• The Korean Journal of Food And Nutrition
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• v.29 no.1
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• pp.1-11
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• 2016

To enhance the physiological activities of roasted coffee (RC), 30 kinds of green coffee beans (GCB) with different cultivating areas and varieties were fermented with Monascus ruber mycelium (MR) by solid-state culture. After the dried MR-fermented GCB was subjected medium roasting, each RC was extracted with hot-water. Among the hot-water extracts, the highest yield was the hot-water extract of RC from MR-fermented Indonesia Mandheling GCB (15.5%). However, the hot-water extract of RC from MR-fermented Ethiopia Sidamo GCB showed significantly higher polyphenolic contents (3.08 mg GAE/100 mg) and ABTS free radical scavenging activity (25.41 mg AEAC/100 mg). Meanwhile, the hot-water extract of RC from MR-fermented Vietnam Robusta GCB showed not only the effective inhibition of $TNF-{\alpha}$ level (73.7% inhibition of LPS-stimulated control) from LPS-stimulated RAW 264.7 cells but also significant inhibition of lipogenesis (63.5% inhibition of lipid differentiation control) in 3T3-L1 pre-adipose cells. In conclusion, these results suggest that roasted coffees from Ethiopia Sidamo and Vietnam Robusta green coffee beans fermented with Monascus ruber mycelium using solid-state culture could have industrial applications as functional coffee beverages.

• 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.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.

• The Korean Journal of Food And Nutrition
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• v.29 no.2
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• pp.178-185
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• 2016

This study was designed to develop and to qualify a coffee alternative beverage using a mixture of coffee beans and roasted black beans (Rhynchosia nulubilis). Therefore, the total isoflavone content (TIC), total phenol content (TPC), antioxidant activity, anti-inflammatory activity, NFATc1 (Nuclear factor of activated T-cells c1) expression in RANKL (receptor activator of nuclear factor kappa-B ligand)-stimulated RAW264.7 cells and sensory evaluation were measured for 5 different Cb (coffee bean)-RoS (roasted seomoktae) mixture extracts (Cb100RoS0, Cb75RoS25, Cb50RoS50, Cb25RoS75, and Cb0RoS100). Cb0RoS100 had the highest TIC ($516.83{\pm}36.61mg/100g$) and TPC ($18.11{\pm}1.77mg$ TAE/100 g) along with the highest antioxidant activity as measured by DPPH radical scavenging activity ($73.55{\pm}8.11%$) and ABTS radical scavenging activity ($63.27{\pm}7.27%$). Also, Cb0RoS100 showed the highest anti-inflammatory activity as measured by NO production ($13.57{\pm}2.21{\mu}M$) and PGE2 production ($3.25{\pm}0.21ng/mL$). The more the RoS ratio was increased in the mixtures of Cb-RoS, the more the NFATc1 protein expression was decreased in RANKL-stimulated RAW264.7 cells. In case of sensory evaluation, Cb50RoS50 had the highest scores for flavor, delicate flavor and overall quality, which were similar to those in Cb alone (Cb100RoS0). We suggest that the use of RoS replacement instead of Cb in/as a coffee alternative beverage may help to reduce the risk of caffeine-related bone loss and/or bone disease by effectively blocking NFATc1 expression in RANKL-stimulated RAW264.7 cells compared with Cb alone.

• Korean Journal of Food Science and Technology
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• v.49 no.5
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• pp.474-479
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• 2017

Five types of coffee bean, which are usually imported and consumed in Korea, were roasted at $250^{\circ}C$ for 15 min and extracted by using a filter coffee machine. The physicochemical properties, functional components, and radical scavenging activity of coffee bean extracts were investigated. The pH of extract was the highest among the extracts and the soluble solid contents of extracts were $0.9-1.0^{\circ}Bx$. The acidity of the extracts was in the range from 0.46-0.55%, which was not significantly different from the control. Indonesian coffee bean extract showed the highest brown color intensity and contained the highest amounts of caffeine and chlorogenic acid. The highest total polyphenol content was found in Kenyan coffee bean extract. Coffee bean extracts from Indonesia and Kenya showed significantly higher radical scavenging activities than the other extracts. This study showed that coffee bean extracts from Indonesia and Kenya contained a large number of bioactive compounds and high antioxidant activity.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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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.

