• Korean Journal of Food Science and Technology
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• v.43 no.6
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• pp.696-701
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• 2011

To evaluate the processing adaptability of taro flours, the physicochemical properties of taro flour with different drying, roasting and steaming conditions were investigated. The moisture content and total dietary fiber were decreased as temperature increased with hot-air drying. Freeze-dried taro flours showed the highest vitamin C contents. Taro flours made by freeze-drying and hot-air drying showed significantly higher total dietary fiber content than those with roasting and steaming process. Steamed taro flours had the highest water absorption index, while hot-air dried and freeze dried taro flours had the highest water solubility index. No differences were displayed in the differential scanning calorimetry (DSC) thermal characteristics among hot-air dried and freeze dried taro flours. Roasted taro displayed decreased onset temperature and peak temperature as roasting temperature increased. Using a rapid visco-analyzer, the peak viscosity, through viscosity, and final viscosity of dried and steamed taro flours were higher than roasted taro flours, whereas the set back value, which is a prediction of retrogradation, decreased with steaming processing. From those results, it could be concluded that hotair dried taro flours, which have high gelatinization viscosity, are beneficial in imparting viscosity to dough products and hot-air drying after steaming taro flours, which retard retrogradation, is good for porridge and flake base products.

• The Korean Journal of Food And Nutrition
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• v.12 no.3
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• pp.258-264
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• 1999

This study was carried out to investigate the status in weight loss yield of edible meat quality and free amino acid contents of the snow crab(Chionoectes japonicus) by steaming and various drying treat-ment. Change of body weight loss in steaming treatment sample were 20.48∼26.72% and yield of edible meat of steaming sample was higher than raw sample(p<0.05) The pH value was increased with steam-ing and drying and pH of trunk meat was more increased than leg meat. Volatile basic nitrogen(VBN) content of vacuum dried sample was highest and VBN of hot-air and freezing dried sample were about 10mg%. Content of vaccum dried sample wre 41.33 and 48,56mg%. Thirty kind of free amino acids dectected in the snow crab and changes of free amino acid in leg meat were markedly reduced by vacuum drying and the reducing ratio of leg meat by freeze drying was little. The major free amino acid of leg and trunk meat were 39.94% 46.78% respectively. The formation of flavor free amino acid in freezing dried sample were high but its hot-air aried sample were small.

• Korean Journal of Medicinal Crop Science
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• v.19 no.5
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• pp.354-361
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• 2011

In order to product dry goods of Gastrodiae Rhizoma with high quality, tubers were treated with various dry methods such as cutting, drying methods and steaming. In cutting than no cutting, they were shown shorter drying hours and lower drying yield. Drying hours in freeze drying was shorter than those of hot air and far-infrared ray. Total polyphenol content was higher in cutting than no cutting. According to steaming, it was increased in freeze drying but decreased rapidly in the other dry methods. Among all treatments, hot air dry treatment with cutting and no steaming had the highest total polyphenol content. Gastrodin and 4-hydroxybenzyl alcohol contents generally were similar or higher in cutting than no cutting. By steaming, gastrodin content in freeze drying was decreased but 4-hydroxybenzyl alcohol content was increased. But hot-air and infrared ray dry, they were shown opposite results. Gastrodin and 4-hydroxybenzyl alcohol contents showed opposite reaction to each other and were shown various response by dry methods.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.5
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• pp.823-829
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• 2011

This study was performed to obtain the good processing in the Rehmanniae Radix Preparata. In this study, we investigated the comparative analysis for steamed and hot-air dried Rehmanniae Radix Preparata. The results were obtained as follows : Through loss on drying analysis with each additional processing of Rehmanniae Radix preparata, there was gradual increase. Through ash analysis with each additional processing of Rehmanniae Radix preparata, there was slight increase. Rehmanniae Radix preparata had several inorganic components such as K, P, Mg, Ca, Cl, Al. P and Mg were increased gradually with each additional processing of Rehmanniae Radix Preparata. But Ca was decreased with each additional processing. We identitied 24 kinds of volatile components from extracts of various processed Rehmanniae Radix Preparata through componential analysis using GC/MS. From GC/MS analysis, we found out the content of 5-HMF Rehmanniae Radix Preparata steamed over 7 times was suitable. 5-HMF's content of 9 times steamed Rehmanniae Radix Preparata gained from GC/MS analysis is 70-fold higher than gained from HPLC. The more it is repeating steamed and hot-air dried, the more toxic volatile compound of Rehmanniae Radix Preparata is removed. Taken together, these results suggested that Rehmanniae Radix Preparata had component (especially 5-HMF) changes according to different processed steaming and hot-air drying.

• Korean Journal of Food Science and Technology
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• v.45 no.6
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• pp.742-746
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• 2013

This study was conducted to investigate the effect of different steaming and drying temperature conditions on the physicochemical characteristics of pumpkin powder. All the samples were steamed for 30 or 60 s and then were dried using hot air at 40, 50, 60, and $70^{\circ}C$. The moisture content decreased with an increase in the hot-air drying temperature, while the soluble solid content and yield increased. The color values, L, a, and b of the pumpkin powder decreased with increasing hot-air drying temperature. The pumpkin powder, which was steamed for 60 s had the highest water absorption and water solubility indexes. The carotenoid content of pumpkin powder was mostly destroyed with the increase in the steaming and drying temperatures. The total sugar and reducing sugar contents increased with increasing steaming and drying temperatures. Thus, the steaming and dehydration temperature conditions influenced the physicochemical characteristics of the pumpkin powder.

