DE2354525A1 - PROCESS FOR FLAVORING SOLUBLE DRIED COFFEE EXTRACT - Google Patents

Description

PATENT LAWYERS

DR-ING. FROM KHSISLSR DR.-ING. SC HON FOREST DR.-ING. TH. MEYER DR. FUES DIPL-CHEM. ALEK VON KREISLER DIPL.-CHEM. CAROLA KELLER DR.-ING. KLOPSCH DIPL-ING. SELTING

COLOGNE 1, DEICHMANNHAÜS

Cologne, October 30th Fu / Ax

GENERAL FOODS CORPORATION 250 North Street, White Plains, New York (U.S.A.).

Process for flavoring soluble dried;

Coffee extract

The grinding gas, i.e. the gas that is released from roasted whole coffee beans when their internal cell structure is torn during the grinding of the coffee beans, for example, and that from the torn and / or crushed beans "continue for a short time subsequently developed has long been recognized as a highly desirable natural coffee flavor. That However, capturing and stabilizing this aroma proved to be a difficult endeavor, especially if this is to be done in a large-scale plant for the production of soluble coffee.

The use of grinding gas as a means of increasing the The aroma of soluble coffee powder in the vessel is described in US Pat. No. 3,021,218, where the headspace of the vessel3 is flavored, and in U.S. Patent 2,306,061, where the flavors of the milling gas are cooled to soluble Coffee powder are condensed, described. The use of condensates of the grinding gas, which is a liquid Extract can be added and dried to improve the flavor of the drink in the lasse upon dissolution of the Achieving powder in hot water is used in the USA

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U.S. Patent 3,244,533. According to this patent, coffee oil is homogenized in the extract, whereupon condensed flavorings of the grinding gas are added. Condensed milling gas can be mixed with a liquid glyceride be mixed. The mixture can then undergo treatment to remove excess water, e.g. Centrifugation, be subjected to before it becomes liquid Coffee extract is added, which is then frozen and freeze-dried.

The subject of the invention is the aromatization of coffee extract according to a process which is characterized in that the gas, which is released when the cell structure of freshly roasted coffee is torn apart, is passed in a turbulent flow downwards through a standing one to a temperature below -8o C cooled scraper cooler with such a flow rate that most of the gas is condensed, the condensate removed from the wall of the scraper cooler so that it falls to the bottom of the heat exchanger, and with a liquid glyceride in an amount of 0.5 to 5 parts by weight of condensate per part by weight of glyceride combined, the moisture from the mixture of condensate and glyceride to less than 0.5 wt -% combined removed and the resulting dehydrated mixture with the coffee extract..

The milling gas obtained by disrupting the cellular structure of freshly roasted coffee beans is supplied to the upper end of a vertical jacketed scratch cooler, for example, with a liquefied inert gas, for example, ₀ nitrogen (boiling point -196 ⁰ C) is cooled to a temperature below 80 ⁰ C "Before entering the V / ärmeaustauscher the grinding gas can be passed through a switched as the first stage capacitor having an upward flow, _o to condense a portion of the water vapor These upstream water removal is expedient of arbei- to capacity with downwardly directed flow

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tend to increase the scratch cooler.

The flow of the grinding gas to the heat exchanger is increased set such a low value that most of the preferably at least $ 75 of the gases and flavors are condensed, but the flow rate is kept so high that no substantial Oxygen quantities (boiling point -183 ° C) are liquefied. Avoid the formation of liquid oxygen as the explosive nature of the material could jeopardize safety. The mill gas stream The heat exchanger must be kept in the agitated or turbulent state so that it is less likely is that the gas is uncondensed particularly near the center of the usually cylindrical heat exchanger flows through the heat exchanger.

The grinding gas is in the heat exchanger as frost or snow condenses on a frozen surface which is scraped off in a known manner. The one from the exchanger wall Scraped frost falls through the bottom of the heat exchanger. This frost is then mixed with a liquid Glyceride mixed, and this liquid should then be given a treatment to remove excess water be subjected. It is also possible, both the grinding gas and the liquid glyceride, for example with a Spray nozzle for two liquids to spray the top of the heat exchanger, eliminating the need for a separate one Avoid mixing stage.

