• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.2
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• pp.127-132
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• 2004

In industrially advanced countries, environmentally conscious machining was eagerly studied because of ecological and economical reasons. As the environmental regulations become stricter, the new machining technologies which take environmental aspects into consideration are being developed. Recently the research institutions have established application method for dry, semi-dry, oil-mist and compressed cold air machining. In this paper the performance of new compressed cold air system for environmentally conscious machining is investigated and machinability of dry and new compressed cold air machining is evaluated. A series of tests are carried out by using measuring equipments in condition of dry and compressed cold air machining.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.6
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• pp.987-995
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• 2009

The effects of Kwamaegi on serum lipid profiles and ROS(reactive oxygen spices) generating and scavenging enzyme activities were investigated in rats. The three experimental groups were divided as follows: normal control diet group (NC), 5% naturally prepared and freeze-dried Kwamaegi supplemented diet group (NPK) and 5% chitosan-ascorbate treated and artificially dried (CWDD: Chilly Wind & Dehumidification Drier) Kwamaegi supplemented diets group (CAK). There were no significant differences in weight gain, feed intake, feed efficiency ratio or organs weights per body weight including liver, kidney, heart and spleen among the group. In addition, there were no significant differences in serum triglyceride and total cholesterol contents. The HDL-cholesterol contents of the NC, CAK and NPK groups were 62.00, 36.48 and 78.44 mg/dL while LDL-cholesterol contents were 62.00, 36.48 and 78.44 mg/dL, respectively, which were significantly different. The atherogenic indeces in the experimental groups were 0.62, 1.20 and 0.13, respectively. There were no significant differences in total XOD (xanthine oxidoreductase) activities; however XOD type O activity was higher in the NPK group than un the NC group and in the CAK group XOD type O activity was 21~45% lower compared to NC and NPK groups. SOD (superoxide dismutase) activity was significantly higher in the CAK group than in the NC and NPK groups, while there were no significantly differences in GST (glutathione S-transferrase) activity among the groups. Furthermore, serum ALT activity was higher in the NPK group versus the NC and CAK groups. GSH (glutathione) content was higher and LPO (lipid peroxide) content lower in the CAK group compared to the NC and NPK groups. Forem the above results, we suggest that CA treated and artificially dried Kwamaegi is not only a hygienic product but also has lowering effects on LDL-cholesterol and the atherogenic index together with the lowering of ROS-generating and increasing of ROS-scavenging enzyme activities compared to other natural products.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.4
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• pp.526-534
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• 2011

Cold air drying was conducted on steamed chestnut-sweet potato to improve its quality, convenience, and preference as snack. Steamed sweet potato was dried from 10 to $25^{\circ}C$ for 48 hours, and moisture contents, colors, texture, and taste were evaluated. The lowest moisture content was 4.53% at $25^{\circ}C$. Lightness decreased while other color values (a, b, and ${\Delta}$E) increased with increasing drying temperature and drying time. Reducing sugar and soluble solid contents ranged from 93.22~190.35 mg/g and 17~60 $^{\circ}Brix$, respectively. The highest hardness of chestnut-sweet potato was 25.13 kgf/$cm^2$, and springiness and cohesiveness were 88.60, and 94.87%, respectively, when dried at $25^{\circ}C$ for 48 hours. Sensory evaluation score was highest at $20^{\circ}C$ for 24 hours. The optimum drying conditions were determined to be $19^{\circ}C$ and 39.5 hours by RSM(response surface methodology).

• Journal of Food Hygiene and Safety
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• v.30 no.1
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• pp.74-80
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• 2015

In this study, the microbial control effect after treatment of washing solutions (tap water, electrolyzed water, chlorine dioxide solution) and quality changes were investigated when Kwamegi is produced by means of the cold air drying. The initial moisture rate of the sample was 56.62% before drying. At the beginning of drying period, moisture rate sharply fell down but as the experiment progressed, moisture reducing rate was smoothly decreased. The color difference of Kwamegi before drying was 42.40, but it was reduced depending on the increment of drying temperature and time. TBA value of the initial sample was 0.219, rancidity were increased continuously when drying progressed. Total amino acid content was showed the highest value at $25^{\circ}C$ for 36h and the lowest at $40^{\circ}C$ for 12h. From the fatty acids analysis, major fatty acids were consisted of the 14:0, 16:0 and 18:1 (18.1520.96%, 28.0632.51% and 17.0619.81%, respectively). The microbial control effect was biggest when Kwamegi was washed with chlorine dioxide 100ppm for 60s. The microbe of the Kwamegi, Pseudomonas sp. and Pseudomonas putida were identified.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.3
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• pp.425-433
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• 2015

This study investigated changes in physicochemical characteristics by drying and fermentation in order to utilize Actinidia arguta. Moisture content of A. arguta was 85.81%. Major sugar and organic acids were sucrose, succinic acid, and citric acid. A. arguta contained 19 kinds of amino acids, including 8 kinds of essential amino acids such as valine, methionine, isoleucine, leucine, threonine, phenylalanine, tryptophan, and lysine. For total organic acids, sample fermented for 17 h at $50^{\circ}C$ under a relative humidity of 80% showed 29,026.53 mg/100 g total organic acids. For total free sugars, cold-dried sample showed the highest level at 6,560.86 mg/100 g, which decreased to 2,386.73 mg/100 g after blanching. For the ratio of essential amino acids, freeze-dried sample showed a content of 11.66%, which increased 4-fold up to 40.71~55.50% with fermentation. Both GABA and vitamin U were highest after 17 h of fermentation (110.29 mg and 6.78 mg/100 g fresh weight, respectively). A. arguta contains a variety of free amino acids that increase in amount after fermentation and thus is expected to be developed as a functional food and substitute tea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.spc1
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• pp.104-107
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• 2005

