• Korean journal of food and cookery science
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• v.25 no.6
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• pp.703-711
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• 2009

Arabica coffee is classified for trading according to the New York Board of Trade(NYBOT) green coffee classification. NYBOT's grading system is based on classification derived from a defect count on a 300 g sample. In the present study, green and roasted coffees were investigated for possible correlations between the content of defective beans and sensory characteristics. Sensory evaluation was performed by expert tasters used by the Specialty Coffee Association of America(SCAA) cupping method. For green coffee, the percentage of defective beans increased. as the coffee grade decreased. Black and sour beans were not found in the NY2 grade coffee out of all natural, pulped natural, and washed coffee samples. Sour and insect damage were found in more natural coffee samples as the green coffee grade decreased. Green and broken beans were found in more washed coffee samples as the green coffee grade decreased. Flavor, clean, uniformity, aftertaste, and overall sensory characteristics were significantly different among the NY2, NY3/4 and NY4/5 grade coffee in all natural, pulped natural and washed coffee samples. The natural coffee in the NY2 sample presented the highest body characteristic. The pulped natural coffee in the NY2 sample presented the highest sweetness and balance characteristics. The washed coffee in the NY2 sample presented the highest acidity and flavor characteristics. In conclusion, the percentage of defective beans increased as sensory characteristics decreased.

• Journal of the Korean Home Economics Association
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• v.24 no.3
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• pp.119-127
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• 1986

To investigate differences in fatty acid composition in green coffee beans and roasted coffee beans, the extracts of two beans were subjected to analysis of fatty acid composition by GC and HPLC. The results showed that palmitic and liolneic acid were the main fatty acids of coffee oil and their contents were about 40%. Minor components, such as capric acid, lauric acid and myristic acid were detected in both samples by GC, but nut HPLC.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.30 no.2
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• pp.236-248
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• 2020

Objectives: The purpose of this study was to evaluate the concentrations of particulate matter generated during coffee roasting and to study various factors affecting the concentrations. Methods: Differences in concentration levels were investigated based on various factors to understand the emission rates of particulate matter over time and to compare the mass and number concentrations according to their size. Sampling was performed in closed laboratories without the operation of air conditioning or ventilation. Optical Particle Sizer(OPS) was used as a measuring device. An OPS measures using a light-scattering method. Sampling was performed for sixty minutes at one-minute intervals. The background concentration was measured for about 30 minutes before starting of coffee roasting. The concentrations of particulate matter generated during coffee roasting were monitored until roasted coffee beans were removed from the roaster and cooled down. Several factors affecting the concentrations of particulate matter were investigated, which includes the origins of green beans, the roasting level, and the input amount of green beans. Results: The results of this study may be summarized as follows: 1) There was no difference in particulate matter concentration levels by the origin of the green beans, but a statistically significant difference in concentration levels by roasting level and the input amount of green beans; The higher the roasting level, the higher was the particulate matter concentration. The more green beans we put in the roaster, the higher were the concentrations; 2) The PM10 mass concentrations increased over time. The average concentration after roasting was higher than the average concentration during roasting; 3) In the distribution of mass and number concentration by particle diameter, the majority of particles was below 2.5 ㎛. Conclusions: Persons who work in roastery cafes can be exposed to high concentrations of particulate matter. Therefore, personal exposure and risk assessment should be conducted for roastery cafe workers.

• Preventive Nutrition and Food Science
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• v.18 no.1
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• pp.30-37
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• 2013

In vitro antioxidant activities and neuronal cell protective effects of ethanol extract from roasted coffee beans were investigated. Colombia arabica coffee (Coffea arabica) green beans were roasted to give medium ($230^{\circ}C$, 10 min), city ($230^{\circ}C$, 12 min) and french ($230^{\circ}C$, 15 min) coffee beans. Total phenolics in raw green beans, medium, city and french-roasted beans were $8.81{\pm}0.05$, $9.77{\pm}0.03$, $9.92{\pm}0.04$ and $7.76{\pm}0.01$ mg of GAE/g, respectively. The content of 5-O-caffeoylquinic acid, the predominant phenolic, was detected higher in medium-roasted beans than others. In addition, we found that extracts from medium-roasted beans particularly showed the highest in vitro antioxidant activity on ABTS radical scavenging activity and FRAP assays. To determine cell viability using the MTT assay, extracts from medium- roasted beans showed higher protection against $H_2O_2$-induced neurotoxicity than others. Lactate dehydrogenase (LDH) leakage was also inhibited by the extracts due to prevention of lipid peroxidation using the malondialdehyde (MDA) assay from mouse whole brain homogenates. These data suggest that the medium-roasting condition to making tasty coffee from Columbia arabica green beans may be more helpful to human health by providing the most physiological phenolics, including 5-O-caffeoylquinic acids.

