阅读说明：本技术 一种咖啡提取物的制备方法及其提取装置 (Preparation method and extraction device of coffee extract ) 是由 孟宪乐 徐炜 施君超 于 2019-10-10 设计创作，主要内容包括：本发明提供一种咖啡提取物的制备方法及其提取装置,在较高温度下用酒精蒸汽和氮气带出咖啡在烘焙过程中产生的香气,同时在高温下酒精与咖啡中一些酸类物质发生反应形成酯类物质,使提取的咖啡香气更为柔和、丰富和圆润,本发明的提取装置为：惰性气体储气罐通过进气管与萃取柱的一端连接,在惰性气体储气罐和萃取柱之间的进气管上设有萃取助剂蒸汽发生器,萃取柱的另一端通过出气管与冷凝器相连,冷凝器下方连接香气收集罐,冷凝器通过输气管与输气泵及进气管相连。本发明的方法所得的咖啡提取物香气还原度高；提取后的咖啡渣还可用酒精回流提取咖啡中呈味物质。提取装置设计合理、应用方便灵活,能高效提取咖啡的香气物质,香气还原度高。(The invention provides a preparation method of coffee extract and an extraction device thereof, which carry the aroma generated in the roasting process of coffee by using alcohol steam and nitrogen at a higher temperature, and simultaneously, alcohol reacts with some acid substances in the coffee at a high temperature to form ester substances, so that the aroma of the extracted coffee is softer, richer and more mellow, and the extraction device of the invention is as follows: the inert gas storage tank is connected with one end of the extraction column through an air inlet pipe, an extraction auxiliary agent steam generator is arranged on the air inlet pipe between the inert gas storage tank and the extraction column, the other end of the extraction column is connected with a condenser through an air outlet pipe, a fragrance collection tank is connected below the condenser, and the condenser is connected with an air delivery pump and an air inlet pipe through an air delivery pipe. The coffee extract obtained by the method has high aroma reduction degree; the coffee grounds after extraction can also be used for extracting flavor-developing substances in the coffee by alcohol reflux. The extraction device has reasonable design, convenient and flexible application, can efficiently extract the aroma substances of the coffee, and has high aroma reduction degree.)

1. A method for preparing coffee extract comprises the following steps:

A. filling roasted coffee powder into an extraction column, putting alcohol into an extraction auxiliary steam generator, introducing nitrogen to replace air in the extraction column, and opening a rear-section condenser at the temperature of-20 to-70 ℃;

B. heating the extraction column to 100-280 ℃, starting to heat the coffee powder, continuously introducing nitrogen, simultaneously introducing alcohol vapor, and collecting the cooled liquid, namely the coffee extract A;

C. and (3) refluxing and extracting the extracted coffee grounds by using alcohol, and then filtering and concentrating to obtain the coffee extract B.

2. A process for the preparation of a coffee extract as claimed in claim 1, wherein the amount of coffee used per batch is between 100g and 100kg, the nitrogen flow rate is between 5 and 5000ml/min and the alcohol evaporation rate is between 1 and 1000 ml/min.

3. The method of preparing coffee extract according to claim 1, wherein the extraction time of the coffee extract A is varied according to the flow rate of the nitrogen gas and the alcohol and the heating temperature of the extraction column, and the extraction time is 10-30 min.

4. The method of preparing coffee extract as set forth in claim 1, wherein the coffee powder used has a particle size of 0.25mm to 2mm and is roasted from light to medium degrees and is selected from the group consisting of arabica beans and robusta beans.

5. The method of preparing a coffee extract as claimed in claim 1, wherein the weight of the extraction solvent of the coffee extract B is 3-5 times the weight of the coffee grounds.

