• Food Science and Preservation
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• v.13 no.2
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• pp.119-124
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• 2006

This study was conducted to optimize roasting process of Job's tears for utilization as food Optimal condition for masting was investigated with changes in temperature and time by response surface methodology. The qualities of water extract such as browning degree, polyphenol and DPPH radical scavenging ability were affected more by roasting temperature than time. The values increased with temperature and time proportionally. The response variables were more significant with temperature than time and the established polynomial model was suitable (P>0.05) model by Lack-of-Fit analysis. Optimal roasting conditions with the limit of $0.2{\sim}0.3$ browning degree, $2.0{\sim}2.5{\mu}g/mL$ polyphenol, $30{\sim}40%$ scavenging ability and $0{\sim}100$ hue angle were $215^{\circ}C$ and 32 min.

• 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.

• Journal of Environmental Science International
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• v.23 no.10
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• pp.1763-1773
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• 2014

It is known that mackerel and pork belly release a strong odor in the process of roasting. We evaluated a dilution factor of odor arising during roasting mackerel or pork belly and the relative odor strength using several cooking tools and analyzed compounds causing odors with gas chromatograph/mass detector. Roasting pans used were grill with lid, electric grill without lid and general roasting pan, and a grill with lid can attach the activated carbon charcoal deodorant at the inside of lid. And all electric grills have a drip tray under the heater. We investigated characteristics of odor emission depending on the presence of water and deodorants in these cooking tools. Study has shown that roasting mackerel produces approximately 36 time more odors than roasting pork belly, and the reduced odor emission when roast with water. And it shows the reduced deodorant effect when cooked with water after attaching activated carbon charcoal in the cooking pan. Major odor causing compounds arising when cooking mackerel and pork belly were aldehydes with high boiling point such as octyl aldehyde with a low odor threshold value.

• Korean Journal of Plant Resources
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• v.31 no.6
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• pp.704-713
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• 2018

Roasting has revealed coffee's potentials as a good source of bioactive compounds. This study was done to investigate the quantitative presence and activity of bioactive compounds including caffeine, chlorogenic acid (CGA), amino acids, and antioxidant capacity on Coffea arabica L. (Guatemala finca San Sebastian) and C. robusta L. (India Azad Hind). Analysis was performed on Green Bean (GB) Medium-Light (ML), Medium (ME) and Medium-Dark (MD) samples of both varieties. From the results, caffeine content was highest in ME samples of both varieties. GB samples of both varieties had high CGA content which decreased after increasing roasting time and temperature. Most amino acids in GB samples was highest, however, glutamic acid, valine, tyrosine, isoleucine, leucine and phenylalanine had highest quantitative increase in ME samples for both varieties. $IC_{50}$ of DPPH and ABTS radical scavenging activity was highest in ML samples of both varieties. $IC_{50}$ of reducing power and total phenolic content was highest in GB sample of both varieties but decreased after increasing roasting conditions. Generally Robusta had the highest quantity of bioactive compounds and antioxidant activity. From this study, the optimal roasting condition for coffee is ME above which there is a significant reduction of bioactive compounds and antioxidant activity.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.171-175
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• 1999

Changes in physicochemical characteristics of steamed rice during roasting were investigated. Steamed rice was roasted at various temperature $(150{\sim}220^{\circ}C)$ for various time $(10{\sim}30min)$. L and b Hunter color values of steamed rice were decreased, but E value was increased by roasting. The water absorption index and the water solubility index were gradually with increasing roasting temperature and time up to $200^{\circ}C$ for 30min, but decreased at $220^{\circ}C$ for 20min. The yield of water extracts from steamed and roasted rice were sharply increased with increasing roasting temperature and time, however, precipitates and turbidity were decreased. The content of reducing sugar was slowly increased up to $200^{\circ}C$ and remarkably increased above it. The contents of amino acids were decreased by roasting. Among them, cystine, lysine and serin were significantly reduced with increasing roasting temperature.

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.575-582
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• 1989

An investigation was carried out to improve the quality and yield of barley tea(water extracts) by modifying the roasting method. The modified methods employed were crushing the barley into 4-10 parts and soaking in water at room temperature for 20 minutes followed by roasting (light brown or dark brown) at $250^{\circ}C$ before boiling with water. The varieties of barley used for this study were Ol-bori(with hulls) and Youngsan-bori(without hulls) and the qualities measured were the physical, chemical and sensory characteristics of roasted barley and its extracts. The results showed that the higher solid yields in barley tea was obtained with an increase in soaking and roasting time. The solid yields increased rapidly with extraction time in boiling water until 30 minutes and then slowed down thereafter. However the intrinsic viscosity of barley tea was reduced by increase in soaking and roasting time. The color of barley tea expressed as Hunter L, a, b values showed that lower L value and higher a and b values were measured for those prepared without soaking and with more extensive roasting. Organoleptic evaluation clearly showed that the sensory quality of barley tea was significantly improved in intensity of odor and taste by crushing, soaking and dark brown roasting.

