• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.4
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• pp.483-488
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• 1998

In order to elucidate the effect of heme compounds on lipid oxidation in roasted and/or reheated mackerel and pacific saury, changes in myoglobin, metmyoglobin, total iron, nonheme iron and heme iron content were measured. Throughout the steps of roasting, heating and reheating, myoglobin content was decteased more rapidly roasted at $180^{\circ}C$ for 20 min in fillet samples than those roasted at $200^{\circ}C$ for 15 min or $220^{\circ}C$ for 10 min. When the skinless samples were roasted at $180^{\circ}C$ for 20 min, about $38\%$ of myoglobin in raw meat were remained. The skinless fillet roasted at the lower temperature resulted the higher level of metmyoglobin due to the reduced myoglobin. Regardless of roasted temperature and time, total iron content was retained the level of raw meat throughout processing. 2 times of nonheme iron content was noted in the skinless fillet samples roasted at $180^{\circ}C$ for 20 min. All samples, heme iron content was decreased much lower by roasted temperature and in absence of skin on fillet. It was decreased about $33\%$ when roasted at $180^{\circ}C$ for 20 min in the skinless fillet in case of pacific saury.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.4
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• pp.520-531
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• 2007

In this study, we found that the moisture content of black sesame seeds increased in proportion to steaming time, and it decreased in reverse proportion to the roasting temperature and time. The crude fat and crude ash contents were shown to be in the order of steamed black sesame>raw black sesame and roasted black sesame>raw black sesame, Crude protein decreased in reverse proportion to the steaming time, and more crude protein was found in the raw black sesame samples than in the roasted black sesame samples. The contents of sesamin, sesamolin, and total lignans were shown to be in the order of roasted black sesame>raw black sesame>steamed black sesame. In the steamed black sesame samples, sesamin showed its highest level with 20 minutes of treatment, and sesamolin showed its highest level with 15 minutes of treatment. In the roasted black sesame samples, sesamin, sesamolin, and total lignans showed their highest levels with 15 minutes of treatment at $100^{\circ}C$. The phenolic compound content increased in proportion to steaming time in the steamed samples, and reached a peak after 15 minutes of treatment at $100^{\circ}C$, and then decreased after 20 minutes. SOD-like activity reached a peak after 15 minutes of treatment, and in the roasted sample it reached a peak after 15 minutes of treatment, and then decreased after 20 minutes. SOD-like activity was comparatively lower than tocopherol and higher than sesamol. The intensity of electron donating ability, following 30 minute treatments, was shown to be highest in the steamed black sesame samples after 25 minutes of treatment, and next highest in the roasted black sesame samples after 15 minutes at $100^{\circ}C$. The electron donating ability was comparatively lower than tocopherol and sesamol. With regard to lecithin's antioxidant effects, the steamed samples showed a higher oxidation restriction rate in proportion to time, and the roasted samples showed the highest rate after 15 minutes of treatment, and then decreased after 20 minutes of treatment. for hydroxyl radical scavenging, similar scavenging activity to tocopherol, and comparatively higher scavenging activity than sesamol, was shown in all samples: all samples showed scavenging abilities of 90% or higher. In summary, this study applied three different treatment methods to black sesame to determine the optimum treatment conditions, and also examined the antioxidant effects and functional characteristics. The results showed that roasting can be used for other purposes than producing oil, and also suggested that methods other than roasting can be used in a variety of ways in cooking. Also, the different treatment methods can be applied in cooking in a variety of ways, to enhance functionality and preference.

• The Korean Journal of Food And Nutrition
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• v.30 no.6
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• pp.1149-1156
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• 2017

We investigated the quality characteristics and the antioxidant efficacy of roasted maize tea according to different moisture contents (9% to 14%) using the puffing system (PS) and the roasting system (RS). Compared with the RS, the PS caused higher turbidity (0.017 vs. 0.003 in PS-14% vs. RS-14%), brown color intensity (0.170 vs. 0.059 in PS-14% vs. RS-14%), a-values (0.20 vs. -0.44 in PS-14% vs. RS-14%), b-values (7.90 vs. 5.57 in PS-14% vs. RS-14%), and a lower L-value (19.67 vs. 21.03 in PS-14% vs. RS-14%). Total polyphenol and flavonoid contents of roasted maize tea were increased along with the moisture content and they were higher with the PS (polyphenol; 5.95 mg GAE/g, flavonoids; 1.27 CE/g in PS-14%) than with the RS (polyphenol; 5.39 mg GAE/g, flavonoids; 1.12 mg CE/g in RS-14%). The DPPH and ABTS radical scavenging effects of roasted maize tea were also increased along with the moisture content, and the scavenging efficacy was significantly higher with the PS (DPPH; 160 mg TE/100g, ABTS; 507 mg TE/100g in PS-14%) compared with the RS (DPPH; 120 mg TE/100g, ABTS; 362 mg TE/100g in RS-14%). The polyphenol levels were significantly correlated with turbidity, brown color intensity, and L, a, and b-values of the roasted maize tea. In addition, an increase of the total polyphenol content in roasted maize tea induced antioxidant activities. As a result, an increase in polyphenols during the roasting process induced antioxidant activities which could prevent damage from free radicals.

