• Korean Journal of Food Science and Technology
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• v.45 no.5
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• pp.657-660
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• 2013

The effects of roasting temperature and time on the antioxidant activities of Cassia tora L. were investigated. In comparison with raw seeds (7.15 mg TAE/g), roasted seeds contained a significantly higher total polyphenol content (p<0.05). However, seeds roasted at a higher temperature ($250^{\circ}C$) for 10 min showed a significantly lower total polyphenol content (2.30 mg TAE/g; p<0.05). The electron donating abilities of Cassia tora L. seeds increased with an increase in roasting time; further, seeds roasted for 5 min at lower temperatures showed higher electron donating abilities (80.61% at $175^{\circ}C$; 80.75% at $200^{\circ}C$) than did seeds roasted for 5 min at higher temperatures (76.26% at $225^{\circ}C$; 77.35% at $250^{\circ}C$). Seeds roasted at lower temperatures showed adequate L values, regardless of roasting time; by contrast, seeds roasted for 10 min at higher temperatures, showed markedly lower L values. Our results indicate that roasting temperature and time must be controlled to produce high-quality Cassia tora L. products.

• Korean Journal of Food Science and Technology
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• v.46 no.3
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• pp.390-393
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• 2014

The effects of roasting temperature and time on the antioxidant activities of tartary buckwheat were investigated. Compared to raw seeds (2.05 mg TAE/g), seeds roasted at $175^{\circ}C$ for 5 min showed significantly higher total polyphenol content (p<0.05), while those roasted at $250^{\circ}C$ for 10 min showed significantly lower total polyphenol content (2.77 and 2.56 mg TAE/g, respectively). The electron-donating abilities of tartary buckwheat seeds increased with an increase in the roasting time at lower temperatures (p<0.05). However, seeds roasted at a higher temperatures ($250^{\circ}C$) for 10 min showed significantly lower electron-donating abilities (p<0.05). Seeds roasted at $175^{\circ}C$ showed adequate L values, regardless of the roasting time. In contrast, seeds roasted for 10 min at $250^{\circ}C$, showed markedly lower L values. Our results suggest that the roasting temperature and time must be controlled to produce high-quality tartary buckwheat products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.647-654
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• 2000

Response surface methodology (RSM) was used for monitoring the changes in browning reaction and organoleptic quality of roasted Polygonatum roots under various of roasting conditions. Total free sugar decreased up to 13$0^{\circ}C$, but increased above 13 $0^{\circ}C$. The amounts of total free amino acids decreased in proportional to the roasting temperature and time. Theronine, glycine and serine decreased by about 91~94% under the roasting conditions. Browning color intensity of water extracts increased with the roasting time up to around 18 min, but decreased over 18 min. The optimum conditions based on overall palatability of the roasted Polygonatum roots were 13$0^{\circ}C$ and 15 to 25 min. Organoleptic qualities of the roasted samples showed higher correlations with the changes in free amino acids.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.768-772
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• 1995

The physico-chemical properties of hot-water extracts of dried and roasted Boxthorn(Lycii fructus) were investigated. The proximate composition of dried Boxthorn was 17.5% moisture, 5.4% ash, 14.7% lipid, 18.9% protein, 11.8% fiber and 31.7% carbohydrate. As the roasting temperature and time increased, water soluble solids, turbidity, titrable acidity and redness of the hot water extracts were increased, while the free sugar content was reduced. The linoleic acid of roasted Boxthorn decreased and palmitic acid increased at higher roasting temperature. The sensory properties of sweet odor, burnt odor, sour taste, burnt taste and tannic taste of the hot water extract were scored higher and sweet and roasted taste were lower as the roasting temperature and time increased.

• Culinary science and hospitality research
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• v.16 no.1
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• pp.1-12
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• 2010

This study analyzed the physical quality and sensory characteristics of Artemisia by experimenting the medicinal effect and functionality of Artemisia in roasting condition of temperature on 80, 110, and $230^{\circ}C$, roasting condition of time on 6 min, blanching condition($100^{\circ}C$) of time on 1 min, oven drying condition of $50^{\circ}C$, 5 min, and additive amounts of 0.1, 0.2, and 0.5% in order to make brown sauce. Its color values in roasting and blanching showed a little significant difference. Its sugar content when roasted at $110^{\circ}C$ and 0.5% of addition was the highest; in all groups, the more addition, the more sugar content. Spreadability in roasting with 0.5% of addition was increased and the group with 0.1% of addition was decreased in blanching, which showed a little significant difference. Its sensory characteristics showed high in 0.1, 0.2, 0.5% when blanched, roasted, and 0.1% when oven dried.

• Korean journal of food and cookery science
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• v.15 no.5
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• pp.490-499
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• 1999