The flavored glyceride can either be mixed with dry soluble coffee, for example according to that in the US patent. Sputtering are described 3,148,070 combined or added to a liquid coffee extract or kaffeeartigem extract prior to drying the extract _o The aromatized glyceride may be, for example, solidified by freezing and then comminuted by grinding, for example, before it with the soluble coffee

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mixed in powder or with a liquid coffee extract, a liquid coffee extract containing water ice crystals or a partially frozen tablet of coffee extract.

The easiest way to obtain the grinding gas is to include or include the mills, e.g. large-scale mills be kept under a hood. The gases released from the ground coffee can be pumped or removed with a centrifugal fan. In addition, if desired, a stream of a preferably moisture-free Inert gases are used to drive off the gas from the coffee and complete the grinding process in an essentially one way To allow inert atmosphere to take place. One such method is shown in U.S. Patent 2,156 In this process, the gases evolved and given off during roasting are collected, however this method is equally applicable to the collection of gases released during milling or developed during the rupture of the cells of freshly roasted whole coffee beans. If with a Pump is sucked off, it can be useful to cool the gas before the pump, so that the pumping in addition The heat generated does not damage or degrade the flavoring substances contained in the gas.

Chemically, the evolved gas consists largely of carbon dioxide together with water vapor and the characteristic aromatic components of roasted coffee. The humidness in the gas can be achieved by using low-moisture green coffee, by roasting under dry

conditions and by using largely dry Ground quenching media lowered. The evolved gas is preferably passed through a first cooler where it is cooled to a temperature between 2 ° and 10 ° C, and where substantial amounts of water are removed. That proportionately low-moisture gas is then

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sheathed standing scraper cooler supplied with a Plüsaigas is cooled as a refrigerant, this part of the Processing equipment is well known to those skilled in the art.

Preferably 'the heat exchanger with liquid Nitrogen cooled and the amount of gas flowing into the heat exchanger in the range of about 3.05 to 15.15 1 /

Minute / dm heat exchange surface held. That from the cooling system discharged nitrogen gas can be used as an inert gas stream that is used elsewhere in the process Production of instant coffee, e.g. for driving the grinding gas out of the mills or when packing the soluble one Coffees can be used under inert gas.

The heat exchanger is usually cylindrical and with an annulus for the passage of the heat exchange medium serving liquefied gas. The gas containing the flavoring substances flows through from top to bottom passed the inner cylinder, which is the heat transfer wall represents. In the middle of this inner cylinder there is usually a rotating shaft on which a or several scratches are attached to the entire Brush the length of the heat transfer wall as the shaft rotates.

In a preferred embodiment of the invention the turbulence of the gas flow in the heat exchanger with the help of fan blades or other similar components, those on an inner rotating component, e.g. -. at the Scraper-bearing rotor shaft, attached, increased. These fan blades do not touch the wall of the heat exchanger and are only used to generate the turbulence in the gas flowing through the heat exchanger, particularly near the center of the cylinder. As a result of this increased turbulence, the probability is greater that the gas with the -cooled Wall of the heat exchanger comes into contact.

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The Ga3 containing the flavors is condensed to form a frost or snow when it hits the heat transfer wall of the heat exchanger comes into contact. The rotating scrapers scrape the condensate off the wall and the frost falls by gravity to the bottom or through the bottom of the heat exchanger, where it is connected to the subsequent Addition to a liquid glyceride is collected or mixed directly with the glyceride, the Frost can be kept at a low temperature for a short time with no adverse change, but it is preferable quickly with a liquid glyceride, e.g. a vegetable oil, coffee oil or triacetin, with a void taste mixed. Preferably, the frost is added to the glyceride in an amount of 0.5 "to 5 kg / kg of glyceride.

It has been found that the stability of the condensed flavors of the grinding gas is greatly increased when they can be combined with a glyceride carrier. Of course, the flavored glyceride "must be kept at a low temperature." if it is not used immediately.

Immediately after the condensed milling gas has been mixed with the liquid glyceride, the liquid is undergoing treatment to subdue to remove excess water. By removing water from the flavored The flavoring substances are preferably glyceride to a residual content of 0.5 GeWo $ or less of the grinding gas further stabilized. As in the German

Patent specification (patent application P 23 23 627.3)

described by the applicant, the centrifugation turned out to be Ultracentrifugation, molecular distillation and the use of desiccants as suitable methods for successfully removing water from the flavored Glyceride. As a further refinement of this removal of the water, it is possible to add any flavoring substances to separate from the removed water, for example by vacuum distillation and this separated aroma

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to add substances to the flavored glyceride again.

