The study of quality attributes of parboiled rice during steaming process with revolved sieve

The steaming process with revolved sieve was studied as a function of steaming time and revolution velocity. The quality of parboiled rice in terms of thermal property, head rice yield and color was investigated and compared to the conventional steaming process such as fixed sieve. The experimental results showed that the steaming process with revolved sieve had advantage over the steaming process with fixed sieve. It led to a steamed sample with higher DG higher head rice yield and lower whiteness value. The required steaming time for a regularity quality by a steaming process with revolved sieve was also shorter. Moreover, the steaming time affected the qualities of parboiled rice. The long steaming time provided the higher DG and head rice yield and lower whiteness value of parboiled rice. Considering revolution velocity, it was found that the revolution velocity did not affect the qualities of parboiled rice. However, the revolution velocity of 5 rpm with steaming time of 5 min provided the difference of quality at each layer

The study of the drying kinetic and the cutting performance in dried betel nut production machine

Betel nut kernel is an important raw material in the leather and dye industries. The quality control after harvest is necessary, especially, the excess moisture content may cause the spoilage. Therefore, this research aims to study the betel nut fruit drying using infrared ray combined with the rotated trays. The betel nuts fruits were placed in rotated trays. These trays were installed within drying chamber which had the infrared rod in 2 positions namely the center and wall of drying chamber. The drying temperature used at 80, 100 and 120°C. The revolution speed of tray was set at 2, 4 and 6 rpm. The dried betel nut fruits were cut into 2 pieces at the blade speed of 25, 30 and 35 rpm. The experimental results showed the installation of infrared rods at the center could decrease the moisture content faster than at the wall. The betel nut fruit should use the drying temperature of 120°C for 10 h and the revolution speed of 2 rpm. The blade speed of 30 rpm gave the most cutting performance about 76%. The colour of dried betel nut kernel (L*, a* and b*) did not significantly difference with the commercial betel nut

Parboiled germinated rice production using a new method

The process complexity is the main problem for parboiled germinated rice (PGR) production. The PGR production using the new method (germinating and drying using hot air fluidized bed combined with halogen lamp) can decrease the complexity of process and also provided the good quality of PGR when comparing with PGR production using traditional method (germinating, steaming and drying using hot air fluidized bed). The new method provided the higher drying rate, leading to faster decrease of moisture content and higher increase of grain temperature. This caused the lower whiteness index. It also provided the lower degree of gelatinization. However, the percentage of head rice yield of PGR with new method was not significantly different when comparing with PGR production using traditional method. For Specific Energy Consumption (SEC), the PGR production using the new method provided the lower SEC value than PGR production using traditional method

Optimization of sorting efficiency of size grading machine using oscillating sieve with swing along width direction

Grading according to the sizes is an important value adding technique for Robusta green coffee bean. Mechanical grading can increase the sorting efficiency and the need for workers is decreased. Therefore, the sorting efficiency of size grading machine was optimized based on inclined angle and oscillating speed. The Response Surface Methodology (RSM) combined with central composite design (CCD) was applied in the optimization of the sorting efficiency of the machine. A quadratic model was suggested for the sorting efficiency of size grading machine. The results showed that the optimum operating parameters for size grading machine using oscillating sieve with swing along width direction were inclined angle of 5.06 degree and oscillating speed of 183.28 rpm with a sorting efficiency of 79.99%. The high correlation coefficient (R2 = 0.9676) indicated that the data predicted using RSM were in good agreement with the experimental results