilibrium of the moisture in the grapes, the purpose of drying is achieved. Take care to remove the dried samples in time.
The baked grapes must be ventilated and heat-dissipated, and can only be stacked after cooling. If the grapes just unloaded from the drying room are stacked in the warehouse, because the grapes themselves have a lot of sugar, under the action of heat, the sugar is easily fermented and deteriorated. The original pectin in the grape will also decompose the fruit gum and pectin acid. The grapes will inevitably become a mess, and the sugar in the grapes will change, sour filaments will appear, which will destroy the grapes. Therefore, after baking, it must be thoroughly cooled before it can be stored.