JPS63141550A - Extraction and separation of coffee flavor essence - Google Patents

Abstract

PURPOSE:To extract and separate a high-quality coffee flavor essence having deep aroma from roasted coffee, by using carbon dioxide in a subcritical state as an extracting agent. CONSTITUTION:A coffee flavor essence is extracted and separated from roasted coffee. In the process, carbon dioxide in a subcritical state is used as an extracting agent and extraction is carried out stepwise in the extraction step or separation is fractionally performed in the separation step to dividedly collect the extracted component.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention provides a method for extracting and separating a coffee flavor extract having an excellent aroma from roasted coffee using subcritical carbon dioxide as an extracting agent. It is related to.

The obtained coffee flavor extract can be added to coffee products such as instant coffee and canned coffee that have few aromatic components, or to various other beverages and foods to create high-grade products containing natural coffee flavor with a good aroma. can be made.

(Prior Art and Problems to be Solved by the Invention) It is known to extract aromatic components from roasted coffee, but the method and problems are as described below.

First, there is a method of obtaining aroma components from roasted coffee at low pressure using steam or inert gas. in this case,
Since only highly volatile aromatic components are extracted,
If you try to use this extract later, most of the aromatic components will be lost and it will not serve as a flavor.

There is also a method of obtaining coffee oil containing aromatic components by an expression method using a screw press, etc., but in this method, roasted coffee is processed under high temperature and high pressure conditions during expression, resulting in chemical changes such as thermal decomposition. occurs, and the resulting coffee oil has a low grade aromaticity.

Another method is an extraction method using an organic solvent, but it is difficult to separate the aromatic components from the solvent, and the loss of highly volatile components or residual solvent poses a major problem.

There are also extraction methods using gaseous carbon dioxide and liquid carbon dioxide. These extraction methods can extract aroma components at relatively low pressure, but the solubility is low due to the low temperature, and especially in the case of extraction using liquid carbon dioxide, it is difficult to separate the aromatic components during solvent separation.
Requires heating energy.

Furthermore, Japanese Patent Publication No. 51-33185 describes an extraction method using carbon dioxide in a supercritical state. However, in the case of extraction using carbon dioxide in a supercritical state, substantially high temperature and high pressure conditions are required to carry out efficient extraction.

[Structure of the invention]

(Means for Solving the Problem) In view of the current situation, the present inventors have conducted various studies on a method for extracting a coffee flavor extract with an excellent aroma from roasted coffee, and have finally completed the book. The invention has been achieved.

That is, the present invention attempts to obtain a desired flavor extract from roasted coffee using subcritical carbon dioxide as an extraction agent.

A subcritical state is a subcritical state (Sub-(ri
It is also called the near-critical liquid state, and although there is no clear standard definition for it, it is generally defined as shown in Figure 1.
00〉Temperature (T)/R World Hot Water Temperature Tc%) It is universally understood to be the region of >0.95. For carbon dioxide, this corresponds to about 30°C to 16°C. This region is clearly not a Mi critical region (or a simple liquid phase region; it is a region where large changes and fluctuations in physical properties occur as a boundary region from a liquid phase region to a supercritical region, and it is extremely unstable. Moreover, it is a region that is activated in terms of properties, and is recognized as a remarkable region that is clearly different from the stable liquid phase and supercritical phase.

Carbon dioxide in the supercritical region is 31.0℃, 72.9a
It is in a state above the critical point of t@, has a density close to that of a liquid, and a large diffusion coefficient close to that of a gas, so it is characterized by the ability to quickly extract large amounts of various compounds and to easily separate the extractant. has. - Aged carbonic acid is produced by appropriately compressing gas cooled below a critical temperature. In this case, carbon dioxide in a supercritical state cannot be extracted in large quantities, but it can be operated at lower temperatures. It has the characteristic that only highly soluble substances are selectively extracted.

It is thought that this method combines the characteristics of each extraction method using carbonic acid.

Therefore, the purpose of extraction can be achieved economically and under relatively mild conditions. That is, the advantages of both increased extraction amount in supercritical carbon dioxide and partial extraction of non-volatile oily flavor substances and relatively mild conditions in liquefied carbonic acid are ensured. Also,
Surprisingly, it was discovered that by using subcritical carbon dioxide as an extractant, an extract with a higher quality and deeper aroma can be obtained compared to conventional methods. Further studies were conducted on extraction and separation conditions, etc., and the present invention was completed.

