Experiment result data can be calculated to obtain the value of fish drying characteristics as shown in Table 1. The influence of drying air temperature change at a constant velocity is shown in the Figs. 3 and 4. Fig. 3 shows that the moisture content decreased with increasing temperature. Brian and Gorman [18] showed the same result but it is mentioned that the increase in air temperature may also increase the evaporation of volatile material. Fig. 4 shows warming period phenomenon before constant drying rate period. The higher drying air temperature causes shorter warming period. Data in the Fig. 4 explain why lower hot air temperature requires more time of drying to achieve the same moisture content. This is because when lower air temperature is implemented, it will spend more time for warming period. As result of it, the duration of constant drying rate period which is defined by the time to attain M C decreases with increasing drying air temperature whereas drying constant k1 and k2 increased. In the experiment of drying air temperature 70 °C, relative humidity of drying air was measured at 8% meanwhile for other experiment at 60 °C, 50 °C and 40 °C are 11%, 16% and 27%, respectively. Higher temperature of drying air causes relative the humidity decreases, these cause vaporizations of water from fish surface into the air faster. Dry air picks up moisture from the surface of fish faster than humid air. Higher drying air temperature also causes higher the drying capability. Drying capability of air can be evaluated from adiabatic evaporation process. The
Experiment result data can be calculated to obtain the value of fish drying characteristics as shown in Table 1. The influence of drying air temperature change at a constant velocity is shown in the Figs. 3 and 4. Fig. 3 shows that the moisture content decreased with increasing temperature. Brian and Gorman [18] showed the same result but it is mentioned that the increase in air temperature may also increase the evaporation of volatile material. Fig. 4 shows warming period phenomenon before constant drying rate period. The higher drying air temperature causes shorter warming period. Data in the Fig. 4 explain why lower hot air temperature requires more time of drying to achieve the same moisture content. This is because when lower air temperature is implemented, it will spend more time for warming period. As result of it, the duration of constant drying rate period which is defined by the time to attain M C decreases with increasing drying air temperature whereas drying constant k1 and k2 increased. In the experiment of drying air temperature 70 °C, relative humidity of drying air was measured at 8% meanwhile for other experiment at 60 °C, 50 °C and 40 °C are 11%, 16% and 27%, respectively. Higher temperature of drying air causes relative the humidity decreases, these cause vaporizations of water from fish surface into the air faster. Dry air picks up moisture from the surface of fish faster than humid air. Higher drying air temperature also causes higher the drying capability. Drying capability of air can be evaluated from adiabatic evaporation process. The
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