• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.386-391
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• 2004

This study was performed to investigate change of quality characteristics on traditional dried Persimmons from Sangju varity regions (sun-dried, Namjang and Bokryong). Moisture contents on drying were decreased and constant at from 7th to 14th days drying periods and its periods were recognized to constructing second peel of dried persimmons. Constructed second peel were affected on quality characteristics of traditional dried Persimmons. Also, in case of semi-dried persimmons were processed at 45∼55% level of moisture content. Final products of semi -dried persimmons were estimated in 25th from initial drying periods. Changes of water activity were increased reducing speed at time of water content decreased, second feel constructing during drying persimmons were introduced to decreasing of water activity. Weights of dried Persimmons were quickly decreased in 21th drying periods and slowly decreased after that time. Weight changing and water evaporation of dried persimmons at the Namjang and Bokryong were slowy decreased and controled after 7∼14th in periods of constructing second feel of dried persimmons. Change of brix in dried persimmons have had in 18∼27% value at initial drying periods and quickly increased after 7∼14th in drying periods and have in high value of 40∼50% at 21th drying periods. At the texture of dried persimmons, hardness were decresed after 7∼14th in periods and effected on decreasing of water content, increasing of drying times. Sensory score of dried persimmons were highest score of color, sweetness and texture at dried persimmons of Namjang. Score of astringency, sourness and mold smell were highest at dried persimmons of Bokryong. Value of highest overall acceptance score was at dried Persimmons of Namjang.

• Journal of Conservation Science
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• v.27 no.1
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• pp.91-100
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• 2011

This study is to examine the PEG concentration, and drying humidity and drying periods of humidity-controlled drying(HCD) for conservation of waterlogged woods(Pinus densiflora S. et Z.), and dimension stability of HCD were compared with those of air-drying and vacuum freeze-drying(VFD). Dimension stability of vacuum freeze-drying was the most excellent, i.e., PEG crystal was uniformly distributed in woods. Increasing concentrations of PEG, dimension stability of HCD was increased and drying periods decreased. Dimension stability of HCD after the treatment with the high concentration(70%) of PEG soaking was similar to those of VFD after the treatment with the low concentration(40%) of PEG soaking. In conclusion, high concentration(about 70% in water) PEG solution was the most suitable as a pre-treatment for HCD of waterlogged woods. However, drying should be maintained with enough high humidity and longer period.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.203-211
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• 1989

During hot air drying of root vegetables such as radish and sweet potatoes, shrinkage and casehardening occurred, and thereby the quality change appeared. Therfore the hot air drying apparatus in which air temperature, relative humidity and air velocity could be controlled was designed, and the drying and shrinking characteristics of radish and sweet potatoes were studied. Also the external factors that affected these characteristics were investigated. The whole drying process of radish and sweet potatoes could be divided into four different drying rate periods, namely constant rate period, first falling rate period, second falling rate period (a) and (b). The shrinking rate curve consisted of four periods nearly corresponding to drying rate periods. The shrinking rate slowly increased in the constant rate period, rapidly increased in the first falling rate period, and reached the highest value in the early period of the second falling rate period. The surface shrinkage was greatly affected by the thickness of sample, relative humidity and initial moisture content. The shrinking ratio was increased with decreasing thickness and increasing relative humidity and initial moisture content.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.882-887
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• 1996

Some taste compounds such as nucleotide and their related compounds, trimethylamine oxide (TMAO), trimethylamine (TMA) and total creatinine of sea mussel and baby clam during drying at 40, 50 and 60^{\circ}C$ and storage at low temperature$(4^{\circ}C)$ and room temperature$(20^{\circ}C)$ were investigated. Six kinds of nucleotide and their related compounds such as adenine triphosphate (ATP), adenine diphosphate (ADP), adenine monophosphate (AMP), inosine, adenosine and hypoxanthine were analyzed. The contents od adenosine in raw sample was high in sea mussel and baby clam. The contents of ATP, ADP and AMP decreased, while those of inosine and hypoxanthine increased during drying and storage periods. The contents of TMAO, TMA and total creatinine were low in sea mussel and baby clam. TMAO and total creatinine decreased but TMA increased during drying and storage periods. The rate of change was high in room temperature storage and for long storage periods than that of low temperature storage and for short storage periods.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.405-412
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• 2000

A natural air in-bin grain dryer with a grain circulator was developed for on farm use. Natural air drying test for rough rice was carried out to evaluate drying rate, uniformity of moisture content distribution in grain bed and energy consumption. It took 10 days to dry 8 ton of paddy rice from 21.9%(w.b) to 16.7%(w.b) moisture contents using the prototype dryer. The average drying rate was 0.52%/day. The uniformity of moisture content after drying was superior to the conventional natural air dryer where is grains were not circulated during drying periods. The dryer performance evaluation index was 738.3KJ/(kg.water), which was more effective than that of grain circulation t)pe hot air dryer(3,500-5,000 KJ/kg.water).

