JP5833841B2 - Production method of coffee extract - Google Patents

Description

  The present invention relates to a method for producing a coffee extract, which relates to a production method having a high yield of soluble solids derived from coffee beans.

  It is desirable that the coffee extract used in the container-packed coffee beverage has a rich aroma and flavor unique to coffee, a rich taste and sweetness so as to be suitable for drinking with black (sugar-free or fine sugar), and such characteristics Various methods for producing a coffee extract having the above have been studied.

  Patent Document 1 relates to a method for producing a concentrated coffee extract. A slurry is prepared by wet-grinding roasted coffee beans, and an aroma component-containing condensate is separated from the stripped slurry by a stripping process, and further obtained. The slurry is separated into solid and liquid and separated into sludge, coffee oil-containing liquid and coffee extract. However, there is no description about the rich taste of the obtained extract or the soluble solid content extraction rate of the pre-concentration coffee extract.

  Patent Document 2 discloses a method for producing a coffee extract having sweetness and richness by performing an enzyme treatment on a slurry after a stripping treatment. However, the yield of soluble solids is only 38% at the maximum, and there is also a problem that process management becomes complicated when the slurry is treated with an enzyme.

  Patent Document 3 discloses that raw coffee beans are wet-heated and roasted by high-temperature and high-pressure treatment, and the obtained roasted coffee beans are pulverized and then allowed to act on plant polysaccharide-degrading enzymes. Is disclosed. According to this method, the yield of soluble solids of coffee beans reaches a maximum of 50.4%, but the composition and aroma of the obtained extract are not described.

WO2006 / 028193 JP 2009-278957 A JP 2004-121138 A

  As described above, in the production of a coffee extract, improvement of extraction efficiency of soluble solids derived from coffee beans is a problem. Improving the extraction efficiency of soluble solids by direct enzyme treatment of the slurry can be expected, but since the substrate is solid, it can be used for optimization of reaction conditions, measurement of reaction progress, temperature control during reaction, stirring work, etc. There's a problem. Moreover, in order to obtain higher extraction efficiency, there is also a problem that it is necessary to use a plurality of enzymes in combination.

  An object of the present invention is to provide a method for producing a fragrant coffee extract having a high yield of soluble solids derived from coffee beans.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have surprisingly found that the slurry after stripping treatment is subjected to continuous high-temperature treatment before solid-liquid separation, and sludge and coffee extract, coffee oil After the separation, the extraction of soluble solids derived from coffee beans is improved by treating the resulting coffee extract with a polysaccharide-degrading enzyme, and the low molecular sugar in the coffee extract is increased. The present invention has been completed.

That is, the present invention includes, but is not limited to, the following inventions.
(1) A method for producing a coffee extract, the step of pulverizing roasted beans, the step of stripping the obtained pulverized beans, the step of treating the resulting slurry at a temperature of 100 to 180 ° C., from the processed product The said manufacturing method including the process of isolate | separating a coffee extract, and the process of processing the obtained coffee extract with a polysaccharide-degrading enzyme.
(2) The production method according to (1), comprising a concentration step and a step of removing aggregates after the enzyme treatment step.
(3) The production method according to (1) or (2), wherein a centrifuge is used in the separation step and the aggregate removal step.
(4) The production method according to any one of (1) to (3), wherein the polysaccharide-degrading enzyme is one or more selected from the group consisting of cellulose-degrading enzyme, hemicellulose-degrading enzyme, and pectinase.

  The coffee extract obtained by the method of the present invention has a unique aroma of coffee, and also has sweetness and richness. Therefore, it can be suitably drunk as black coffee (sugar-free or fine sugar), and can also be suitably used in other forms such as coffee drinks with milk and coffee jelly.

FIG. 1 shows the results of analysis using each molecular weight sample and shows the relationship between retention time and molecular weight. FIG. 2 shows the results of analyzing polysaccharides in the coffee extract obtained under each processing condition. FIG. 3 shows the results of analyzing polysaccharides in the clarified coffee extract obtained under each processing condition.

  The present invention provides a method for producing a coffee extract, which provides a high yield of soluble solids derived from coffee beans. The method of the present invention includes a step of pulverizing roasted beans, a step of stripping the obtained pulverized beans, a step of treating the resulting slurry at a temperature of 100 to 180 ° C., a step of separating the coffee extract from the processed product, And a step of treating the resulting coffee extract with a polysaccharide-degrading enzyme.

