CA1086556A - Process of obtaining coffee oil from roasted coffee - Google Patents
Process of obtaining coffee oil from roasted coffeeInfo
- Publication number
- CA1086556A CA1086556A CA267,753A CA267753A CA1086556A CA 1086556 A CA1086556 A CA 1086556A CA 267753 A CA267753 A CA 267753A CA 1086556 A CA1086556 A CA 1086556A
- Authority
- CA
- Canada
- Prior art keywords
- coffee
- oil
- aroma
- roasted
- expressed
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- A—HUMAN NECESSITIES
- A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
- A23F—COFFEE; TEA; THEIR SUBSTITUTES; MANUFACTURE, PREPARATION, OR INFUSION THEREOF
- A23F5/00—Coffee; Coffee substitutes; Preparations thereof
- A23F5/46—Coffee flavour; Coffee oil; Flavouring of coffee or coffee extract
- A23F5/48—Isolation or recuperation of coffee flavour or coffee oil
Landscapes
- Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Food Science & Technology (AREA)
- Polymers & Plastics (AREA)
- Tea And Coffee (AREA)
Abstract
ABSTRACT
A process of obtaining coffee oil having aroma prin-ciples useful in the aromatization of foodstuffs is described.
The process involves expressing coffee oil from roasted coffee by subjecting roasted coffee to a pressure of from 5,000 to 20,000 psi (350 to 1400 kg/cm2) while passing an inert gas through, and maintaining an environment of said inert gas over, the roaster coffee and the oil expressed therefrom.
By controlling the flow rate of the inert gas within critical limits, the aroma principles may be balanced and the aroma quality and intensity may be improved.
A process of obtaining coffee oil having aroma prin-ciples useful in the aromatization of foodstuffs is described.
The process involves expressing coffee oil from roasted coffee by subjecting roasted coffee to a pressure of from 5,000 to 20,000 psi (350 to 1400 kg/cm2) while passing an inert gas through, and maintaining an environment of said inert gas over, the roaster coffee and the oil expressed therefrom.
By controlling the flow rate of the inert gas within critical limits, the aroma principles may be balanced and the aroma quality and intensity may be improved.
Description
This invention relates to the production of coffee aroma principles useful in the aromatization of food products generally and soluble or instant coffee in particular. More particularly, this invention is concerned with a process of obtaining coffee oil having balanced aroma principles and con-trolled aroma quality and intensity from roasted coffee.
Many soluble or instant coffee powders are found to be deficient in the aromas contained within fresh roasted and ground coffee. In the case of soluble coffee powder, i.e., the dried water extract of roasted coffee, a considerable amount of the aromas may be lost in the process of dehydrating the extract to the dry powder state. Generally, it is difficult to retain or capture all of the aroma principles in a coffee extract due to the volatilization and degradation of these aroma principles in drying. Attempts have been made, however, to incorporate -~
coffee aroma principles into and onto a dried coffee extract. -~
These aromatization techniques have included a wide variety of methods and have encompassed the utilization of aroma prin-ciples derived from coffee by such methods as using the aromas contained within grinder gas or roaster gas as well as the aromas obtained by dry distilling or solvent extracting roasted -~
coffee. In addition, aroma principles useful in the aroma-tization of soluble or instant coffee have been obtained from roasted coffee by expressing the coffee oil contained therein.
Generally this method involves separation of the oil from roasted coffee by dividing the coffee into smaller particles and compressing these particlesg typically by the use of expressing means. The expressed coffee oil contains quantities of low, medium and high boiling aromatics such that when the oil is plated on soluble coffee powder, it enhances the dried extract with the desired characteristic coFfee aromas. -However, any substantial amount or intensity of aromas supplied _ 1 _ - , , , ;S5~
to the soluble coffee powder in this manner usually requires a large quantity of expressed coffee oil to be supplied. This may frequently cause the powder to have an unattractive wet appearance and to be less free-flowing than a powder which is not plated with the oil. Such a drawback is able to be overcome by concen-trating or folding the aroma principles in a given quantity ~ ;~
of expressed oil and thereafter applying the oil containing a larger amount of aroma principles to the soluble coffee powder. Notwithstanding this advance, which is generally de-scribed in Canadian Patent No. 603,954, the problem still remains of maintaining or attempting to achieve a balance of the aroma principles within coffee oil which has been expressed from roasted coffee. Thus, in the subsequent treatment and handling -of the coffee oil as well as the dried soluble coffee powder to which the coffee oil may be applied, and also during the handling, packaging and storage of the final product, certain of the aroma principles may be lost because of their fugitive nature.