6. An extraction device of coffee extract, comprising: extraction post, inert gas storage tank, extraction auxiliary agent steam generator, condenser, fragrance collection tank, buffer tank, gas transmission pump and gas-supply pipe, its characterized in that inert gas holder (2) are connected with the one end of extraction post (1) through intake pipe (4), and the other end of extraction post (1) passes through outlet duct (6) and links to each other with condenser (7), is connected with buffer tank (5) on outlet duct (6) between extraction post (1) and condenser (7), and fragrance collection tank (8) is connected to condenser (7) below, and condenser (7) link to each other with gas transmission pump (10) entry through gas-supply pipe A (9), and gas transmission pump (10) export links to each other with intake pipe (4) through gas-supply pipe B (11).

7. The extraction apparatus of coffee extract as claimed in claim 6, characterized in that an extraction aid steam generator (3) is provided in the gas inlet pipe (4) between the inert gas holder (2) and the extraction column (1).

8. The extraction apparatus of coffee extract according to claim 6, wherein the outlet of the gas delivery pump (10) is disposed between the inert gas storage tank (2) and the extraction aid steam generator (3) through a gas delivery pipe B (11), and a three-way valve (12) is disposed on the gas delivery pipe B (11).

9. The extraction apparatus of coffee extract as claimed in claim 6, wherein; the extraction column (1) is a closed extraction device rotating around the axis of the extraction column, the extraction column (1) is made of glass or stainless steel, and the diameter of the extraction column is 3-50 cm.

Technical Field

The invention relates to a preparation method of a natural spice extract and extraction equipment thereof, in particular to a preparation method of a coffee extract and an extraction device thereof.

Background

Coffee is an evergreen shrub or small arbor plant of the family rubiaceae. The yield, sales and consumption of the plant are the top of three major beverage plants (coffee, tea and cocoa) in the world. Coffee is produced in more than 70 countries and regions of the tropical and subtropical regions. Coffee production is mainly concentrated in tropical developing countries in latin america, africa, asia, etc., such as brazil, columbia, indian lixia, russia, vietnam, etc. Coffee beans are dark green or dark brown, have unique and mellow fragrance, slightly bitter and astringent taste, and have health-care effects of losing weight, refreshing, inducing resuscitation, promoting urination, resisting oxidation and the like due to a large amount of active ingredients, so that the coffee beans are popular with more and more consumers. Meanwhile, the coffee contains rich volatile aroma components, so that the coffee is widely applied to the flavor and fragrance industry.

The roasting of coffee is to heat raw beans to promote a series of physical and chemical reactions inside and outside the coffee beans, and in the process, the bitter, sweet, sour and other tastes of the coffee are generated to form alcohol degree and color tone. Roasted green beans lose part of their moisture and turn yellow. During this process, the coffee beans expand, transitioning from a firm, high-density green bean state to a low-density fluffy state. The baking temperature, the baking mode and the baking time are the main factors for determining the final flavor.

The roasting mode of professional coffee is generally divided into the following eight stages.

1. Very shallow baking (light toast): the degree of baking; baking is done very lightly, also known as light baking. Generally used for inspection, and rarely used for tasting.

2. Light baking (cinmamorost): the degree of baking; light baked, also known as cinnamon. A degree of roasting commonly employed for american coffee.

3. Mini baking (mediumburn): the degree of baking; medium baking, also known as micro medium baking. It is often used for roasting of mixed coffee.

4. Medium bake (highcoast): the degree of baking; medium and light deep baking, also known as concentration baking. Is most popular with Japanese and European people. (blue mountain coffee)

5. Medium deep baking (CITYRoast): the degree of baking; medium deep baking, also known as urban baking. The most standard roast degree is often used in french coffee. (Brazil, Columbia)

6. Deep baking (FULL-citroroast): the degree of baking; micro deep baking, also known as deep urban baking. Belongs to the baking method of the Chinese south American style, and is extremely suitable for preparing various ice coffees.

7. Very deep baking (french roast): the degree of baking; deep baking, also known as french baking. Is very suitable for coffee Europe, Vienna coffee.

8. Very deep baking (ItalianRoast): the degree of baking; extremely deep baking, also known as Italian baking. Is suitable for quick coffee and cappuccino. Most are used on the Espresso series of coffees.