The embodiment of the present invention will be described in more detail.
<Crushing roasted beans>
The coffee beans to be used may be obtained by any method as long as they are roasted coffee beans. As varieties of coffee beans, Arabica, Robusta, Revelica and the like can be used, and particularly Arabica and Robusta can be preferably used. In addition, the beans to be used can be used by mixing a plurality of beans with different origins, varieties, and roasting degrees.

  As a roasting machine for green coffee beans, a general roasting machine (horizontal drum type roasting machine) can be used, and roasting methods can be classified into heating methods, such as direct fire, hot air, far infrared rays, A microwave or the like can be used. In addition, roasting degree is an 8-stage designation of the US method, and can be used for any of light roast, cinnamon roast, medium roast, high roast, city roast, full city roast, French roast, and Italian roast. .

  For grinding of roasted beans, either dry grinding or wet grinding can be used. When dry grinding is used, a slurry is prepared by adding water after grinding, and when wet grinding is used, it is ground after adding water to roasted beans. To prepare a slurry. As the pulverizer, Fitzmill (manufactured by FITZPATRICK), Komitrol (manufactured by Archer) or the like can be used. For hydration, tap water, ion-exchanged water, deoxygenated water, pure water, ground water and the like can be used, and stabilizers, pH adjusters and the like can be added to these waters.

  The weight ratio of coffee beans to water is preferably 1: 3 to 1: 100, more preferably 1: 5 to 1:50, and still more preferably 1: 5 to 1:20. Most preferably, it is 1:10.

  In addition, it is preferable to use wet pulverization from the viewpoint of preventing temperature rise and fragrance scattering during pulverization. In that case, water is continuously added during pulverization so that the final ratio of beans and water becomes the above ratio. It is preferable to do.

The ground particle size of coffee beans is preferably 0.1 mm to 4 mm, more preferably 0.1 mm to 2 mm. The average pulverized particle size of the pulverized coffee beans can be measured using, for example, a low-tap sieve shaker (manufactured by Tanaka Tech Co., Ltd.).
<Stripping process>
The obtained slurry is stripped to recover the aroma component-containing condensate. The stripping treatment is a treatment for concentrating volatile components in the slurry into a gas phase by bringing the heat source and the slurry into countercurrent contact and performing rectification. In the present invention, SCC (Spinning Cone Column, manufactured by Flavor Tech) or the like can be used.
<High temperature treatment of slurry>
The stripped slurry is then subjected to a high temperature treatment. The continuous high-temperature treatment after stripping partially decomposes the cell wall of the ground coffee beans, leading to an improvement in the extraction efficiency of soluble components. From the viewpoint of improving extraction efficiency, the processing temperature is preferably 100 to 180 ° C, more preferably 120 to 180 ° C, and most preferably 150 to 180 ° C. From the viewpoint of maintaining flavor, the treatment temperature is preferably 100 to 180 ° C, more preferably 100 to 150 ° C, and most preferably 100 to 120 ° C. Considering the balance between extraction efficiency and flavor retention, the treatment temperature is preferably 110 to 160 ° C, and most preferably 120 to 150 ° C. The treatment time is preferably 10 to 30 minutes, more preferably 15 to 25 minutes.
<Solid-liquid separation of slurry>
The slurry that has undergone the stripping treatment and the high-temperature treatment is separated into coffee mash and coffee extract by solid-liquid separation. The separation method is not particularly limited, and coarse filtration, vibration sieve, screw press, screw decanter, and the like can be used as appropriate. However, it is convenient in operation to perform solid-liquid separation by centrifugation. As the centrifuge, for example, FOODEC300 (manufactured by Alfa Laval) can be used.