It has now been discovered that a coffee oil having balanced aroma principles and controlled aroma quality and intensity may be obtained from roasted coffee by expressing coffee oil from roasted coffee by subjecting the roasted coffee -~
to a pressure of from 5,000 to 20,000 psi (350 kg/cm2 to 1400 kg/cm2) while passing an inert gas through, and maintaining an environment of said inert gas over, the roasted coffee and -the oil expressed therefrom. The roasted coffee is subjected to the oil expressing operation in a pressing means, typically any one of a large number of oil presses that are commercially available, while maintaining the temperature of the coffee during expressing at below about 175C and the temperature of the oil being expressed at between 25 and 50C. Preferably, the inert gas is carbon dioxide although other inert gases such as nitrogen may be employed either alone or in ~ . , ~ 5 ~ ~
combination with the carbon dioxide. A critical feature of the process is that the flow rate at which the ;nert gas is passed over the roasted coffee and the oil expressed therefrom should be maintained at between about 0.1 and 2.0 cfm (between about 47 and 944 cm3/sec.) within and surrounding the pressing means.
To sorne extent, the flow rate may be varied within the afore-mentioned limits, but care must be taken to ensure that the flow rate is maintained within such limits since the aroma principles are sought to be obtained in a balanced manner, i.e., controlled amounts of the low, medium and high boiling aromatics are desired. By regulating the flow rate of the inert gas within the pressing means, it is now possible to ~-control the quality and intensity of the aromas within the coffee oil that is expressed from the roasted coffee. Moreover, because of the balanced aromatics within the cofFee oil produced by the process of this invention, the coffee oil as well as the aroma principles contained therein are less costly to produce.
Thus, it is apparent that savings may be realized both in labor and energy as well as in raw materials, that is, the roasted coffee from which the coffee oil is expressed.
It should be mentioned that while inert gases have ~
previously been employed in the production of coffee oil having ~ -aroma principles therein, the use of such gases has been essentially for the purposes of serving as either a purging blanket or a transfer force. Thus, coffee oil has been obtained from roasted coffee by expelling the oil from the roasted coffee ~;
in an inert gas atmosphere so that the degradation of the coffee aromas by oxygen is prevented. Also, inert gases have -~
been employed to purge the headspace of vessels used to store coffee oil. As mentioned, inert gases have been further utilized as a transfer force so as to transport oil from the various , ~ o~i5~6, vessels and apparatuses utilized in coffee oil production and subsequent utilization of the coffee oil in the plating of soluble or instant coffee. Notwithstanding such conventional uses of inert gases in the production of coffee oil, the present discovery is predicated on the unexpected finding that by maintaining an inert gas atmosphere over the roasted coffee and the oil expressed therefrom and also passing such inert gas at a specified flow rate over the roasted coffee and the oil expressed therefrom, the aromatics within the coffee oil are able to be balanced much more carefully with the result that the coffee oil obtained has its aroma quality and intensity critically controlled. It is theorized that the process of the present invention results in a partial fractionation of the aroma principles of the coffee oil. It may also be noted that while maintaining and passing the inert gas over the ~ ~ -roasted coffee and the oil expressed therefrom lead to the -;
production of a coffee oil having balanced aromatic principles, -departure from the limits of flow rate results in unbalancing the aroma principles within the expressed coffee oil. Thus, if ;`
an insufficient flow rate of the inert gas is not ensured, then the deleterious effect of oxygen on the coffee oil and also ~;
an unbalancing of the aromatic principles therein may be noted.
Also, if the flow rate is permitted to exceed the limits which have been critically established, it appears that all of the aromatics may be effectively stripped from the expressed or expelled oil. In either case, then the aroma principles become unbalanced which is undesired.
In operating the pressing means so as to express`the coffee oil from the roasted coffee, as mentioned previously, any of a variety of commercially available presses or oil expellers may be utilized. The roasted coffee from which the oil is to be expressed or expelled is passed in the form of particles into the pressing means. During the expressing - 4 ~
~i536S~;6 operation, a pressure is developed on the expelled cake or meal. Subsequently, the expelled cake or meal may be extruded and cut into pellets for reintroduction into percolators with normal roasted and ground coffee from which the soluble or instant coffee is being produced and which may be later plated with the oil expressed from the roasted coffee by the process of this invention. During operation of the pressing means, it is desirable to cool the roasted coffee from which the coffee oil is being expelled so that the aromatic principles do not become degraded by exposure to inordinately high tempe-ratures which may be developed during the expressing operation.
