JP2004305167A - Method for producing roasted coffee bean - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing roasted coffee beans by which taste of coffee can be positively regulated without depending on origin of raw coffee beans. <P>SOLUTION: The method for producing roasted coffee beans comprises a process of hot-air roasting of raw coffee beans. In the method, roasting time is varied by regulating the time when the temperature of the roasted beans reaches to a prescribed one selected from 200-230°C so as to enrich the taste of roasted coffee beans. By this method, a short-time roast results in making the coffee taste highly acidulated, and a long-time roast results in making the coffee taste much more bitter and richer in flavor and providing such roasted beans as to produce extract with slight cloudiness. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

（２）抽出液の液性
前記（１）で焙煎したコーヒー豆をそれぞれ粉砕し、抽出器（ＢＯＮＭＡＣ ＮＣ１１０５）に入れ、粉砕コーヒー豆の１８倍の加水比でドリップ抽出し、コーヒー抽出液を得た。抽出液のｐＨと吸光度を測定し、その結果を表２に示す。
【００４９】
【表２】

表２より、コーヒーの焙煎時間が長くなるほど、抽出液のｐＨは高くなり、濁り（吸光度７２０ｎｍ）が少なくなることがわかった。
【００５０】
（３）抽出液のガスクロマトグラフィーによる分析結果
ガスクロマトグラフィーによるピークの総面積を算出し比較した。また、各ピークを分析時のカラムの温度を基に３つのエリアに分類し、各エリア別のピーク面積を算出した。またそれぞれの各成分の構成を調べた。
【００５１】
【表３】

【表４】

表３より、コーヒーの焙煎時間が長くなると、抽出液中には沸点の高い成分が増加する。表４より、焙煎時間が長いほど、刺激性の有る成分は少なくなり、後味に切れが有る風味となることが成分的にも示されている。苦味に関係する成分ピリジンは、焙煎時間が短いほど少なく、逆に長いほど多くなる。また、２−メチルフランも焙煎時間とともに増加している。焙煎時間の長いコーヒー豆の抽出液には、苦味の強い深炒の豆に多いとされるピリジンや２−メチルフランが多くなっていることが分かる。これにより焙煎時間が短いほど、苦味は少なくなり、長いほど苦くなることがわかる。
【００５２】
（４）官能評価結果
抽出液を専門パネラー６名により評価した結果を表５に示す。焙煎時間１０．０分を基準（±）として評価した。
【００５３】
【表５】

表５より、官能的にも焙煎時間が短いほど、コーヒー抽出液の酸味は強くなり、長くなるほど弱くなる。苦味と濃厚感は１０分以内では官能的な差は殆ど感じられないが、１７分以上になると強くなる傾向が有る。
【００５４】
実施例２
コロンビアの焙煎時間を変化させた場合の味覚および成分の変化
コーヒー生豆オリジンとしてコロンビアＥＸを選択した。コロンビアＥＸをＰｒｏｂａｔ社製小型サンプルロースター（形式：Ｂｒ３Ｐ１００）に投入し、焙煎機内の炒豆表面温度が２０８℃±５℃に到達する時間（焙煎時間）を変えて焙煎し、同じ焙煎色（Ｌ２２．５前後）になるようにした。焙煎前のコーヒー豆の表面温度は、２１℃であった。
【００５５】
焙煎機、抽出条件およびガスクロマトグラフィーの測定条件は、実施例１と同様である。
【００５６】
（１）焙煎時間と焙煎色
【表６】

（２）抽出液の液性
【表７】

表７より、焙煎時間が長くなるほど、コーヒー抽出液のｐＨは高くなり、濁り（吸光度７２０ｎｍ）は少なくなる。コロンビアは、サントスＮｏ４に比べてｐＨの変化は小さいことがわかる。
【００５７】
（３）抽出液のガスクロマトグラフィーによる分析結果
【表８】

【表９】

表８より、実施例１のサントスＮｏ４と比べて、焙煎時間が長くなっても沸点別構成比の変化は殆どないことがわかる。表９より、実施例１と同様に、焙煎時間が長いほど、刺激性の有る成分は少なくなり、後味に切れが有る風味となることが成分的にも示されている。苦味に関係するピリジンもサントスＮｏ４と同様に焙煎時間が短いほど少なく、長いほど多くなる。これより焙煎時間が短いほど、苦味は少なくなり、長いほど苦くなることがわかる。
【００５８】
（４）官能評価結果
抽出液を専門パネラー６名により評価した結果を表１０に示す。焙煎時間１０．０分を基準（±）として評価した。
【００５９】
【表１０】

