• Journal of Biosystems Engineering
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• v.27 no.1
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• pp.45-50
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• 2002

This study was performed to develop thin layer drying equations fur short grain rough rice using far-infrared ray. Thin layer drying tests was conducted at four far-infrared ray temperature levels of 30, 40, 50, 60$^{\circ}C$ and two initial moisture content levels of 20.7, 26.2%(w.b.). The measured moisture ratios were fitted to Lewis and Page drying models by stepwise multiple regression analysis. Half response time of drying was affected by both drying temperature and initial moisture content at drying temperature of below 40$^{\circ}C$, but at above 40$^{\circ}C$ was mainly affected by drying temperature. Experimental constant(k) in Lewis model was a function of drying temperature, but K and N in Page model were function of drying temperature and initial moisture content. Moisture ratios predicted by two drying models agreed well with experimental values. But in the actual range of drying temperature above 30$^{\circ}C$ Page model was more suitable for predicting of drying rates.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.635-640
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• 2006

This study was conducted to determine the effect of far infrared ray drying on the microbial and quality changes of vacuum packaged waxy corns, such as microbial growth, rehydration, color differences, weight loss and hardness during the storage at $4^{\circ}C$ and $25^{\circ}C$ for 7 months. After far infrared ray drying for 6 hours at $60^{\circ}C$, 2.32 log CFU/g of total microbial counts in raw waxy corns was enumerated, but no microorganism was detected in steamed or sugar-treated waxy corns. However, no microorganism was observed in all treatments except for control samples until 3 month storage at $4^{\circ}C$, whereas steamed and sugar-treated waxy corns showed 2 and 2.7 log reduction compared to that of control after 3 month storage. Yeasts and molds were more resistant than bacteria against far infrared ray drying at the same conditions. Similar results were observed in $25^{\circ}C$ storage. The degree of gelatinization in raw waxy corns far infrared ray drying changed from 98% to 96.2% after 7 month storage at $4^{\circ}C$, whereas steamed waxy corns with far infrared ray drying changed from 81.14% to 58.73%. Water contents in sugar-treated waxy corns with far infrared ray drying gradually reduced compared to steamed waxy corns as drying time increased. The L values in raw waxy corns far infrared ray drying increased as drying time increased, but L values in steamed or sugar-treated waxy corns significantly reduced after 12 hour far infrared ray drying. Hardness in raw waxy corns was higher than in steamed or sugar-treated waxy corns before storage, but similar hardness was observed between raw- and sugar-treated waxy corns after 9 hour drying. This results showed that the microbial reduction, the enhancement of shelf life and quality establishment of steamed or sugar-treated waxy corns could be maximized by using far infrared ray drying.

• Food Science and Preservation
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• v.3 no.2
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• pp.137-143
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• 1996

In order to produce the high-quality of dried red pepper with respect to a color and a taste we developed a automatic drier equipped with combined several heat energies(ADCHE). and compared the quality of ADCHE-treated red pepper with that of the pepper treated with conventional dryings such as natural, hot-air, and far-infrared ray dryings. The results obtained were as follows : (1) The contents of capsanthin varied significantly with drying methods within the range of 1.7 to 6. 4mg/g dry weight. The capsanthin level of red pepper treated with far-infrared ray drying was higher than that of the pepper treated with ADCHE showed the highest at 51.46mg/g dry weight of three drying methods. (2) As a result of determination of color intensity of-red-pepper using-a colorimeter, the red color intensity of the peppers was affected by drying methods irrespective of drying temperature, and especially a value of red pepper treated with ADCHE was appeared to be 19. 1, indicated that this pepper have the most bright color intensity. (3) The contents of soluble browing subatances increased with a increase in drying temperature, but L* value of red pepper treated with ADCHE was appeared to be 0.187, indicated that this red pepper have the most clear red color (4) The changes of capsanthin level of red pepper according to drying methodes did not show significantly, but generally a decreasing rate of capsanthin levels were lower in that order ADCHE

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.937-946
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• 1996

