JP2008022751A - Coffee extract liquid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently provide coffee extract liquid having favorable coffee flavor and rich in chlorogenic acid. <P>SOLUTION: The coffee extract liquid is obtained by extracting coffee beans roasted in nitrogen atmosphere and having an L value of 20.5-30.5, and has (A) chlorogenic acid/Brix of 0.11-0.19. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a coffee extract containing a high concentration of chlorogenic acids per solid, wherein coffee beans are roasted in a nitrogen atmosphere and then extracted.

  In recent years, catechins and chlorogenic acids having an antioxidant function widely present in foods are attracting attention as food materials for preventing lifestyle-related diseases. There are many chlorogenic acids as polyphenols in coffee, and as one of the intake effects, chlorogenic acid, caffeic acid, ferulic acid, etc. contained in foods such as coffee show excellent blood pressure lowering action (Patent Documents 1 to 3).

Therefore, in the development of products using coffee polyphenols, how to secure a high concentration of chlorogenic acids in coffee is an important problem in production.
On the other hand, it is known that considerable chlorogenic acids disappear due to roasting even though coffee beans contain many chlorogenic acids (Non-patent Document 1). Therefore, in order to secure a high concentration of chlorogenic acids, a production method using raw bean extract or low roasted coffee beans is also conceivable. However, in this case, there was a raw odor derived from green beans, which was a cause of a decrease in the flavor of the coffee product.
As a known technique for roasting coffee beans, there is a heat processing method for coffee or peanuts (Patent Document 4), but the known technique prevents air oxidation during heating and preserves the original taste of the food. It is what. As a method for performing the known technique, the object to be heated is housed in a container that shuts off outside air, and the oxygen-free gas is recycled with an oxygen scavenger in the container or the gas is recycled. Is what you do.
However, the present invention is fundamentally different from the known technique in that it does not attempt to preserve the original taste of the food. In addition, in the known technique, only oxidative alteration of lipids is described.
Moreover, although there exists the roasting method of low oxygen roasted coffee beans, and its manufacturing method (patent document 5), it was not satisfactory as a packaged drink from a viewpoint of flavor and taste.
JP 2002-363075 A JP 2002-22062 A JP 2002-53464 A JP 54-122754 A JP 2003-274862 A Coffee roasting chemistry and technology (Toshiro Nakabayashi et al., Hirogaku Publishing)

  An object of the present invention is to efficiently produce a coffee extract rich in chlorogenic acid and having a good coffee flavor.

Therefore, as a result of examining various roasting conditions for coffee beans, the present inventor conducted roasting of coffee beans in a nitrogen atmosphere, and the coffee extract from which the roasted beans were extracted was roasted beans in the presence of air. As compared with the case where it is used, the present inventors have found that a chlorogenic acid is present in a high concentration and that a coffee extract having a good flavor without a raw odor can be obtained, thereby completing the present invention.
That is, the present invention is roasted under a nitrogen atmosphere, extracted from coffee beans having an L value of 20.5 to 30.5, and (A) coffee extraction having chlorogenic acids / Brix of 0.11 to 0.19. It is a liquid.

  In the present invention, the coffee extract having an L value of 20.5 to 30.5 of roasted beans performed in a nitrogen atmosphere has a higher content of chlorogenic acids than those of the same L value performed in the presence of air. Moreover, it discovered that flavor was also favorable.

  If the manufacturing method of this invention is used, a chlorogenic acid-rich coffee drink with favorable flavor can be provided.