表１０より、官能的にも焙煎時間が短いほど、酸味は強くなり、長くなるほど弱くなる。苦味と濃厚感はサントスＮｏ４の場合と異なり、官能的な差は小さく感じられない。ガスクロマトグラフィーのピリジンは増加するが、変化が小さいので官能的な差を感じ難い。
【００６０】
実施例３
インドネシアＡＰ−１の焙煎時間を変化させた場合の味覚および成分の変化
コーヒー生豆オリジンとしてロブスタ種インドネシアＡＰ−１を選択した。インドネシアＡＰ−１をＰｒｏｂａｔ社製小型サンプルロースター（形式：Ｂｒ３Ｐ１００）に投入し、焙煎機内の炒豆表面温度が２２５℃±５℃に到達する時間（焙煎時間）を変えて焙煎し、同じ焙煎色（Ｌ２１．５前後）になるようにした。焙煎前のコーヒー豆の表面温度は、２３℃であった。
【００６１】
焙煎機、抽出条件およびガスクロマトグラフィーの測定条件は、実施例１と同様である。
【００６２】
（１）焙煎時間と焙煎色
【表１１】

（２）抽出液の液性
【表１２】

表１２より、焙煎時間が長くなるほど、コーヒー抽出液のｐＨは高くなり、濁り（吸光度７２０ｎｍ）は少なくなる。インドネシアＡＰ−１は、サントスＮｏ４に比べてｐＨの変化は小さいことがわかる。
【００６３】
（３）抽出液のガスクロマトグラフィーによる分析結果
【表１３】

【表１４】

表１３より、インドネシアＡＰ−１は、サントスＮｏ４と比べて、焙煎時間が長くなっても沸点別構成比の変化はほとんどない。表１４より、実施例１および２と同様に、焙煎時間が長いほど刺激性の有る成分は少なくなり、後味に切れが有る風味となることが成分的にも示されている。ピリジンや２−メチルフランもサントスＮｏ４と同様に焙煎時間が短いほど少なく、長いほど多くなる。これにより焙煎時間が短いほど、苦味が少なくなり、長いほど苦味が増すことがわかる。
【００６４】
（４）官能評価結果
抽出液を専門パネラー６名により評価した結果を表１５に示す。焙煎時間９．３分を基準（±）として評価した。
【００６５】
【表１５】

