• Journal of the Korean Wood Science and Technology
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• v.35 no.4
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• pp.45-51
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• 2007

To investigate the drying behaviors of the water-based natural coating made by rosin during drying, the mass transfer and optical change from speckle image and speckle rate were measured and the relationship between two analysis methods were investigated. At a linear scale, the speckle rate measured by HORUS related with the mass transfer of coating during drying, and the speckle rate at a log scale was included not only drying time, but also drying mechanism of coating during drying. Therefore, the HORUS was an available method to investigate the drying time and drying mechanism of coating during drying.

• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.635-641
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• 2006

In an attempt to find ways of improving the quality and sanitary state of dried squid, this study compared artificial drying methods i.e. hot air drying and cold air drying with natural drying method. The drying rates of squid were in the order of hot air, cold air and natural drying. However, cold-air drying was slower than natural drying at $7^{\circ}C$. The drying rates increased with increasing drying temperature. When drying temperature was close to the dew point on a dehumidifier surface, which was the case with cold air drying at $7^{\circ}C$, the driving force for dehumidification was lower than under other drying conditions, which resulted in a lower drying rate. There were little color differences between the drying methods and temperature. Squid dried by cold air-drying had better mechanical texture and sensory qualities than with other drying methods. In addition, the cold air drying method maintained superior quality in terms of the contents of amino acids, taurine, EPA, DHA, other fatty acids and a low TBA value than the other drying methods.

• Journal of Power System Engineering
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• v.15 no.4
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• pp.5-10
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• 2011

In case of using rapid vacuum-freeze drying for high quality dry flower of flowering plant, the morphological and physiological characteristics of dry rose showed as the following. The dry ratio of about 82% presented after 1 day in case of using rapid vacuum-freeze drying and it was reached that the optimum storage water content of general dry products was 18%. The dry ratio of about 89% presented after 4 days. This result indicates very short dry time comparing with natural dry time of 12 days. Also, the morphological characteristics of flowering plant in case of vacuum-freeze drying showed similar shape with real flower. The contraction decreased about 9% comparing with real flower under dry time of 72 hours. But the contraction in case of natural dry decreased 36% and showed noticeable difference. The brightness which affects physiological characteristics of dry flowering plant showed lower values according to the dry process and chromaticity was thick. After 4 days, natural dry was thick with about 2 times comparing with vacuum-freeze drying. In case of vacuum-freeze drying, the quantity of anthocyanin and chlorophyl which affect discoloration and bleaching of dry flowering plant showed the clear difference comparing with natural dry method due to the sublimation by vacuum after rapid freeze with short initial time.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.386-392
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• 1998

Experiments were carried out to establish an effective artificial drying method of Pacific saury (Cololabis seira) to kwamaegi. Raw fish containing 67% moisture were dried up to containing less than 40% moisture by drying for 15 days. The fish lost moisture more rapidly during first 3 days of natural drying than artificial drying. Total lipid content increased from 16.1% to 30.3 and 29.8% by 15 days of natural and artificial drying, respectively. Neutral lipid occupying 91.63% of total lipid increased to 92~94% during 15 days of drying, while content of phospholipid and glycolipid decreased slightly. The values of peroxide and thiobarbituric acid increased up to 6 days of drying and then did not change. Peroxide levels were lower in artifically dried fish than in naturally dried ones.

• Journal of Biosystems Engineering
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• v.4 no.2
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• pp.32-45
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• 1979

The major objective of this study was to develope a computer simulation model to analyze drying process in a deep bed with natural air. The approach used to describe the continuous drying process in a deep bed was to divide the process into many small processes and simulate them by consecutively calculating the changes of grain and air conditions that occurred during short increment of time. Success criterion of the drying system was based on grain deterioration estimated by drymatter decomposition during drying. The results of the experimental test showed that the model satisfactory.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.251-254
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• 2006

This study was conducted to identify changes of chemical components affected by different drying method and temperature conditions in leaves and stems of peony plant. Drying methods were the dried air heated $(50^{\circ}C)$, far-red ray $(50^{\circ}C)$, room temperature and oven dry $(50^{\circ}C)$. Drying temperature were 40, 50, 60, 70 and $80^{\circ}C$ on far-red ray dryer. Among the drying methods, the contents of components were the highest in far-red drying and normal temperature drying as compared with air heated drying and oven drying. Among the drying temperature conditions, the contents of components were the highest in drying temperature at $40^{\circ}C$ and decreased in high temperature of $70^{\circ}C\;and\;80^{\circ}C$.