In the present invention, a method similar to normal roasting may be used except that roasting of coffee beans is performed in a nitrogen atmosphere and roasting is performed so that the L value is kept within 20.5 to 30.5. In addition, L value said by this invention is a value which shows the roasting degree measured with the color difference meter by the normal well-known method.
Although the kind of coffee bean is not specifically limited, For example, Brazil, Colombia, Tanzania, Mocha, Kilimangelo, Mandelin, Blue Mountain etc. are mentioned. Coffee beans include Arabica and Robusta. One kind of coffee beans may be used, or a plurality of kinds may be blended. There are no particular restrictions on the method of making coffee beans roasted by roasting, and there are no restrictions on the roasting temperature and roasting environment.
In the present invention, roasting of coffee beans is performed in a nitrogen atmosphere, and roasting is performed so that the L value is kept within 20.5 to 30.5. If roasting is performed until the L value is outside this setting range, an increase in the content of chlorogenic acid cannot be expected.
In the present invention, under nitrogen atmosphere, specifically, the nitrogen content in the roasting atmosphere is 90 to 100% by volume, preferably 95 to 100% by volume, and more preferably 98 to 100% by volume. Say the atmosphere.
Moreover, as a preferable range of roasting degree, L value is 20.5-30.5, Preferably it is 21-28, More preferably, it is 22-26.
The range of (A) chlorogenic acids / Brix in the extract is 0.11 to 0.19, preferably 0.12 to 0.18, and more preferably 0.13 to 0.16. Within this range, a coffee extract that is sour and easy to drink can be obtained.

Furthermore, there is no restriction | limiting also about the extraction method from the bean, For example, the method of extracting from a roasted coffee bean or its ground material using water-hot water (0-100 degreeC) for 10 second-30 minutes is mentioned. Examples of the extraction method include a boiling type, an espresso type, a siphon type, and a drip type (paper, flannel, etc.).
At this time, the roasted coffee beans or the pulverized product thereof can be extracted by their weight: water = 1: 2 to 1:16 (water to hot water). The pH of the water used at that time can be implemented in the range of 5.0-7.8.

The extraction conditions from the coffee beans of the present invention refer to those using 1 g or more of coffee beans in terms of green beans per 100 g of the extract. Preferably, 2.5 g or more of coffee beans are used. More preferably, 5 g or more of coffee beans are used.
The solid content concentration in the coffee extract is preferably 0.1 to 5.0% by weight from the viewpoint of flavor.

  The chlorogenic acids in the present invention include three kinds of monocaffeoylquinic acid, ferulacinic acid, and dicaffeoylquinic acid. Here, the monocaffeoylquinic acid includes one or more selected from 3-caffeoylquinic acid, 4-caffeoylquinic acid, and 5-caffeoylquinic acid. Further, examples of ferulquinic acid include one or more selected from 3-ferlaquinic acid, 4-ferlaquinic acid and 5-ferlaquinic acid. Examples of dicaffeoylquinic acid include one or more selected from 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, and 4,5-dicaffeoylquinic acid. The content of the chlorogenic acids can be measured by high performance liquid chromatography (HPLC). As a detection means in HPLC, UV detection is generally used, but it can also be detected with higher sensitivity by CL (chemiluminescence) detection, EC (electrochemical) detection, LC-MS detection, or the like.

  The coffee extract obtained by the present invention can be applied to coffee compositions, instant coffee compositions, and coffee beverages.

The concentration of chlorogenic acid in the extract is preferably 223 mg / 100 ml to 3160 mg / 100 ml, more preferably 230 mg / 100 ml to 2800 mg / 100 ml, and particularly preferably 250 mg / 100 ml to 2550 mg / 100 ml. If the concentration is within this range, it is easy to prepare and control a coffee beverage with good flavor.
The form of instant coffee using the coffee composition of the present invention may be liquid, gel, or solid. As the solid form, granules, tablets, powders and the like can be selected.
When preparing a coffee beverage using a coffee composition, the liquid coffee composition can be prepared by heating or after being diluted or dissolved with water (including hot water). it can. The solid coffee composition can be diluted or dissolved with water (including hot water) to prepare a coffee beverage.

  If desired, the coffee beverage of the present invention may be added with sugars such as sucrose, glucose, fructose, xylose, fructose glucose solution, sugar alcohol, milk components, antioxidants, pH adjusters, emulsifiers, fragrances and the like. it can. Examples of the milk component include raw milk, cow milk, whole milk powder, skim milk powder, fresh cream, concentrated milk, skimmed milk, partially skimmed milk, and milk. The pH of the coffee beverage of the present invention is preferably 3 to 7.5, more preferably 4 to 7, and particularly preferably 5 to 7 in terms of beverage stability.