A Far Infrared Ray (FIR) dryer was designed , constructed and tested for red pepper , lycium chinese, and mushroom (Cortiellus shiitake ) drying , and the results were compared to the heated air dryer at the same condition. In the FIR dryer, three different panel materials , galvanized, copper and stainless steel, were used and no ceramic coating and those with ceramic coating (three panels) were 58% , 56%, 64%, and 88% , respectively. The drying times of lycium chinese and mushroom were shortened in FIR dryer by 6 hrs and 4 hrs compared to the heated air drying, respectively. while to remarkable difference in the drying times was found in the red pepper drying . The quality of products was better in FIR dryer where more red color value for red pepper and lycium chinese and more brightness for mushroom . The drying performance of a FIR dryer was superior in terms of total cost of 80,800 WON /100kg of lycium chinese , reduced by 25% compared to the heated air drying.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.561-567
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• 2000

This study was conducted to determine the effect of far infrared-vacuum drying on the quality changes of Pimpinella bracycarpa, such as drying efficiency (weight loss), color differences, browning degrees, rehydration and sensory evaluation. Wehn Pimpinella bracycarpa was dried for designated time at 5$0^{\circ}C$, 6$0^{\circ}C$ and 7$0^{\circ}C$, drying time of far infrared-vacuum drying was decreased more than 17% compared to that of infrared drying. The color changes increased as drying temperature increased and far infrared-vacuum drying made less color changes than infrared drying. Also, the total microbial counts and the number of yeast and mold were gradually reduced as drying temperature increased and drying time was longer, but there was no significant differences in microbial changes among drying methods. The rehydration rates of Pimpinella bracycarpa increased as drying temperature increased and was better at far infrared-vacuum drying than infrared drying. Also, according to the sensory evaluation after rehydration of Pimpinella bracycarpa, the hihger scores were obtained at lower temperature and far infrared-vacuum drying, especially the color was obtained much hihger score in the far infrared-vacuum drying than infrared drying. Thus, the results showed that drying efficiency and stability of rehydration and color changes was increased and the quality deterioration of Pimpinella bracycarpa could be minimized by using far infrared-vacuum drying.

• Journal of Biosystems Engineering
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• v.41 no.1
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• pp.43-50
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• 2016

Purpose: The present study is aimed at examining the drying characteristics of sea tangle through a combination of microwave and far-infrared drying experiment and finding the optimal drying conditions. Methods: Sea tangle was cleaned and cut into fine pieces (5mm) before they were subjected to combinational drying by microwave and far-infrared ray. The amount of specimen per drying is 2 kg. The finely cut pieces of sea tangle were preheated in a microwave dryer for three different lengths of time (10, 15, and 20 min). Subsequently, they were dried using a far-infrared dryer at tow temperatures ($90^{\circ}C$ and $100^{\circ}C$) at an air velocity of 0.8 m/s until the final moisture content reduced to 10%. Results: Sea tangle dried under the condition of 20 min of preheating in the microwave dryer and drying at $100^{\circ}C$ by the far-infrared dryer. Of the drying models verified in this study, the logarithmic model showed high accuracy with the coefficient of determination $R^2>0.7825$ and RMSE<0.1095. The rehydration ratio of sea tangle was the highest (12.87 g water/g dry matter) under the condition of 15 min of preheating in the microwave dryer and drying at $100^{\circ}C$ by the far-infrared dryer. The energy consumption for the combination of microwave and far-infrared drying was the lowest (4.78 kJ/kg water) under the condition of 20 min of preheating in the microwave dryer and drying at $100^{\circ}C$ by the far-infrared dryer. Conclusions: Considering the drying time, discoloration during drying, rehydration ratio, and energy consumption for the drying of sea tangle, the optimal drying conditions for high-quality sea tangle are 15 min of preheating in a microwave dryer and drying at $100^{\circ}C$ by a far-infrared dryer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.5
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• pp.707-716
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• 2020

Red sea cucumber Stichopus japonicus, was dried using three methods-far-infrared ray, vacuum, and freeze drying and then enzymatically hydrolyzed using nine proteases: Alcalase, Flavourzyme, Kojizyme, Neutrase, Protamex, trypsin, α-chymotrypsin, and papain. In addition, the potential ability of hydrolysates to inhibit lipid accumulation in 3T3-L1 adipocytes was evaluated. The yield of hydrolysates from red sea cucumbers dried using each method was higher than that of the distilled water extract, and protein contents were either similar or higher. The hydrolysates that exhibited inhibitory effects on lipid accumulation, as demonstrated via Oil red O staining, were those obtained by far-infrared ray drying coupled with Alcalase, Flavourzyme, Kojizyme, or Neutrase treatment. In addition to the advantages of far-infrared drying and the characteristics of Flavourzyme, the Flavourzyme hydrolysate of far-infrared-dried red sea cucumber showed the highest inhibitory effect on lipid accumulation. In addition, this hydrolysate significantly decreased the expression of the protein factor fatty acid-binding protein 4, which is related to the late differentiation of 3T3-L1 adipocytes. Taken together, these results suggest that Flavourzyme hydrolysates from farinfrared-dried red sea cucumber may be used as a functional food and/or a pharmaceutical ingredient for the inhibition of lipid accumulation.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.1
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• pp.45-50
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• 2017