Since the obtained coffee extract contains fine powder and oil, it is further separated by centrifugation into three layers of insoluble fine particles (sludge), coffee oil, and coffee extract. For example, CRPX918 or AFPX407 (manufactured by Alfa Laval) can be used as the centrifuge.
<Enzyme treatment>
Since the coffee extract after the three-layer separation contains a large amount of polysaccharide, it is decomposed by a polysaccharide-degrading enzyme. As the enzyme, cellulose degrading enzyme, hemicellulose degrading enzyme, or pectinase can be used, and a plurality of enzymes can be used in combination. In order to increase the ratio of oligosaccharides, it is desirable to use a single enzyme. Viscozyme (manufactured by NOVOZYMES) is known as a commercially available enzyme agent containing these enzyme activities. For example, when this enzyme is used, it can be expressed in coffee extract using FBG, which is an indicator of the activity of this enzyme. The enzyme may be added to 0.1 to 100 FBG / l. In addition, what is necessary is just to add each enzyme activity corresponding to the said usage-amount of a biscozyme, when using a cellulose decomposing enzyme, a hemicellulose decomposing enzyme, or pectinase individually or in combination. The enzyme-added coffee extract is reacted at 25 to 65 ° C. for 30 to 360 minutes. The enzyme concentration in the coffee extract is preferably 1 to 50 FBG / l, and more preferably 5 to 15 FBG / l. The reaction temperature is preferably 35 to 60 ° C, and preferably 45 to 55 ° C. The reaction time is preferably 60 to 240 minutes, and preferably 120 to 180 minutes.

The enzyme-treated extract is subjected to heat treatment at 95 ° C. for 1 to 300 seconds for enzyme deactivation.
<Concentration>
For concentration of the coffee extract, a centrifugal thin film concentrator, a flash evaporator, a thin film descending vacuum evaporator, a freeze concentrator, a reverse osmosis membrane concentrator, etc. can be used. For example, Centritherm CT-12 (Flavor Tech) Can be used. As for the degree of concentration, it is preferable to use Brix as an index, and to end the concentration step when Brix reaches 30 to 40 degrees.
<Clarification>
Since fine components and polysaccharide-degrading enzymes aggregate due to concentration, they are removed by centrifugation. As the centrifuge, CRPX918 (manufactured by Alfa Laval) can be used. Moreover, you may perform the filtration process by a microfiltration membrane etc. before and / or after centrifugation as needed.

The clarified coffee extract thus obtained can be used as a container-packed beverage as it is, or after adding milk, sugar, emulsifier, etc., and adding aroma condensed extract, coffee oil, and the like.
<Analysis of polysaccharides>
The polysaccharide in the coffee extract can be measured, for example, by the following liquid chromatographic analysis.

For example, after adjusting the Brix of the measurement sample to 0.25% and filtering with a 0.45 μm filter, the measurement is performed using the following analyzer and conditions.
Analyzer: Agilent 1100Series
Detector: RI
Column: Shodex Asahipak GS-520 HQ
Precolumn: Shodex Asahipak GS-2G 7B
Mobile phase: Ultrapure water Liquid flow rate: 0.5ml / min
Analysis time: 40 minutes
Injection volume: 10.00μl
Column temperature: 40 ° C

EXAMPLES Hereinafter, although this invention is demonstrated based on an Example, this invention is not limited to these Examples.
Example 1
Each sample was prepared by the following method.
・ Comparative sample 1
A coffee extract was produced without high-temperature treatment of the stripped slurry. That is, Arabica coffee roasted to an average L value of about 20 was ground with 9 times its amount of pure water to prepare a coffee slurry, and then stripped using SCC. The stripping process was performed so that the steam for stripping was 30 KG / h with respect to 600 KG / h of the coffee slurry. The coffee slurry after the stripping process is processed into a solid-liquid separation with a screw decanter and a centrifugal separator AFPX407 (Alfa Laval) capable of separating three layers under the condition of 60 KG / h to separate the fine particle component and the oil, and clarify A coffee extract was obtained.
-It carried out according to the method of the said comparative sample 1 except carrying out the high temperature process of the slurry after stripping.

  The high temperature treatment was performed under the following conditions. i) The stripped coffee slurry is treated with RDC (Rotating Disc Column: FlavorTech) at 120 ° C. for 20 minutes, ii) The stripped coffee slurry is treated with RDC at 150 ° C. for 20 minutes, iii) Coffee after stripping Treat the slurry with RDC at 180 ° C. for 20 minutes.

  FIG. 1 shows the relationship between retention time and molecular weight by separately measuring molecular weight markers having molecular weights of 180, 500, 1000, 2000, 5000, 10000, 20000, and 80000. The analysis conditions are shown below.

