• The Korean Journal of Food And Nutrition
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• v.12 no.5
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• pp.484-489
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• 1999

Rosting conditions for improvement of viscosity and sensory properties of sea tangle extracts were investigated. The supernatant % solid yield and crude protein yield were increased by increasing of roasting temperature and times. The highest contents of algin was obtained in roasting temperature of 175$^{\circ}C$ ash contents were increased by roasting temperature increasing. Viscosities of sea tangle extract were significantly decreased by increasing of roasting temperature and time upto 175$^{\circ}C$ and 10 mins more than further roasting conditions. The pH of sea tangle extracts slightly decreased from 5.94 to 5.83 in the roasting of 15$0^{\circ}C$ however at temperature more than 175$^{\circ}C$ its pH was increased by increasing of temperature and time. According to increase of roasting temperature and time Lightness (L value) were significantly decreased and redness (a value) and yellowness (b value) reached the highest value in the roasting of 20$0^{\circ}C$ 15 min. or 175$^{\circ}C$ 30 min and after that its value were decreased. The odor characteristics showed that sea tangle extract prepared by roasting of 175$^{\circ}C$ 10mins was slightly reduced in intensity of savory and seaweed taste but significantly low in intensity of nauseous taste and high in intensity of roasted taste and accetability. Overall data suggested 175$^{\circ}C$ 10min was the most effective roasting conditions for improvement of viscosity and sensory properties of sea tangle extract.

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.776-783
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• 1997

Response surface methodology was applied to determine the optimum roasting conditions (roasting temperature and time) for the high-quality Polygonatum odoratum tea which has been roasting with a traditional means. As quality criteria of Polygonatum odoratum tea, water-soluble solids, browning color, total phenolic compounds and electron-donating ability were proportionally increased with increased temperature and time of roasting conditions up to around $145^{\circ}C$ and 55 min, respectively, while they were decreased under the extended-roasting conditions. The optimum roasting temperature and time based on the organoleptic overall acceptability were $146^{\circ}C$ and 52 min, respectively. On the basis of superimposed contour maps for the tea characteristics, the optimum range of roasting conditions were $135{\sim}140^{\circ}C$ and $58{\sim}64$ min. Predicted values at the optimum conditions $(137^{\circ}C,\;60\;min)$ were in good agreement with experimental values.

• Journal of Microbiology and Biotechnology
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• v.30 no.11
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• pp.1706-1719
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• 2020

The objective of this study was to optimize the conditions for enhancing the antioxidant properties of sword bean (Canavalia gladiata) as a coffee substitute in two processing methods, roasting and grinding. The optimum conditions for removing off-flavor of the bean and maximizing functionality and efficiency were light roasting and cryogenic grinding (< 53 ㎛). In these conditions, extraction yield was 16.75%, total phenolic content (TPC) was 69.82 ± 0.35 mg gallic acid equivalents/g, and total flavonoid content (TFC) was 168.81 ± 1.64 mg quercetin equivalents/100 g. The antioxidant properties were 77.58 ± 0.27% for DPPH radical scavenging activity and 58.02 ± 0.76 mg Trolox equivalents/g for ABTS radical scavenging activity. The values for TFC and ABTS radical scavenging activity were significantly higher (p < 0.05) than in other conditions, and TPC and DPPH radical scavenging activity were second highest in lightly roasted beans, following raw beans. HS-SPME/GC-MS analysis confirmed that the amino acids and carbohydrates, which are the main components of sword bean, were condensed into other volatile flavor compounds, such as derivatives of furan, pyrazine, and pyrrole during roasting. Roasted and cryogenically ground (cryo-ground) sword beans showed higher functionality in terms of TFC, DPPH, and ABTS radical scavenging activities compared to those of coffee. Overall results showed that light roasting and cryogenic grinding are the most suitable processing conditions for enhancing the bioactivity of sword beans.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.1
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• pp.80-86
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• 1998

This work was designed to determine the optimum roasting conditions with application of a pressure roaster for improving the roasting process of the Polygonatum sibiricum tea which has been roasting with a traditional method. Soluble solid content of the Polygonatum cibiricum tea was 63.16% in the tea roasted at 0.85kgf/$\textrm{cm}^2$(roasting pressure) and 13.9min(roasting time) which were maximum point by the ridge analysis. The optimum conditions predicted for each corresponding sensory properties of the Polygonatum cibirium tea were 0.87kgf/$\textrm{cm}^2$ and 9.2min in color, 0.89kgf/$\textrm{cm}^2$ and 9.7min in sweet 0.72kgf/$\textrm{cm}^2$ and 5.4min in burnt flavor, 0.89kgf/$\textrm{cm}^2$ and 9.9min in appetizing flavor, 0.87kgf/$\textrm{cm}^2$ and 9.3min in aftertaste, 0.89kgf/$\textrm{cm}^2$ and 10.0min in aroma, and 0.88kgf/$\textrm{cm}^2$ and 9.6min in overall acceptability of the tea. The optimum conditions based on the soluble solid content and sensory properties of the Polygonatum cibiricum tea, were 0.83~0.88kgf/$\textrm{cm}^2$ and 9.7~10.4min.

• Korean Journal of Food Preservation
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• v.15 no.3
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• pp.396-404
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• 2008

This study investigated the functional properties of lateral roots of red ginseng following roasting treatment The ten different conditions, based on the central composite design for roasting parameters, were pre-established according to roasting temperature($140{\sim}240^{\circ}C$) and time($5{\sim}25\;min$). The functional characteristics were monitored using response surface methodology, whereby polynomial equations and correlation coefficients were investigated between roasting conditions. The functional properties of the samples were affected more by roasting time than temperature. The optimal roasting condition ranges for maximizing the functional qualities of lateral roots of red ginseng were predicted to be a roasting temperature of $194.5-210.9^{\circ}C$, and a roasting time of 13.8-20.0 min.