The traditional extraction method of natural perfume mainly comprises the following steps: steam distillation, solvent extraction, pressing, and adsorption. Patent CN99804856.9 discloses a process for stripping a slurry of ground coffee, from which aroma components are stripped, the coffee aroma being present in the form of an aqueous solution, which is suitable for the production of coffee concentrates or instant coffee, but is not highly suitable in the aroma industry; supercritical carbon dioxide extraction has also been widely applied to the extraction of natural products in recent years, for example, patent CN201810704609.5 discloses a method for extracting natural coffee aroma from coffee beans by supercritical carbon dioxide extraction, which is limited to high equipment investment and high operation cost, and is not favorable for industrial production, but the natural coffee aroma obtained by the method has pure aroma, and has positive significance for coffee aroma analysis and coffee essence preparation.

Patent CN201711391473.9 discloses a method for extracting coffee extract from coffee grounds, which comprises the steps of carrying out dry distillation on coffee grounds at 350-420 ℃ under anaerobic condition to obtain coffee grounds fraction, carrying out reduced pressure rectification on the fraction at 45-65 ℃ and-0.03-0.05 MPa to obtain supernatant, and purifying the supernatant oil phase to obtain the coffee extract.

The invention provides a preparation method of a coffee extract, and aims to provide a brand-new coffee extraction method. The aroma of coffee is easily lost, and researches show that the interaction between the melanoidin in the coffee and the volatile components in the coffee is a main factor causing the loss of the aroma of the coffee, and under the heating condition, the coffee aroma components, particularly trace sulfur-containing flavor substances such as 2-furanthiol, are accelerated to react with the melanoidin, and the aroma of the coffee is almost completely lost after half an hour in hot water in general. The traditional extraction method of the coffee extract generally adopts hot reflux extraction by hot water and alcohol, then concentration, the loss of coffee aroma is large in the extraction process, the coffee characteristics of the extract are distorted or changed, and the newer technology uses supercritical extraction, but the supercritical extraction equipment has large investment, high production cost, high product price and complex process, and can extract a large amount of pectin and other substances, and the application range in essence is limited.

The invention provides a process for producing aroma in the baking process and then extracting the aroma by using alcohol steam, which solves the defects of incomplete coffee aroma and poor reduction degree. And simultaneously, the problems of high equipment investment cost and unfavorable industrial production are solved.

The preparation method of the coffee extract comprises the following steps:

A. filling roasted coffee powder into an extraction column, putting alcohol into an extraction auxiliary steam generator, introducing nitrogen to replace air in the extraction column, and opening a rear-section condenser at the temperature of-20 to-70 ℃;

B. heating the extraction column to 100-280 ℃, starting to heat the coffee powder, continuously introducing nitrogen, simultaneously introducing alcohol vapor, and collecting the cooled liquid, namely the coffee extract A;

C. and (3) refluxing and extracting the extracted coffee grounds by using alcohol, and then filtering and concentrating to obtain the coffee extract B.

The diameter of the extraction column is 3-50cm, the dosage of each batch of coffee is 100 g-100 kg, the nitrogen flow rate is 5-5000ml/min, and the alcohol evaporation rate is 1-1000ml/min

The heating temperature of the extraction column is 100-280 ℃, and the preferred heating temperature is 180-210 ℃.

The temperature of the condenser is-20 to-70 ℃, and the preferable temperature is-30 to-40 ℃.

The extraction time of the coffee extract A is different according to the flow of the introduced nitrogen and the introduced alcohol and the heating temperature of the extraction column, the extraction time is 10-30min, and the preferable extraction time is 15-25 min.

The coffee powder used has a particle size of 0.25mm to 2mm, preferably a particle size of 0.5mm to 1 mm.

The coffee powder is baked from light to medium degree and is selected from Arabica bean and Apocynum venetum bean.

The weight of the extraction solvent of the coffee extract B is 2-6 times of the weight of the coffee grounds, preferably 3-5 times of the weight of the coffee grounds.