• KSBB Journal
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• v.26 no.1
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• pp.49-56
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• 2011

Volatile components of crude fucoidan and its raw material, Undaria pinnatifida sporophylls were identified by GC/MSD analysis, and the effects of a combined method of solvent extraction and drying (hot-air drying or spray drying) on deordorization of fucoidans were examined. The major components of seaweed smell (odor) in crude fucoidan and Undaria pinnatifida sporophylls were identified as alkanes (octadecane, heptadecane, tetradecane) and acids (hexadecanoic acid, oleic acid). Solvent extraction and drying were combined for the deordorization of fucoidans: hot-air drying/deordorization process (HDDP) and spray drying/deordorization process (SDDP). The deordorization effects of solvent extraction using solvents including water, ethanol, and acetone were investigated. Among the tested solvents, ethanol was selected as a deordorization solvent, because the seaweed smell and taste were mostly lowered by ethanol extraction followed by drying. In addition, HDDP and SDDP were compared, showing that SDDP gave higher sensory characteristics than HDDP. When the crude fucoidan was treated by ethanol extraction for 30 min followed by SDDP, approximately 60% of off-flavor components of crude fucoidan was removed based on GC/MSD peak area, and the total sugar and sulfate contents and APTT-anticoagulant activity significantly increased compared to crude fucoidan. In conclusion, SDDP after ethanol treatment was proposed and established as a deordorization process for fucoidan preparation.

• Food Science and Preservation
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• v.11 no.2
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• pp.189-194
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• 2004

This experiment was carried out to compare the quality of semi-dried persimmon according to various drying methods and ripeness degree of persimmons. Most of persimmons were dried naturally there were much opportunities of contamination by impurities, microorganism and discoloration. There were need for developing various drying methods and knowing proper mature degree of persimmons in order to enhance the quality of semi-dried persimmons. Drying time of semi-dried persimmons by hot-air, far infrared ray and dehumid drying could be shorten approximately 11∼12 days, comparing with natural drying. And the loss ratio of natural drying and artifical drying were 7.0% and 0.0%. The moisture content of natural drying and dehumid drying were simillar and the hardness were very low in comparing other drying methods. Average pannel scores in semi-dried persimmons after drying showed that dehumid drying and natural drying were excellent in total prefernce ; 3.9 and 3.4, respectively. Unriped persimmons showed lower moisture content, color values and higher hardness than riped and overriped persimmons. The total preference of riped and overriped fruit were superior than unriped fruit.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.107-110
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• 1982

Fixed bed drying method was selected to reduce the initial drying time of squid and the effects of drying air temperature and bed height on the drying rate were investigated, with following results. 1. The drying rate in the fixed bed dryer was faster than that of natural convection type dryer heated indirectly and that of hot air dryer heated directly. 2, Shirai-equation was applicable to squid being dried. Using the equation, drying rate constant obtained was as shown in table 1.

• Journal of Environmental Science International
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• v.17 no.11
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• pp.1227-1233
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• 2008

The effect of freeze drying and fixatives in post-treating freeze drying on the morphological properties of the rose (Rosa hybrida L.) petal were investigated for the production of high quality of freeze dried rose. The morphology including form and color of the dried flowers of cut rose were depended on the drying methods. The drying time was extended due to their density and water content, and was shorter in the freeze drying than that in the natural and hot air drying. Freeze dried process for dried flowers took 2 days in a freeze dryer and did not cause shrinkage or toughening of rose petal being dried, preserving its natural shape and color. The diameter of freeze dried flowers showed little reduction compared to fresh flowers. In Hunter color values of petals of freeze dried flowers, L and a values were high and showed little variations in comparison to fresh petals. Freeze drying led to a noticeable increase in anthocyanin contents in petals, suggesting that anthocyanin contents play an important role in the acquisition of freezing tolerance. Exposure of flowers to freeze drying was accompanied by an increase in the carotenoid content. In the post-treating freeze drying, epoxy resin, a fixative, applied alone or in combination to petals of freeze dried flowers showed efficient coating for the protection from humidity and sunlight. Combined application of epoxy and acetone to freeze dried petals permitted maintenance of natural color and excellent tissue morphology, showing color stability and shiny texture in surface of petals. These findings suggest that application of fixatives to freeze dried rose petals improves the floral preservation and epoxy coating provides good quality in the freeze dried flower product.