• Journal of Ginseng Research
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• v.33 no.4
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• pp.361-366
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• 2009

This research aims to develop a new drying technology using super-heated steam to reduce the time required for drying ginseng and to enhance its quality. The drying rate of ginseng powder treated with hot-air drying after drying with super-heated steam was about 40% faster than the drying rate of ginseng powder treated with hot-air drying. Minimal difference was found between hot-air drying and hot-air drying after drying with super-heated steam in the general composition of the ginseng powder, such as its crude lipid, crude protein, crude fiber, and ash. Moreover, no difference was found between hot-air drying and hot-air drying after drying with super-heated steam in terms of the ginseng powder's mineral and free sugar contents. The crude saponin contents was 5.43% in the ginseng treated with hot-air drying and 5.4% in the ginseng treated with hot-air drying after drying with super-heated steam. The ginseng powder that was treated with hot-air drying after drying with super-heated steam had a slightly higher redness compared to the ginseng powder that was treated with hot-air drying alone. The number of microorganisms of the ginseng powder treated with hotair drying after drying with super-heated steam showed a reduction of one log cycle in the total bacteria and two log cycles in the yeast molds compared to the ginseng powder treated with hot-air drying alone.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.721-725
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• 2008

Changes in the physicochemical and sensory characteristics of the uncooked food, Codonopsis lanceolata saengsik, were investigated to determine an efficient drying method, one of the most important manufacturing processes in the preparation of C. lanceolata saengsik. No changes in the proximate compositions of all samples were observed during hot-air drying at 50 and $60^{\circ}C$ and freeze-drying. The L value in the freeze-dried sample was higher than that in the hot-air dried samples, whereas the b value in the freeze-dried sample was reduced. Dietary fiber content in the hotair dried samples were higher than that in the freeze-dried sample, whereas the total phenolic compounds and crude saponin contents were lower than those in the freeze-dried sample. The highest overall acceptability values in the sensory test for color, flavor, taste, and overall acceptability were 5.63, 5.45, 5.75, and 5.85, respectively. In conclusion, the freezedrying method was the most favorable of the tested method for the manufacture of C. lanceolata saengsik.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.973-980
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• 2000

This study was conducted to evaluate the quality of the cold air dried anchovies (CA), and compared with those of sun-dried anchovies (SA) and hot air dried anchovies (HA). Peroxide value increased, while ratio of percentage of (20:5+22:6) to that of 16:0 decreased during boiling and drying. The extents of change were CA>SA>HA in the order. In the case of CA, lightness was higher, but redness, yellowness and degree of browning was lower than in SA and HA. From the results of lipid properties, color test and sensory evaluation on color and rancidity odor, lipid deterioration was the lowest in CA of all boiled dried anchovy. Favorite properties such as a hot-water soluble nitrogen content and sensory evaluation on color and appearance of CA was superior to that of SA and HA. The nutritional properties (total amino acid contents, mineral contents and fatty acid compositions) of CA was similar to that of SA, but was superior to that of HA. Consequently, CA was recognized as a boiled dried anchovy with the most quality.

• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.506-512
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• 2006

We investigated changes in the physicochemical characteristics and functional components of the Saengsik cereal grains-milled rice, brown rice, glutinous rice, and barley- by washing with electrolyzed water. There were no changes in the composition of all cereal grains that was dried with hot-air and freeze-dried after being washed with electrolyzed water. The L and a values were not affected by drying in milled rice, brown rice, glutinous rice, or barley, but the b value increased in milled rice and glutinous rice-this increase was greater with hot-air drying than with freeze-drying. The dietary fiber content of the all cereals increased with hot-air drying. The niacin content decreased in all cereals; the extent of this change was greater with hot-air drying than with freeze-drying. The ${\beta}-glucan$ content of barley was higher in samples that underwent freeze-drying than in those treated by hot-air drying, but was not affected by washing with electrolyzed water. Thus, other than a change in color for milled and glutinous rice, no changes in the physicochemical characteristics and functional components these products were observed with freeze-drying. Data indicate that the electrolyzed water washing could be effectively used as pasteurization step in the uncooked cereal grains.

• Journal of the Korean Wood Science and Technology
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• v.32 no.1
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• pp.45-51
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• 2004

Combined microwave-convective drying of 2.4mm-thick radiata pine veneer grown in New Zealand was conducted to investigate drying characteristics. The veneers could be dried from 160% to 0% moisture content in 7.5 min by microwave drying combined with hot-air of 100℃. This drying rate is about three times higher than that of conventional convective drying with only hot air of 100℃. However there remained charred spots when too high microwave power was applied. Therefore investigations of the microwave-drying characteristics of veneer of various sizes and species are needed to determine the optimal drying conditions.

