• Journal of Biosystems Engineering
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• v.34 no.3
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• pp.155-160
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• 2009

This study was attempted to quality characteristics of ginseng powder using molecular press dehydration(MD) method. Ginseng powder was dried using maltodextrin as dehydrating agents, and the quality of the ginseng powder was compared with that of freeze-drying and hot air-drying samples in terms of colors, moisture contents and grain size. The colors of ginseng powder using MD-drying and freeze-drying was better than hot air-dried ginseng powder. The moisture contents of ginseng powder using MD-drying was 9.49%, while freeze-drying was 4.14% and hot air-drying 11.71% after 72ball mill times. The grain size of ginseng powder using MD-drying and freeze-drying was better than hot air-drying ginseng powder. These results suggest that drying of ginseng powder using molecular press dehydration method is very efficient, because minimal cell destruction may be achieved.

• Food Science and Preservation
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• v.17 no.4
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• pp.478-486
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• 2010

The qualities of ginger prepared by an MPD (molecular press dehydration) method using maltodextrin, or dried using reused dehydration liquid, or prepared by freeze-drying or hot-air drying, were compared in terms of approximate overall composition, color, water absorption index, water solubility index, total sugar level, reducing sugar concentration, antioxidant activity, and gingerol content. The approximate composition of ginger prepared by the MPD method was lower in overall biochemical content than were those of gingers prepared using other methods. Ginger prepared by the MPD method retained the original ginger color. The water absorption and solubility index of ginger prepared by the MPD method (using maltodextrin) were better than those of gingers dried using other methods. The total sugar content did not change noticeably upon processing. The reducing sugar content of ginger prepared by hot-air drying was low. The antioxidant activity of ginger prepared by the MPD method was higher than that of freeze-dried and hot air-dried ginger samples, with values lower than those of BHA (3(2)-t-Butyl-4-hydroxyanisole) and BHT (2,6-Di-tert-butyl-4-methylphenol). The gingerol content of ginger prepared by the freeze-drying method was higher than that of gingers prepared by other methods. However, ginger constituents were present in the dehydration liquid used in the MPD method. The results indicate that both the MPD method (using maltodextrin) and the use of reused dehydration liquid are efficient methods by which ginger can be dried.

• Korean Journal of Food Science and Technology
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• v.42 no.4
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• pp.398-406
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• 2010

The purpose of this study was to determine the optimal mixing ratios for three different concentrations of maltodextrin, dehydration time, and cutting thickness to prepare gingers using molecular press dehydration (MPD) through response surface methodology (RSM) based on the dehydration rate, rehydration rate, and a sensory evaluation. As maltodextrin concentration increased, dehydration rate, rehydration rate, external, flavor, texture, overall acceptability of the gingers tended to be high, and the color tended to be low. As the dehydration time and cutting thickness increased, dehydration rate, rehydration rate and the sensory evaluation of the gingers tended to be high. The maltodextrin concentrations were 70-82%, dehydration time was 5.2-9.2 hr, and cutting thickness levels were 1.0-1.2 mm. The optimal mixing ratios, maltodextrin concentration, dehydration time, and cutting thickness for manufacturing the best quality of gingers using molecular press dehydration were 76%, 7.2 hr, and 1.1 mm, respectively.

• Food Science and Preservation
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• v.17 no.3
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• pp.358-364
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• 2010

Ginger was dried using maltodextrin or recycled dehydration liquid as dehydrating agents, and the quality of dried ginger was compared with that of freeze-dried and hot-air-dried samples in terms of color, moisture content, water activity, dehydration rate, rehydration rate, and sensory properties. Ginger prepared using molecular press dehydration (MPD) retained its original color. The dehydration rate increased when ginger was dried using a dehydrating agent. The rehydration rate was increased in ginger dried using such an agent. Both dehydration and rehydration rates were elevated with increasing concentrations of soluble solids in the dehydration liquid. The sensory qualities of ginger prepared using the MPD method were better than those of freeze-dried and hot air-dried samples. These results indicate that drying of ginger rhizomes using recycled dehydrating liquid is very efficient.