Analyzer: Agilent 1100Series
Detector: RI
Column: Shodex Asahipak GS-520 HQ
Precolumn: Shodex Asahipak GS-2G 7B
Mobile phase: Ultrapure water Liquid flow rate: 0.5ml / min
Analysis time: 40 minutes
Injection volume: 10.00μl
Column temperature: 40 ° C
The Brix of the measurement sample was adjusted to 0.25%, filtered through a 0.45 μm filter, and then measured using the above-described analyzer and conditions. FIG. 2 shows the results of analyzing the polysaccharides of the coffee extract obtained without the high temperature treatment (Comparative Sample 1) and with the treatment temperatures of 120 ° C., 150 ° C., and 180 ° C. The shorter the retention time, the higher the molecular weight, and the higher the temperature of the slurry, the more the polysaccharides with a molecular weight of 100,000 or more, the polysaccharides with a molecular weight of 5000 to 100,000, and the polysaccharides with a molecular weight of 180-500 are increasing. I understand. In particular, it can be seen that polysaccharides having a molecular weight of 180 to 500 are specifically increased when subjected to a high-temperature treatment at 180 ° C. These peaks are thought to contain monosaccharides or disaccharides.

  The amounts of soluble solid components derived from coffee beans contained in these extracts are as shown in Table 1.

Thus, it can also be seen that the extraction rate of the soluble solid component is improved by the high temperature treatment of the slurry.
Example 2
The coffee extract of Comparative Sample 1 in Example 1 was concentrated to Brix 30 with a vacuum thin film evaporating and concentrating apparatus at 40 ° C. without any enzyme treatment, and then subjected to three-layer centrifugation to remove fine particles and oil. A clarified coffee extract was produced (Comparative Sample 2).

  Viscozyme L is added to the coffee extract of Comparative Sample 1 so that the coffee soluble solid content is 0.3%, and after 3 hours of enzyme treatment at 50 ° C., heat treatment is performed at 95 ° C. for 60 seconds. The enzyme was inactivated, and after concentration, three-layer centrifugation was performed to remove fine particles and oil, thereby producing a clarified coffee extract (Comparative Sample 3).

  The coffee extract obtained by the method including the high-temperature treatment of Example 1 was subjected to enzyme treatment in the same manner as the preparation method of Comparative Sample 3, and then the enzyme was deactivated and concentrated, and then subjected to three-layer centrifugation to obtain fine particles and The oil was removed and a clarified coffee extract was produced. (Example 2 (120 degreeC, 150 degreeC, 180 degreeC)).

The result of having analyzed the polysaccharide in the clarified coffee extract of the comparative sample 2, the comparative sample 3, and Example 2 (120 degreeC, 150 degreeC, 180 degreeC) is shown in FIG.
As can be seen from FIG. 2, the sample of Example 2 in which the slurry after stripping was treated at a high temperature had a peak with a molecular weight of about 180 higher than those of Comparative Sample 2 and Comparative Sample 3. Considering the molecular weight, this peak is considered to be a monosaccharide.
Example 3
A coffee beverage using the obtained coffee extract was produced and subjected to a sensory evaluation test. Sensory evaluation was performed by 4 trained panelists. The evaluation method was performed by diluting each to about 1.5 degrees of Brix, and as evaluation items, sweetness, richness, and sourness were evaluated in a range of 1 to 5 points. An evaluation method was adopted in which the sweetness, richness, and sourness of Comparative Sample 2 was set to 3.0, the score was lowered when the strength was weakened, and the score was raised when the strength was strengthened. The average score is shown in Table 2.

  ADVANTAGE OF THE INVENTION According to this invention, the yield of the soluble solid content derived from coffee beans is high, and the method of manufacturing a fragrant coffee extract is provided. The coffee extract obtained by the method of the present invention has a unique aroma of coffee, and also has sweetness and richness. Therefore, it can be suitably drunk as black coffee (sugar-free or fine sugar), and can also be suitably used in other forms such as coffee drinks with milk and coffee jelly.

Claims (4)

A method for producing coffee extract,
Crushing roasted beans,
A step of stripping the resulting ground beans,
A step of treating the resulting slurry at a temperature of 150 to 180 ° C .;
Separating the coffee extract from the temperature-treated slurry , and treating the resulting coffee extract with a polysaccharide-degrading enzyme;
The said manufacturing method including.   The manufacturing method of Claim 1 including the process of removing a concentration process and an aggregate after an enzyme treatment process.   The production method according to claim 1 or 2, wherein a centrifuge is used in the separation step and the aggregate removal step. The production method according to any one of claims 1 to 3, wherein the polysaccharide-degrading enzyme is one or more selected from the group consisting of a cellulolytic enzyme, a hemicellulose degrading enzyme, and a pectinase.