• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.212-217
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• 2004

To make the germinated buckwheat tea, soluble solid contents, total flavonoid contents and organoleptic properties were investigated under various steaming time and drying temperature. The optimum condition of soluble solid contents were 6.93 min of steaming time and 73.59$^{\circ}C$ of drying temperature. Total flavonoid contents were maximum under the condition of 5.22 min of steaming time and 79.05$^{\circ}C$ of drying temperature. The optimum condition of overall palatability was 6.00 min of steaming time and 77.33$^{\circ}C$ of drying temperature. The optimum ranges of soluble solid contents, total flavonoid contents and overall palatability of the tea were 5.4∼7.0 min of steaming time and 75∼8$0^{\circ}C$ of drying temperature. The values expected in the optimum ranges were also similar to the experimental values.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.45-49
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• 2010

To reduce the astringent taste of lotus root, the effects of various treatment methods such as drying, soaking, steaming and roasting on the physicochemical properties and sensory characteristics were investigated. The following process conditions were selected: 1) drying (D), 2) soaking followed by drying ($SK{\rightarrow}D$), 3) steaming followed by drying ($ST{\rightarrow}D$), 4) drying followed by roasting ($D{\rightarrow}R$), 5) soaking and then drying followed by roasting ($SK{\rightarrow}D{\rightarrow}R$), 6) steaming and then drying followed by roasting ($ST{\rightarrow}D{\rightarrow$}. The tannin content of the lotus root was lowest when it was treated by steaming followed by drying ($ST{\rightarrow}D$). The astringent taste of lotus root was reduced by steaming, and the roasted taste was improved by roasting in terms of sensory and flavor characteristics. Consequently, lotus root treated by steaming and then drying followed by roasting ($ST{\rightarrow}D{\rightarrow}R$) showed the highest preference with respect to astringent and roasted taste.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.2
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• pp.136-141
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• 2000

This study was conducted to analyze the properties of the roasted dandelion tea prepared after various pre-treatments such as pre-drying, steaming and air blast drying. The dandelion tea was prepared by roasting the pre-treated dandelion leaves and its total yield, pH, soluble solid content, turbidity, browning and sensory value were evaluated. Total yield and soluble solid content were the highest in case of air blast drying. Turbidity and browning degree were similar in all the teas regardless of their pre-treatment including pre-drying, steaming or air blast drying. The best palatability in the sensory evaluation was obtained at the steaming condition for 60 sec without pre-drying. Longer air blast drying time resulted in the increase in the a and b values. turbidity, browning degree, total yield and soluble solid content in the air blast dried tea.

• Journal of Microbiology and Biotechnology
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• v.29 no.2
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• pp.222-229
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• 2019

Korean ginseng (Panax ginseng Meyer) was processed by drying, steaming, or puffing, and the effects of these processes on the ginsenoside profile were investigated. The main root of 4-year-old raw Korean ginseng was dried to produce white ginseng. Steaming, followed by drying, was employed to produce red or black ginseng. In addition, these three varieties of processed ginseng were puffed using a rotational puffing gun. Puffed ginseng showed significantly higher extraction yields of ginsenosides (49.87-58.60 g solid extract/100 g of sample) and crude saponin content (59.40-63.87 mg saponin/g of dried ginseng) than non-puffed ginseng, respectively. Moreover, puffing effectively transformed the major ginsenosides (Rb1, Rb2, Rc, Rd, Re, and Rg1) of ginseng into minor ones (F2, Rg3, Rk1, and Rg5), comparable to the steaming process effect on the levels of the transformed ginsenosides. However, steaming takes much longer (4 to 36 days) than puffing (less than 30 min) for ginsenoside transformation. Consequently, puffing may be an effective and economical technique for enhancing the extraction yield and levels of minor ginsenosides responsible for the major biological activities of ginseng.

