• Food Science and Preservation
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• v.14 no.6
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• pp.591-597
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• 2007

The quality characteristics of semi-dry red pepper (SDRP) (Capsicum annuum L.) were compared with raw and dry red pepper (DRP). Raw red pepper was divided into pieces and the semi-drying treatment involved air-drying at $65^{\circ}C$. The study focused on describing the characteristics of semi-dry red pepper in comparison with dry red pepper. Factors considered were reduced drying period, ASTA color, capsanthin, capsaicinoids, free sugars and vitamin C content. ASTA color, capsanthin, capsaicinoids, free sugars and vitamin C content of SDRP were higher in SDRP than in DRP for 15 g or less water per 100 g. Red pepper powders made using the semi-drying method showed the highest amount of glucose and vitamin C. Capsanthin content in SDRP (151.6155.9 mg/100 g) was significantly higher than for DRP (133.4 mg/100 g). The capsaicinoid content of SDRP was about 13-25% higher than in DRP. The ASTA values (148.7159.3) for SDRP were much higher than for DRP (139.5). The vitamin C and free sugar content of SDRP was 40-76% and 20-40% higher, respectively, than for DRP. and $20{\sim}40%$, respectively, by SDRP compared to DRP.

• Food Science and Preservation
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• v.12 no.1
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• pp.54-61
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• 2005

The absorption characteristics and their physical properties of hot air, vacuum and freeze dried soybean curd powder were investigated. Absorption conditions were at 5, 15, and 25 t with $0.11\~0.93$ water activities. Equilibrium moisture content and the monolayer moisture content determined by prediction models showed highest value in the freeze dried soybean curd powder due to porous structure. Absorption energy decreased with increasing water activity was not affected by drying method. In the comparisons of the isothermal absorption models, Oswin model generally was the best fit model for isothermal adsorption of soybean curd powder.

• Journal of the Korean Society of Food Science and Nutrition
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• v.7 no.1
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• pp.1-6
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• 1978

Muscle fillets of flounder, Limanda herzensteini, were sliced into small pieces and dehydrated by the methods of sun drying, hot air drying and vacuum freeze drying, and evaluated for the protein quality by the method of shortened pepsin pancreatin digest residue (SPPDR) index which is the modified method of shortened pepsin digest residue index. In the analysis of the muscle protein hydrolysates, glutamic acid, aspartic acid and lysine comprised about 39% of the total amino acids of the protein. The content of pure protein in flounder muscle was 18.8%. The result of nutritional evaluation of the dried muscle protein by the computation of the SPPDR index showed that the freeze dried flounder muscle protein was superior in the nutritional efficiency to the others, sun dried. The freeze dried flounder muscle protein marked 89 of the SPPDR index number which is quite similar to the muscle protein of terrestrial animal in nutritional quality.

• Journal of the Korean Ceramic Society
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• v.18 no.2
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• pp.83-90
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• 1981

In this study, the effect of additions on magnetic properties in the system of [$Ni_{0.32}Zn_{0.68}$] 1-x Mx $Fe_2O_4$ have been investigated. The additions, Co or Mg or Cu, was added in turn in place of M, and its composition was varied from 0.1 mo1% to 0.5 mo1%. The materials were blended by hot petroleum drying method, and sintered with the rate of 30$0^{\circ}C$/h in the air. The sintering temperatures were varied from 110$0^{\circ}C$ to 130$0^{\circ}C$, with the intervals of 5$0^{\circ}C$, and matured for 3hrs. The results are: 1) The permeability decreased when the addition, MgO or CoO, was added, and it increased when CuO was added. 2) Resistivity had the lowest Value when CuO was added.

• Journal of Power System Engineering
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• v.10 no.2
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• pp.36-40
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• 2006

In order to prevent the environmental pollution, the dryers are commonly used to treat sludge that one of sewages is polluting the quality of water. Generally, the drying method is various as to the property of material and use. Rotary dryer is a good apparatus to treat them. It is the way that is to make substance transmission and heat using hot air between sludge particle and heated gas. In this paper, we developed a 3-pass rotary dryer for a design program for the 3-pass rotary dryer with various conditions. The working conditions of dryer are a raw sludge feed rate, input & output water content and operation time etc.

• Korean Journal of Food Science and Technology
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• v.51 no.1
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• pp.29-34
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• 2019

In this study, a commercial production stepwise method for restorative rice with high quality and microbial safety was developed. The stepwise treatment method included steaming, refrigerated aging, and low temperature drying. The soaking rice was steamed twice at $90-100^{\circ}C$, and then, the rice was aged at $0-10^{\circ}C$, frozen at $-20^{\circ}C$, and dried at low temperatures with 5 m/s wind speed at $1-20^{\circ}C$ and 85% relative humidity. Applying the three steps improved sensory qualities compared with the conventional hot air drying and made storage at room temperature for 3 months possible. Specifically, the moisture content of the restorative rice was increased to 30%, which was 4.3 times higher than the 7% of the conventional air dried rice, and the rice grain shape was well maintained. The texture and appearance of the three-step rice were significantly improved (p<0.05) in a sensory evaluation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.5
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• pp.753-758
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• 1997

