The objectives of this research were to study the effect of hot air velocity on the changes of the moisture content and temperature of preserved tomatoes undergoing combined conveyor system and hot air drying. Specific energy consumption physical properties in term of color and shrinkage and sensory evaluation of dried preserved tomatoes were also investigated. The preserved cherry tomatoes were dried at a drying temperature of 80oc and hot air velocity of 2 and 4 m/s until the moisture contents of the preserved tomatoes were lower than 18% wet basis. The experimental results showed that the hot air velocity had effect on the changes of the moisture content and temperature of preserved tomatoes. Specific energy consumption total color difference shrinkage percentage and sensory evaluation results of dried preserved tomatoes of the hot air velocity of 2 and 4 m/s were not significantly different (P>0.05).Moreover the dried preserved tomatoes obtained from this research had significantly lower sensory scores in term of color and appearance than those obtained from the local market (P≤0.05). However sensory scores in term of flavor texture and overall preference of the dried preserved tomatoes obtained from this research and the local market were not significantly different (P>0.05).

The objectives of this research were to determine the suitable times of pork slices drying using microwave followed by hot air and to find specific energy consumption during drying. The physical characteristic (color and hardness) and the sensory test of dried pork slices were also investigated. Pork slices with the sizes of 50x50x1.3 and 50x50x2.2 millimeters were dried using the microwave at the powers of 160 320 480 640 and 800 watts until the samples did not burn during drying. Then the samples were dried using hot air at a temperature of 110oC until the moistures of the samples were lower than 20% dry basis. Based on the experimental results it was found that the suitable times of the samples drying using microwave were 50-600 seconds which depended on the microwave powers and the pork thicknesses. In hot air drying period drying times of the samples with thicknesses of 1.3 and 2.2 millimeters were 30 and 45 minutes respectively. The microwave powers had no significant effect on the redness (a value) and yellowness (b value) of dried pork the hardness of dried pork and the specific energy consumption (P<0.05). The pork thicknesses had the significant effect on the lightness (L value) and yellowness (b value) of dried pork the hardness of dried pork and the specific energy consumption (P<0.05). Moreover sensory scores of the dried pork obtained from this research were close to those obtained from the local market.

This research aims to study the appropriate drying condition and extraction solvent for extracting protein and antioxidants from the porcine placenta. Three levels of drying temperature were used in this study which were 50 60 and 70ºC the result shows that the best drying condition for porcine placenta was 70ºC for 4 hours because this condition provided the least drying time and the lowest moisture content of porcine placenta (3.80±3.36% dry basis). After that the fresh and dried porcine placenta were extracted by using three solvents which were deionized water (DI) phosphate buffered saline (PBS) and hexane. The efficiency of extraction was investigated by measuring the crude protein and antioxidant of the porcine placenta. It was found that there was no protein and antioxidant in fresh and dried porcine placenta extracted by hexane. However the protein was found as 0.05±0.01 and 0.04±0.01 mg of bovine serum albumin/100 mg fresh for fresh porcine placenta and 0.12±0.030 and 0.07±0.016 mg of bovine serum albumin/100 mg fresh for dried porcine placenta extracted by DI and PBS respectively. In additional the antioxidant was found as 1.13±0.03 and 1.29±0.04 mg of trolox/100 mg fresh for fresh porcine placenta and 3.37±0.02 and 3.59±0.01 mg of trolox/100 mg fresh for dried porcine placenta extracted using DI and PBS respectively.

The aim of this research was to model the hot air-drying (HAD) of fermented soybean meal (FSBM) containing probiotic Enterococcus faecium . The HAD was performed to reduce the moisture content of the FSBM. The effects of drying temperature on cell viability and moisture content were investigated. Moisture content decreased rapidly with increasing drying temperature. This probiotic strain’s cell viability slightly decreased at drying temperatures lower than 50°C and was greatly decreased at 55°C. Four mathematical models were applied to describe its drying kinetics revealing that the Page model was the best fit for characterizing the drying kinetics during drying of FSBM with a coefficient of determination (R2) of 0.9996. Moreover the Page model provided the lowest root mean square error (RSME) and chi-square (X2) and the highest modeling efficiency

This research objective was to apply thermoelectric module model TEC12710 as a preheater and dehumidifier for red chilies dryer. The heat side and cool side of Thermoelectric module affected by supplied electricity were used to produces the low humidity and warm air in preheater before charging to the main electric heater of dryer. Fresh red chilies were selected as a sample in the prototype testing during the use of preheater assisted main heater and using only main heater. The test results are compared with the sample dried under the natural sun drying. The experimental results show that the preheater can condense the moisture in air with the highest MER of 0.083 kgwaterh-1 at cold side of thermoelectric module and can heat the air up in 10°C of temperature with hot side of thermoelectric module. The final moisture content of sample is only 10%wb with the slightly changed in color when compared with the sample from sun drying. The using of preheater with main heater gives a higher specific moisture extraction rate lower specific energy consumption 14 MJ energy used and can dry faster than 10 h when compared with the using of only main heater.