• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.289-294
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• 2007

This study was performed to investigate the effects of pre-soaking methods on the preparation of Rehmannia radix Preparata (R.P). The R. radix L (R.L) was soaked in distilled water and traditional Korean wine for 24 hr, then the soaked R.L was treated with a traditional nine-time steaming process. Next, catalpol, 5-hydroxymethyl-2-furaldehyde (5-HMF), polyphenols, flavonoids, antioxidant activities, and ACE inhibition activity were analyzed for the R.P produced by the different methods. The catalpol content of the R.L was 631.4 ppm, but the content decreased as steaming increased to 8-9 times. The 5-HMF, polyphenol, and flavonoid contents of the R.L were 0.12 mg/g, 5.09 mg/g, and 0.83 mg/g, respectively, and these increased gradually with increasing steaming times. As the steaming times of the distilled soaking water increased, the antioxidant activities of 1 mg/mL increased from 19.44% to 75.60% at 14 times of steaming. The ACE inhibition activities of 1 mg/mL of the distilled soaking water increased from 28.70% to 94.78% at 10 times of steaming, but decreased afterward.

• 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.34 no.4
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• pp.549-556
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• 2005

Response surface methodology (RSM) was applied in steaming and roasting processes of Polygonatum odoratum roots in order to monitor hypoglycemic components and sensory property. In steaming and roasting processes based on the central composite design with variations in steaming time $(60\~180\;min)$, roasting temperature $(110\~150^{\circ}C)$ and roasting time $(10\~50\;min)$, coefficients of determinations $(R^2)$ were 0.8691 (p<0.05), 0.8253 (p<0.l0), 0.8727 (p<0.05), 0.8706 (p<0.05) and 0.8316 (p<0.10) in soluble solid, stigmasterol, $\beta-sitosterol$, hypoglycemic component (total), and overall acceptability, respectively. The maximum value of soluble solid was $71.47\%$ in 65.24 min of steaming time, $126.93^{\circ}C$ of roasting temperature and 37.58 min of roasting time. The maximum value of hypoglycemic component (total) was $764.10\;{\mu}g/g$ in 107.76 min, $117.78^{\circ}C$ and 14.70 min. Meantime, the maximum value of overall acceptability was 6.89 in 126.04 min, $115.79^{\circ}C$ and 43.93 min. The predicted values in optimum conditions for hypoglycemic components and sensory property were in good agreement with experimental values.

• Korean journal of food and cookery science
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• v.28 no.6
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• pp.857-863
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• 2012

This study prepares dried sweet pumpkins to optimize pretreatment conditions of blanching, steaming and microwave heating and to investigate the quality characteristic of each method. The sweet pumpkin blanching treatment of moisture content decreased gradually with increasing temperature, and soluble solids, and weight loss was increased. Color temperature is lower, and a higher value of L value and b value increased. As for the sweet pumpkin steaming treatment of moisture content, it was observed that the longer the steaming time was decreased, sugar content was increased. Change of color in the L value, the longer the steaming time a and b values. Also, as for the microwave treatment of the sweet pumpkin, the longer the time the moisture content decreased, it slightly increased soluble solids and weight loss. Blanching showed the lowest hardness of texture, followed by steaming, and microwaves, in order. Penetration per 20 hours per type was determined by sensory evaluation of sugar, and sugar:fructose(1:2)ratio were higher in the composition.

• 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.

• 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.

• Culinary science and hospitality research
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• v.12 no.4 s.31
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• pp.247-258
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• 2006

This study was carried out to identify the change of glycoalkaloid contents and ascorbic acid in eggplant by parts and cooking methods. Content of glycoalkaloid by part of eggplant was the most in step part(A) as $31.1{\mu}g$ but it was shown that (A) and (C) contained more solamargine($6.9{\mu}g$) than solasonine, while (B) contained more solasonine($18.4{\mu}g$) than solamargine($6.9{\mu}g$). By cooking method, content of solamargine in eggplant varied; steaming ($6.2{\mu}g$), boiling ($7.0{\mu}g$), sauteing ($2.5{\mu}g$), microwave ($2.0{\mu}g$). Control group had $11.4{\mu}g$ solamargine and it contained solamargine most among them when boiled. Content of solasonine was in order of control ($4.88{\mu}g$)>steaming($3.40{\mu}g$)>microwave($1.2{\mu}g$)>boiling($0.6{\mu}g$)>sauteing(n.d.), and steaming showed the highest figure. As for content of ascorbic acid by part of eggplant, stem part had the most. That is, content of ascorbic acid decreased as from stem part under. Content of ascorbic acid of eggplant decreased greatly by cooking manipulation like other vegetables did, and the remaining amount showed control> sauteing> microwave> boiling> steaming in order.

• Applied Biological Chemistry
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• v.29 no.4
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• pp.372-374
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• 1986

Changes in moisture content and degrees of gelatinization during cooking of sweet potatoes by different cooking methods were studied. The samples were cooked by boiling, steaming, gas oven or microwave oven baking. Changes in the moisture content of sweet potato during cooking were +30.0% by boiling, +4.4% by steaming, -5.8% by gas oven baking, and -46.6% by microwave oven baking. The degrees of gelatinization of sweet potatoes were 83.8%, 75.7%, 73.0% and 67.7%, respectively.

• Journal of Ginseng Research
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• v.19 no.3
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• pp.249-253
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• 1995

In the browning reaction of Korean ginseng, it appears that enzymatic and non-enzymatic browning reaction occurred in the initial stage of heating fresh ginseng at low temperature, and then non-enzymatic browning reaction followed in the drying period after heating. Activation energy of the browning reaction for red ginseng was about 9.0 kcal/mol. Browning reaction of red ginseng was accede- rated with an increase in steaming time, and a great extent of browning reaction occurred between 60-90 min of steaming at 10$0^{\circ}C$. Browning pigments of red ginseng were mostly water soluble subset.

• Food Science and Preservation
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• v.17 no.3
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• pp.351-357
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• 2010

To decrease the intake of animal fat and cholesterol, changes in the physico-chemical characteristics of pork Boston butts cooked by different methods (boiling, steaming, baking, and frying) were investigated. Cooking weight loss and the drain rates of moisture, lipids, and cholesterol were highest during frying. The pH value increased during all cooking processes tested. The refractive index of meat fat increased markedly upon frying. The hardness, gumminess, and chewiness of meat were notably increased by frying. Springiness was not significantly affected by any cooking process, and cohesiveness was slightly increased by all cooking methods evaluated. The CIE $L^*$ (lightness) value was markedly increased upon steaming, and the CIE $a^*$ (redness) value decreased notably with boiling or steaming. The CIE $b^*$ (yellowness) value decreased slightly with either boiling or steaming, and was slightly increased when baking or frying was used. The fatty acid composition did not significantly change after cooking, except when meat was fried.