Using the relatively low-cost, far-infrared dryer inhibiting the destruction of a variety of physiologically active components of the mulberry fruit, we have studied to make semidry mulberry fruit that can be kept at room temperature for a long time. By adjusting the temperature of the far-infrared dryer step-by-step, we developed a semi-dry method of maintaining the shape of the mulberry fruit. In addition, by drying the coating of honey after removing the juice generated by the mulberry fruit thawing process improved the acceptability of the taste of fruit. We conducted heat treatment mulberry fruit into a $95^{\circ}C$ infrared dryer 5 hours to thaw the frozen mulberry fruit. After 10 to 20% of honey coating, the primary drying ($95^{\circ}C$, 5 hours) was implemented. then, the secondary drying was conducted after controlling the temperature of the far infrared dryer $60^{\circ}C$, for 10 hours. These manufacture process was able to obtain semi-dried mulberry fruit. Dry weight ratio and moisture content were around 25%, and around 16% level respectively. It was to enable long-term storage at room temperature. Therefore, it is suggested that the method of using the far-infrared drying machine to manufacture semi-dried mulberry fruit can be a way to improve the farm income if applied to the farm.

• Journal of Biosystems Engineering
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• v.25 no.2
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• pp.115-122
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• 2000

This study was performed to develop a prototype continuous flow ginseng dryer with which better product quality and lower drying energy consumption could be achieved compared with conventional ginseng dryers. A dryer having both far infrared ray (IR) and heated-air as the drying energy sources was designed and fabricated . Dryer performance was studied by examining energy efficiencies and dryer performance evaluation indices (DPEI) during the drying tests of medium-sized four year ginseng roots with IR radiating plate temperature and drying air temperature in the range of 80-12$0^{\circ}C$ and 22-5$0^{\circ}C$, respectively. The DPEI of IR /heated -air combined drying was 1/3 of that of the conventional heated-air drying when ginseng were dried to the same final moisture ratio. When ginsengs were dried for 12 hours in the prototype IR/heated-air combination dryer, a linear relationship was found to exist between final moisture ratio and ginseng temperature. As the drying progressed, drying air temperature inside the dryer was nearly constant but ginseng temperature was drastically increased during the first two hours and gradually increased thereafter until the end of drying. With the prototype Ir/heated-air combination dryer, the drying rate changed little but the energy efficiency increased proportionally when the amount of ginseng to be dried increased. Drying capacity, energy efficiency, and DPEI of the prototype IR/heated-air combination ginseng dryer were estimated to 1.500 roots, 65% and 3.800kJ/kg-water , respectively.

• Korean journal of food and cookery science
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• v.16 no.1
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• pp.47-56
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• 2000

The purpose of this study was to develop a drying method of Gangjung. a traditional Korean snack, thus to reduce the drying time and to improve the quality of Gangjung. Two drying methods, hot air drying and far infrared ray drying were used by changing conditions such as air velocity(0.4, 1.2, 1.6 m/s), temperature(40, 50, 60$\^{C}$), and aging. Optimal moisture content of dried Gangjung pellet was 17% which was proper for frying. Cracks appeared on the surface of Gangjung pellet at lower levels of moisture content. Far infrared ray drying saved drying time about 20%. Both hot air drying and far infrared ray drying at 0.4 m/s of air velocity tended to show better quality of Gangjung than those dried at higher air velocities. The expansion volume and texture of Gangjung drying at 40$\^{C}$ was better than other temperature conditions, regardless of drying methods. Quality of Gangjung, dried at single stage without aging, was superior to those dried at double stage including aging process. Moreover, single stage drying save the drying time at least 24 hr. Gangjung dried at high temperature became hard and less brittle in sensory evaluation. In image analysis, air cell distribution in inner structure of Gangjung became uniform and fine as drying temperature decreased to 40$\^{C}$. Overall, Gangjung made of Gangjung pellet by the use of far infrared ray drying at 40$\^{C}$ without aging, showed the best quality in terms of physical and sensory properties.