• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.1-7
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• 2002

This study deals with physical properties of Larch(Larix kaemferi Carr.) treated by steaming at temperatures above 100℃. Treatment conditions of this experiment were operated at regular intervals of 10℃ at temperature up to 130℃ for 10, 30 and 60 minutes by using the auto-clave. The Bending strength and compressive strength along the grain were slightly decreased with increasing the treating temperatures. There was no significant relations between wood strength and steaming temperatures. At the range from 120℃ to 130℃ of steaming temperature, it was considered that the change of composition and structure in cell wall was changed due to release of stresses. Water absorption characteristics were not affected by steaming temperature. In this experiment limits, it was concluded that physical properties of wood by steaming treatment were affected more largely by wood density than by treating temperature.

• Korean Journal of Human Ecology
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• v.22 no.3
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• pp.485-492
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• 2013

The temperature changes of dumpling(mandu) during cooking process were examined and the effects of time-temperature and/or time-size interactions on internal temperature were studied. Mandu was purchased from local markets and classified by its weight(small, medium, and large). Boiling, steaming, pan frying, and deep fat frying were adopted. Internal temperature was measured with a food thermometer in every one minute. The internal temperature of mandu increased over time in every cooking process(p<0.05). After three minutes the internal temperature of mandu in boiling, pan frying, and deep fat frying reached over at $74^{\circ}C$, which is high enough temperature to kill the harmful bacteria, but not in steaming. The internal temperature of mandu was significantly affected by cooking time, size, and both in boiling, steaming, and deep fat frying(p<0.05). There were significant differences between the internal and surface temperatures of mandu in the cooking processes except pan frying in three minutes(p<0.05). The results of this study indicate three minutes' cooking of the mandu by boiling, pan frying, and deep fat frying is safe enough to eat. However, longer steaming time is needed in order to reach safe temperature. This study also indicates the cooking time and size of mandu appear to be major factors in determining the internal temperature achieved at $74^{\circ}C$. More research is needed to check time to reach a safe temperature in the cooking process of mandu by steaming.

• 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.

• Journal of the Korea Furniture Society
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• v.11 no.2
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• pp.1-6
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• 2000

This study was carried out to investigate the effect of steaming on mechanical properties of heat-compressed wood specimens. The specimens for this mechanical strength tests were prepared to super-heated steam treatment after compression to the radial direction of sonamu (Pinus densiflora). The specimen's size is $50(L)mm{\times}20(R)mm{\times}17(T)mm$. Steaming temperature and treatment time is $120^{\circ}C$ and 20, 40, 60, 80, 100 minutes, respectively. Modulus of elasticity(MOE) in compressive test is directly proportional to steaming time. On the other hand, modulus of elasticity in bending test between steaming and not steaming after heat-compressed wood is similar irrespective of steaming time. The reason for this phenomenon is not clear yet.

• Korean Journal of Medicinal Crop Science
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• v.27 no.2
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• pp.86-95
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• 2019

Background: Depending on the processing method, the raw materials constituents change in various ways. In particular, a heat treatment process, such as steaming, changes the color and aroma of a raw material to increase its palatability and number of physiologically active ingredients. Methods and Results: In the present study, the effects of the steaming temperature and time on the yield, color, proximal composition, and total polyphenol and ginsenoside content of a 4-year-old ginseng root were analyzed. The yield tended to decrease with the increase of steaming time at each temperature and the total ginsenoside content increased with increasing of steaming temperature except at $80^{\circ}C$. Conclusions: These results suggest that steaming at $100^{\circ}C$ for 6 - 9 hours or at $110^{\circ}C$ for 3 - 6 hours is suitable for increasing total polyphenol and ginsenoside content with less yield reduction in a 4-year-old ginseng root.

• Journal of the Korean Wood Science and Technology
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• v.30 no.2
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• pp.102-107
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• 2002

This study deals with a physical properties of Larch(Larix kaemferi Carr.) treated at temperatures above 100℃. Treatment conditions of this experiment were operated at regular intervals of 20℃ at temperature up to 180℃ for 10, 30, 60 and 90 minutes by using the bomb, respectively. The results of this study were as follows : 1) The density was decreased with increasing the times and temperatures of steaming. 2) It was considered that the steaming treated specimen's higher shrinkage compared to control was due to change of composition and structure in cell wall. 3) The warpage of half edge grain specimen was decreased by high temperature steaming.

