The moisture content of squid is relatively high, which is about 75-80%. During the whole drying process, about 60% of the moisture content will be evaporated, and most of the aquatic products are heat-sensitive materials.
(1) Temperature control
Drying process is generally required to be carried out in a relatively low-temperature environment. In order to avoid protein denaturation, to prevent from rapid growth of bacteria and destruction of drying quality, it is advisable to set the temperature at 35℃-45℃. Rapid drying will cause the squid surface to crust, which will not facilitate the migration of moisture inside to the surface and will result in false drying. Therefore, the drying speed of the heat pump dryer must not be too fast. Set the temperature at about 40°C and use a negative pressure fan in a closed insulation room to increase the circulating air volume and wind speed inside the room, making the drying process uniformly and slowly.
(2) Wind speed control
Maintaining a large circulating air volume and a higher wind speed could make a full contact between the squid and the air, and the water vapor evaporated from the squid is taken away under the action of the circulating wind, afterwards, the water vapor is condensed and filtered out of the room through the equipment unit.
(3) Humidity control
As squid and cuttlefish not only has a large amount of water, but also contains water in its fat, dehydration is more difficult than other types of materials. Controlling its dehydration rate and its dehuminification rate is one of the important factors that determine the quality of squid and the color of the dried seafood. To drying squid or cuttlefish, it is important to avoid moisture staying on the surface of the squid body, because the moisture will hinder moisture removal and will cause bacteria to grow.