• Culinary science and hospitality research
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• v.22 no.6
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• pp.114-119
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• 2016

This study aimed to investigate changes in the diverse compound in coffee beans under different roasting conditions. Four different kinds of chemical characteristics (phenolic contents, flavonoid contents, chlorogenic acid, and caffeine) were analyzed. According to the temperature of coffee roasting, this study categorized green bean, extract A ($191^{\circ}C$), B ($202^{\circ}C$), C ($220^{\circ}C$), and D ($233^{\circ}C$). As a result, total phenol compound showed low level of total phenol compound at lower temperatures. Extract A showed significantly higher level of total flavonoid ($111.33{\pm}10.14$), green bean showed $83.67{\pm}2.43$, Extract B $46.11{\pm}2.38$, C and D showed $31.44{\pm}0.12$, $19.22{\pm}0.46$ respectively. Green bean showed higher level of chlorogenic acid ($64.47{\pm}0.51$), Extract A ($39.66{\pm}0.47$), extract B ($12.45{\pm}0.99$), C, D ($3.59{\pm}0.31$, $0.63{\pm}0.12$) respectively. This study also noted that there are significant different in terms of caffeine content. Extract A has higher level of caffeine content ($38.45{\pm}1.70$) significantly, green bean ($27.14{\pm}2.27$), extract B ($18.95{\pm}0.64$), extract C ($17.89{\pm}0.96$). As a conclusion, we revealed that roasting conditions play an important role in the composition of coffee compounds.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.198-202
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• 2018

The present study aimed to investigate the effect of germination and temperature on the antioxidant activity of coffee. Green beans were germinated at 20 and $40^{\circ}C$. Germinated green beans were dried and roasted. Ground coffee was brewed at $90^{\circ}C$ for 5 min. Coffee samples were analyzed for antioxidant compounds and for its antioxidant activity. The total polyphenol content (TPC) and total flavonoid content (TFC) in coffee brewed with coffee beans germinated at $20^{\circ}C$ (CG20) were significantly higher than those in coffee brewed with non-germinated coffee beans (CNG). The same tendency was observed on 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging assays. TPC and TFC of coffee brewed with germinated coffee beans decreased with an increase in germination temperature from 20 to $40^{\circ}C$. In conclusion, germination of coffee beans contributes to an increase in its antioxidant activity. However, setting the appropriate temperature for germination is an important factor in determining the antioxidant activity of coffee.

• 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.

• The Korean Journal of Food And Nutrition
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• v.32 no.4
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• pp.312-320
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• 2019

This study examines the changes in chlorogenic acid (CGA), an antioxidant, and one of its decomposition substances, caffeic acid, at various roasting stages and extraction conditions. Based on the CGA content for each roasting stage, at $3^{\circ}C$ after the beginning of the $1^{st}$ crack, the CGA decreased for washed beans and natural beans by more than 50% compared to that of green coffees. The CGA continued to decrease sharply by more than 75% at the end of the $1^{st}$ crack for washed beans and at $5^{\circ}C$ after the end of the $1^{st}$ crack for natural beans. At the peak of the $2^{nd}$ crack, it had decreased by more than 90% for both beans. The Caffeic acid content gradually increased for both washed and natural beans, then rapidly increased from the beginning of the $2^{nd}$ crack to the peak of the $2^{nd}$ crack. However, its contents were very small in quantity. Additionally, the content of CGAs for differing extraction conditions were in the order of 3-CGA, Crypto-CGA, and Neo-CGA. Crypto-CGA content was about half that of 3-CGA and Neo-CGA content was approximately 100 ppm less than that of Crypto-CGA. This study was conducted in order to help make coffee that has the most antioxidant effect.

• 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.

• Culinary science and hospitality research
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• v.10 no.3
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• pp.65-82
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• 2004

This research is to make an attempt the analysis award consumption state, import and export in the world coffee market. This research results were as follows. First, The result of the analysis of Korea coffee market, imports of green bean were 1,316,000 bags from export countries in 2000. Re-exports of processed coffee were 71,000 bags in 2000. Main suppliers were Brazil, Viet Nam, Honduras, Colombia, Indonesia. Second, The result of the analysis of United State coffee market, imports of all forms of coffee were 19.29 million bags. Main suppliers were Brazil(15%), Viet Nam(15%), Colombia(17%) etc. Third, The result of the analysis of Japan market, imports of green beans were 6.37million bags in 2001. Re-exports of processed coffee were 166.000million bags. Consumption per head in 2001 was about 3.5 kg and Japanese coffee consumer now drink on average 11.0 cups per week.