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microwave area causes an uneven temperature distribution in the drying material
(Duan et al. 2010; Dolan and Scott 1994).
Cabinet Drying
Cabinet dryer is used with other drying technologies. This type of drying is more
flexible as it provides drying without focusing on the problem of air, season or animals. It is a typical cabin filled with a shallow tray. To ensure optimum drying, hot
air flow occurs throughout the area inside the cabinet (Chong et al. 2015).
Combined Methods
A combination of drying methods can be used to avoid the disadvantages of a single
drying method and combine the advantages of various drying methods. Duan et al.
(2007) examined the effects of the combined use of different drying methods on the
rehydration and textural properties of the product. For this purpose, drying of sea
cucumber (Stichopus japonicus) was tried with the combination of freeze drying
and microwave frying, and the combination of freeze drying and microwave vacuum drying. With the combination of freeze drying and microwave vacuum drying,
more acceptable quality and better drying efficiency were achieved.
Combination of infrared radiation and freeze-drying pre-treatment was found to
be effective for drying the fresh sea cucumbers. The drying time of sea cucumbers
with infrared radiation pre-treatment is shorter than that of raw materials without
pre-treatment (Mamatov et al. 2019).
Far Infrared Radiation Drying
In far-infrared radiation drying, which electromagnetic wave energy is absorbed
directly by dried food, the temperature distribution in the product (FIRD) is relatively uniform. This kind of uniform temperature distribution accelerates the drying
rate and reduces the internal resistance in the surface hardening seen in the airdrying method. Due to the high drying rate, a higher quality product is obtained and
consumes less energy. It is an energy-saving method (Moon et al. 2014). Far-infrared
radiation drying method has been used to dry other foods such as mushroom (Yeon
et al. 2004), blueberry (Shi et al. 2008), banana (Nimmol et al. 2007), onion
(Marinos-Kouris and Maroulis 1995) and barley (Afzal and Abe 2000). A limited
number of studies have been carried out on drying sea cucumber with this method.
Moon et al. (2014) examined the effects of far-infrared radiation drying temperature
on sea cucumber (Stichopus japonicus) drying rate and compared them with the hot
air-drying method. At the end of this study, it has been found that the far infrared
radiation drying reduces the drying time and a higher quality product is obtained
compared to the air-drying method. Zhao et al. (2018) tried to dry sea cucumber
using far infrared drying method. They found that drying temperatures had a significant effect on relative moisture content, drying rate, shrinkage rate and rehydration rate.
4.3 Sea Cucumbers
microwave area causes an uneven temperature distribution in the drying material
(Duan et al. 2010; Dolan and Scott 1994).
Cabinet Drying
Cabinet dryer is used with other drying technologies. This type of drying is more
flexible as it provides drying without focusing on the problem of air, season or animals. It is a typical cabin filled with a shallow tray. To ensure optimum drying, hot
air flow occurs throughout the area inside the cabinet (Chong et al. 2015).
Combined Methods
A combination of drying methods can be used to avoid the disadvantages of a single
drying method and combine the advantages of various drying methods. Duan et al.
(2007) examined the effects of the combined use of different drying methods on the
rehydration and textural properties of the product. For this purpose, drying of sea
cucumber (Stichopus japonicus) was tried with the combination of freeze drying
and microwave frying, and the combination of freeze drying and microwave vacuum drying. With the combination of freeze drying and microwave vacuum drying,
more acceptable quality and better drying efficiency were achieved.
Combination of infrared radiation and freeze-drying pre-treatment was found to
be effective for drying the fresh sea cucumbers. The drying time of sea cucumbers
with infrared radiation pre-treatment is shorter than that of raw materials without
pre-treatment (Mamatov et al. 2019).
Far Infrared Radiation Drying
In far-infrared radiation drying, which electromagnetic wave energy is absorbed
directly by dried food, the temperature distribution in the product (FIRD) is relatively uniform. This kind of uniform temperature distribution accelerates the drying
rate and reduces the internal resistance in the surface hardening seen in the airdrying method. Due to the high drying rate, a higher quality product is obtained and
consumes less energy. It is an energy-saving method (Moon et al. 2014). Far-infrared
radiation drying method has been used to dry other foods such as mushroom (Yeon
et al. 2004), blueberry (Shi et al. 2008), banana (Nimmol et al. 2007), onion
(Marinos-Kouris and Maroulis 1995) and barley (Afzal and Abe 2000). A limited
number of studies have been carried out on drying sea cucumber with this method.
Moon et al. (2014) examined the effects of far-infrared radiation drying temperature
on sea cucumber (Stichopus japonicus) drying rate and compared them with the hot
air-drying method. At the end of this study, it has been found that the far infrared
radiation drying reduces the drying time and a higher quality product is obtained
compared to the air-drying method. Zhao et al. (2018) tried to dry sea cucumber
using far infrared drying method. They found that drying temperatures had a significant effect on relative moisture content, drying rate, shrinkage rate and rehydration rate.
4.3 Sea Cucumbers