• Journal of Ginseng Research
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• v.41 no.3
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• pp.347-352
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• 2017

Background: Panax ginseng (PG) has a long history of use in Asian medicine because of its multiple pharmacological activities. It has been considered that PG in a type of white ginseng may induce undesirable thermogenic effects, but not in a type of red ginseng. However, there is a lack of evidence about the correlation between ginsenoside and thermogenesis. Methods: We investigated the effects of PG with different ginsenoside compositions on body temperature, blood pressure, and thermogenesis-related factors in rats. Results: With increasing steaming time (0 h, 3 h, 6 h, and 9 h), the production of protopanaxadiol ginsenosides increased, whereas protopanaxatriol ginsenosides decreased in white ginseng. In both short- and long-term studies, administration of four ginseng extracts prepared at different steaming times did not induce significant changes in body temperature (skin, tail, and rectum) and blood pressure of rats compared to saline control. In addition, there were no significant differences in the molecular markers related to thermogenesis (p > 0.05), mRNA expressions of peroxisome proliferator-activated receptor-gamma coactivator-$1{\alpha}$ and uncoupling protein 1 in brown adipose tissue, as well as the serum levels of interleukin-6, inducible nitric oxide synthase, and nitrite among the treatment groups. Conclusion: These observations indicate that the potential undesirable effects of PG on body temperature could not be explained by the difference in ginsenoside composition.

• Food Science and Preservation
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• v.12 no.2
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• pp.166-172
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• 2005

Response surface methodology (RSM) was applied to monitor the effects of steaming and roasting conditions of Polygonatum odoratum roots an total phenolics content, electron donating ability (EDA) and nitrite-scavenging ability (NSA) of the extract. In steaming and roasting processes based on the central composite design. with variations in steaming time $(60\~180\;min)$, roasting temperature $(110\~150\;min)$ and roasting time $(10\~50\;min)$, coefficients of determinations $(R^2)$ were 0.9356 (p<0.01) in total phenolics, 0.9578 (p<0.01) in EDA and 0.9436 (p<0.01) in NSA (pH 3.0). The maximum value of total phenolics was $2847.67\;mg\%$ at 135.59 min of steaming time, $143.84^{\circ}C$ of roasting temperature and 43.47 min of roasting time. The maximum value of EDA was $75.00\%$ in 108.98 min, $135.56^{\circ}C$ and 48.86 min. The maximum value of NSA (pH 3.0) was $87.38\%$ in 162.80 min, $143.88^{\circ}C$ and 31.97 min, respectively. Total phenolics content of the extract was influenced by heating conditions in the order of roasting temperature, steaming time and roasting time. While EDA and NSA were appreciably influenced by roasting time, followed by roasting temperature and steaming time.

• Food Science and Preservation
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• v.4 no.2
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• pp.155-162
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• 1997

This work was designed to determine the effect of steaming-Pretreatment on Physicochemical and functional properties of roasted Polygonatum odoratum roots. Steaming treatments led to some reduction in the contents of water solubles, such as total solid, reducing sugar and free-amino nitrogen of the unroasted samples. Moreover, roasting processing caused decrease in reducing sugar and free-amino acid, with increase in total soluble solid and browning color of the samples, which showed the dependence of steaming treatment as well as roasting temperature. Electron-donating ability and nitrite-scavenging ratio of the samples were also highly developed along with roasting processing at 17$0^{\circ}C$ within 35min. Considering the physicochemical and some functional parameters of water extracts of roasted samples, roasting at above 14$0^{\circ}C$ for over 55min or at 17$0^{\circ}C$ for around 35min was recommendable for the higher quality of Polygonatum odoritum tea, which conditions were similarly adapted for both steamed and unsteamed samples.

• Korean Chemical Engineering Research
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• v.52 no.5
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• pp.587-591
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• 2014

Experiments for a control method that enhances the yield to produce high quality red ginsengs have been performed. In the first steaming process of a series of processes to produce red ginsengs from raw ginsengs, there occur several undesirable defects on ginsengs such as cracks of ginseng body, inside cavity and inside white. These defects lead to deterioration in product qualities. Therefore an improved control method that minimizes these undesirable defects is needed in order to increase the yield of high quality red ginsengs. Until these days, the steaming process control methods such as controlling the steaming temperature and/or pressure have been studied. However, such control methods are not adequate enough to minimize the undesirable defects in steamed ginsengs. On the other hand, in this experiment, we suggest a control method that minimizes the undesirable defects through a weight control of steamed ginsengs, keeping the steaming temperature at $96{\sim}99^{\circ}C$ as usual. Experiments with the weight control show that amount of cracks on the steamed ginseng body can be reduced.