• KSBB Journal
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• v.20 no.3
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• pp.210-214
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• 2005

The characteristics of sesame oil containing one of natural antioxidant, ' $\gamma$-tocopherol', were studied with the supercritical $CO_2$ extraction. Although $\gamma$-tocopherol has a lower vitamin E value in biological systems than $\alpha$-tocopherol, it is a more potent antioxidant with in oils. For the research of various factors influence to the $\gamma$-tocopherol contents increment, we have checked roasting time and temperature, as well as pressure, temperature and flow rate of supercritical fluid. As a result, we found that the $\gamma$-tocopherol content was maintained constant under the condition of roasting temperature over $200^{\circ}C$. With the longer roasting time, $\gamma$-tocopherol content was increased. Except 250 bar, the $\gamma$-tocopherol content was maintained constant under the condition of the various pressure of supercritical fluid. But $\gamma$-tocopherol content was increased with lower flow rate of supercritical fluid from 1 $m{\ell}$/L to 3 $m{\ell}$/L. When the extraction performance with the supercritical fluid was compared to the conventional compressed extraction, $\gamma$-tocopherol content was increased up to 1.6 times.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.5
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• pp.639-645
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• 2017

Differences in bioactive compounds and antioxidant activities of aronia leaf (AL) extracts according to manufacturing conditions such as different number of pan-roasting and different temperatures were investigated. Both total polyphenolic compounds and total flavonoids contents were the highest in six time-pan-roasted AL tea extract ($37.96{\pm}0.48mg$ catechin equivalent/g and $19.96{\pm}0.44mg$ quercetin equivalent/g, respectively) among four tea samples. Antioxidative activities were also the highest in six time-pan-roasted AL tea extract with $IC_{50}$ 0.43 mg/mL and $IC_{50}$ 0.27 mg/mL based on DPPH and ABTS radical scavenging activities, respectively. HPLC analysis revealed that AL tea infusion did not have caffeine regardless of manufacturing conditions, whereas green tea infusion had 3.8 mg/g caffeine. Results demonstrated that AL tea can be expected as caffeine free leaf tea containing antioxidant benefits. Moreover, specific pan-roasting conditions of AL tea would be very important for its functional and sensory attributes.

• Korean Journal of Food Science and Technology
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• v.53 no.1
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• pp.78-84
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• 2021

As a calorie supplement for the elderly, functional beverages based on black sesame were prepared with different roasting times (0, 10, 15, and 20 min for R-0, R-10, R-15, and R-20, respectively), and their properties were compared. The total calorie content of the beverage was adjusted to match that of half a meal to meet the nutritional requirements of the elderly. The suspension stability of all samples was maintained for 5 day by the addition of xanthan gum. Regarding the color of the beverage, L* and a* values decreased, whereas b* increased with the increase in black sesame roasting time. Among the samples, the total lignan content did not change, except for R-20, which showed a significantly lower value than the others. Total polyphenol content significantly increased with roasting time, reaching the maximum value in R-15 and R-20; however, the free radical scavenging effect decreased for R-20. Based on the results of the sensory test, R-15 was the most acceptable for customized beverages.

• Resources Recycling
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• v.18 no.5
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• pp.37-43
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• 2009

The demand for rhenium has considerably increased recently owing to the large-scale consumption in industries and the price of rhenium has increased owing to the lack of supply and its availability. The dust from the roasting of molybdenite was employed to investigate the leaching behavior of rhenium and molybdenum. Leaching experiments were done by varying optimum parameters, such as reaction time, NaOH concentration and leaching temperature. The optimum leaching condition was found to be $4\;mol{\cdot}L^{-1}$ NaOH, 2 hours leaching time, $100\;g{\cdot}L^{-1}$ solid/liquid ratio, $80^{\circ}C$ temperature, and 250 rpm. At this condition, leaching percentage of rhenium and molybdenum was 86.1% and 88.6%, respectively.

• Korean journal of food and cookery science
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• v.20 no.4
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• pp.342-351
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• 2004

Rice flour was roasted at different temperatures and times and tarakjuk was made from these roasted rice flours. Chemical composition, in vitro starch digestibility (IVSD) and protein digestibility (IVPD) of the roasted rice flours and tarakjuk were determined. Changes in quality characteristics such as pH, viscosity, IVSD and IVPD of tarakjuk during refrigerated storage were also investigated. For roasted rice non, the protein content ranged from 6.52∼7.13% on a dry basis, while for tarakjuk, the range was 3.74 ∼4.0%. On the other hand, the Ca level of tarakjuk ranged from 1,278.36∼1,340.87 ppm. Rice flours showed decreasing IVSD and increasing IVPD on roasting at 145$^{\circ}C$ and 165$^{\circ}C$, whereas they showed increasing IVSD and decreasing IVPD at 185$^{\circ}C$, respectively. Roasting also influenced the pH, viscosity, IVSD md IVPD of tarakjuk made from these roasted rice flours. As the roasting temperature and time increased, tarakjuk showed lower pH and viscosity, however it showed higher IVSD and IVPD. The pH of tarakjuk, except that of control, decreased with storage, whereas viscosity increased significantly. IVSD decreased up to 4 days of storage, after which it increased again until 14 days of storage. On the other hand IVPD increased up to 7 days of storage, but there was no additional significant increase after 14 days of storage. These results suggest that depending on the nutritional purpose, appropriate conditions for roasting of rice flour and storage of tarakjuk may be recommended for the commercialization of tarakjuk.