• Proceedings of the Plant Resources Society of Korea Conference
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• pp.88-88
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• 2018

Coffee is one of the most popular drinks in the world. Roasting process of coffee bean is one of major steps to make coffee, however, there are few studies which analyzed chemical compounds in intermediate state of roasting coffee beans due to technical limitations to get coffee beans with the same roasting condition. We utilized Stronghold S7 pro roasting machine which guarantees the saming roasting conditions repletively with the aid of precise computer to control heat sources to get 20 steps (every 30 seconds) of roasted coffee beans during roasting process (10 min in total). Along with roasting process, phenolic compounds were decreased, which can be explained that roasting process cause phenolic compounds degradation. Caffeine is almost constant during roasting, reflecting that caffeine is not affected in roasting process. These samples presents that organic acids significantly increase along with the roasting process by HPLC analysis. With additional analysis of coffee beans, such as moisture contents, pH, as well as coffee tastes, our analysis will show detailed process of chemical compounds of coffee beans during roasting process.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.654-658
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• 2000

Flavor components focused on the methyl pyrazines(2,3-dimethyl pyrazine, 2,3,5-trimethyl pyrazine, tetramethyl pyrazine) of microwave-roasted cocoa beans were determined and compared with those of conventionally-roasted cocoa beans. Domestic microwave oven was modified to design the microwave roasting system. Temperature measurement technique using thermocouple probes was developed to determine the center temperature of cocoa beans during microwave roasting. Microwave roasting was carried out under two different conditions. Under the first condition, roasting time was fixed to 30 min, while roasting temperature was varied to $110^{\circ}C,\;120^{\circ}C,\;130^{\circ}C,\;140^{\circ}C,\;and\;150^{\circ}C$ Under the second condition, roasting temperature was fixed to $130^{\circ}C$, while roasting time was varied to 5 min, 10 min, 20 min, and 30 min. Conventional roasting was done at $120^{\circ}C$ for 15 min as a reference. Amount of methyl pyrazines and their ratios were influenced by microwave roasting temperature and roasting time. The most suitable methyl pyrazine ratio of cocoa beans was obtained at $140^{\circ}C$ for 30 min of microwave roasting.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.2
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• pp.129-135
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• 2000

This study was attempted to develop dandelion tea under various roasting conditions. The quality properties of tea were evaluated by measuring soluble solid. total yield, pH, color value, turbidity, browning degree, and sensory evaluation induced by various roasting time and temperature. The total yield and soluble solid content were the highest at the roasting process at 23$0^{\circ}C$ for 10 min. pH value was higher in non-treatment than pre-drying treatment and was not different among the roasting times. L value was reduced with increasing roasting time. Turbidity and browning degree of dandelion tea were the highest at the roasting condition at 23$0^{\circ}C$ for 10 min. Palatability was the highest at the roasting condition at 23$0^{\circ}C$ for 5 min without pre-drying. The higher solid yield was obtained with an increase in roasting temperature. Turbidity and browning degree increased under the roasting conditions at 230 and 26$0^{\circ}C$, respectively. Palatability in sensory evaluation increased at the roasting condition at 26$0^{\circ}C$ for 10 min. The higher savory taste value was obtained with an increase in roasting temperature.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.4
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• pp.365-377
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• 2017

The objective of this study was to investigate the sensory quality characteristics of coffee under various processing and roasting conditions of green beans. Colombia green bean samples were obtained from three processing methods: natural, pulped-natural, and washed methods. The green beans were roasted differently according to Agtron number: light (Agrton #65), medium (Agtron #55), and dark (Agtron #45). Moisture content, density, color value, pH, and total dissolved solid contents (TDS) were measured, and quantitative descriptive analysis (QDA) with 23 sensory attributes was performed for nine coffee samples. Hunter L values were significantly elevated with the degree of processing but reduced with roasting intensity. The pH values of the nine coffee samples were 5.6~6.2 and significantly increased with intensity of roasting. TDS decreased with an increase in processing and increased with roasting intensity. QDA results show that smoky aroma and nutty and chocolate flavor significantly increased while fruit and floral aroma decreased with intensity of processing. The attributes of brownness, oily surface, smoky aroma, bitter and burnt flavor, and greasy and heavy mouthfeel significantly increased while fruity and floral aroma, black tea, sour and umami flavor, pureness, and softness decreased as roasting intensity increased. Principle component analysis showed the overall significant relationships between 23 sensory attributes and nine coffee samples under different processing and roasting conditions.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.3
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• pp.317-323
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• 1996

Physicochemical characteristics of Cassia tora seeds roasted at different conditions were investigated. Intact Cassia tora seeds were composed of water 11.6% crude protein 13.1%, crude fat 4.4%, curde fiber 13.8%, N-free extract 47.2% and ash 4.9%. Stacking volume ratio was increased generally by swelling, but soluble solids were decreased by rosating process L and B values decreased conspicuously as roasting temperature increase, but $\Delta$E value increased. The content of anthraquinones was 1, 200mg% in unroasted Cassia tora seeds, it increased as roasting time and temperature increase and reached maxium amount at 19$0^{\circ}C$-30min, 21$0^{\circ}C$-20min. and 23$0^{\circ}C$-10min. agter that it decreased remarkably. Optimum roasting condition of Cassia tora seeds was 21$0^{\circ}C$-20min.