• Journal of Ginseng Research
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• v.28 no.3
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• pp.143-148
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• 2004

Brown color intensity has been a major factor to estimate the quality of red ginseng and its products. This study deals with the relationship between the browning reaction of ginseng root and two compounds, arginyl-fructosyl-glucose(Arg-fru-glc) and arginyl-fructose (Arg-fru), in the model system of steaming and heat-drying processes for the preparation of red ginseng. During the steaming process, a marked decrease of starch and a considerable formation of maltose occurred in main roots of raw ginseng, but the formation of glucose was scarcely observed. After the heat-drying process, the brown color intensity of the powdered preparation of steamed main roots was 3 to 4 times higher than that of the powdered preparation of raw main roots. Also, when the heat- drying process was done with the addition of L-arginine, brown color intensity of the powdered preparation of steamed main roots was 12 to 13 times higher than that of the powdered preparation of raw main roots. The amount ratios of browning reaction products formed from sugar compounds and amino acids in the model system of steaming and heat-drying treatments in vitro were in order of xylose > glucose > fructose > maltose > dextrin (DE 9) > sucrose > dextrin (DE 8) and soluble starch. Each solution of Arg-fru-glc and Arg-fru that were synthesized chemically from maltose plus L-arginine and glucose plus L-arginine, respectively, changed from colorless to brown color during the heat-drying treatment. Amino acids or sugars were effective on the acceleration of each browning reaction of Arg-fru-gIc and Arg-fru during the heat-drying treatment.

• 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.

• Food Science and Preservation
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• v.19 no.5
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• pp.703-711
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• 2012

This study was conducted to investigate the quality and organoleptic properties of dehydrated onions with steaming and heating. Sliced onions were treated as follows: steaming time ($X_1$, 5~25 min); drying temperature ($X_2$, $55{\sim}70^{\circ}C$) and drying time ($X_3$, 4~20 hr). All the variables were modelled and analyzed using a central composite design and response surface methodology (RSM). The coefficients ($R^2$) of the water content and water activity model induced from RSM were 0.9514 (p<0.01) and 0.9455 (p<0.01), respectively. The water content and water activity were affected by the drying temperature and time. The $R^2$ on the models of Hunter's L, a, b values were 0.9419 (p<0.05), 0.8818 (p<0.01) and 0.9360 (p<0.01), respectively. Hunter's L, a, b values were affected by the drying temperature and time, but Hunter's b value was not affected by the steaming time. In addition, the $R^2$ on the models of overall palatability was 0.8867 (p<0.05). The maximum palatability response was 5.92 when the steaming time was 13.14 min, the drying temperature was $63.11^{\circ}C$ and the drying time was 14.49 hr.

• 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.

• 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 Physiology & Pathology in Korean Medicine
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• v.22 no.6
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• pp.1557-1561
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• 2008

Red ginseng possibly has new ingredients converted during steaming and dry process from fresh ginseng. Kujeungkupo method which means 9 repetitive steamings and dryings process was used for the production of red ginseng from 6-year old ginseng roots. Saponin was extracted from each red ginseng produced at the 1st, 3rd, 5th, 7th, and 9th during the steaming and drying treatment, and we analyzed saponin content with TLC. Minor saponins, such as ginsenoside-Rg3, -Rh2, compound K, and F2, increased as the process time of steaming and drying, but major saponins (ginsenoside-Rb1, -Rb2, -Rc, -Rd, -Re, -Rf, -Rg1) were decreased. Major saponins were yet observed almost at the 1st process, then degraded as the increasing time of steaming and drying process. Especially, ginsenoside-Re and -Rg were observed as considerable amount after the 1st treatment, but there were no trace of them after the 9th treatment. Ginsenoside-Rg1, -Rb2, and -Rb1 were also reduced remarkedly by 96.6%, 96%, and 92.3%, respectively. Minor saponins were increased significantly, especially for ginsenoside-Rg3 and ginsenoside-F2. These results suggest that Kujeungkupo method is the very useful method for the production of minor ginsenoside-Rg3 and -Rh2.