表１５より、官能的にも焙煎時間が短いほど酸味は強くなり、長くなるほど弱くなる。苦味と濃厚感は、官能的な差は小さいが、焙煎時間が長いほど強くなる。ガスクロマトグラフィーでのピリジン含有量は増加したが、サントスＮｏ４の場合と異なり変化が小さいので官能的な差も小さい。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a technique belonging to the field of roasting coffee, and more particularly, to a method for creating a taste of coffee by controlling a roasting time.
[0002]
[Prior art]
Originally, nutrients, palatability, economy, safety, etc. are said to be basic elements required for food, but in coffee, palatability with a focus on taste and aroma is the most important. Food. By applying a heat treatment called roasting, coffee produces a unique color, aroma and taste. This is due to the fact that various components of green beans cause a continuous and complicated chemical reaction by heat, and through roasting, the taste and aroma components unique to coffee are also formed. For roasting these coffees, a batch drum roaster represented by Probat of Germany, a continuous roaster of Burns of the United States of America, a fluidized bed roaster of NEOTECH, a rotary ball type of Probat (radial turbo) (Formula) Various roasting machines such as roasting machines are used in coffee makers around the world (see Non-Patent Document 1).
[0003]
What is important here is what each manufacturer using the roaster does to achieve the desired taste. It is a combination of the degree of roasting and the origin of green beans, and the taste is realized by blending them. This is because the flavor of coffee originally differs depending on the raw bean origin of the coffee beans, and the strength of acidity and bitterness changes depending on the degree of roasting.
[0004]
As a taste characteristic of general raw bean origin, the pH (20 ° C.) of coffee liquid of Arabica is 4.9 to 5.3, and the pH (20 ° C.) of coffee liquid of Robusta is 5.1 to 5. The acidity tends to be higher than that of the lowland, and the acidity is higher in the highlands than in the lowlands. Further, in roasting degree, lightly roasted coffee tends to have a strong acidity and low bitterness, but deeply roasted coffee tends to have a low acidity and a strong bitterness. Therefore, each maker produces a coffee taste by blending beans with different roasting degrees and beans with different origins.
[0005]
There are many prior art methods of changing the flavor of coffee. For example, there is a technique for weakening unpleasant aroma and flavor of Robusta seeds by roasting raw beans that have been steamed and moistened with Robusta seeds before roasting (see Patent Document 1). Although this method is an effective method for improving the flavor of Robusta species, the richness of Robusta species tends to be weak. Furthermore, this method cannot be used for Arabica species with high quality origin properties. This is because it reduces the good flavor characteristics inherently retained by the Arabica species.
[0006]
Similarly, as a method of using steam, there is a method of roasting by applying steam having a pressure of 5 bar or more (see Patent Document 2). This method is one of the roasting methods using steam and is an effective method for roasting, but requires a special roasting machine capable of roasting with steam.
[0007]
As a method for improving the taste as a coffee beverage, there is a method of obtaining good taste characteristics by extracting the coffee under the optimum extraction conditions for each roasting degree and origin in the step of extracting coffee (see Patent Document 3). This method is a technique for optimizing extraction conditions, and is not a technique for changing the original taste of roasted coffee beans.
[0008]
As a technique for pre-treating green beans, there is a method of pre-treating green coffee beans to reduce the roasted beans moisture content after roasting to 5% (see Patent Document 4). In this method, it takes time to use protein-containing soft water, irradiate with low far-infrared rays, immersion treatment and drying.
[0009]
[Non-patent document 1]
Clark (RJ), Coffee (COFFEE), Volume 2, "TECHNOLOGY," ELSEVIER APPLIED SCIENCE 1987, Chapter 4 [Patent Document 1]
JP-A-6-303905 [Patent Document 2]
Japanese Patent Publication No. Hei 9-502099 [Patent Document 3]
JP 2000-175623 A [Patent Document 4]
Japanese Patent Application Laid-Open No. 2002-17261
[Problems to be solved by the invention]
As described above, in the case of realizing the taste only by the combination of the degree of roasting and the raw bean origin, each manufacturer always bears the following risks, which is considered to be a problem from the viewpoint of securing stable profits.
(1) Because coffee beans are agricultural products, it is difficult to reproduce a stable taste every year.
(2) Shortage of single-origin beans due to changes in agricultural policies in producing countries, as well as climatic problems and diseases.
(3) Significant fluctuations in the procurement price of raw coffee beans due to exchange rate fluctuations. It is a social responsibility for manufacturers to overcome these risks and provide consumers with a stable taste at an appropriate price. Therefore, an object of the present invention is to provide a method for positively controlling the taste of coffee without depending on the raw bean origin.
[0011]
[Means for Solving the Problems]
The present inventor has conducted intensive studies on a method of changing the taste by devising roasting conditions even for the same green bean origin in order to achieve the above object, and by changing the roasting time of green coffee beans, Paying attention to changes in liquid properties and constituent components, they found that the changes corresponded to sensory taste changes, and completed the present invention.
That is, in the method for producing roasted coffee beans of the present invention, in the method for producing roasted coffee beans including the step of roasting green coffee beans with hot air, the time required for the temperature of roasted beans to reach a temperature selected from 200 to 235 ° C. By changing the roasting time, the taste of the roasted beans is enhanced.
[0012]
Preferably, the green coffee beans are Robusta seeds, and the roasting time is less than 6 minutes to enhance the acidity of Robusta roasted beans.
