• 한국조리학회지
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• 제24권1호
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• pp.140-150
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• 2018

In this study, effects of microground coffee on the quality characteristics and acceptability of instant coffee with probiotics were investigated. A central composite design with two factors (roasting degree and dose of microground coffee) was used and ranges of roasting degree and dose were 30~50 (L value) and 5~10% respectively. Aroma preference, sweetness intensity, bitterness intensity, acidity intensity, body intensity and overall acceptability were evaluated as sensory characteristics and quadratic regression models of all the properties were significant. Especially in aroma preference and overall acceptability, the higher roasting degree and dose of microground coffee, the more aroma preference and overall acceptability of the coffee increased. And this results accorded with the object of this study to increase aroma preference and overall acceptability by blending microground coffee with instant coffee. On the other hand, 129 of aroma compounds were detected in instant coffee with microground coffee but 2,5-dimethyl-pyrazine, ethyl-pyrazine and furfural were significant in quadratic regression models. The optimal conditions were predicted by response surface methodology and desirability function approach and the optimal conditions of roasting degree and dose of microground coffee were 30(L value), 8.4%(w/w) respectively to maximize 2 sensory characteristics (overall preference, aroma preference) and 3 aroma components (2,5-dimethyl-pyrazine, ethyl-pyrazine, furfural).

• 한국식품과학회지
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• 제52권3호
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• pp.212-219
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• 2020

본 연구는 로스팅 정도가 다른 엘살바도르산 Coffea arabica cv. Bourbon 커피의 이화학적 특성을 조사하기 위해 수행되었다. 로스팅 정도가 다른 원두의 일반성분, 중량 손실과 색도를 측정하였으며, 로스팅 정도가 다른 원두를 이용하여 추출한 에스프레소 커피와 드립 커피의 색도, 가용성 고형분, 환원당 함량, pH, 총 산도, 유기산, 카페인 및 클로로겐산 함량을 분석하였다. 로스팅이 강해짐에 따라 원두의 수분함량이 감소하고, 조회분이 증가하였으며, 명도와 황색도가 감소하였다. 에스프레소 커피와 드립 커피에서는 모두 로스팅 강도가 증가함에 따라 명도, 황색도, 갈색도가 감소하였다. 드립 커피에서는 로스팅 강도가 증가함에 따라 환원당 함량이 감소하였고, pH가 증가하였다. 에스프레소 커피와 드립 커피에서는 또한 로스팅이 강해짐에 따라 acetic acid, citric acid, L-malic acid와 oxalic acid를 포함하는 총 유기산과 클로로겐산의 함량이 감소하였으며, 카페인 함량이 증가하였다.

• 한국조리학회지
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• 제23권5호
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• pp.1-11
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• 2017

The objectives of this study were: 1) to examine the contents of chemical composition (chlorogenic acids, caffeine, free acids, and free sugars) and 2) to evaluate the sensory attributes (sourness, bitterness, and sweetness) of brewed coffee as affected by two roasting conditions such as varied in the roasting time with the same roasting temperature (RT) and with same color and yield (CY). Quantitative analysis of chemical components was performed using high-performance liquid chromatography (HPLC) system, and quantitative descriptive analysis (QDA) was conducted to analyze sensory attributes. Based on the results of chemical analysis, chlorogenic acids were significantly different (p<0.05) in the short term roasted samples (RT 240 and CY 240), but there was no significant difference in caffeine contents (p>0.05). Organic acid levels were different between RT and CY coffee samples. RT 240 coffee had the most level in organic acids and the longer the roasting time of coffee, the lesser the level of organic acids in coffee was found. However, there was no significant difference in CY coffee (p>0.05). The results of sensory evaluations show that the degree of roasting changed according to the roasting time despite of the roasting temperature. Long term (RT 80) coffee was relatively bitter while short term (RT 240) coffee was relatively sweeter. Also, there was no significant difference (p>0.05) in the sensory characteristics (bitterness and sweetness) of CY coffee although they were roasted at different temperatures. Therefore, the current study concluded that better understanding of proper roasting time and temperature improves the quality of brewed coffee.

• 동아시아식생활학회지
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• 제27권4호
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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.

• 한국식품영양학회지
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• 제26권1호
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• pp.51-59
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• 2013

This study aims to understand college students customer's preference and the difference of coffee grade by comparing the result of Q-grader, who was trained professionally and received certification for a sensory evaluation of coffee grade. The results of the chemical analysis of raw coffee and coffee berry show that those of specialty grade had slightly higher, but not significant, water content. Further, the pH of specialty grade coffee was high in coffee beans and after roasting, the commercial grade became high. There was no significant difference between the specialty degree and commercial degree in color before and after roasting. In this study, the panels for the sensory evaluation included 24 university students. The preference of evaluation items of sensory evaluation consist of aroma, acidity, bitterness, astringency, aftertaste, and overall satisfaction. Items for the strength evaluation consist of aroma, acidity and bitterness. The sensory evaluation was expressed by applying a 5 point Likert scale (1: extremely low~5: extremely high). In the sensory evaluation, it was evaluated that specialty grade coffee had strong acidity and commercial grade coffee was strongly bitter. The result of the sensory evaluation shows that female students are sensitive to coffee taste. In the analysis of frequent visit to coffee shop, the not-frequently-use-group rated that specialty grade coffee with higher overall satisfaction than commercial grade coffee in factors such as aroma and acidity. The group which did not prefer Americano coffee rated that specialty grade was higher than commercial grade in all factors except aroma, of which the result is similar to the cupping test.