• Culinary science and hospitality research
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• v.21 no.2
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• pp.1-10
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• 2015

The purpose of this study was to establish the critical limit of CCP (Critical Control Point) of a HACCP (Hazard Analysis Critical Control Point) system used in the production of seasoned laver products. The hazard analysis examined microbial evaluations and developed a HACCP management plan for the heating process. The results were determined to be capable of reducing the biological element of CCP via the secondary roasting process. This study examined general bacteria and pathogenic microorganisms such as Escherichia coli, Staphylococcus aureus, Salmonella spp., Listeria monocytogenes, Vibrio parahaemolyticus, and Bacillus cereus at temperatures ranging from $170^{\circ}C$ to $230^{\circ}C$ and for 3.0 to 5.5 seconds at a time. Before the secondary roasting process, pathogenic microorganisms were all negative, although the presence of general bacteria was still detected. General bacteria was reduced to $1.0{\times}10CFU/g$ after the temperature was set at $230^{\circ}C$ for a period of 5.5 seconds. In conclusion, it suggested that a HACCP plan was necessary for management standard and systematic approach in the establishment of critical limit, problem resolution, verification method, education, and records management through a secondary roasting process.

• Food Science and Preservation
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• v.24 no.3
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• pp.440-445
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• 2017

We evaluated the antioxidative activity of extracts of P. lobata root depending on roasting conditions. P. lobata roots were roasted at three different temperature at $150^{\circ}C$, $200^{\circ}C$, and $250^{\circ}C$ and three different time at 10 min, 20 min, and 30 min respectively. Roasted P. lobata root was extracted using water at $85^{\circ}C$ for 6 h and filtered using filter paper, followed by then evaporated ($12{\pm}0.3^{\circ}Brix$) and freeze-dried. The concentration of maker compound puerarin was determined using a high performance liquid chromatography system. 2 phenolic compounds, flavonoid contents, and antioxidant activities of the extract powder were evaluated. Puerarin contents, Phenolic compounds, and flavonoid contents of roasted P. lobata root were higher than those of unroasted P. lobata root. The results of DPPH and ABTS showed that roasted P. lobata root possessed higher antioxidant activity than unroasted P. lobata root. This study suggested that roasting process could be applied to P. lobata root in order to achieve its high quality and functionality.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.30 no.1
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• pp.75-86
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• 2020

Objectives: In this study, we assessed respiratory hazards in the working environment as the work-relatedness of occupational diseases were examined. Methods: The subjects of the study were three Korean meat roasting restaurants, one Chinese restaurant, and two cafeterias. Measurement items were total dust, respirable dust, fine dust (PM_2.5), PAHs, TVOCs, temperature, humidity, carbon monoxide, carbon dioxide, and nitrogen dioxide. Results: The concentration of total dust and respiratory dust in the restaurant was low. Most PAHs were undetectable, but some Napthalene and Acenaphthylene was detected. Thirteen kinds of PAHs were detected in one sample of roasted meat, and Benzo(a)pyrene was 1.496 ㎍/㎥. PM_2.5, TVOCs, CO, and CO₂ were instantaneously high, but the average concentration was low. NO₂ was not detected. Conclusions: The results show that harmful substances such as PM_2.5, PAHs, CO, and TVOCs were generated in the air in the catering industry. When roasting meat, Benzo(a)pyrene, a carcinogen related to lung cancer, was generated among PAHs. Lung cancer can occur when working for a long time in such a working environment. Therefore, it is necessary to improve the working environment for the health of restaurant workers, and it is necessary to evaluate the concentration of harmful substances by cooking method through further research.

• 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.

• Food Science and Preservation
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• v.14 no.6
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• pp.605-610
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• 2007

The quality of guava (Psidium guajava L.) leaves processed using different methods, such as fermentation, steaming, and roasting were investigated. The total phenolics content was highest in the roasted guava leaves. While tyrosinase inhibition and electron donating abilities were highest in steamed guava leaves. The overall palatability showed higher scores in both fermented and steamed guava leaves compared to roasted ones. Upon blanching and steaming of guava leaves, the total phenolics content, tyrosinase inhibition ability, and electron donating ability decreased as the treatment time increased. The overall quality properties were significantly higher in steamed than the blanched samples. The sensory scores, however, were low mainly due to the astringent taste of guava leaves. Thus, it was found that the removal or masking of the astringent taste of guava leaves is of primary concern for their further use.