Research On Solar Drying Efficiency Of Scallops

The poor sanitation, the long time, the poor quality of open sun drying of the scallop column, and the large energy consumption and serious pollution problem of electrothermal coal-fired hot air drying, these had become the main problems which restrict the development of the drying scallop column industrialization. The solar energy drying as a kind of conservation, environmental protection energy, aroused people’s concern. This experiments, with the bohai bay scallop column as raw material, studied the different salt concentration pre-cooking solution on the effects of the dry scallop column; using response surface box-benkhen experiment, choosed the optimized process of solar drying; compared and analyzed the different drying methods of scallop column the physical properties, chemical properties and energy consumption, selected the optimum method of the drying scallops column.1. The effects of different concentrations of salt pre-cooking solution for the drying scallops column were studied for measuring drying characteristics, nutritional content and energy consumption, determined the salt concentration of solar drying. The results showed that different concentrations of salt pre-cooking solution had significant effect on water content of scallop column, when the drying temperature was 55℃, the salt concentration was 3%, the texture and color parameters was more significant and better than that group without salt pre-cooking solution treatment(P<0.05), the scallop column had moderate hardness, the lower color change, the good appearance quality; sensory score value of the scallop column was 8.84±0.28, significantly higher than that without salt pre-cooking solution processing of sensory score value was 6.31±0.23.2. The effects of solar drying temperature, wind speed, relative humidity parameters on the scallops column characteristics were studied for measuring the drying characteristics and energy consumption, preliminary made a basic research for drying optimization conditions of scallop column. The results showed that the higher solar drying temperature and wind speed, or lower relative humidity, can accelerate the drying rate, shorten the drying time; Temperature and relative humidity had significant effect on the texture of scallop column, when the temperature of 55 ℃, relative humidity of 7 %RH, hardness value was significantly better than the precooked group(P<0.05); Three parameters had significant effect on shrinkage rate of scallop column; The temperature had significant effect on energy consumption of scallop column, when the drying temperature of 55℃, energy consumption is 0.9 kw·h, significantly lower than other temperature processing. Considering these indicators, solar drying temperature range was(40~70) ℃, wind speed should not be higher than 12 m/s, the humidity should not be too low.3. The effects of drying time and drying energy consumption of drying temperature, wind speed and relative humidity for scallop column solar drying process were carried out and identified more suitable conditions of solar drying technology. This part set up the regression model about factors drying temperature(X1), wind speed(X2), relative humidity(X3) on the drying time(Y1) and drying energy consumption(Y2), and the model was significance, the R2 of drying time and drying energy consumption model is 0.9695 and 0.9559, respectively is fitting. The corresponding relation of the various factors and the response value were studied, determined the most suitable conditions of solar drying technology is: the drying temperature is 56.83 ℃, wind speed 8.87 m/s, relative humidity 10.26 % RH.4. The effects of the four different drying methods of the scallops column were carried out, determined the solar drying method for scallops column is suitable for industrialized production. Results showed that the open sun drying, hot air drying, solar drying and infrared drying had significant difference on drying time(P<0.05),which is respectively 50 h, 9 h, 9 h, and 7 h, the time of open sun drying is the longest; Four drying methods had significant difference on the texture parameters, solar drying was better than other treatment, which hardness is(61.73±3.73)N, and solar drying > hot air drying > open sun drying > infrared drying; Four drying methods had significant difference on shrinkage rate, solar drying was better than other treatment, which the lowest shrinkage rate was 42.12%, and solar drying < open sun drying < hot air drying < infrared drying; Four drying methods had significant difference on crude protein, the infrared drying of protein content was significantly higher than others, which is(72.40±0.01) g/100 g and infrared drying > solar drying > hot air drying > open sun drying; Four drying methods had significant difference on energy consumption, the open sun drying do not need consume energy, significantly lower than other treatment and infrared drying > hot air drying drying > solar drying > open sun drying.. Considering these indicators, the solar energy drying, which had low energy consumption, protected environment, had better drying quality, was more suitable for industrial production.