The purpose of this study was to investigate the changes of taste components in the boiled beef brisket soup stock and shank soup stock by varying pretreatment, boiling temperature and time. Free amino acids and nucleotides color and sensory evaluation in each samples were analyzed. The results were obtained as follows : 1. The amount of free amino acids in the brisket soup stock pretreated by soaking and blanching showed a tendency to increase in proportion to boiling time. The amount of glutamic acid in the brisket soup stock was much in order of soaking > blanching > roasting pretreatment. While the amount of glutamic acid in the boiled soup stock samples pretreated by soaking and blanching was much more at low temperature than at high temperature, the glutamic acid contents in the boiled soup stock pretreated by roasting were large at high temperature. The amount of glutamic acid in pretreated by soaked soup stock showed the highest and recorded 8.73 mg% at 6 hour-low temperature-boiling. 2. The amount of free amino acids in the shank soup stock did not show any regular tendency and had few changes in quantity by the methods of pretreatment. Each amount of glutamic acid in the shank soup stock pretreated by soaking and blanching was the highest, when boiled for 3 hours at high temperature. The samples pretreated by roasting showed the highest record 2.49 mg%, when boiled for 6 hours at high temperature, but could not recognize any regular tendency in the case of boiling at low temperature. 3. The amount of nucleotides in the brisket soup stock generally showed increase in proportion to boiling time. The amount of 5'-IMP extracted from the brisket soup stock was much in order of blanching > soaking > roaking pretreatment, but few differences between blanching and soaking soup stock samples. The amount of 5'-IMP extracted from soup stock samples pretreated by soaking and blanching was high at low-boiling and by roasting at high-boiling. Each amount of 5'-IMP extracted from soup stocks pretreated by soaking(BSL) and blanching(BBL) was the highest at 6 hour-low-boiling(37.06 mg%), and 5 hours(38.37 mg%) respectively. The amount of 5'in the soup stock pretreated by roasting(BRH) showed the highest records at 6 hour-high-boiling(10.85 mg%). 4. The amount of 5'-IMP extracted from the shank soup stock preteated by soaking and blanching showed a tendency to decrease after 3 hours boiling irrelative of boiling temperature. The amount of 5'in the shank soup stock was much in order of soaking > blanching > roasting pretreatment and showed high at the boiling of high temperature. In the sample pretreated by roasting it showed the highst records when boiled for 6 hours at high temperature(1.55 mg%). 5. The L Value of the brisket soup stock pretreared by roasting at high temperature(BRH) was the lowest and the b value of it was the highest of all the brisket samples boiled for 6 hours. No differences were found in the Value of L, a, and b in shank soup stock by the methods of pretreatment and boiling temperature. 6. The sensory scores in color and flavor of the brisket soup stock showd that BRH was higher than the other samples, and the preference in taste and overall was the highest in BSH while it was the lowest in BRH. The preference in the all sensory characteristics of SSH was higher than any other shank soup stock, but did not show any significant difference statistically.

• Korean Journal of Medicinal Crop Science
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• v.27 no.2
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• pp.108-114
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• 2019

Background: Rutin is decomposed by rutin-degrading enzymes (RDE) during the processing of buckwheat groats, resulting in a decrease in rutin content and a further increase in the bitterness of processed products. Thus, the present study aimed to examine RDE activity in groats and various tissues of domestic buckwheat varieties and to develop a method to reduce the loss of rutin during the groat processing. Methods and Results: RDE activity and isozymes patterns were determined in Tartary and common buckwheat. RDE activity, measured by quercetin production rate, was 273 and $70{\mu}g/g$ fresh weight/min in mature Tartary and common buckwheat groats, respectively. A total of six RDE isozymes were detected in mature groats of Tartary buckwheat on a non-denaturing gel. In Tartary buckwheat groats, RDE activity decreased by approximately 81 or 71% with roasting or steaming for 5 min respectively. As the roasting or steaming time increased to 30 min, RDE activity decreased by over 95%. These results indicated that RDE was inactivated in groats by roasting or steaming. When untreated Tartary buckwheat groats were kneaded with powder, RDE was activated and the quercetin production rate increased by 62%. However, when roasted groats were kneaded with powder, the quercetin production rate decreased by 93%, mainly due mainly to inactivation of RDE, as indicated by a decrease in band intensities of the six isozymes. Conclusions: These results suggested that the loss of rutin, due to RDE activity during processing, may be reduced by 71 to 100% by roasting or steaming groats for 5 to 30 min, due in large part to the inactivation of RDE isozymes.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.637-644
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• 2013

This study was conducted to obtain the baseline data for fermented tea with King oyster (Pleurotus eryngii) mushroom mycelium as well as to investigate the possibility of development for deodeok processing products. For this research, the physicochemical properties and antioxidant activity for fermented tea were confirmed by different roasting temperatures and roasting times. The results of the physicochemical properties, browning, turbidity, reducing sugar, total polyphenol and total flavonoid contents, were increased with increasing roasting temperature and roasting time, whereas the pH was decreased. The results of the antioxidant activity test of fermented tea, DPPH radical-scavenging activity, FRAP and reducing power, were increased with increasing roasting temperature and roasting time. The preference of fermented tea was confirmed as being the highest when roasted at $180^{\circ}C$ for 30 min. Although fermented tea did not have a unique flavor of mushroom and burnt flavor, it had strong color, flavor and taste. For this reason, fermented tea production for high content of functional materials and high preference is possible by roasting at $180^{\circ}C$ for 30 min. As for the results of this study, the physical properties of fermented deodeok were relatively stable on high temperature exposure and furthermore, the development of a variety of foods will be possible because fermented deodeok has an antioxidant capacity.

• Korean Journal of Food Science and Technology
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• v.50 no.5
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• pp.464-473
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• 2018

The objective of the current study was to evaluate the effects of roasting methods on volatile flavor compounds of boricha using solvent-assisted flavor evaporation-gas chromatography (GC)-mass spectrometry and GC-olfactometry. The barley roasting methods tested were air roasting (AR), drum roasting (DR), and air/drum roasting (ADR). Twenty, twenty-one, and eighteen aroma-active compounds were detected in the products of AR, DR, and ADR, respectively. Guaiacol (smoky), 2-acetylpyrazine (almond-like), and furfuryl alcohol (burnt sugar-like) were detected as high intensity aroma-active compounds. Intensities of most aroma-active compounds produced by the DR method were higher. On the other hand, aroma intensities of phenols produced by the AR method, such as guaiacol and 2-methoxy-4-vinylphenol (curry-like), tended to be stronger. Aroma characteristics of phenols are not considered to be desirable for boricha. Although roasting time for DR was longer than that for AR, DR may be an effective barley roasting method for enhancing desirable aroma characteristics of boricha.

• 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.