The expressed coffee oil is discharged from the pressing means and its temperature upon discharge in the range of from about 25 to 50 C. The expressed coffee oil may be then immediately cooled and clarified as, for example, by centrifuging. The coffee oil, having balanced aroma principles as obtained by the process of the present invention, may be plated onto soluble or instant coffee in amounts of from about 0.1 to about 1%, by weight, based on the soluble or instant coffee powder. As mentioned previously, however, the coffee oil may have its aroma principles enhanced or increased by recovering the aroma principles from a given quantity of coffee oil and subsequently incorporating the concentrated aroma principles in another quantity of coffee oil, thereby increasing the overall concentration of aroma principles in the latter quantity bf coffee oil. The inert gas, particularly carbon dioxide, may be introduced into the pressing means by any ;~
suitable device such as gas nozzles.
In order that the present invention may be more fully understood, but without in any way attempting to limit it thereto, the following illustrative example is furnished.
, , - . . . .
.' : .
:. , . ' ~ .
~3~i5~
EXAMPLE
An Anderson* expe11er was charged with roasted whole coffee beans and the feed rate of the roasted coffee to the expeller was maintained at 300 pounds per hour. During the operation of the expeller, the temperature of the roasted coffee within the expeller was controlled to 160 C., the temperature of the coffee oil expressed was noted to be 30 C. During operation of the expeller9 carbon dioxide gas was admitted into and shrouded the expeller at a flow rate of 0.3 cfm (142 cm3/
sec.). The run was allowed to continue for 16 hours and the coffee oil expressed from the roasted coffee was recovered and analysed by gas chromatographic methods at hourly intervals following the start-up of the expeller. A similar run was made - ~ -on the same equipment utilizing the same type of roasted coffee, `- !~
feed rates and other conditions except that the flow rate of carbon dioxide gas was 2.5 cfm, the coffee oil was similarly recovered and analysed. A third run was made on the same equipment utilizing the same type of roasted coffee, feed rates and other conditions except that there was no admission of, or blanketing with, carbon dioxide, the coffee oil was similarly `~
recovered and analyzed. From the gas chromatographic data, it was found that the coffee oil expressed by the process of the present invention from roasted coffee produced a more balanced aroma blend and more desirable aroma principles than the coffee `~-oil obtained in either of the other runs. This finding was further confirmed when the coffee oil from each of the runs was subsequently plated onto soluble coffee powder and the oil-plated -~
soluble coffee powders were evaluated by an expert aroma panel.
'~
* Manufacturer's name ~ -,,,~ , , - ,,
Many soluble or instant coffee powders are found to be deficient in the aromas contained within fresh roasted and ground coffee. In the case of soluble coffee powder, i.e., the dried water extract of roasted coffee, a considerable amount of the aromas may be lost in the process of dehydrating the extract to the dry powder state. Generally, it is difficult to retain or capture all of the aroma principles in a coffee extract due to the volatilization and degradation of these aroma principles in drying. Attempts have been made, however, to incorporate -~
coffee aroma principles into and onto a dried coffee extract. -~
These aromatization techniques have included a wide variety of methods and have encompassed the utilization of aroma prin-ciples derived from coffee by such methods as using the aromas contained within grinder gas or roaster gas as well as the aromas obtained by dry distilling or solvent extracting roasted -~
coffee. In addition, aroma principles useful in the aroma-tization of soluble or instant coffee have been obtained from roasted coffee by expressing the coffee oil contained therein.
Generally this method involves separation of the oil from roasted coffee by dividing the coffee into smaller particles and compressing these particlesg typically by the use of expressing means. The expressed coffee oil contains quantities of low, medium and high boiling aromatics such that when the oil is plated on soluble coffee powder, it enhances the dried extract with the desired characteristic coFfee aromas. -However, any substantial amount or intensity of aromas supplied _ 1 _ - , , , ;S5~
to the soluble coffee powder in this manner usually requires a large quantity of expressed coffee oil to be supplied. This may frequently cause the powder to have an unattractive wet appearance and to be less free-flowing than a powder which is not plated with the oil. Such a drawback is able to be overcome by concen-trating or folding the aroma principles in a given quantity ~ ;~
of expressed oil and thereafter applying the oil containing a larger amount of aroma principles to the soluble coffee powder. Notwithstanding this advance, which is generally de-scribed in Canadian Patent No. 603,954, the problem still remains of maintaining or attempting to achieve a balance of the aroma principles within coffee oil which has been expressed from roasted coffee. Thus, in the subsequent treatment and handling -of the coffee oil as well as the dried soluble coffee powder to which the coffee oil may be applied, and also during the handling, packaging and storage of the final product, certain of the aroma principles may be lost because of their fugitive nature.
