JP2003289805A - Method for roasting coffee bean - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for roasting arabica variety of high-grade coffee beans having favorable aroma without spoiling its original flavor. <P>SOLUTION: This method for roasting coffee beans comprises heating arabica variety of coffee beans at a roasting temperature for a predetermined period of time followed by cooling the heated coffee beans with a suction fun in a drying atmosphere at a cooling rate of 2.5°C/min or less without using cooling water. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for roasting coffee beans, and more particularly to a method for roasting coffee beans having high aroma by cooling coffee beans composed of Arabica seeds at a predetermined cooling rate.

[0002]

2. Description of the Related Art Conventionally, coffee beans that are commercially roasted are produced by placing green coffee beans (hereinafter sometimes simply referred to as "green beans") in a rotary roasting device and separately providing a heat source. This is done by sending hot air to the roasting device.
When raw beans change to a predetermined roasted color by being heated,
It is rapidly cooled (quenching) by cooling water. The quenched coffee beans are sent to the next step while being fixed to a predetermined roasting color (also referred to as roasting degree) without further progressing in a direction in which the roasting color darkens.

However, it is unavoidable that the aroma component possessed by the coffee beans is scattered by quenching, and the cooling water that has been introduced contacts the roasted coffee beans and becomes hot water or steam. However, a part of it goes inside the roasted beans, and by taking in the aroma components, this results in discharging the aroma components of the coffee beans to the outside of the beans, and it is supposed to reduce the flavor of coffee beans. It was

Therefore, various methods have been developed so as to prevent such aroma components from escaping to the outside as much as possible.
For example, a method using a small amount of water and using dry ice or liquid nitrogen (Japanese Patent Laid-Open No. 56-96664), and a method using high-temperature high-pressure steam to improve the flavor of lower beans such as Robusta seeds (Japanese Patent Laid-Open No. Hei 9 (1999) -26498) 3-160948
(Japanese Patent Laid-Open No. 2-177857) and the like, in which the water content of roasted beans is adjusted in advance and then roasted.

[0005]

However, even if dry ice or liquid nitrogen is used, the use of water, albeit in a small amount, still deprives the aroma component of coffee beans, and high temperature and high pressure steam is used. The method of roasting and roasting beans by adjusting the water content of the roasted beans in advance is a high-grade Arabica type that can be adopted as a method of improving the "earthy" flavor of low-grade Robusta type coffee beans. For coffee beans, it is not a suitable method to use because it will impair its high quality flavor.

Therefore, in view of the above problems of the prior art, an object of the present invention is to roast an arabica coffee bean having high quality and good aroma characteristics without impairing the flavor to obtain a good roasting property. It is to provide a method for obtaining roasted beans.

[0007]

The above objects can be achieved by the inventions described in the claims. That is, the characteristic configuration of the method for roasting coffee beans according to the present invention is that coffee beans made of Arabica seeds are heated at a roasting temperature for a predetermined time, and then at least by a suction fan in a dry atmosphere without using cooling water, It is to cool at a cooling rate of 2.5 ° C./second or less.

According to this construction, after the roasting is completed and taken out and cooled by the suction fan without using any cooling water, the excellent aroma component of Arabica coffee beans is escaped into the cooling water. However, the degree of roasting does not significantly progress and the commercial value is not significantly reduced. As a result, a method for roasting can be provided without impairing the flavor of Arabica coffee beans having high quality and good aroma characteristics.

The cooling is performed to 35 to 50 ° C. for 1.0 to 2.
It is preferable to cool the roasted coffee beans at a cooling rate of 0 ° C./sec and to keep the water content of the roasted coffee beans at 3.0% or less.

By cooling the roasting after completion of roasting to 35 to 50 ° C., not to room temperature of about 20 ° C., the cooling time can be greatly shortened and the quality and productivity can be improved. It's convenient and convenient. This is based on the finding that, when the temperature of the roasted beans reaches 35 to 50 ° C., the scent does not substantially dissipate even after rapid cooling including cold air. Further, by handling the beans before and after roasting in a dry atmosphere, the moisture content of the roasted beans is kept in a low range of 3.0% or less, so that it is easy to obtain high-quality roasted beans with a high scent. However, the water content of roasted beans is 1.5 in actual production.
It is only necessary to be in the range of 3.0%. Further, by setting the cooling rate by the suction fan to 1.0 to 2.0 ° C./sec, the cooling rate is not too slow, and therefore productivity is not lowered, and there is a possibility that moisture is absorbed during cooling. Can be minimized.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below. First, as the coffee beans to be roasted, coffee beans made of Arabica seeds are selected and used. In general, coffee beans of Robusta species are often mixed and used in addition to Arabica species, but only arabica species having good aroma characteristics are used without roasting the excellent aroma components of arabica species. Roast. The roasting temperature may be about 210 to 240 ° C., which is usually performed, and the roasted coffee beans are taken out when the roasting degree reaches an appropriate roasting degree for a predetermined time, and the roasted coffee beans are shielded from a high humidity atmosphere, Use the suction fan quickly to cool. In this case, it is necessary not to use any water for cooling after roasting, and do not sprinkle the roasted beans after roasting or put the roasted beans into the cooling water as is conventionally done. . Further, when the suction fan is operated, it is preferable to sufficiently stir or fluidize the roasted coffee beans. The capacity or capacity of the suction fan can be changed according to the amount of roasted beans.