• 한국식품저장유통학회지
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• 제18권2호
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• pp.178-183
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• 2011

반응표면분석법에 의해 생두를 실험 조건인 $194.82^{\circ}C{\sim}250.00^{\circ}C$의 온도 범위에서 7.93~22.07분의 조건으로 커피원두를 배전하여 이화학적 분석, 물리적 특성, 관능검사 등을 실시하여 최적 조건을 설정하였다. 배전 정도가 커짐에 따라 직경, 길이, 두께 모두가 증가하여 전체적인 팽창률은 증가했지만, 겉보기 밀도의 변화는 그 차이가 적은 것으로 나타났다. pH는 증가하는 반면 총산도와 총페놀함량은 감소하는 경향을 나타내었으며, 고형분함량은 증가하는 유의성을 가지고 있는 것으로 나타났다. 색도는 전체적으로 배전에 의해 갈색에서 검은색으로 변화하며 색도값이 감소하는 형태로 나타났다. 관능검사에 의해서는 전체적인 향과 맛에 따라 큰 차이를 보였으며 향이 배전 조건과 연관성이 높은 것으로 나타났다. 유의성을 나타낸 길이, 폭, 향, 고형분 함량과 총페놀함량으로 배전 조건을 설정한 결과, $225^{\circ}C$에서 20분간 배전하는 것이 본 연구 조건에서는 최적의 배전 조건으로 결정되었다.

• 한국식품영양학회지
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• 제32권4호
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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.

• 한국식품저장유통학회지
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• 제22권5호
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• pp.690-698
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• 2015

아라비카 커피 생두 3종(브라질 버번, 인도네시아 만델링, 케냐 타투)을 배전 온도 $181{\sim}215^{\circ}C$의 범위에서 8.15~11.83분의 조건에서 약배전, 중배전, 강배전으로 배전하여 물리적 특성, 이화학적 성질, 항산화력 등을 조사하였다. 배전 온도가 증가함에 따라 무게와 밀도가 감소하였고, $L^*$, $a^*$, $b^*$값이 감소하였다. 총 페놀함량은 생두보다는 배전후의 원두에서 더 높았으며, 약배전과 중배전에서 가장 높았다. 카페인 함량은 강배전한 시료에서 가장 높았다. 클로로겐산은 생두에서 가장 높았으며, 배전의 강도가 강해짐에 따라 감소하였다. ABTS와 DPPH 라디칼 소거능은 생두보다는 배전 후의 원두에서 더 높았으며, 배전의 강도가 강해짐에 따라 감소하였다. 따라서 항산화력을 유지하기 위해서는 지나치게 높은 온도에서 배전하는 것보다는 낮은 온도에서 약배전하는 것이 바람직한 것으로 사료된다. GC를 기초로 한 전자코를 활용하여 커피의 향기패턴을 분석한 결과 품종과 배전정도에 따른 향기패턴의 차이를 잘 구분할 수 있었다.

• Journal of Applied Biological Chemistry
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• 제60권4호
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• pp.383-390
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• 2017

쉽게 산화되는 지방이 커피의 풍미에 중요한 영향을 미치는 주요 요소 중 하나라는 것과 chlorogenic acid (CGA)가 커피의 주요 항산화 물질이라는 점을 고려하여 본 연구에서는 커피생두의 열처리 가공 정도와 단기저장 기간에 따라 변화하는 지방의 산화와 CGA의 농도변화와 동시에 항산화활성을 분석하였다. 커피 원두를 얻기 위한 열처리 가공 시간이 길수록 diethyl ether로 추출되는 지방의 양이 증가하였으며 지방의 산가는 분쇄된 medium과 dark 커피에서 가공 첫날 $8.91{\pm}0.16$과 $10.37{\pm}0.27$를 각각 보이다가 60일 간의 저장기간 후에는 $17.81{\pm}0.11$과 $17.93{\pm}0.09$로 증가하였으나 분쇄 생두에서는 $4.47{\pm}0.11$로부터 $11.89{\pm}0.18$로 증가함을 보였다. CGA 함량은 10 g 커피를 이용하여 커피를 제조할 경우 생두, medium, dark 커피의 경우 각각 $310{\pm}8.2$, $282{\pm}11.2$, $5.9{\pm}0.23mg$을 나타내었으며 이들 농도는 60일간의 저장 기간 동안 변화되지 않고 유지되었을 뿐 아니라 CGA를 분리하는 액체 크로마토그래피 조건에서 얻어지는 용리 크로마토그램도 저장기간 동안 변화되지 않고 유지되어 CGA가 저장기간 동안 다른 물질로 변화되지 않음을 보였다. 2,2-diphenyl-1-picrylhydrazyl와 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid radical 소거능 분석에서 원두 간 그리고 저장기간에 따른 특이적인 변화를 보이지 않았으며 ARE-luciferase 활성 분석에서는 오히려 roasting이 진행될수록 저장기간이 오랠수록 항산화활성이 증가함을 보였고 총 polyphenol의 함량은 roasting가공이 진행됨에 따라 감소함을 보였기 때문에 커피의 항산화활성은 polyphenol 외에 다른 물질, 즉, melanoidin과 같은 물질이 생성되어 항산화활성을 높이고 커피 풍미에도 영향을 미칠 가능성을 보였다.