This survey was conducted to know the post-harvest bulk treatment system for barley, The tendency of barley-bulk treatment in 4 RPC was gradually increased up to 4,458 ton in 2001, but after that time, the amounts was decreased 1,0731on in 2003. There was the big difference on the circulated and the continued systems that was the kinds of drying system they use. The barleys, the harvest and the conveyance method was different on RPCs. Naked barley was only treated, and $90\%$ barley was harvested by the consignment in J RPC, otherwise unhulled barley was treated, and there did not used the consignment in S RPC. Small and mulit combine was used to harvest, and the ratio of bulk was up to $90\%$ in J RPC, but small combine was only used and ratio of bulk was at most $5\%$ in S RPC. It was sell by 1kg in polished and 40kg unpolished barley around year in J RPC, but it was sell by bulk to september in S RPC.

• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.466-472
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• 2013

This study was performed to determine the effects of the pretreatment and cold-vacuum drying methods on the physicochemical properties and antioxidant activities of dried peaches. Moisture content was significantly lower with 0.3% NaCl treatment with cold-vacuum drying. The pH, brix and acid ratio (SS/TA) were the lowest with 1.0% soluble Ca treatment, while soluble solid and SS/TA were significantly higher with 0.1% vitamin C treatment compared to those with other treatments. The ${\delta}E$ and browning degree was lower in the pretreated sample compared to the untreated sample. Cutting strength of dried peaches was highest in the pretreated samples, and it was the highest with 1.0% soluble Ca treatment. Total sugar content with 0.1% vitamin C and 1.0% soluble Ca treatment was significantly higher than that with 0.3% NaCl treatment. The free sugar content was lower with 0.3% NaCl treatment but it was higher with 0.1% vitamin C and 1.0% soluble Ca treatment. The sensory evaluation result was highest with 0.1% vitamin C treatment. Phenolic compounds and antioxidant ability were the highest with the 0.1% vitamin C and 0.1% soluble Ca treatment; all the dried peaches showed relatively high antioxidant activities. These results suggest that pretreatment can affect the quality of dried peaches, showing that cold-vacuum drying can be applied for the production of high quality dried peach products.

• Food Science and Preservation
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• v.18 no.4
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• pp.488-496
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• 2011

Cold-air drying was conducted for a steamed pumpkin-sweet potato slab to improve its quality, convenience, and preference as a snack. A steamed pumpkin-sweet potato slab was dried from 10 to $25^{\circ}C$ for 48 h, and its moisture content, color, texture, and taste at different drying temperatures and drying times were evaluated. The lowest moisture content was 4.98%, at $25^{\circ}C$. The lightness decreased, but the other color values (a, b, and ${\Delta}E$) increased with the increasing drying temperature and drying time. The reducing sugar and soluble solid ranged from 98.7 to 194.75 mg/g and 19-70 $^{\circ}Brix$, respectively. The highest hardness of the steamed pumpkin-sweet potato slab was 23.88 $kg_f/cm^2$, and the springiness and cohesiveness were 91.15 and 98.36% when it was dried at $25^{\circ}C$ for 48 h. The sensory evaluation score was high at $10^{\circ}C$, 40 h and at $25^{\circ}C$, 24 h. The optimum drying condition was predicted at $19^{\circ}C$, 32 h via response surface methodology (RSM).

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.968-973
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• 2003

As environmental restrictions have continuously become more strict, it has emphasized development of environment-friendly technologies. In cutting technology, it has been well recognized that cutting fluids might have undesirable effects on worker's health and working environment and, hence, recently there have been numerous attempts to minimize harmful effects of cutting fluids on environments. To minimize the use of cutting fluids in machining, conventional cutting fluids have been replaced with the technologies of pressurized cold air and minimum quantity lubrication(MQL). Compared with milling, turning is a continuous cutting process, where tools are continuously heated up and lack of lubricity could lead to tool wear and deteriorated surface roughness. In this study, it has been investigated how tool wear and surface roughness could be affected by cutting conditions, supply and cooling methods. The experimental results show that MQL technology is able to minimize harmful effects of conventional cutting fluids.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.6
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• pp.1007-1013
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• 2003

As environmental restriction kas continuously become more strict, machining technology has emphasized on development of environment-friendly technology. In cutting technology, it has been well recognized that cutting fluids might have undesirable effects on workers health and working environment. In this study, compressed cold air was used as a replacement for conventional cutting fluids. The cooling effect on cutting tool was analyzed using the finite element method and the computational fluid dynamics. This study focused on the temperature simulation of cutting tool by real flow analysis of cold air. The maximum flow rate and the minimum temperature of compressed cold air are 300ι/min and -30$^{\circ}C$ respectively. To compare the simulation and experimental results, inner temperature of the cutting tool was measured with the thermocouple embedded in the insert. The results show that the analysis of cutting temperature using FEM and CFD is resonable, and the replacement of cutting fluid with cold air is available.