• The Korean Journal of Food And Nutrition
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• v.35 no.5
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• pp.302-312
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• 2022

The purpose of this study was to investigate the Maillard reaction-related physicochemical properties of three maize varieties (Kwangpyeongok, Sinhwangok2ho and Gangdaok) after roasting them for different times (0, 15, 25, 40, and 55 minutes). The Maillard reaction is a non-enzymatic browning reaction involving reducing sugars and amino compounds. The content of reducing sugar, the causative agent of the Maillard reaction, decreased as roasting time increased. Gangdaok showed the lowest reducing sugar content of 1.04 mg/g after 55 minutes of roasting. In the elapsed roasting time, chromaticity 'L' and 'b' values decreased. At 55 minutes of roasting, wherein the Maillard reaction occurred most actively, Gangdaok showed the lowest 'L' value of 56.37 and the highest 'a' value of 7.60. Gangdaok had superior conditions for inducing the Maillard reaction compared to other varieties, and it is consider that 'flint-type', an endosperm characteristic, may have been the influencing agent. This study detected a total of 52 types of volatile aroma compounds (VACs), of which 28 were produced after roasting. Of the total VACs detected, 2-Formyl-5-methylfuran and 2-Furancarboxaldehyde accounted for 43.8~45.5% and have been confirmed to be the major VACs present in roasted maize. Most of the correlations between the Maillard reaction-related characteristics showed high correlation coefficients.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.1
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• pp.35-42
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• 1998

Whole faba beans (WFB) were dry roasted at different temperatures (110, 130, $150^{\circ}C$) for 15, 30, 45 minutes to determine the optimal heating conditions of time and temperature to increase nutritional value. Ruminant degradation characteristics of crude protein (CP) of WFB were determined by the nylon bag incubation technique in dairy cows fed 60% hay and 40% concentrate. Measured characteristics of crude protein (CP) were soluble (washable) fraction (S), undegradable fraction (U), lag time (T0), potentially degradable fraction (D) and the rate of degradation (Kd) of insoluble but degradable fraction. Based on measured characteristics, percentage bypass crude protein (%BCP) and bypass crude protein (BCP in g/kg) were calculated. Degradability of CP was reduced by dry roasting (p < 0.01). S was reduced rapidly with increasing time and temperature, from 49.0% in the raw WFB (RWFB) to 26.3% in $150^{\circ}C/45$ min. D varied from 50.7% in RWFB to 73.7% in $150^{\circ}C/45^{\prime}$. U varied from 0% in $130^{\circ}C/45^{\prime}$, $150^{\circ}/30^{\prime}$ and $150^{\circ}/45^{\prime}$ to 0.66% in $110^{\circ}/45^{\prime}$ (0.24% for the RWFB). Lag time (T0) varied from 1.58 h in $130^{\circ}C/30^{\prime}$ to 2.40 h in $150^{\circ}C/45^{\prime}$ (1.87 h for RWFB). Kd varied from 24.2% in the $110^{\circ}C/30^{\prime}$ to 4.3% in $150^{\circ}C/45^{\prime}$ (21.4% for the RWFB). Kd was significantly reduced with time and temperature. All these effects resulted in increasing % BCP from 8.9% in the $110^{\circ}C/45^{\prime}$, 11.3% in the RWFB to 43.1% in the $150^{\circ}C/45$. Therefore BCP increased from 31.3 and 39.9 to 148.4 g/kg respectively. Both %BCP and BCP at $150^{\circ}C/45$ increased nearly 4 times over the raw faba beans. The effects of dry roasting temperature and time on %BCP and BCP seemed to be linear up to the highest values tested. Therefore no optimal dry roasting conditions of time and temperature could be determined at this stage. It was concluded that dry roasting was effective in shifting crude protein degradation from rumen to intestine to reduce unnecessary nitrogen (N) loss in the rumen. To determine the optimal treatment, the digestibility of each treatment should be measured in the next trial using mobile bags technique.

• Korean journal of food and cookery science
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• v.30 no.5
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• pp.526-530
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• 2014

The effect of roasting on particle size distribution, water-holding capacity, and viscosity of sunsik was investigated in this study using non-roasted one as control. Roasting increased the size of particles in sunsik, in particular, particles larger than $1{\mu}m$ in diameter, indicating that roasted sunsik is likely to sediment faster, thereby decreasing the time to maintain dispersibility when mixing with water. Roasting also increased the water-holding capacity of sunsik, indicating that polymerization occurred greater than a pyrolysis during roasting, leading to increased viscosity in roasted sunsik. These results indicate that the roasting affected the dispersibility and viscosity of sunsik by increasing particle size and water-holding capacity, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.675-681
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• 2014

This study was conducted to determine the optimal roasting temperature (90, 100, 110, and 120; fixed time of 20 minutes) of small black coffee beans under various roasting conditions. The roasting temperature range and fixed time were the same as our preceding study. After roasting, the general composition, isoflavone contents, and antioxidant activities were measured. As the results of the proximate composition analysis of small black beans according to roasting conditions, only moisture decreased among them, whereas other general compositions were not affected. The DPPH and ABTS radical scavenging activities were the highest at a roasting temperature of $120^{\circ}C$. Total polyphenol and total flavonoid contents were also highest at $120^{\circ}C$. Isoflavone contents showed a positive correlation with DPPH and ABTS radical scavenging activities, as well as total phenol and flavonoid contents. These results suggest that the optimal roasting conditions of small black beans were determined to be $120^{\circ}C$ for 20 minutes.