• 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.

• Food Science and Preservation
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• v.24 no.1
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• pp.21-26
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• 2017

This study was performed to determine the effects of preconditioning process (Con, roasting; SR, steaming and roasting; HDR, hot air drying and roasting; SHDR, steaming hot air drying and roasting) and roasting on the antioxidant and physicochemical properties of acorn (Quercus species) tea. Each sample was extracted in $95^{\circ}C$ hot water for 5 min. The color values of lightness and yellowness were the highest in HDR, and redness were the highest in the control. The total sugar content was the highest in SHDR. Total polyphenol and total flavonoid contents of HDR tea were higher than those of teas prepared by the different processes. DPPH and ABTS radical scavenging abilities of HDR were 75.66% and 98.16%, respectively, which were higher than those of other teas. In the sensory evaluation, HDR tea was ranked significantly higher than other teas in terms of flavor, taste and overall acceptability. Finally, acorn tea treated with drying was superior to other treatments in antioxidant and quality properties. The result suggests that HDR can be applied to acorn tea to achieve better quality and functionality.

• Food Science and Preservation
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• v.21 no.5
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• pp.646-651
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• 2014

To evaluate the processing adaptability of burdock (Arctium lappa L) tea, the physicochemical properties of burdock tea treated with steaming and roasting were investigated. The tea treatments included hot-air drying after roasting (HDR, drying at $60^{\circ}C$ for 6 hr), steaming after hot-air drying (SHD, steaming at $100^{\circ}C$ for 10 min), and steaming and then hot-air drying followed by roasting (SHDR, roasting at $250^{\circ}C$ for 3 min). The physicochemical properties, antioxidant activities, and sensory properties of the HDR, SHD, and SHDR teas were measured in hot water, and the tea was extracted from each sample. The color values of lightness (L) and yellowness (b) were lower in the HDR and SHDR teas, and the total sugar content of the SHDR tea was significantly higher than that of the other teas. The ABTS and DPPH radical scavenging abilities of the SHDR tea with a 500 mg% concentration were significantly higher than those of the SHD tea. In the sensory evaluation, the SHDR tea was ranked significantly higher than the other samples as to its color, flavor, taste, and overall acceptability. The results suggest that SHDR can be applied to burdock tea to achieve high quality and functionality.

• Korean Journal of Medicinal Crop Science
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• v.20 no.1
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• pp.27-35
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• 2012

This study was conducted to investigate changes in composition of ginsenosides and color of processed ginsengs prepared by different steaming-drying times. Processed ginsengs were prepared from white ginseng with skin by 9-time repeated steaming at $96^{\circ}C$ for 3 hours and followed by hot air-drying at $50^{\circ}C$ for 24 hours. As the times of steaming processes increased, lightness (L value) decreased and redness (a value) increased in color of ginseng powders. Crude saponin contents and ginsenosides compositions in processed ginsengs prepared by different steaming-drying times were investigated using the HPLC method, respecively. Crude saponin contents according to increasing steaming-drying times decreased in some degree. In the case of major ginsenosides, the contents of $Rb_1$, $Rb_2$, Rc, Rd, Rf, Re, $RG_1$, Re were decreased with increase in steamimg times, but those of $Rh_1$, $Rg_3$, $Rk_1$ were increased after especially 3 times of steaming processes. Interestingly, in black ginseng were prepared by 9 times steaming processes, the content of ginsenoside $Rg_3$ was 8.20 mg/g, approximately 18 times higher than that (0.46 mg/g) in red ginseng. In addition, the ratio of the protopanaxadiol group and protopanaxatiol group (PD/PT) were increased from 1.9 to 8.4 due to increasing times of steamming process.

• Journal of Applied Biological Chemistry
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• v.55 no.3
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• pp.185-189
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• 2012

This study was conducted to investigate the effect of different steam condition and dehydration condition on physicochemical characteristics of Olbyeossal made from Waxy rice. All samples were steamed at $95-100^{\circ}C$ for 60 min or at $121^{\circ}C$ for 20 min and then were dehydrated using hot air 45, 60, $80^{\circ}C$ and sun-dried to achieve moisture contents 13-15%. Initial pasting temperature of Olbyeossal was the lower than that of nontreatment sample by parboiling. The combination in steaming $95-100^{\circ}C$ and hot drying at $45-60^{\circ}C$ was showed appropriate pasting properties compared with other condition. The hardness of Olbyeossal was significantly affected by steaming and dehydration condition. The hardness of Olbyeossal showed the higher value for steaming at $121^{\circ}C$ than $95-100^{\circ}C$. The water binding capacity (WBC) and swelling power (SP) were higher steaming at $121^{\circ}C$ than $95-100^{\circ}C$. No significant differences on WBC and SP of Olbyeossal by dehydration condition were observed. As the sensory evaluation results, the combination in steaming at $121^{\circ}C$ and hot-air drying at 45 or $80^{\circ}C$ led to increase preference for appearance, color, taste and overall acceptability. These results indicate that steaming and dehydration condition were affecting factor on physicochemical characteristics of Olbyeossal.