It has now been discovered that a coffee oil having balanced aroma principles and controlled aroma quality and intensity may be obtained from roasted coffee by expressing coffee oil from roasted coffee by subjecting the roasted coffee -~
to a pressure of from 5,000 to 20,000 psi (350 kg/cm2 to 1400 kg/cm2) while passing an inert gas through, and maintaining an environment of said inert gas over, the roasted coffee and -the oil expressed therefrom. The roasted coffee is subjected to the oil expressing operation in a pressing means, typically any one of a large number of oil presses that are commercially available, while maintaining the temperature of the coffee during expressing at below about 175C and the temperature of the oil being expressed at between 25 and 50C. Preferably, the inert gas is carbon dioxide although other inert gases such as nitrogen may be employed either alone or in ~ . , ~ 5 ~ ~
combination with the carbon dioxide. A critical feature of the process is that the flow rate at which the ;nert gas is passed over the roasted coffee and the oil expressed therefrom should be maintained at between about 0.1 and 2.0 cfm (between about 47 and 944 cm3/sec.) within and surrounding the pressing means.
To sorne extent, the flow rate may be varied within the afore-mentioned limits, but care must be taken to ensure that the flow rate is maintained within such limits since the aroma principles are sought to be obtained in a balanced manner, i.e., controlled amounts of the low, medium and high boiling aromatics are desired. By regulating the flow rate of the inert gas within the pressing means, it is now possible to ~-control the quality and intensity of the aromas within the coffee oil that is expressed from the roasted coffee. Moreover, because of the balanced aromatics within the cofFee oil produced by the process of this invention, the coffee oil as well as the aroma principles contained therein are less costly to produce.
Thus, it is apparent that savings may be realized both in labor and energy as well as in raw materials, that is, the roasted coffee from which the coffee oil is expressed.
It should be mentioned that while inert gases have ~
previously been employed in the production of coffee oil having ~ -aroma principles therein, the use of such gases has been essentially for the purposes of serving as either a purging blanket or a transfer force. Thus, coffee oil has been obtained from roasted coffee by expelling the oil from the roasted coffee ~;
in an inert gas atmosphere so that the degradation of the coffee aromas by oxygen is prevented. Also, inert gases have -~
been employed to purge the headspace of vessels used to store coffee oil. As mentioned, inert gases have been further utilized as a transfer force so as to transport oil from the various , ~ o~i5~6, vessels and apparatuses utilized in coffee oil production and subsequent utilization of the coffee oil in the plating of soluble or instant coffee. Notwithstanding such conventional uses of inert gases in the production of coffee oil, the present discovery is predicated on the unexpected finding that by maintaining an inert gas atmosphere over the roasted coffee and the oil expressed therefrom and also passing such inert gas at a specified flow rate over the roasted coffee and the oil expressed therefrom, the aromatics within the coffee oil are able to be balanced much more carefully with the result that the coffee oil obtained has its aroma quality and intensity critically controlled. It is theorized that the process of the present invention results in a partial fractionation of the aroma principles of the coffee oil. It may also be noted that while maintaining and passing the inert gas over the ~ ~ -roasted coffee and the oil expressed therefrom lead to the -;
production of a coffee oil having balanced aromatic principles, -departure from the limits of flow rate results in unbalancing the aroma principles within the expressed coffee oil. Thus, if ;`
an insufficient flow rate of the inert gas is not ensured, then the deleterious effect of oxygen on the coffee oil and also ~;
an unbalancing of the aromatic principles therein may be noted.
Also, if the flow rate is permitted to exceed the limits which have been critically established, it appears that all of the aromatics may be effectively stripped from the expressed or expelled oil. In either case, then the aroma principles become unbalanced which is undesired.
In operating the pressing means so as to express`the coffee oil from the roasted coffee, as mentioned previously, any of a variety of commercially available presses or oil expellers may be utilized. The roasted coffee from which the oil is to be expressed or expelled is passed in the form of particles into the pressing means. During the expressing - 4 ~
~i536S~;6 operation, a pressure is developed on the expelled cake or meal. Subsequently, the expelled cake or meal may be extruded and cut into pellets for reintroduction into percolators with normal roasted and ground coffee from which the soluble or instant coffee is being produced and which may be later plated with the oil expressed from the roasted coffee by the process of this invention. During operation of the pressing means, it is desirable to cool the roasted coffee from which the coffee oil is being expelled so that the aromatic principles do not become degraded by exposure to inordinately high tempe-ratures which may be developed during the expressing operation.