The coffee beverage of the present invention is preferably a sterilized containerized coffee beverage.
The heat sterilization treatment of the container-packed coffee beverage is performed under the sterilization conditions defined in the Food Sanitation Law if it can be heat sterilized after filling a container such as a metal can. For items such as PET bottles and paper containers that cannot be sterilized by retort, sterilize under the same conditions as those prescribed in the Food Sanitation Law in advance. The method of filling a container etc. is mentioned.

  Examples of the container of the container-packed coffee beverage of the present invention include PET bottles, cans (aluminum, steel), paper, retort pouches, bottles (glass) and the like.

<Analytical method of chlorogenic acids>
The analysis method of chlorogenic acids in the coffee composition and coffee beverage is as follows. The analytical instrument used was HPLC. The model numbers of the unit units are as follows. UV-VIS detector: L-2420 (Hitachi High-Technologies Corporation), column oven: L-2300 (Hitachi High-Technologies Corporation), pump: L-2130 (Hitachi High-Technologies Corporation), autosampler: L-2200 (Hitachi High-Technologies Corporation), column: Cadenza CD-C18 inner diameter 4.6 mm × length 150 mm, particle diameter 3 μm (intact Inc.).

  The analysis conditions are as follows. Sample injection volume: 10 μL, flow rate: 1.0 mL / min, UV-VIS detector set wavelength: 325 nm, column oven set temperature: 35 ° C., eluent A: 0.05 M acetic acid, 0.1 mM 1-hydroxyethane-1 , 1-diphosphonic acid, 10 mM sodium acetate, 5 (V / V)% acetonitrile solution, eluent B: acetonitrile.

Concentration gradient condition Time Eluent A Eluent B
0.0 minutes 100% 0%
10.0 minutes 100% 0%
15.0 minutes 95% 5%
20.0 minutes 95% 5%
22.0 minutes 92% 8%
50.0 minutes 92% 8%
52.0 minutes 10% 90%
60.0 minutes 10% 90%
60.1 minutes 100% 0%
70.0 minutes 100% 0%

  In HPLC, 1 g of a sample was precisely weighed, made up to 10 mL with eluent A, filtered through a membrane filter (GL chromatodisc 25A, pore size 0.45 μm, GL Sciences Inc.), and subjected to analysis.

Retention time of chlorogenic acids (unit: minutes)
Monocafe oil quinic acid: 5.3, 8.8, 11.6, 3 points in total; Ferlaquinic acid: 13.0, 19.9, 21.0, 3 points in total, Dicafe oil quinic acid: 36. 6, 37.4, 44.2, 3 points in total. From the area values of the nine types of chlorogenic acids determined here, 5-caffeoylquinic acid was used as a standard substance, and the mass% was determined. Note that instant coffee was appropriately diluted with water and analyzed in the same manner.

<Brix measurement>
Brix was measured at 20 ° C. using a digital refractometer RX-5000 (Atago Co., Ltd.).

<Color difference meter measurement>
The roasted beans were finely ground in a coffee mill (Kalita), then packed in an analysis cell, and the L value was measured with Spectro color 2000 (NIPPON DENSHOKU).

Example 1 (Preparation of roasted coffee under nitrogen atmosphere)
120 g of commercially available green coffee beans (Colombia EX) were charged into a roaster MR-101 installed in a nitrogen atmosphere, and after the inside of the roaster was sufficiently replaced with nitrogen, roasting was performed at an arbitrary roasting time. When the coffee beans returned to room temperature after roasting, they were pulverized with a coffee mill, and the pulverized product was measured for L value with a color difference meter (L value 23.8).
Extraction was performed by adding 520 g of hot water to 65.0 g of the pulverized product (stirring at 95 ° C. and about 300 rpm for 30 minutes). After extraction, the mixture was filtered through a GAF (5 μm) filter to obtain 318 g of an extract (Brix 3.62).
Using this extract, a Brix 2% coffee beverage was prepared, and chlorogenic acids were measured.
Specifically, the chlorogenic acids of the coffee beans (L value 23.8) were 296.4 mg / 100 g (chlorogenic acids / Brix = 0.15) under a nitrogen atmosphere.
The yield of chlorogenic acids per solid was higher in the nitrogen atmosphere than in the presence of air.