• Culinary science and hospitality research
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• v.19 no.4
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• pp.13-24
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• 2013

This research intends to examine the quality characteristics of madeleines after adding drying frozen mulberries by freeze drying and hot-air drying, making them powdered. The general ingredients and physiochemical characteristics of each specimen were measured, compared and analyzed. Madeleines were made based on the recipe set in practical examination of bakery technicians, in which each specimen is added with 0%(control), 1%, 3%, 5%, 7% of mulberry powder depending on the quantity of flour. And then, pH, chromaticity and texture were measured and consumer preferences were grasped by sensory testing. The test results are as follows. First of all, pH was low in the group added with hot-air drying mulberry powder. In chromaticity, brightness(L value) was reduced in comparison with the control group as the addition rates of freeze-drying mulberry powder and hot-air drying mulberry powder increased. Red chromaticity(a value) increased more when adding hot-air drying mulberry powder rather than freeze-drying mulberry powder. Yellow chromaticity(b value) was reduced as addition of mulberry powder increased. Hardness and elasticity of the group added with freeze-drying mulberry powder showed significant differences as addition of mulberry powder increased. Cohesiveness and gumminess was reduced as the addition increased. Hardness of madeleines added with hot-air drying mulberry powder showed significant differences by addition rates of mulberry powder. Elasticity increased by the quantity of mulberry addition. Cohesiveness was reduced as the addition was reduced. Gummines increased as the addition increased. As the result of sensory test on preference, the preferences of the group added with 5% of freeze-drying mulberry powder and the group added with 7% of hot-air drying mulberry powder were the highest.

• Food Science and Preservation
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• v.23 no.5
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• pp.689-695
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• 2016

In this study, the drying characteristics of medicinal (Ganoderma lucidum, Phellinus linteus) and edible (Pleurotus eryngii, Lentinus edodes) mushrooms were investigated. Their shrinkage ratios, Hunter's color values, and rehydration ratios were evaluated. Mushrooms were cut with rectangular (1 cm) and square ($1{\times}1cm$) shapes, and dried in the room temperature and at $50^{\circ}C$ and $70^{\circ}C$ using hot-air dryer. Initial moisture contents of edible mushrooms were higher than those of medicinal mushrooms, whereas final moisture contents were vice versa. Drying rate was the highest when drying at $70^{\circ}C$ (p<0.05). Moreover the drying rate of square slices was higher than that of rectangular slices (p<0.05). The shrinkage ratios of both medicinal mushrooms and edible mushrooms were the least when drying at $50^{\circ}C$ and $70^{\circ}C$, respectively (p<0.05). The changes of color values were less in the medicinal mushrooms dried in the room temperature than in the hot-air dried medicinal mushrooms (p<0.05). However, in case of edible mushrooms, the changes of color values were less in the hot-air dried mushrooms (p<0.05). Rehydration ratios of medicinal mushrooms dried at $50^{\circ}C$ was the highest (p<0.05). In contrast, rehydration ratios of edible mushrooms was the highest when drying in the room temperature (p<0.05). Thus, the hot-air drying at $50^{\circ}C$ would be suggested as the efficient drying method for both medicinal mushrooms and edible mushrooms.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.188-196
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• 2006

Changes in physicochemical characteristics and functional components content of saengsik, uncooked food, were investigated to find efficient drying methods, one of important manufacturing process of saengsik. No changes in proximate compositions of all samples were observed during hot-air drying at 50, 55, and $60^{\circ}C$ and freeze-drying. Colors of carrot, Lentinus edodes, and sea mustard did not change, while a value of cabbage, L, a, and b values of Agaricus bisporos, and a value of laver changed slightly by hot-air drying at all temperatures and freeze-drying. Dietary fiber content increased by hot-air drying but not by freeze-drying. Reductions in vitamin C and ${\beta}-carotene$ contents of carrot, cabbage, sea mustard, and laver were higher by hot-air drying than by freeze-drying. Contents of total phenolics and lectin of L. edodes and A. bisporos were not affected by hot-air drying and freeze-drying. Contents of pectin, alginic acid, and porphyran in sea mustard and laver increased by hot-air drying.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1680-1687
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• 2011

This study was performed to determine the effects of pretreatment and drying methods on the quality and physiological activities of garlic powders. Fresh garlic was boiled, baked, steamed or left untreated before hot-air drying or freeze-drying. Electron-donating abilities were higher in the untreated group for each drying method. Relative EDA of baked group was 32.8%, whereas those of the boiling and steaming groups were 12.4% and 20.1%, respectively. Nitrite-scavenging effects were slightly affected by processing methods. Polyphenol content of the processing group was higher in the hot-air drying than freeze-drying group, and it was significantly highest in the untreated freeze-dried group. The value of polyphenol in the baked group was significantly higher than those of the boiling and steaming groups. Tyrosine contents of garlic powder were higher in the hot-air drying than freeze-drying group, and it was significantly highest in the untreated group of each drying method. Antimicrobial activities of the garlic powders were higher in freeze-drying group compared to the hot-air drying group. Therefore, antimicrobial activities of garlic powder were affected by heating treatments.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.877-882
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• 1998

To establish optimum drying methods for Korean yam, freeze drying, cool air drying and hot air drying methods were compared by determining some quality criteria. The native color, odor, taste and viscosity of raw yam were preserved by only freeze drying at less than $40^{\circ}C$. The native white color of yam changed to brown and odor and taste of yam decreased largely by cool air drying and hot air drying. Especially cooked and roasted flavor was developed in hot air dried yam. The viscosity of cool and hot air dried yam was about half than that of freeze dried yam. Conclusively freeze drying method was shown optimum to preserve quality properties of yam such as viscosity, color, odor and taste. The physical properties of yam powder such as dispersiveness and solubility was the best in $40{\sim}60{\;}mesh$ particle size.