The expressed coffee oil is discharged from the pressing means and its temperature upon discharge in the range of from about 25 to 50 C. The expressed coffee oil may be then immediately cooled and clarified as, for example, by centrifuging. The coffee oil, having balanced aroma principles as obtained by the process of the present invention, may be plated onto soluble or instant coffee in amounts of from about 0.1 to about 1%, by weight, based on the soluble or instant coffee powder. As mentioned previously, however, the coffee oil may have its aroma principles enhanced or increased by recovering the aroma principles from a given quantity of coffee oil and subsequently incorporating the concentrated aroma principles in another quantity of coffee oil, thereby increasing the overall concentration of aroma principles in the latter quantity bf coffee oil. The inert gas, particularly carbon dioxide, may be introduced into the pressing means by any ;~
suitable device such as gas nozzles.
In order that the present invention may be more fully understood, but without in any way attempting to limit it thereto, the following illustrative example is furnished.
, , - . . . .
.' : .
:. , . ' ~ .
~3~i5~
EXAMPLE
An Anderson* expe11er was charged with roasted whole coffee beans and the feed rate of the roasted coffee to the expeller was maintained at 300 pounds per hour. During the operation of the expeller, the temperature of the roasted coffee within the expeller was controlled to 160 C., the temperature of the coffee oil expressed was noted to be 30 C. During operation of the expeller9 carbon dioxide gas was admitted into and shrouded the expeller at a flow rate of 0.3 cfm (142 cm3/
sec.). The run was allowed to continue for 16 hours and the coffee oil expressed from the roasted coffee was recovered and analysed by gas chromatographic methods at hourly intervals following the start-up of the expeller. A similar run was made - ~ -on the same equipment utilizing the same type of roasted coffee, `- !~
feed rates and other conditions except that the flow rate of carbon dioxide gas was 2.5 cfm, the coffee oil was similarly recovered and analysed. A third run was made on the same equipment utilizing the same type of roasted coffee, feed rates and other conditions except that there was no admission of, or blanketing with, carbon dioxide, the coffee oil was similarly `~
recovered and analyzed. From the gas chromatographic data, it was found that the coffee oil expressed by the process of the present invention from roasted coffee produced a more balanced aroma blend and more desirable aroma principles than the coffee `~-oil obtained in either of the other runs. This finding was further confirmed when the coffee oil from each of the runs was subsequently plated onto soluble coffee powder and the oil-plated -~
soluble coffee powders were evaluated by an expert aroma panel.
'~
* Manufacturer's name ~ -,,,~ , , - ,,
Claims (2)
1. A process of obtaining coffee oil having aroma principles useful in the aromatization of foodstuffs which comprises expressing coffee oil from roasted coffee by subjecting said coffee to a pressure of from 5,000 to 20,000 psi (from 350 to 1400 kg/cm2) while passing carbon dioxide through at a flow rate of from 0.1 to 2.0 cfm (from 47 to 944 cm3/sec) and maintaining an environment of said carbon dioxide over the roasted coffee and the oil expressed there-from and maintaining the temperature of said coffee during expression at below about 175°C and the temperature of the oil being expressed at between about 25°C and 50°C.
2. The process as in claim 1 further comprising stripping the aroma principles from the expressed oil by distilling the expressed oil at subatmospheric pressures and under mild temperatures and condensing the separated aroma principles.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA267,753A CA1086556A (en) | 1976-12-13 | 1976-12-13 | Process of obtaining coffee oil from roasted coffee |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA267,753A CA1086556A (en) | 1976-12-13 | 1976-12-13 | Process of obtaining coffee oil from roasted coffee |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1086556A true CA1086556A (en) | 1980-09-30 |
Family
ID=4107488
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA267,753A Expired CA1086556A (en) | 1976-12-13 | 1976-12-13 | Process of obtaining coffee oil from roasted coffee |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1086556A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4335321A1 (en) * | 1993-10-15 | 1995-04-20 | Joachim Brimmer Ingenieurbuero | Process for extracting coffee oil-containing aroma constituents |
-
1976
- 1976-12-13 CA CA267,753A patent/CA1086556A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4335321A1 (en) * | 1993-10-15 | 1995-04-20 | Joachim Brimmer Ingenieurbuero | Process for extracting coffee oil-containing aroma constituents |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry | ||
| MKEX | Expiry |
Effective date: 19970930 |