• Food Science and Preservation
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• v.16 no.6
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• pp.843-848
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• 2009

Green peppers were dried using maltodextrin and recycled dehydration liquid as dehydrating agents, and the quality of dried green pepper powders was compared with that of freeze-dried and hot air-dried samples in terms of moisture content, color, antioxidant activity, capsaicinoid level, and sensory acceptability. The moisture content of maltodextrin-treatedgreen pepper powder was higher than that of samples prepared using recycled dehydration liquid. The lightness (L) value rose with increasing concentrations of maltodextrin powder or liquid. The antioxidant activities of pepper powders prepared using the molecular press dehydration method were similar to that of alpha-tocopherol, and better than that offreeze-dried or hot air-dried samples. Capsaicinoid levels fell with increasing concentrations of maltodextrin powder and liquid. The sensory evaluation data on green pepper powders prepared using the molecular press dehydration method were better than those obtained when freeze-dried and hot air-dried samples were evaluated. These results indicate that drying of green pepper powders using maltodextrin and recycled dehydration liquid as dehydrating agents is very efficient.

• Fibers and Polymers
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• v.4 no.4
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• pp.182-187
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• 2003

Low molecular weight copolymers of maleic anhydride and vinyl acetate were prepared to develop formaldehyde free cross-linking agents. Since lower molecular weight is favorable for efficient penetration of the finishing agent into the cotton fibers in the padding process, the concentration of the initiator, chain transfer agent and the monomer ratios were varied to obtain copolymers of low molecular weights. The prepared polymers were characterized by GPC, $^1{H-NMR}$, FTIR, DSC and TGA. Copolymers of molecular weights of 2 000 to 10 000 were obtained and it was found that the most efficient method of controlling the molecular weight was by varying the monomer ratios. Poly(maleic anhydride-co-vinyl acetate) did not dissolve in water, but the maleic anhydride residue hydrolyzed within a few minutes to form poly(maleic acid-co-vinyl acetate) and dissolved in water. However, the maleic acid units undergo dehydration to form anhydride groups on heating above ${160}^{\circ}C$ to some extent even in the absence of catalysts. The possibility of using the copolymers as durable press finishing agent for cotton fabric was investigated. Lower molecular weight poly(maleic anhydride-co-vinyl acetate) copolymers were more efficient in introducing crease resistance, which appears to be due to the more efficient penetration of the cross-linking agent into cotton fabrics. The wrinkle recovery angles of cotton fabrics treated with poly(maleic anhydride-co-vinyl acetate) copolymers were slightly lower than those treated with DMDHEU and were higher when higher curing temperatures or higher concentrations of copolymer were used, and when catalyst, $NaH_2$$PO_2$, was added. The strength retention of the poly(maleic anhydride-co-vinyl acetate) treated cotton fabrics was excellent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.3
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• pp.435-442
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• 2010

This study was to investigate the quality characteristics of instant rice cake (Baekseolgi) with different concentrations of ginseng powder by molecular press dehydration (MPD) method. Baekseolgi was cooked using microwave oven, which is a useful cooking method because of reduced cooking time, even though it quickly takes moisture from food surface and lowers food quality. The result indicated that moisture content of Baekseolgi without ginseng powder was decreased; however, there was no significant difference in the Baekseolgi with ginseng powder with increased storage time for 24 hrs. The L value was decreased and a color value was increased with increasing concentrations of ginseng powder (p<0.05). There was no significant difference in the color values within the storage time. The hardness, gumminess, and chewiness of Baekseolgi without ginseng powder significantly changed as the storage time increased; in contrast, those of Baekseolgi with ginseng powder did not show such a significant change. The result of sensory evaluation showed that Baekseolgi with ginseng powder has higher scores in terms of color, flavor, taste, and overall acceptability than Baekseolgi without ginseng powder. Results of this study indicate the addition of ginseng powder to Baekseolgi improves moisture content, color value, and texture properties as well as sensory characteristics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.11
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• pp.1595-1599
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• 2009

Ginseng is one of the most well known medicinal plant in East Asia with many bioactivities. The purpose of this study was to evaluate the quality properties of cookies added with different concentrations (0, 1, 3, and 5%) of ginseng powder by molecular press dehydration (MPD) method. MPD was known to be an excellent tool for keeping taste and flavor without any loss of original materials. The results indicated no significant difference in the density of cookie dough with different concentrations of ginseng powder. The L color value was decreased and the a color values were increased with increasing concentrations of ginseng powder (p<0.05). However, there was no significant difference in the b values. Spread factor of cookie was not significantly different between 1% and 3%, but decreased at 5% (p<0.05). The hardness of cookies was significantly increased as ginseng powder concentration increased. The result of sensory score showed that cookie added with 1% ginseng powder had higher color, sweetness, overall acceptability scores than other samples. As a result of this study, quality of cookies with added 1% ginseng powder were the most suitable in terms of its color, texture, and sensory properties.