Dried alaska pollack is one of the representatives among dried marine fish and shellfish products in our country. This study was performed to obtain the basic data about the effect of drying method on the formation of N-nitrosamine and its precursor to ensure the safety of dried alaska pollack. The contents of nitrate and nitrite were detected 1.5 and <1.0 mg/kg in raw samples, and $3.0\~4.2,\;1.4\~2.7mg/kg$ in dried products, respectively. There was no significant change of betaine contents during drying while TMAO decreased, TMA and DMA increased in alaska pollack during d교ing. N-nitrosodimethylamine (NDMA) was only detected in alaska pollack and its dried products, and recovery from above samples spiked with $10{\mu}/kg$ for N-nitrosodipropylamine was $87.2\~107.4\%$. The levels of NDMA were found to be $2.8{\mu}/kg$ on an average in raw samples, but the levels of NDMA increased remarkably during drying of alaska pollack and its content in dried products was $8.7\~51.4{\mu}g/kg$. Regardless of drying methods, NDMA tend to increased in dried products, and its contents were 15.5 times higher in hot-air dried than raw samples, 9.0 times in sun dried and 4.4 times in freeze dried products. less NDMA was produced in the freeze dried products, so it is believed that freeze drying method is effective to decrease the NDMA levels in the dried products of alaska pollack.

• Food Science and Preservation
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• v.23 no.1
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• pp.1-6
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• 2016

The physiological activities of 70% ethanol extracts of grape seed (GS) prepared by freeze-drying (GSFD), infrared drying (GSIR), hot-air drying (GSHD), or sun-drying (GSSD) were investigated. The moisture contents of GSFD, GSIR, GSHD and GSSD powders were 4.53, 6.71, 6.91 and 5.55% respectively. Hunter's color value analysis revealed that the $L^*$ value of GSIR was lower, and the $a^*$ and $b^*$ values of GSIR were higher, than those of GSFD, GSHD, and GSSD. The total polyphenol and proanthocyanidin contents of GSFD were significantly higher than those of the other extracts. The flavonoid related substance contents were in the order of GSFD (7.68 g/100g) = GSSD (7.59 g/100g) = GSHD (7.33 g/100g) > GSIR (6.45 g/100g). The electron donating abilities of $500{\mu}g/mL$ solutions of GSFD, GSIR, GSHD and GSSD were 88.71, 52.62, 65.20, and 65.22%, respectively, while their reducing powers ($OD_{700}$) were 1.633, 1.097, 1.217 and 1.054 absorbance units, respectively. Additionally, the same trend was observed for the ABTS radical-scavenging abilities of the extracts as that observed for their electron-donating abilities and reducing powers. These results suggest that GSFD is the best method for preparing GS extracts with enhanced antioxidant activities, and that GS extracts may be used as a natural antioxidant material for use in health foods.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.468-474
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• 1993

A dehydrating sheet comprises polymeric water absorber. which are packed in a semipermeable cellophane film bag allowing selective permeation of water. This sheet dehydration is quite different from conventional drying method such as sun drying, hot-air blast drying and cold air blast drying in a sense that samples are dried without heat treatment. As a part of the studies to develope a new processing method for effective utilization of dark muscle fishes, the preparation of a good quality salted and semi-dried mackerel by the dehydrating sheet was attempted. The dehydration time for preparation of a salted and semi-dried mackerels containing approximately equal moisture content were revealed $180{\sim}510min$ in conventional drying method and $90{\sim}160min$ in this sheet dehydration, respectively. The moisture and histamine contents of those salted and semi-dried mackerels were $59.4{\sim}62.4%$ and $2.5{\sim}3.6 mg/100g$, respectively. The changes in peroxide value, fatty acid composition, brown pigment formation, myofibrillar protein solubility and Ca-ATPase activity during processing of the salted and semi-dried mackerel prepared by the sheet dehydration were more lower than those of products prepared by conventional drying methods. Therefore, these result showed that the quality of a salted and semi-dried mackerel prepared by the sheet dehydration was imperial to that of those products by conventional drying method.

• Journal of Power System Engineering
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• v.9 no.4
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• pp.51-57
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• 2005

In order to prevent the environmental pollution, the dryers are commonly used to treat sludge that one of sewages is polluting the quality of water. Generally, the drying method is various as to the property of material and use. Rotary dryer is a good apparatus to treat them. The rotary dryer is the way that is to make substance transmission and heating using hot air between sludge particles and heated gas. In this paper, we performed a numerical analysis of the inner air flow of the 3-pass rotary dryer through the changing rotational speed from 3rpm to 10rpm. In this result, we found that 3rpm is effective to dry material in terms of heat transfer because large scale velocity fluctuation is occurred inside the first and second drum. Also we confirmed that 5rpm and 8rpm showed up uniform flow at the center area of the first drum.