[0013]
Preferably, the green coffee beans are Arabica seeds, and the roasting time is set to 17 minutes or more to enhance the bitterness of the Arabica seed roasted beans.
[0014]
The roasted color of the roasted coffee beans is preferably medium roast with an L value of 20 to 26.
[0015]
It is preferable that the roasting time is 17 minutes or more, whereby the roasted beans supplying the less turbid extract are produced.
[0016]
[Effects]
According to the method for producing roasted coffee beans of the present invention, it is possible to control the taste of coffee by actively controlling the roasting time without relying on the raw bean origin and the degree of roasting. By this method, it is possible to enhance the bitterness by suppressing the acidity of the washed Arabica species from Latin America, which is generally considered to have a strong acidity, or to enhance the acidity of the robusta species, which is considered to have a weak acidity. Become. Further, according to the method for producing roasted coffee of the present invention, as a cappuccino, latte, and espresso coffee beans that are often drunk in recent years, the desired bitterness and richness have been enhanced without depending on the characteristics of the raw bean origin. It is also possible to provide coffee beans. Further, by setting the roasting time to a long time of 17 minutes or more, it is possible to provide a roasted coffee that can supply a coffee extract with less turbidity in addition to enhancing bitterness.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
The method for producing roasted coffee beans of the present invention includes a step of roasting green coffee beans with hot air, and controlling roasting time by controlling the temperature of roasted beans to reach a temperature selected from 200 to 235 ° C. It changes the flavor and enhances the taste of roasted beans.
[0018]
The roasting machine used in the method of the present invention is not particularly limited, but RJ Clarke, COFFEE Volume 2, "TECHNOLOGY" ELSEVIER APPLIED SCIENCE 1987, Known hot air roasters, such as batch drum roasters, continuous roasters, fluidized bed roasters, and rotating ball roasters, as described in Chapter 4, may be mentioned.
[0019]
The green coffee beans to be roasted are not particularly limited, but green coffee origins consumed worldwide can be used without limitation. Typical raw bean origins include Santos (Brazil), Colombia (Colombia), Indonesian lob (Indonesia), and mocha (Ethiopia), which is highly recognized by consumers. The difference in the selection method in the raw bean producing country, for example, the selection method using a washing method or a non-washing method, is not particularly limited.
[0020]
The green beans are put into the roasting machine and hot air roasting is performed.
[0021]
First, the temperature reached in the roasting machine is set in relation to the roasting degree of the finished coffee roasted beans. Usually, the attained temperature is 200 to 235 ° C, preferably 205 to 230 ° C, more preferably 208 to 225 ° C. When the attained temperature is within the above range, the roasting degree of the coffee is medium roasting in which the effects of the present invention are easily exerted, and the attained time, that is, the heat control of the roasting machine is in a range where the roasting machine can be controlled. Here, the attained temperature refers to the surface temperature of the coffee beans in the roasting machine. The surface temperature of the coffee beans is a value measured using a non-contact infrared radiation thermometer (manufactured by Keyence Corporation, type IT-2-80). At the time of roasting, in order to achieve a desired degree of roasting, the actual temperature may be about ± 5 ° C. of the set temperature.
[0022]
Next, the time to reach the set temperature is determined, and the heat supplied to the inside of the roaster is controlled so as to reach the temperature at that time.
[0023]
The arrival time can be appropriately set depending on the type of raw beans and the taste of the roasted beans to be strengthened. In the present invention, the arrival time is the roasting time.
[0024]
What is said to be important in the taste of coffee is sourness and bitterness, which most contribute to consumer preference decisions. Another important taste element is richness. This is also a factor in determining the overall impression of the consumer when drinking. The term "enhancing the taste of roasted beans" in the present invention means to enhance such tastes as acidity, bitterness, and richness, but is not limited to these tastes.
[0025]
Changes in roasting time and taste when the roasting degree is kept constant will be described. Even if the roasting degree is the same for the same raw bean origin, if the roasting time reaches a predetermined roasting degree in a shorter time, the acidity can be increased and the bitterness can be reduced. On the other hand, if the roasting time reaches a predetermined degree of roasting for a longer time, the acidity can be reduced and the bitterness can be increased.
[0026]
Describing the change in the liquid properties of the coffee extract when the roasting degree is constant, the pH of the extract tends to increase as the roasting time increases. As a general flavor, it goes without saying that the lower the pH, the stronger the sourness. Conversely, the shorter the roasting time is, the lower the pH tends to be, and the sourness also increases. In addition, the turbidity of the extract tends to decrease as the roasting time increases.
[0027]
Describing the change in components of the coffee extract when the roasting degree is constant, the longer the roasting time, the more organoleptically irritating components, acetaldehyde, 2-methylbutanal, isovaleraldehyde, Acetic acid and furfural are reduced. This sensuously means a mild, mild flavor. Deep roasted coffee beans, such as those used for iced coffee, are very bitter sensually, and have a characteristic that they contain a lot of 2-methylfuran and pyridine. 2-Methylfuran and pyridine increase. This means that the bitterness becomes stronger organoleptically.