• Journal of the Mineralogical Society of Korea
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• v.26 no.1
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• pp.9-18
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• 2013

In order to optimize the gold leaching process from refractory sulfide concentrate, a chlorine-hypochlorite solution with varying concentrations and temperatures were applied to salt-roasted concentrate. The concentrate consisted of pyrite, chalcopyrite, and galena, which were turned into hematite through air-roasting at $750^{\circ}C$. Also these concentrates were changed into hematite and nantokite (CuCl)) through salt (NaCl)-roasting at $750^{\circ}C$. The results of the gold leaching experiments showed that the best gold leaching parameters were obtained when the hydrochloric acid-sodium hypochlorite mix was at a ratio of 1 : 2, the added concentration was 1.0 M concentration, the pulp density was 1.0%, and the leaching was done at a $60^{\circ}C$ leaching temperature. The leaching rate for gold was much greater in the roasted concentrate than in the raw concentrate. The leaching rate was greater in the salt-roasted concentrate than in the plain roasted concentrate too. From XRD analysis, quartz was found in the salt-roasted concentrate and in the solid residue from the chlorine-hypochlorite leaching solution at $60^{\circ}C$.

• Korean Journal of Medicinal Crop Science
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• v.11 no.5
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• pp.329-335
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• 2003

This study was carried out to investigate physiological activities of chicory root (Cichorium intybus L. var. sativus). The anti-hepatotoxic activity of roasted chicory was studied using primary cultured rat hepatocytes where cytotoxicity was induced by galactosamine. The water extract of roasted chicory did not induced of cytotoxicity in primary cultured rat hepatocytes. Treatment with 5 mM galactosamin for 5.0 hr showed maximum increase in activity of lactic dehydrogenase (LDH) released in the medium. The water extract of roasted chicory inhibited significantly and dose-dependently the release of LDH activity increased by galactosamine-induced cytotoxity. The antidiabetic activity of water extract of roasted chicory was examined in streptozotocin induced diabetic rats. The increased blood glucose level in the streptozotocin induced diabetic rats was significantly decreased by the administration of chicory extract (800 mg/kg). Chicory water extract (800 mg/kg) prevented weight losses in streptozotocin induced diabetic rats. The antimutagenic activities of chicory water extract were tested using Salmonella thyphimurium YG 1024 as tester strains and 2-aminofluorence as a potent carcinogen in the presence of S-9 mix. No mutagenic activities of the water extracts of roasted chicory were observed on all the tested strains at dose $10{\sim}5,000$ ${\mu}/g$ per plate. Water extract of roasted chicory did not inhibit the mutagencities of Salmonella thyphimurium YG 1024 induced by 2-aminofluorene.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.2
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• pp.255-261
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• 2013

This study investigated changes in the physicochemical characteristics and coffee flavors of coffee beans under different roasting conditions. Four different kinds of roasted coffees were analyzed using a headspace gas chromatographic technique. The moisture content and total acidity of roasted coffee decreased whereas the pH and weight loss (%) increased, as coffee beans were roasted at higher temperatures. The Hunter's color values of the roasted coffee (indicating L (lightness) and b (yellowness)) decreased as the roasting temperature of the coffee beans increased, but a (redness) value only increased with light roasting. We also noted that the color of the Arabica coffee was darker than that of the Robusta coffee. The aroma compounds, acetaldehyde, acetone, 2-methylfuran, 2-methylbutanol, 2-methylpyrazine, furfural, 2-propanone, furfuryl alcohol, 2,5-dimethylpyrazine and furfuryl acetate were mainly analyzed. A sensory evaluation of all light-roasted coffees had flavor and sourness and those of all medium-roasted coffees had heaviness and finishness.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.3
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• pp.332-341
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• 2007