(Function) In the present invention, carbon dioxide in a subcritical state is used, but this is because carbon dioxide is easier to handle and operate than other flow paths, and is economically advantageous. This is because it has many advantages such as being inert, nonflammable, and nontoxic under certain conditions.

Hereinafter, embodiments of the present invention will be described based on a flow sheet. In FIG. 2, CO is made into a cylinder, brought to a subcritical state, and introduced into the extraction column 4.

The extraction tower 4 is charged with ground roasted coffee beans,
After the extraction is performed, the CO containing the extract is depressurized through the pressure reducing valve 5 and introduced into the separator 6, where the extract is extracted with CO.
Separate from t. The C08 separated from the extract is cooled and liquefied in a condenser 7, passed through a compressor, and recycled.

In the above process, it is necessary to maintain the pressure and temperature of 008 in the extraction column so that it is always in a subcritical state. It is also possible to perform stepwise extraction by introducing COt into the extraction column at a stepwise increase in pressure. Furthermore, it is also possible to perform semi-continuous operation by installing a plurality of extraction columns in parallel and switching between them.

-g, in the process shown in Figure 2, the extract is separated over time by the separator 6, but as the pressure is gradually lowered, the extract components will differ, so it is necessary to Depending on the component, it can be recovered by changing the method of fractionation. Namely.

It is also possible to install a plurality of separators in series and lower the pressure in stages to perform fractional separation and recovery.

In addition, when separating extracts over time using a separator,
Since the extract components obtained differ depending on the method of fractionation, it is also possible to perform fractional extraction of the desired component.

(Examples) Hereinafter, the present invention will be explained in more detail by showing Examples, but the present invention is not limited thereto.

Example 1 Using 500g of ground roasted coffee beans as a raw material, extraction was performed using COt at 150at end and 29°C as an extracting agent in the process shown in Figure 2, and the extract was separated at room temperature and atmospheric pressure.
18 g of extract was obtained.

This extract was light yellowish brown in color and had a high quality and deep aroma.

Example 2 1 kg of the same raw material used in Example 1 was extracted using Cot at 130 atm and 29°C as an extractant in the process shown in Figure 2, and the extract was extracted over time at room temperature and atmospheric pressure. Separation yielded three percentages.

Both portions initially obtained weighed 13 g. This was yellowish brown in color, had a relatively high viscosity, and contained a large amount of the highly volatile and pungent aroma contained in roasting tools. In the second percentile, a Log extract was obtained.

It was bright yellow in color, viscosity was large, and had a rounded aroma. The properties were almost the same as 100%, but the aroma was calmer and deeper.

〔Effect of the invention〕

According to the present invention, it is possible to industrially advantageously obtain a coffee flavor extract having an excellent aroma from roasted coffee, and the following excellent effects can be achieved compared to conventional methods.

(1) Until now, there has been no example of extracting aromatic substances from roasted coffee using subcritical carbon dioxide as an extracting agent (although it is revolutionary that a high-quality product can be easily extracted with the present invention). be.

(2) Since it can be extracted at a relatively low temperature and in an inert atmosphere, there is no risk of deterioration.

(3) Since the carbon dioxide used as the extractant evaporates rapidly during the separation process, there is no need to separate the solvent and the extract, unlike when a solvent is used as the extractant.

(4) The process is simple and selective separation and fractionation can be performed with high efficiency. For extracts obtained by fractionation, specific components are often concentrated in each fraction, and by re-blending them in an appropriate ratio according to preference, the desired aroma can be obtained.

(5) Compared to conventional extraction methods, by using subcritical carbon dioxide as an oil agent, a higher quality coffee flavor extract with a fragrant roasted aroma can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a graph showing the pressure-density relationship of carbon dioxide, and FIG. 2 is a flow sheet showing an example of an embodiment of the present invention.

Claims (2)

[Claims] (1) A method for extracting and separating coffee flavor extract, which is characterized by using carbon dioxide in a subcritical state as an extraction agent in extracting and separating coffee flavor extract from roasted coffee. (2) In the extraction process, by performing extraction stepwise or in the separation process, performing fractional separation,
The method according to claim (1), wherein the extracted components are obtained by dividing them.