[0028]
In addition, the roasted soybean extract has a relatively high boiling point compared to lightly roasted, but the roasting time is longer at the same roasting degree. It shows a similar tendency.
[0029]
These tendencies are the same even when the raw bean origin is different. The only difference is the degree of sensory change, because the original sensory characteristics differ depending on the origin.
[0030]
Therefore, it is possible to change the taste of coffee by changing the roasting time even at the same roasting degree.
[0031]
In the process of roasting green coffee beans, various chemical reactions occur at the green bean origin in each locality, and it goes without saying that the taste and aroma of coffee are also generated by the chemical reaction due to roasting. Even with the same roasting degree,
1. In the case of Santos (Brazilian non-washed Arabica), shortening the roasting time can increase the acidity and reduce the bitterness. Conversely, by increasing the roasting time, acidity can be reduced and bitterness can be increased.
2. In the case of Colombia (Columbian water-washed Arabica), the acidity can be reduced by increasing the roasting time.
3. In the case of Indonesia (Indonesia non-washed Robusta), shortening the roasting time can increase the acidity. Conversely, by increasing the roasting time, acidity can be reduced and bitterness can be increased.
[0032]
Each of these raw bean origins has a different effect on taste because each origin originally has a different characteristic flavor. In other words, Santos is characterized by a neutral (not particularly sour or bitter) taste, Colombia is characterized by an irritating strong acidity, Indonesia is weakly acidic, and has a strong bitterness and richness. And so on.
[0033]
In the present invention, when the green coffee beans are robusta, it is preferable to enhance the acidity of the roasted roasted beans by setting the roasting time to less than 6 minutes. The roasting time is more preferably 3 to 6 minutes.
[0034]
In the present invention, when the green coffee beans are Arabica, the roasting time is preferably set to 17 minutes or more to enhance the bitterness of the Arabica seed roasted beans. The roasting time is more preferably 17 to 20 minutes.
[0035]
The roasted color of roasted coffee beans after roasting can be appropriately set in relation to the taste, but is preferably medium roasted with an L value of 20 to 26. When the L value is within the above range, the effects of the present invention can be sufficiently exhibited.
[0036]
In the present invention, when the roasting time is set to 17 minutes or more, it is possible to produce a roasted bean that enhances bitterness and supplies a less turbid extract. To reduce turbidity, the roasting time is more preferably 17 to 20 minutes.
[0037]
Turbidity of the coffee extract can be confirmed visually or by measuring absorbance with a spectrophotometer.
[0038]
【Example】
Hereinafter, examples and the like specifically illustrating the configuration and effects of the present invention will be described, but the present invention is not limited to these examples and the like. The measuring method common to the following examples and the like is as follows.
[0039]
[Measurement of temperature]
The temperature of the roasted coffee beans was determined by measuring the surface temperature of the coffee using a non-contact infrared radiation thermometer (type IT-2-80, manufactured by Keyence Corporation).
[0040]
[Measurement of L value]
The L value of the roasted coffee beans was measured with an L value measuring device (Type ZE-2000, manufactured by Nippon Denshoku Industries Co., Ltd.).
[0041]
[Measurement of pH]
The pH of the coffee liquid was measured at 20 ° C. with a pH meter (manufactured by TOA, HM-30G).
[0042]
[Measurement of turbidity]
The turbidity of the coffee liquid was examined by measuring the absorbance at 720 nm with a spectrophotometer (U-1500, manufactured by Hitachi, Ltd.).
[0043]
[Measurement of odor components by gas chromatography]
The amount of aroma components contained in the coffee liquid was analyzed by gas chromatography under the following conditions. The obtained chromatogram was input to a computer, and the total intensity area of each peak was calculated and compared. Further, each peak was classified into the following three areas based on the column temperature at the time of analysis, and the peak area for each area was calculated. The composition of each component was examined.
High boiling point area: Column temperature 101-200 ° C
Medium boiling point area: Column temperature 41-100 ° C
Low boiling point area: column temperature 40 ° C.
[0044]
(A) Preparation of Measurement Sample 10 g of each coffee liquid was collected in a 22 ml vial and sealed. The sealed vial was heated at 80 ° C. for 20 minutes with an autosampler for gas chromatography manufactured by Tekmar, and the gas phase was introduced into the gas chromatography for analysis.
[0045]
(B) Measuring conditions Measuring device: Hitachi Gas Chromatography G-3000
Column: TC-WAX 0.53 mm x 30 m, manufactured by GL Sciences Corporation
Carrier gas: helium carrier gas flow rate: 1 ml / min Column temperature 40 ° C for 5 minutes → 220 ° C (temperature rises at 5 ° C / min)
Detector: FID (detector temperature 230 ° C.).
[0046]
[sensory evaluation]
The sensory evaluation of the coffee liquid was performed at 65 ° C. The evaluation method was performed by six expert panelists, and the total evaluation of aroma and flavor was ++: very strong, +: strong, ±: normal,-: weak,-: extremely weak, and represented by the highest evaluation .
[0047]
Example 1
Changes in taste and components when the roasting time of Santos was changed Santos No. 4 was selected as a representative raw bean origin. Santos No. 4 is put into a Probat small sample roaster (model: Br3P100), and roasting is performed by changing the time until the surface temperature of the roasted beans in the roasting machine reaches 215 ° C. ± 5 ° C. (roasting time). The color was set to be infused (around L20.5). The surface temperature of the coffee beans before roasting was 20 ° C.
[0048]
(1) Roasting time and roasting color [Table 1]