The purpose of this study was to investigate the change of flavor compounds of freeze-dried garlic and garlic roasted with soybean oil and sesame oil. Freeze-dried garlic and ground raw garlic roasted with oils was prepared at $180^{\circ}C$ for 5 minutes. Volatile compounds of garlic samples were obtained by Likens-Nickerson distillation/solvent extraction and identified by GC and GC/MS. Sulfur compounds, methyl allyl sulfide, diallyl sulfide, methyl allyl disulfide, dimethyl trisulfide, diallyl disulfide, methyl allyl trisulfide and diallyl trisulfide were the major volatile in garlic flavor which was more than 98% of the total volatile compounds. The total amount of sulfur compounds in freeze-dried garlic roasted with soybean oil was decreased to 20% compare to that of garlic flavor; however, 10 pyrazines such as 2-methyl pyrazine, 2,6-dimethyl pyrazine, 2-ethyl-5-methyl pyrazin and 3-ethyl-2,5-dimethyl pyrazine which were not originated from both freeze-dried garlic and soybean oil were identified. They might be generated from thermal interactions of sugars and nonvolatile flavor precursors of garlic. In freeze-dried garlic roasted with sesame oil, the amount of diallyl sulfide, methyl allyl disulfide, dimethyl trisulfide increased whereas diallyl disulfide completely disappeared. The amount of two cyclic compounds 3,4-dihydro-3-vinyl-1,2-dithiin and 2-vinyl-4H-1,3-dithiin, which were artifacts from allicin, increased in roasted garlic with sesame oil.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.938-944
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• 1999

Response surface methodology (RSM) was used for monitoring the changes of Hunter's color and organoleptic colors of roasted doraji tea with variations in threonine concentration of soaking solution and roasting condition. In soaking and roasting processes based on the central composite design with variations in threonine concentration of soaking solution, roasting temperature and roasting time, coefficients of determinations $(R^{2})$ of the models were above 0.87 (p<0.05) in Hunter's color parameters and organoleptic color. Hunter's color L value of roasted doragi tea was maximized in 0.09% threonine concentration of soaking solution, $142.37^{\circ}C$ and 21.94 min in roasting condition. Hunter's color a value of roasted doragi tea was maximized in 1.24% threonine concentration of soaking solution, $154.01^{\circ}C$ and 28.59 min in roasting condition, minimized in 1.67% threonine concentration of soaking solution, $137.61^{\circ}C$ and 24.62 min in roasting condition, Hunter's color b value of roasted doragi tea was maximized in 1.10% threonine concentration of soaking solution, $154.72^{\circ}C$ and 27.12 min in roasting condition. The maximum quality of organoleptic color of roasted doragi tea was soaked in 1.25% threonine concentration, and roasted at $141.81^{\circ}C$ for 34.14 min.

• The Korean Journal of Food And Nutrition
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• v.31 no.1
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• pp.149-159
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• 2018

The change of quality and physicochemical characteristics of mung-bean flours after germination and roasting treatment were evaluated. The moisture content of the roasted mung-bean flours decreased significantly according to the roasting temperatures and times, and the crude ash, protein and fat contents increased. The lightness of the roasted mung-bean flours significantly decreased, and the redness and yellowness increased. The water binding capacity of the roasted mung-bean flours without and with germination were 151.71 and 192.77% at $240^{\circ}C$ for 20 min, respectively. The water solubility index and swelling power decreased with an increase in roasting temperatures and times. The phenolic compounds and radical scavenging activity of the roasted mung-bean flours increased with an increase in the roasting temperatures and times. The total polyphenol contents of the roasted mung-bean flours without and with germination were 4.81~7.71 and 4.22~5.63 mg GAE/g, and the total flavonoid contents were 2.46~3.05 and 2.45~2.87 mg CE/g, respectively. The DPPH radical scavenging activity of the roasted mung-bean flours, without and with germination, were 106.83~376.08 and 174.41~346.70 mg TE/100 g, and the ABTS radical scavenging activity was 251.67~534.31 and 274.39~430.02 mg TE/100 g, respectively. As a result, it is necessary to set quality standards for each application considering the quality and antioxidant properties of the roasted mung-bean flours.

• Korean Journal of Food Science and Technology
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• v.32 no.3
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• pp.507-512
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• 2000

The headspace flavors of roasted tea, prepared with steamed and nonsteamed polygonatum roots, were absorbed in solid-phase microextraction(SPME) fiber coated with $65\;{\mu}m$ of carbowax/divinylbenzene(CW/DVB) and analysed by GC-MS. The absorption conditions of SPME fiber for equilibrated headspace were selected as $60^{\circ}C$ and 30 min. In a comparison for both samples roasted at $130^{\circ}C$ for 15 min, gas chromatograms showed a similar pattern in overall profiles between steamed and nonsteamed samples before roasting, but some differences were observed in peak characteristics. From 40 separated peaks, 25 compounds were identified with both GC-MS and retention time comparison. The pyrazines including 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one, 2,5-dimethyl-4-hydroxy-3(2H)-furanone, 2-acetyl-1-pyrroline, etc. were higher in their contents in nonsteamed-roasted sample than steamed-roasted one. In particular, steamed-roasted polygonatum showed higher contents of acetic acid(8.17%) and hexanoic acid(5.43%) than the corresponding compounds of nonsteamed-roasted one, 2.40% and 2.00%.