• The Korean Journal of Food And Nutrition
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• v.20 no.1
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• pp.14-19
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• 2007

Caffeine is one of the most well known stimulants which can potentially increase mental performance, release fatigue and decrease depression. Green beans from different soils and climates contain different levels of caffeine, and as well as extracted coffee with different roasting and extracting methods. An investigation looking at pH, acidity, extractable solid and caffeine contents was assessed according to roasting and extracting conditions of various coffee beans. Brazilian coffee beans did not show much variation in pH with respect to roasting and extracting temperature, however, acidity increased in low roasting and extracting temperatures. This was however most prominently observed in Ethiopian and Indonesian coffee beans. The large expansion of coffee bean cells renders them highly porous to the passage of water, consequently extracted solids were found to increase with increasing temperature. This was especially apparent in Columbian coffee which had the highest extracted solids. The amount of caffeine extracted from coffee beans also increased with the higher temperature extraction. The Indonesian and Vietnam robusta coffee varieties showed the highest caffeine content.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.4
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• pp.365-377
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• 2017

The objective of this study was to investigate the sensory quality characteristics of coffee under various processing and roasting conditions of green beans. Colombia green bean samples were obtained from three processing methods: natural, pulped-natural, and washed methods. The green beans were roasted differently according to Agtron number: light (Agrton #65), medium (Agtron #55), and dark (Agtron #45). Moisture content, density, color value, pH, and total dissolved solid contents (TDS) were measured, and quantitative descriptive analysis (QDA) with 23 sensory attributes was performed for nine coffee samples. Hunter L values were significantly elevated with the degree of processing but reduced with roasting intensity. The pH values of the nine coffee samples were 5.6~6.2 and significantly increased with intensity of roasting. TDS decreased with an increase in processing and increased with roasting intensity. QDA results show that smoky aroma and nutty and chocolate flavor significantly increased while fruit and floral aroma decreased with intensity of processing. The attributes of brownness, oily surface, smoky aroma, bitter and burnt flavor, and greasy and heavy mouthfeel significantly increased while fruity and floral aroma, black tea, sour and umami flavor, pureness, and softness decreased as roasting intensity increased. Principle component analysis showed the overall significant relationships between 23 sensory attributes and nine coffee samples under different processing and roasting conditions.

• 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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.3
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• pp.341-348
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• 2014

We investigated the anti-obesity and anti-hyperlipidemic effects of extracts of two roasted coffee beans (Vietnam robusta and Ethiopia mocha sidamo G2) and fermented coffee beans with Monascus rubber mycelium (MR) by solid-state culture. C57B/L6 mice were divided into seven groups: normal diet (ND) group, high fat diet (HFD) group, and HFD groups with hot water extracts from Vietnam robusta coffee beans (HFD-VR), MR-fermented Vietnam robusta coffee beans (HFD-VR-MR), MR-fermented Vietnam robusta coffee beans with 10% brown rice (HFD-VR-MR-BR10), Ethiopia mocha sidamo G2 coffee beans (HFD-ES), and MR-fermented Ethiopia mocha sidamo G2 coffee beans (HFD-ES-MR). After 6 weeks, body weight gain and food efficiency ratio were higher in the HFD group, but significantly reduced in the coffee extracts-fed groups. The HFD-ES-MR group showed greater body weight reduction than the HFD-ES group. The serum triglyceride, total cholesterol, and LDL-cholesterol levels as well as the atherogenic index and cardiac risk factor all tended to decrease in groups fed Vietnam robusta coffee extracts compared to the HFD group. These results suggest that Vietnam robusta and Ethiopia mocha sidamo G2 may be used to make functional coffee beverages with anti-obesity and anti-hyperlipidemic activities.

• Food Science and Preservation
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• v.18 no.2
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• pp.178-183
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• 2011

The consumer awareness concerning coffee beverages has increased in Korea. The objective of this study was to optimize the roasting conditions of coffee bean for consumer's attribute. The optimal roasting conditions for Colombian coffee beans were analyzed by using a central composite design with a quadratic polynomial model by response surface methodology (RSM). The experimental conditions for coffee bean roasting were $194.82^{\circ}C{\sim}250.00^{\circ}C$ and 7.93~22.07 minutes. The responses of sensory attributes. physicochemical and physical properties were analyzed with RSM. The width. length and height of green beans increased when the beans were roasted. The higher degree of roasting gave the higher pH and solid contents but the lower total acidity and total phenolic compounds. In sensory tests, the roasting temperature and time had a significant effect on the flavor score. The optimum roasting condition of Colombian coffee bean predicted for maximizing the length, width, solid contents, total phenolic compounds and flavor score were 20 minutes at $225^{\circ}C$ by RSM.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.4
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• pp.579-585
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• 2015