• Food Science and Preservation
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• v.23 no.5
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• pp.638-644
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• 2016

To examine the utilization possibility of defective coffee beans, non-defective and defective coffee bean were compared by means of its physiochemical properties and antioxidant capacities measured by DPPH radical scavenging activity, FRAP assay, total phenol contents, functional component (trigonelline, caffeine, chlorogenic acid) contents. After roasting process, pH and soluble solid contents of coffee extracts decreased; $L^*$ value decreased while $a^*$ and $b^*$ values increased. DPPH radical scavenging activities of defective green bean extracts were higher than that of non-defective green bean extracts. Immature green bean extract showed the highest radical scavenging activity. In FRAP assay, green bean extracts ranged from 15.28~21.80 mM TE which was higher than roasted bean extracts which showed 14.81~16.38 mM TE. Total phenol contents of green bean extracts ranged 191.06~256.25 mg% GAE which was higher than that of roasted bean extracts showed 161.91~173.44 mg% GAE. The contents of trigonelline, caffeine, chlorogenic acid in immature green bean extract were the highest, which showed 895.20 mg/L, 825.85 mg/L and 3,836.94 mg/L respectively. Each contents were decreased after roasting process. Results of this study suggest that defective coffee bean can be used as a functional food material.

• Journal of Ginseng Research
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• v.34 no.1
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• pp.1-7
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• 2010

The quality attributes of coffee treated with different concentrations of white ginseng extract were examined. Increased concentration of white ginseng extract was associated with higher color values (Hunter L. a, b scale). The crude saponin contents of untreated roasted coffee beans (control) and those coated with $5^{\circ}$ Brix (WGC-1) and $20^{\circ}$ Brix white ginseng extract (WGC-2) were 8.29%, 8.74%, and 8.93%, respectively. The total ginsenoside contents of WGC-1 and WGC-2 were 0.3 mg/g and 0.6 mg/g, respectively. In the case of major ginsenosides, the contents of ginsenosides $Rg_1,\;Rg_2,\;Rb_1,\;Rb_2,\;Rg_2,\;Rh_1$, and $Rg_3$ increased directly with the concentration of white ginseng extract. Total sugar and acidic polysaccharide contents also increased directly with the concentration of white ginseng extract. The coffee beans coated with ginseng extract scored significantly higher ginseng taste scores than the control (p<0.005) in sensory evaluation. In terms of coffee taste, WGC-2 had significantly lower scores than the commercial coffee bean. In the consumer sensory evaluation, overall preference did not differ significantly among the treatments.

• Food Science and Preservation
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• v.22 no.5
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• pp.690-698
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• 2015

Effects of roasting on physical (weight, volume, density and color) and chemical properties (total phenol, caffeine, chlorogenic acid and antioxidant properties) of three Arabica coffee beans (Brazil Bourbon, Indonesia Mandheling and Kenya Tatu) were investigated. A steady weight loss, volume increase, and bean density decrease were observed during the roasting process. The $L^*$, $a^*$, and $b^*$ values tended to decrease as the roasting temperature and time increased. Caffeine level was approximately 0.73% in green beans, and increased to 40-67% for darker roasts. Green beans contained the highest chlorogenic acid content, which decreased as the roasting temperature and time increased. The light- and medium-roasted coffee showed the highest total phenolol contents. The antioxidant activities were measured using DPPH and ABTS. The light-roasted coffee beans showed the highest antioxidant activities, and an approximately 36-51% loss in antioxidant activity was observed after further roasting. The flavor patterns of roasted coffee beans were analyzed using an electronic nose system based on gas chromatography. This analysis demonstrated that an electronic nose system can be applied to identify the green bean variety and the degree of roasting.

• Journal of Food Hygiene and Safety
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• v.30 no.3
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• pp.236-241
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• 2015

This study was performed to survey and evaluate the contents of pH, total acidity, caffeine, harmful metals (Pb, Cd) and total polyphenol in coffee extraction. In total, coffee bean. Total fifty coffee samples were analysed. A 5 g portion of roasted ground coffee samples were extracted in coffee-maker with 100 mL of distilled water and the extraction were used in all experiments. The pH range was 4.72~5.25 (mean value = 4.99). According to increase of the roasting temperature, the pH were shown a tendency to increase. The contents of total acidity was 0.72~2.25% (mean value = 1.59%). According to increase of the roasting temperature, the contents of total acidity were shown a tendency to decrease. The contents of harmful metals (Pb, Cd) in coffee extractions were determined by ICP. The average contents of Pb and Cd were 0.0112 and 0.0011 mg/kg, respectively. The contents of caffeine in coffee extractions were determined by HPLC, the range of detection was 0.51~20.28 mg/mL (mean value = 12.29 mg/mL). According to increase of the roasting temperature, the contents of caffeine were shown a tendency to increase. The contents of total polyphenol in coffee extractions were determined by spectrophotometer, the range of detection was 18.88~43.90 mg/mL (mean value = 31.94 mg/mL). According to increase of the roasting temperature, the contents of total polypenol were shown a tendency to decrease.