Influence of infrared drying on storage characteristics of brown rice (original) (raw)

Study of drying kinetics and qualities of two parboiled rice varieties: Hot air convection and infrared irradiation

2012

15 Effect of infrared (IR) and hot air (HA) drying conditions on drying kinetics of 16 Leb Nok Pattani (LNP) rice and Suphanburi 1 (SP 1) parboiled rice and their qualities 17 were studied. Initial moisture content for LNP and SP 1 rice was of 54±1 and 49±1% 18 dry-basis, respectively. Drying temperatures of 60-100C, IR power of 1.0 and 1.5 kW 19 and hot air flow rate of 1.0±0.2 m/s were used for experiments. The results show that 20 HA and IR parboiled rice drying can maintain high head rice yield (HRY) and IR drying 21 with 1.5 kW provided highest HRY value. Additionally, the qualities analysis showed 22 that whiteness, water absorption, cooking time and pasting property were significantly 23 different compared to reference samples. The specific energy consumption of parboiled 24

COMPARATIVE STUDY BETWEEN HOT AIR AND INFRARED DRYING OF PARBOILED RICE: KINETICS AND QUALITIES ASPECTS

The objectives of this study were to analyze the effects of drying employing three different heat sources on drying kinetics and to evaluate qualities of parboiled rice after drying. Drying temperature was varied between 60 and 100C. Power of infra-red (IR) heat source was fixed at 1,000 and 1,500 W and air flow rate was fixed at 1.0 0.2 m/s. The three drying strategies composed of hot air (HA), IR and combined HA + IR drying. The experimental results were simulated using various equilibrium moisture content models and the mathematical drying model for prediction of drying kinetics and evaluation of effective diffusion coefficient (Deff) followed by Fick's law of diffusion. The results revealed that Deff values of HA and IR drying were in the range of 10-12 –10-11 m 2 /s and relatively depended on temperature. For quality evaluation, conclusions reached that head rice yield using HA + IR drying had the highest value, while yellowness and whiteness of the par-boiled rice are significantly affected by drying condition (P > 0.05). These results suggested that combined hot air and infrared (HA + IR) drying offers a great potential for preserving Leb Nok Pattani parboiled rice. Drying kinetics and quality aspects determined that IR drying is more efficient than the other drying method. However, the color degradation in the grain kernel is an issue for quality measurement.

Effect of hot air assisted infrared drying on drying characteristics and quality of rice bran pellets

MATEC Web of Conferences, 2018

The objective of this study was to determine drying characteristics and quality of rice bran pellet subjected to hot air assisted infrared (HA-IR) drying at different levels of infrared (IR) intensity (750 – 3750 W/m2) and air temperature (40 – 80°C). The rice bran pellets were dried from 0.18 to 0.08 g water/g dry matter. The maximum drying rate (DR) and drying time were in the ranges of 0.0030 – 0.0165 g water/g dry matter·min and 8 – 54 min, respectively. Higher IR intensity and air temperature resulted in greater maximum DR and shorter drying time. The same trend was also observed for the effective moisture diffusivity (Deff) values which were between 0.3103×10-7 and 2.7603×10-7 m2/s. As compared to the commercial reference sample of dried rice bran pellets, the products of this study had higher oil content and lower FFA content. The oil content was affected by IR intensity only while the FFA content was affected both by IR intensity and air temperature. HA-IR drying could impro...

Temperature Profile and Moisture Content during Infrared Drying of Pelletized Rice Bran

2017

This paper presented the experiment concerning the effect of height between infarred tube and the heating surface.The height of 20 cm, and 30 cm were selected. Height of 20 cm exhibited the most suitable distribution of temperature contour of 70oC. Two tubes with 18 cm, 24 cm and 30 cm distance between tubes was also studied. Contour plot of two tubes at the distance of 24 cm showed well distributed temperature of 70oC. Drying of pelletizied rice bran with different power current of 0.8, 0.7, 0.6, and 0.5 A at 20 cm height gave the results at moisture content of 8% (dry basis) with drying time of 15 min, 20 min, 24 min and 29 min respectively. With two tubes heating, time to dry rice bran pellet at 0.8 A and 0.6 A were 12 min and 16 min. It can be concluded that drying condition for pelletized rice bran from 18% to 8% moisture content took 15 min at the infrared power current of 0.8 A with 20 cm height for 1 tube and 12 min for 2 tubes at 24 cm aparted.

Vibratory bed assisted infrared drying of parboiled rice and its rice bran stability

MATEC Web of Conferences, 2018

The purposes of this research were divided into two parts: (1) to determine the drying characteristics and quality of parboiled paddy undergoing vibratory bed assisted infrared (VIR) drying, and (2) to study the stability of rice bran from the VIR-dried parboiled paddy. Infrared (IR) drying and hot air (HA) drying were applied for comparison purpose. For the experiment 1, VIR drying of parboiled paddy provided the best drying characteristics with the shortest drying time of 50 min and the maximum drying rate of 0.00146 g water/g dry matter·min. VIR drying also produced the greatest head rice yield of 61.3%. The experiment 2 presented that rice bran from VIR-dried parboiled paddy had the highest oil content of 0.256 ± 0.041 g/g dry matter and the most stable in term of minimum change in free fatty acid (FFA) content. The increase in FFA during storage for 14 days was 0.36%. However, the increases in FFA of rice bran from IR-and HA-dried parboiled rice and normal rice were 0.38, 1.36,...