The invention also provides an extraction device of the coffee extract. The method comprises the following steps: extraction post, inert gas storage tank, extraction auxiliary agent steam generator, condenser, fragrance collection tank, buffer tank, gas transmission pump and gas-supply pipe, its characterized in that inert gas holder 2 is connected with the one end of extraction post 1 through intake pipe 4, and the other end of extraction post 1 passes through outlet duct 6 and links to each other with condenser 7, is connected with buffer tank 5 on outlet duct 6 between extraction post 1 and condenser 7, and fragrance collection tank 8 is connected to condenser 7 below, and condenser 7 passes through gas-supply pipe A9 and links to each other with gas transmission pump 10 entry, and gas transmission pump 10 export links to each other with intake pipe 4 through gas-supply pipe B11.

An extraction auxiliary agent steam generator 3 is arranged on an air inlet pipe 4 between the inert gas storage tank 2 and the extraction column 1.

The outlet of the gas transmission pump 10 is arranged between the inert gas storage tank 2 and the extraction auxiliary agent steam generator 3 through a gas transmission pipe B11. The three-way valve 12 is arranged on the gas conveying pipe B11.

The extraction column 1 used in the invention is a closed extraction device rotating around the axis of the extraction column, the extraction column 1 is made of glass or stainless steel, and the diameter of the extraction column is 3-50 cm. .

The inert gas used in the inert gas storage tank 2 is nitrogen. The extraction aid used in the extraction aid steam generator 3 is one of ethanol, ethyl acetate, cyclohexane, and methylene chloride.

The coffee extract has the advantages that the aroma generated in the roasting process is brought out by alcohol steam at a higher temperature, the loss of aroma caused by the absorption of melanoidin substances to aroma components is avoided, the alcohol can react with some acid substances in the coffee at a high temperature to form chemical substances such as ester and the like, so that the extracted coffee aroma is softer and more mellow, the coffee extract obtained by the coffee extract has high reduction degree on the coffee aroma, and the high-concentration coffee extract can be obtained without concentration; the extracted coffee grounds can also be used for extracting flavor development substances in the coffee by alcohol reflux, and the two extracts can be used independently or in combination, so that the coffee grounds can be more flexibly and conveniently applied to essences.

One end of an extraction column of the extraction device is connected with an inert gas storage tank, inert gas is introduced during extraction, under the protection of the inert gas, aroma substances emitted by natural spices heated in the extraction column are taken out and conveyed into a condenser through an air outlet pipe, and the aroma components are condensed by the low temperature of the condenser and then collected to obtain the natural spice aroma extract. Because the extraction column is rotatable, can accurately control the temperature and heat and is closed, different extraction temperatures can be set according to the properties of strong volatility, weak boiling point, high and low boiling point and the like of the aroma components of different natural spices; the extraction column can rotate to ensure that the spice is heated uniformly in the extraction column. The whole extraction device is filled with nitrogen in the extraction process, so that the influence of oxygen and heating on the aroma components is reduced as much as possible, and the nitrogen also serves as a medium for conveying the aroma components; the device is provided with a gas transmission pump, and the nitrogen treated by the condenser is sent back to the extraction system for recycling. The extraction device is provided with an extraction auxiliary steam generator, and an appropriate extraction auxiliary can be selected according to the polarity of the aroma component of the natural spice under the condition of need so as to improve the extraction efficiency. The extraction device provided by the invention has the advantages of simple and reasonable structure, simplicity and convenience in use and high flexibility of use scenes.

Drawings

FIG. 1 is a schematic structural view of the present invention;

in the figure: 1 extraction column, 2 inert gas holders, 3 extraction auxiliary agent steam generators, 4 air inlet pipes, 5 buffer tanks, 6 air outlet pipes, 7 condensers, 8 fragrance collection tanks, 9 air delivery pipes A, 10 air delivery pumps, 11 air delivery pipes B and 12 three-way valves.

Detailed Description

The invention will be further elucidated with reference to the following specific examples. The specific embodiments described herein are merely illustrative of the invention and do not delimit the invention.