(2) Liquidity of the extract The coffee beans roasted in the above (1) are each crushed, put into an extractor (BONMAC NC1105), drip-extracted at a water ratio 18 times that of the crushed coffee beans, and the coffee extract is extracted. Obtained. The pH and absorbance of the extract were measured, and the results are shown in Table 2.
[0049]
[Table 2]

From Table 2, it was found that the longer the roasting time of the coffee, the higher the pH of the extract and the less turbidity (absorbance 720 nm).
[0050]
(3) Results of Gas Chromatography Analysis of Extract The total area of the peaks by gas chromatography was calculated and compared. Each peak was classified into three areas based on the column temperature at the time of analysis, and the peak area for each area was calculated. The composition of each component was examined.
[0051]
[Table 3]

[Table 4]

From Table 3, as the roasting time of the coffee becomes longer, the components having a high boiling point increase in the extract. Table 4 also shows that the longer the roasting time is, the less the irritating component is, and that the aftertaste has a crisp flavor. The shorter the roasting time, the lower the amount of pyridine, a component related to bitterness, and the higher the roasting time. Also, 2-methylfuran increases with the roasting time. It can be seen that the extract of coffee beans having a long roasting time contains a large amount of pyridine and 2-methylfuran, which are considered to be high in deeply roasted beans with strong bitterness. This indicates that the shorter the roasting time, the less the bitterness, and the longer the roasting time, the bitterness becomes.
[0052]
(4) Results of sensory evaluation Table 5 shows the results of evaluation of the extract by six expert panelists. The roasting time 10.0 minutes was evaluated as a reference (±).
[0053]
[Table 5]

According to Table 5, the sourness of the coffee extract is stronger as the roasting time is shorter, and weaker as the roasting time is longer. The bitterness and the richness are hardly sensual difference within 10 minutes, but tend to become stronger after 17 minutes.
[0054]
Example 2
Changes in taste and components when the roasting time in Colombia was changed Colombia EX was selected as the green coffee bean origin. The Columbia EX is put into a Probat small sample roaster (model: Br3P100), and roasting is performed by changing the time (roasting time) until the roasted bean surface temperature in the roasting machine reaches 208 ° C. ± 5 ° C. It was made to be infused (around L22.5). The surface temperature of the coffee beans before roasting was 21 ° C.
[0055]
The roasting machine, extraction conditions and measurement conditions of gas chromatography are the same as in Example 1.
[0056]
(1) Roasting time and roasting color [Table 6]

(2) Liquid properties of the extract [Table 7]