The objective of this study was to investigate the quality characteristics of coffee soaked in Morus bombycis extract. Green coffee beans were soaked in M. bombycis extract for 2, 4, and 6 hours (sample codes: 2H, 4H, and 6H) at $4^{\circ}C$. Soaked green beans were dried and roasted for coffee extraction. Two controls, roasted with the same amount of heat (C1) and showed the same weight after roasting (C2), were used. Physicochemical characteristics (pH, total acidity, color, browning index, and total soluble solids), DPPH free radical scavenging activity (DPPH), ferric-reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), total polyphenol content (TPC), and total flavonoid content (TFC) were investigated. Lower pH and higher total acidity were observed in 2H, 4H, and 6H (P<0.05), supporting evidence of sour taste. There were significant differences in DPPH between the controls (45.51~47.02%) and samples (50.67~55.25%, P<0.05), although 2H and 6H did not show significantly higher DPPH than the controls. 2H, 4H, and 6H showed significantly higher FRAP values ($0.320{\sim}0.331\;FeSO_4{\cdot}7H_2O\;mM\;FeSO_4/g$) than controls ($0.265{\sim}0.271\;mM\;FeSO_4/g$). ORAC values of samples [1,062.86~1,153.68 mM trolox equivalent (TE)/g] were significantly higher than those of controls (689.40~942.12 mM TE/g). 2H, 4H, and 6H showed significantly higher TPC [24.27~26.07 mg gallic acid equivalent (GAE)/g] and TFC [3.75~4.28 mg quercetin equivalent (QE)/g] than controls (19.79~22.77 mg GAE/g and 1.07~1.95 mg QE/g, respectively) (P<0.05). M. bombycis extracts soaked into green coffee beans showed polyphenol compounds from green coffee beans. Consumer acceptance of 4H (5.12) was the highest, followed by C2 (4.92). C1 (4.14) showed the lowest consumer acceptance. Consumers were segmented into two groups, those who preferred M. bombycis extract-soaked coffee (approximately 61%) and controls (approximately 39%).

• Korean Journal of Food Science and Technology
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• v.52 no.3
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• pp.212-219
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• 2020

The physicochemical characterstics of El Salvadoran Coffea arabica cv. Bourbon coffee extracts under various roasting conditions were investigated. Green beans were roasted under four different conditions (Light-medium, Medium, Moderately dark, and Very dark). The coffee extracts were prepared by using the espresso or drip methods. As the roasting degree increased, the coffee bean moisture content decreased and the ash content increased. The lightness and yellowness of the beans and coffee extracts decreased along with the increasing roasting degree. In the drip coffee, the reducing sugar content decreased and the pH value increased along with the increasing roasting degree. Both in the espresso and drip coffee, total organic acid and chlorogenic acid contents decreased, while the caffeine content increased along with the increasing roasting degree. Therefore, it is suggested that the roasting degree affects the physicochemical characteristics of coffee extracts.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.153-158
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• 2006

Changes in contents of amino acids, caffeine, trigonelline, chlorogenic acid, and monosaccharides in green coffee beans during roasting were investigated. During roasting, amino acid contents of Arabica and Robusta coffees decreased by 30%, among which cysteine, serine, lysine, and arginine contents markedly decreased, whereas those of glutamic acid, glycine, alanine, valine, isoleucine, leucine, and phenylalanine slightly decreased or increased. Caffeine contents of Arabica and Robusta were 1 and 2%, respectively, and remained unchanged during roasting. Trigonellin content of Arabica (0.87%-0.90%) was slightly higher than that of Robusta (0.74%), and 50 to 65% trigonellin degraded when green beans were heavily roasted. Chlorogenic acid levels of Robusta and Arabica were 4.82, and 4.38-4.66%, respectively. About 90% chIorogenic acid degraded with heavy roating. Total monosaccharide contents of Arabica and Robusta were 38.1-38.7 and 37.7%, respectively, and gradually decreased with roasting.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.1
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• pp.134-138
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• 2013

Benzo[a]pyrene, a polycyclic aromatic hydrocarbon (PAH) whose metabolites are mutagenic and highly carcinogenic, is listed as a Group 1 carcinogen by the IARC. In this study, Arabica and Robusta green coffee beans were roasted under controlled conditions and the formation of benzo[a]pyrene during the roasting process was monitored. The concentration of benzo[a]pyrene in ground coffee and brewed coffee were determined by a HPLC-fluorescence detector. The limit of detection (LOD) and limit of quantitation (LOQ) of benzo(a)pyrene were 0.03 and $0.09{\mu}g/kg$, respectively. Benzo[a]pyrene was only detected in the dark roast of ground coffee, with a concentration ranging from $0.147{\sim}0.757{\mu}g/kg$. The content of benzo[a]pyrene in Ethiopia Mocha Harrar G4 is the highest ($0.757{\mu}g/kg$).

• Journal of the Korean Society of Food Culture
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• v.17 no.1
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• pp.78-89
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• 2002

Preferences of 814 elderly living in Incheon for dishes, food materials and cooking methods were investigated. The survey was conducted from Dec. 2000 to Jan. 2001 by questionnaires. Subjects preferred cooked rice with beans, kalkooksoo(hot noodle), gomtang(soup with beef), bibimbap(rice with assorted mixture) to other staple dishes. However, preference for hashed rice or curried rice was very low. More than 50% of the subjects liked soybean paste soup and stew, and the ratio of elderly who liked Chinese cabbage kimchi was 68.7%. There was no significant difference in preference for pan-fried foods according to food materials in them. Subjects liked injolmi(waxy rice cake), shikhye(fermented rice drink) and coffee the most. Most subjects preferred plant foods like vegetables, legumes and seaweeds to animal foods. Preference of elderly for milk and yoghurt was reatively high; however, that for ham, butter and cheese was low. Elderly in Incheon liked roasted beef, beef soup and roasted pork the most. Chicken was preferred when it was boiled in water with garlic, ginseng, and so on. Cooked and seasoned vegetables (Namul) were the most preferred type by elderly. Preferences for dishes and food materials were more affected by living places of the subjects than by sex, and the reverse was true in preference for cooking method of food materials.