Example one

Referring to fig. 1, the extraction device of the present embodiment includes: the device comprises an extraction column 1, an inert gas storage tank 2, an extraction auxiliary agent steam generator 3, an air inlet pipe 4, a buffer tank 5, an air outlet pipe 6, a condenser 7, a fragrance collection tank 8, an air delivery pipe A9, an air delivery pump 10, an air delivery pipe B11 and a three-way valve 12.

The extraction column 1 of this example was made of glass, and a 3cm diameter glass column was used, and heated with a heating belt, and alcohol was vaporized and heated with a three-necked flask, and the alcohol rate was controlled by controlling the dropping rate. The extraction column 1 is a closed extraction device rotating around the axis of the extraction column, and the temperature control range of the extraction column 1 is from room temperature to 400 ℃. This example is 180 ℃.

One end of the extraction column 1 is connected with an inert gas storage tank 2 through a gas inlet pipe 4. The inert gas contained in the inert gas storage tank 2 is nitrogen. An extraction auxiliary agent steam generator 3 is arranged on an air inlet pipe 4 between the inert gas storage tank 2 and the extraction column 1. The extraction aid used in the extraction aid steam generator 3 is one of ethanol, ethyl acetate, cyclohexane, and dichloromethane, and in this embodiment, ethanol. And (3) starting an inert gas storage tank 2 to enable inert gas to pass through the extraction column 1 and the whole device, wherein the other end of the extraction column 1 is connected with a condenser 7 through an air outlet pipe 6, and the temperature control range of the condenser 7 is from room temperature to-70 ℃, and is-40 ℃ in the embodiment. A buffer tank 5 is connected on an air outlet pipe 6 between the extraction column 1 and the condenser 7, and the buffer tank 5 can collect solid dust brought out from the extraction tank and prevent the dust from entering the condenser to block the condenser. The lower part of the condenser 7 is connected with a fragrance collecting tank 8, and the condenser 7 is connected with an inlet of an air delivery pump 10 through an air delivery pipe A9; the three-way valve 12 is arranged on the gas transmission pipe B11; the outlet of the gas transmission pump 10 is connected with the gas inlet pipe 4 through a gas transmission pipe B11 and is arranged between the inert gas storage tank 2 and the extraction auxiliary agent steam generator 3.

Adding 100g of lightly roasted coffee powder into an extraction column 1, fixing two ends of the extraction column 1 by using glass wool, introducing 10ml/min of nitrogen, putting alcohol into an extraction aid steam generator, setting the evaporation speed of the alcohol to be 2ml/min, heating the extraction column to 280 ℃ for heating the coffee powder, heating the coffee powder to 180 ℃, continuously introducing the nitrogen, simultaneously introducing the alcohol steam, opening a rear-section condenser, setting the temperature of the condenser to be-40 ℃, extracting for 20 minutes, and collecting 42ml of condensate which is coffee extracting solution A; extracting coffee residue with 4 times of alcohol under reflux for 2 hr, filtering, concentrating the filtrate to 1/4 weight of coffee residue to obtain coffee extract B, and mixing coffee extract A and coffee extract B at a certain ratio for essence production.

Example two

The same as in example one, except that the extraction column 1 was a 5cm diameter glass column, heated with a heating belt, alcohol was vaporized by heating with a three-necked flask, and the alcohol rate was controlled by controlling the dropping rate. Adding 500g of lightly baked coffee powder into an extraction column, fixing two ends with glass wool, introducing 50ml/min of nitrogen, setting the evaporation speed of alcohol to be 10ml/min, heating the coffee powder to 210 ℃, and extracting for 15 minutes. 156ml of condensate was collected as coffee extract A.

EXAMPLE III

The same as in example one, except that the extraction column 1 was heated with a heating belt using a 15cm diameter stainless steel column, and alcohol was vaporized using a tube still vaporizer by measuring the alcohol rate by a metering pump. Adding 15kg of moderately roasted coffee powder into an extraction column, fixing two ends with glass wool, introducing 800ml/min of nitrogen, setting the alcohol evaporation speed at 50ml/min, heating the coffee powder to 210 ℃, and extracting for 30 minutes. 1600ml of condensate was collected as coffee extract A.