The flavored glyceride can be mixed with soluble coffee powder or with coffee extract before drying the extract by any known method or in the manner described in the Above-mentioned patent specifications of the applicant described manner are combined. The flavored Glyceride is generally used in an amount of 0.1 to 2% by weight based on the weight of the soluble pesticide in the end product. The flavored powder according to the invention can of course all of the powder or represent only part of the powder in the final product.

The terms "coffee powder" and "coffee extract" as used herein embrace materials that are exclusive of or partly from coffee substitutes, e.g. powders or extracts, which are wholly or * partly from roasted grain such as wheat, rye and barley have been preserved. An example of such a material is this Product with the trade name "Instant Postum", obtained by extracting wheat, barley and molasses with Water and drying the extract to obtain a powder is mentioned.

example

Several large-scale coffee grinders were covered with hoods that were connected to a manifold « During the grinding, 7.93 m of grinding gas / minute were obtained. That Gas was passed through a condenser entering at 27 ° C and exiting at 4.4 ° G. Here were 6.8 kg Water / hour removed. The gas was 6 standing scraped surface coolers which were arranged in parallel «200 l liquid nitrogen / hour were fed to each cooler, 4.54 kg of "frost" were formed per hour in each cooler.

The frost was mixed in a jacketed container, the jacket temperature of which was 16 to 21 ⁰ C, with cottonseed oil in an amount of 4 kg of frost per kg of oil.

4Q98 83 / U2.71 -.- · - · -.-'- ..>

Matted oil was centrifuged, taking 0.24 kg of water per liter of the flavored liquid have been removed. The flavored "dry" oil was frozen at -29 ° C. It was found to be stable at this temperature for at least 3 days.

The frozen oil was thawed in a tap water bath and then with coffee extract containing ice crystals (about 10 wt% ice cream) at a rate of 0.5 kg of flavored oil per 100 kg of soluble coffee solids mixed. The extract was then sprayed onto G-freezer belts where it was completely frozen. The frozen one Extract was ground and then freeze-dried. The obtained freeze-dried powder was in hot Dissolved in water. The drink developed a pleasant aroma of freshly roasted coffee.

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Claims (7)

Claims / Τ,) Method of flavoring soluble dried. Coffee extract by condensing the gas that is released by tearing the cell structure of freshly roasted coffee, and adding the condensate to the coffee extract, characterized in that the gas from the torn beans in a turbulent flow down through one to a temperature below -80 ⁰ C cooled standing scraper cooler with a flow rate at which most of the gas is condensed, the condensate is removed from the wall of the cooler and drops to the bottom of the heat exchanger and with a liquid glyceride in an amount of 0, 5 to 5 parts by weight of condensate per. Part by weight glyceride combines the moisture from the. Mixture of condensate and glyceride removed to a residual content of less than 0.5 wt .- ^ and the resulting low-moisture mixture combined with the coffee extract. 2) Method according to claim 1, characterized in that that the low-moisture mixture is added to an aqueous coffee extract, which is then freeze-dried will. 3) Method according to claim 1 ', characterized in that that the low-moisture mixture is added to a dried coffee extract. 4) Method according to claim 1 to 3 _t, characterized in that the heat exchanger is cooled with liquid nitrogen and the gas in an amount of 3 * 05 to 15.15 l / dm heat exchange
Introduces scratch cooler. ο
15.15 l / dm heat exchange surface per minute in the 40 9883/0271 5) Method according to claim 1 to A, characterized in that that the gas is passed through a cooler to remove water before it enters the heat exchanger is introduced. 6) Method according to claim 5, characterized in that the gas is cooled ^{to a temperature of 2 to 1O 0 O in the upstream cooler.} 7) Method according to claim 1 to 6, characterized in that the condensate from the wall through a Scraper scrapes, which rotates on a shaft in a cylindrical heat exchanger, and the gas through holds at least one fan blade rotated by the shaft in turbulent flow. 409883/0271