From Table 7, it can be seen that the longer the roasting time, the higher the pH of the coffee extract and the less turbidity (absorbance 720 nm). It can be seen that the change in pH in Colombia is smaller than that in Santos No. 4.
[0057]
(3) Results of gas chromatography analysis of the extract [Table 8]

[Table 9]

From Table 8, it can be seen that compared to Santos No. 4 of Example 1, even if the roasting time is longer, there is almost no change in the composition ratio by boiling point. Table 9 also shows that, as in Example 1, the longer the roasting time, the less the irritating component is, and the resulting aftertaste has a cut-off flavor. As with Santos No. 4, the amount of pyridine related to bitterness is smaller as the roasting time is shorter, and is larger as the roasting time is longer. It can be seen that the shorter the roasting time, the less the bitterness, and the longer the roasting time, the more bitter.
[0058]
(4) Sensory Evaluation Results Table 10 shows the results of the evaluation of the extract by six expert panelists. The roasting time 10.0 minutes was evaluated as a reference (±).
[0059]
[Table 10]

According to Table 10, the shorter the roasting time, the stronger the sourness, and the longer the roasting time, the weaker the sourness. The bitterness and richness are different from those of Santos No. 4, and the sensual difference is not felt small. Although the amount of pyridine in gas chromatography increases, the change is small, so that it is difficult to feel a sensory difference.
[0060]
Example 3
Changes in taste and components when the roasting time of Indonesian AP-1 was changed Robusta Indonesian AP-1 was selected as a coffee green bean origin. The Indonesian AP-1 was put into a small sample roaster (Pro: Br3P100) manufactured by Probat, and roasting was performed while changing the time (roasting time) until the surface temperature of the roasted beans in the roasting machine reached 225 ° C. ± 5 ° C. The same roasting color (about L21.5) was used. The surface temperature of the coffee beans before roasting was 23 ° C.
[0061]
The roasting machine, extraction conditions and measurement conditions of gas chromatography are the same as in Example 1.
[0062]
(1) Roasting time and roasting color [Table 11]

(2) Liquid properties of the extract [Table 12]

From Table 12, it can be seen that the longer the roasting time, the higher the pH of the coffee extract and the less turbidity (absorbance 720 nm). It can be seen that the change in pH of Indonesian AP-1 is smaller than that of Santos No. 4.
[0063]
(3) Results of gas chromatography analysis of the extract [Table 13]

[Table 14]

From Table 13, it can be seen from Table 13 that Indonesia AP-1 shows almost no change in the composition ratio by boiling point even when the roasting time is longer than that of Santos No. 4. Table 14 also shows that, as in Examples 1 and 2, the longer the roasting time, the less the irritating component is, and the resulting aftertaste has a cut off flavor. Similar to Santos No. 4, pyridine and 2-methylfuran also decrease as the roasting time is shorter and increase as the roasting time is longer. This indicates that the shorter the roasting time, the less the bitterness, and the longer the roasting time, the more the bitterness.
[0064]
(4) Sensory Evaluation Results Table 15 shows the results of the evaluation of the extract by six expert panelists. The roasting time of 9.3 minutes was evaluated as a reference (±).
[0065]
[Table 15]

According to Table 15, the sourness becomes stronger as the roasting time becomes shorter, and becomes weaker as the roasting time becomes longer. The bitterness and richness have a small sensory difference, but become stronger as the roasting time is longer. Although the pyridine content in the gas chromatography increased, unlike the case of Santos No. 4, the change was small, so the sensory difference was also small.

Claims (5)

In the method for producing roasted coffee beans including the step of roasting green coffee beans with hot air, the roasting time is changed by controlling the time required for the temperature of the roasted beans to reach a temperature selected from 200 to 235 ° C. A method characterized by enhancing the taste of beans. The method according to claim 1, wherein the green coffee beans are Robusta seeds, and the roasting time is less than 6 minutes to enhance the acidity of Robusta roasted beans. The method according to claim 1, wherein the green coffee beans are Arabica seeds, and the roasting time is 17 minutes or more to enhance the bitterness of the Arabica seed roasted beans. The method according to any one of claims 1 to 3, wherein the roasted color of the roasted coffee beans is medium-roasted with an L value of 20 to 26. The method according to claim 3 or 4, wherein the roasting time is 17 minutes or more, thereby producing a roasted bean supplying a less turbid extract.