Comparative Example 1 (Preparation of roasted bean extract in the presence of air)
120 g of commercially available green coffee beans (Colombia EX) were charged into a roaster MR-101 (manufactured by Dainichi Kogyo Co., Ltd.) and roasted at an arbitrary roasting time. When the coffee beans returned to room temperature after roasting, they were pulverized by a coffee mill, and the pulverized product was measured for L value with a color difference meter (L value 23.8). Extraction was performed by adding 525 g of hot water to 65.6 g of the pulverized product (stirring at 95 ° C. and about 300 rpm for 30 minutes). After extraction, the mixture was filtered through a GAF (5 μm) filter to obtain an extract of Brix 3.61% and 335 g. Using this extract, a Brix 2% coffee beverage was prepared, and chlorogenic acids were measured. The concentration of chlorogenic acids in a coffee beverage prepared from an extract of coffee beans (L value 23.8) roasted by a normal roasting method (in the presence of air) is 249.4 mg / 100 g (chlorogenic acids / Brix) = 0. .13.

  Including Comparative Example 1 and Example 1, coffee beans having various roasting degrees in the presence of air and in a nitrogen atmosphere were prepared, and chlorogenic acids in the extract were measured. In FIG. 1, the L value of these coffee beans and the chlorogenic acids (CGA) / Brix ratio were plotted.

Example 2 (Preparation of flavor evaluation coffee)
Using the coffee extract prepared in Comparative Example 1 and Example 1, the can was filled with a coffee composition prepared to pH 5.4 and Brix 2%, wound and wrung, and then subjected to retort sterilization at 123 ° C. for 10 minutes. A coffee beverage for flavor evaluation was used.

Flavor comparison of coffee prepared in the presence of air and coffee prepared under nitrogen atmosphere The flavor evaluation (panel: 5 persons) of the coffee prepared in Example 2 was performed.
Prepared coffee in a nitrogen atmosphere Prepared coffee in the presence of air “easy to drink” 40% 20%
"Sour" 40% 20%
The roasted product in a nitrogen atmosphere has an “easy to drink” flavor that is relatively rich in acidity.

Example 3 (Preparation of instant coffee)
The roasted coffee extract obtained in Example 1 was freeze-dried under a nitrogen atmosphere to obtain instant coffee.
The coffee after dissolving the obtained coffee powder also had good flavor.

It is a graph which shows the relationship between L value of a roasted coffee bean performed in presence of air and nitrogen atmosphere, and chlorogenic acid (CGA) / Brix ratio.

Claims (8)

Roasted in a nitrogen atmosphere, extracted from coffee beans having an L value of 20.5 to 30.5, and (A) a coffee extract having chlorogenic acids / Brix of 0.11 to 0.19. The coffee extract according to claim 1, wherein the amount of (B) chlorogenic acids in the coffee extract is 223 mg / 100 ml to 3160 mg / 100 ml. The coffee extraction liquid according to claim 1 or 2, wherein the extraction method is a boiling type, an espresso type, a siphon type or a drip type. The coffee extract according to any one of claims 1 to 3, wherein in the extraction, the weight ratio of coffee beans to water is 1: 2 to 1:16. In extraction, the pH of water is 5.0-7.8, The coffee extract of any one of Claims 1-4. The instant coffee composition manufactured from the coffee extract of any one of Claims 1-5. The coffee drink which mix | blended the coffee extract of any one of Claims 1-5. A packaged coffee beverage filled with the coffee beverage according to claim 7.

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