The roasted beans may be cooled to 35 to 50 ° C. This is because at such a low temperature, there is no particular problem even if it proceeds to the subsequent steps. In short, the cooling rate after roasting is at least 2.5 ° C / sec or less, preferably 1.0 to
It may be set to 2.0 ° C./second.

[0013]

EXAMPLES Next, examples of the present invention will be described in detail.

(Examples 1 to 3) As raw beans, 3 kinds of Arabica (variety name: Guatemala SHB, Colombia SUP,
Santos No. 2/18) 100g each is weighed and used as a roasting machine Probat Corporation sample roaster (type: Br)
3P100) was used and heated to 200 to 230 ° C. (final ultimate temperature: 230 ° C.) and roasted. When the specified roasting color is reached, the roasted beans are discharged from the roasting chamber, and in a dry atmosphere in which the moisture content is kept low for 100 seconds, only suction cooling with a suction fan is performed to cool to 40 ° C (40 ° C). Cooling rate up to: 1.90 ° C / sec).

After completion of roasting, the roasted beans are crushed to obtain coffee powder 2
The aroma content of g was analyzed by gas chromatography. The measurement by gas chromatography was carried out for each aroma amount of low boiling point, medium boiling point, and high boiling point, but it was evaluated by the total aroma amount (total peak area on the obtained measurement chart). 30 g of the crushed powder was extracted with 450 g of hot water at 90 ° C. (paper filter method), and a sensory test was performed to evaluate.

(Comparative Examples 1 to 3) After roasting green coffee beans similar to those in Examples 1 to 3, 10 g of cooling water (quenching water) was sprayed, and then discharged from the roasting chamber and similarly 4
Cooled to 0 ° C. In this case, the time required to cool to 40 ° C. was 70 seconds (cooling rate up to 40 ° C .: 2.71 ° C./second). The evaluation method was the same as in Examples 1 to 3.

Table 1 shows the evaluation results of Examples 1 to 3 and Comparative Examples 1 to 3. In addition, similar tests were carried out for only Robusta species and for blended products containing Arabica and Robusta species. The results are also shown in Table 1.

In addition, in Examples 1 to 3 and Comparative Examples 1 to 3, in order to eliminate the influence of roasted color on the sensory evaluation, heating and holding were performed so that roasted colors of the same raw bean species were almost the same. I set the time.

(Comparative Example 4) As raw beans, 100 g of Robusta species (variety name: Indonesia AP-1) was weighed, and sample roaster (Type: Br3P1) manufactured by Probat Corporation.
00) was used and roasted in the same manner as in Example 1.

When the specified roasting color is reached, the roasted beans are discharged from the roasting chamber, suction-cooled for 90 seconds and cooled to 40 ° C. to obtain a sample (cooling rate up to 40 ° C. : 2.
11 ° C / sec).

(Comparative Example 5) The same green beans as in Comparative Example 4 were used for roasting in the same manner, but 10 g of cooling water was sprayed, then discharged from the roasting chamber and cooled to 40 ° C. In this case, the time required to cool to 40 ° C was 60 seconds (40 ° C
Cooling rate up to: 3.17 ° C./sec).

(Comparative Example 6) As a blended product containing Arabica and Robusta, Arabica (Columbia SU
P; 20 g, Santos No2; 30 g) 50 g, Robusta species (Indonesia AP-1) 50 g, 100 g in total, were weighed, and Probat Corporation sample roaster (Type:
Br3P100) was used and roasted under the same conditions as in Example 1.

When the specified roasting color is reached, the roasted beans are discharged from the roasting chamber, suction-cooled for 85 seconds and cooled to 40 ° C. to obtain a sample (cooling rate up to 40 ° C. : 2.
24 ° C / sec).

(Comparative Example 7) Roasting was performed in the same manner using the same green beans as in Comparative Example 6, but 10 g of cooling water was sprayed, then discharged from the roasting chamber and cooled to 40 ° C. In this case, the time required to cool to 40 ° C was 65 seconds (40 ° C
Cooling rate up to: 2.92 ° C./sec). Table 1 also shows the evaluation results of Comparative Examples 4 to 7.

[0025]

[Table 1] As shown in Table 1, when evaluated with the same raw beans,
All of the ones cooled with a suction fan at a cooling rate of 2 ° C / sec had a better scent than those cooled with cooling water, and the sensory evaluation of the scent in the extract was also good. The excellent characteristics of high-grade Arabica varieties can be directly reflected in coffee beverages.

Comparative Example 4 using only Robusta species has a strong scent, but it cannot be said to be a high-quality scent.
It is clear that the results of Nos. 1 to 3 are inferior, and that the blended product containing Arabica and Robusta is also inferior to Examples 1 to 3 in which a good scent is obtained.

Claims (2)

[Claims] 1. Coffee beans made of Arabica seeds are heated to a roasting temperature for a predetermined time and then cooled at a cooling rate of at least 2.5 ° C./second or less by a suction fan in a dry atmosphere without using cooling water. How to roast coffee beans. 2. The cooling to 1.0 to 50 to 35 to 50 ° C.
The method for roasting coffee beans according to claim 1, wherein the roasted coffee beans are cooled at a cooling rate of 2.0 ° C./sec and the water content of the roasted coffee beans after cooling is set to 3.0% or less.