• Journal of environmental and Sanitary engineering
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• v.13 no.1
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• pp.9-15
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• 1998

Microwave heating and drying processes have been well established in various industrial applications. Feasibilities of successful application of microwave drying to many material have been shown on the laboratory or pilot-plant scale. The microwave drying behavior of plating sludge are considered in this paper. The plating sludge containing 70%, 80% and 90% water exposed to microwave power at 2,450 MHz, 700W. An experimental microwave drying apparatus was designed and constructed to monitor weight loss during drying. By studying the drying characteristic curve, the moisture in sludge was almost classified into two categories : free moisture and intestinal moisture. And the critical moisture contents at which the drying rate ceases to be constant were from 10.1 to 10.5%. A simple drying model is proposed which may be used to describe drying behavior of plating sludge. The constant rate and the falling rate periods in microwave drying were addressed separately. From the eqation of constant rate period the drying rate constants decreased exponentially with increasing depth. Microwave heating compared with conventional heating offered higher heating rates from 9 to 16 times. Therefore, microwave drying process can be effective in removing moisture from plating sludge.

• Journal of Animal Science and Technology
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• v.54 no.1
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• pp.35-41
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• 2012

The aim of this study was to offer information about appropriate processing method for dry cured-ham with controlled ripening condition. In this study, three different treatments were performed: High salt group (HS), 18 hams were salted with 70 g $kg^{-1}$ salt (w/w) Middle salt group (MS), 18 hams were salted with 50 g $kg^{-1}$ salt Low salt group (LS), 18 hams were salted with 30 g $kg^{-1}$ salt. Also three drying periods were applied (180 days, 270 days and 360 days). The weight loss in HS was higher (5.62%) on curing step and in LS was higher (12.35%) on post-salting step compared to other groups. On fermentation stage, weight loss of HS was higher than that of LS (p<0.05). Weight loss on drying was increased as the drying period passes (p<0.05). Moisture contents were significantly (p<0.05) decreased and fat contents were significantly (p<0.05) increased in all treatment groups as drying period increased. The different drying periods affected fatty acid compositions on all salting levels; saturated fatty acid contents were increased (p<0.05) with more drying, whereas unsaturated fatty acid contents were decreased (p<0.05) as drying period increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.774-778
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• 1996

The changes in organic acid contents of sea mussel and baby clam during drying at 40, 50 and $60^{\circ}C$ and storage at low $temperature(4^{\circ}C)$ and room $temperature(20^{\circ}C)$ were investigated. Organic acids of 8 varieties were determined and the content of succinic acid occupied over 90% of total organic acids in sea mussel(410.9mg%) and baby clam(96.5mg%). Malic acid was in order in sea mussel(41.2mg%) and lactic acid was in order in baby clam(61.9mg%). The content of organic acids was decreased during drying and rate of decreasing was higher at low drying temperature(40 and $50^{\circ}C)$ than that of high drying $temperature(60^{\circ}C).$ The decreasing rate was higher at room $temperature(20^{\circ}C)$ storage and long storage periods than that of low $temperature(4^{\circ}C)$ storage and short storage periods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.768-773
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• 1996

The changes in amino acid contents of sea mussel and baby clam during drying at 40, 50 and 6$0^{\circ}C$ and storage at low temperature(4$^{\circ}C$) and room temperature(2$0^{\circ}C$) were investigated. Amino acids of 17kinds were analyzed in sea mussel and baby clam. Total amino acids content of raw sample were similar to sea mussel and baby clam(6575.30mg%, 6764mg%), decreased during drying and rate of decreasing was higher in baby clam than that of sea mussel. The content of Glx was highest in sea mussel(790.55mg%) and baby clam(990.89mg%), other amino acids differed from samples. The content of amino acids of low drying temperature(40 and 5$0^{\circ}C$) decreased was higher than that of high drying temperature(6$0^{\circ}C$). The rate of decreasing was higher at room temperature(2$0^{\circ}C$) storage and short storage periods than that of low temperature(4$^{\circ}C$) storage and long storage periods.

• Journal of Biosystems Engineering
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• v.25 no.3
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• pp.227-232
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• 2000

A natural air in-bin grain dryer with a grain circulator was developed for on farm use. Natural air drying test for rough rice was carried out to evaluate drying rate, uniformity of moisture content distribution in grain bed and energy consumption. It took 10 days to dry 8 ton of paddy rice from 21.9%(w.b) of moisture contents to 16.7%(w.b), by prototype dryer and the average drying rate was 0.52%/day. The uniformity of moisture content after drying was superior to a conventional natural air dryer in which grains were not mixed during drying periods. The dryer performance evaluation index was 738.3kJ/(kg.water), which was more effective than that of grain circulation type hot air dryer(3,500∼5,000 kJ/kg.water)