Grinder Cleaner
20190029285 ยท 2019-01-31
Assignee
Inventors
Cpc classification
A23F5/267
HUMAN NECESSITIES
B08B9/00
PERFORMING OPERATIONS; TRANSPORTING
A23F5/02
HUMAN NECESSITIES
International classification
Abstract
A method for producing a grinder cleaner for cleaning food residue from a food processing grinder is disclosed. The method includes processing green coffee beans to form depleted coffee beans, wherein the depleted coffee beans have enhanced cleaning characteristics that allow the depleted coffee beans to clean food residue from the food processing grinder upon grinding of the depleted coffee beans. In one embodiment, the grinder cleaner is for cleaning a coffee grinder.
Claims
1. A method for producing a grinder cleaner for cleaning food residue from a food processing grinder, the method including processing green coffee beans to form depleted coffee beans, wherein the depleted coffee beans have enhanced cleaning characteristics allowing the depleted coffee beans to clean food residue from the food processing grinder upon grinding of the depleted coffee beans.
2. The method of claim 1, wherein processing the green coffee beans includes: extracting active components from the green coffee beans to produce processed green coffee beans; and drying the processed coffee beans to form the depleted coffee beans.
3. The method of claim 2, wherein extracting active components from the green coffee beans includes one or more of the following processes: aqueous extraction; acidic or alkaline aqueous solution based extraction; extraction by a volatile alcohol, including extraction by methanol, ethanol or isopropanol; organic solvent extraction; extraction by an oxidising or reducing agent; extraction by an enzyme or biological agent; extraction by a surface-active agent; super or sub-critical fluid extraction; or distillation based extraction.
4. The method of claim 3, wherein extracting the active components from the green coffee beans further includes expanding the green coffee beans to form expanded beans of increased physical size.
5. The method of claim 4, wherein expanding the green coffee beans assists in the extraction of active components from the green coffee beans.
6. The method of claim 4, wherein expanding the green coffee beans includes soaking the green coffee beans in a liquid to cause them to swell.
7. The method of claim 2, wherein drying the processed coffee beans includes one or more of the following processes: conventional oven/heated drying; microwave drying; freeze-drying; super or sub-critical fluid drying; ambient drying; chemical drying by a water absorbing material; modified pressure drying; or puffing.
8. The method of claim 1, wherein the formed depleted coffee beans have a moisture content less than or about 4%.
9. The method of claim 8, wherein the moisture content is less than or about 1%.
10. The method of claim 1, wherein the formed depleted coffee beans have a hardness of less than or about 125 N.
11. The method of claim 10, wherein the hardness is less than or about 75 N.
12. The method of claim 1, wherein the formed depleted coffee beans have a hardness no harder than the original coffee beans.
13. The method of claim 1, wherein the formed depleted coffee beans have a percentage size increase of about or greater than 50%.
14. The method of claim 13, wherein the percentage size increase is about or greater than 75%.
15. The method of claim 1, wherein the formed depleted coffee beans have a reduction in extractable fat content of about or greater than 50%.
16. The method of claim 15, wherein the reduction in extractable fat content is about or greater than 90%.
17. The method of claim 1, wherein the formed depleted coffee beans have a density of less than or about 0.5 g/cm.sup.3.
18. The method of claim 17, wherein the density is less than or about 0.4 g/cm.sup.3.
19. A grinder cleaner comprising the depleted coffee beans formed by the method of claim 1.
20. A method for cleaning food residue from a food processing grinder including: introducing the grinder cleaner of claim 19 into the food processing grinder; grinding the depleted coffee beans; and purging the ground depleted coffee beans from the grinder.
21. The method of claim 20, wherein the food processing grinder is a coffee grinder.
Description
BRIEF DESCRIPTION OF DRAWINGS
[0052] Embodiments of the present disclosure will be discussed with reference to the accompanying drawings wherein:
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[0061] In the following description, like reference characters designate like or corresponding parts throughout the figures.
DESCRIPTION OF EMBODIMENTS
[0062] Referring now to
[0063] The term depleted coffee bean(s) as used throughout the specification is defined to be a green coffee bean that has had its active components substantially extracted or removed yet with the processed coffee bean still substantially maintaining the same structural/physical integrity of the original green coffee bean. In this context, relevant active components include one or more of oils, fats, carbohydrates, proteins, sugars, polyphenols, flavonoids and other phytochemicals, including alkaloids such as caffeine.
[0064] The Applicant has recognised that, as an example, a coffee grinder is optimised to grind coffee beans and so coffee beans that have been suitably processed to form depleted coffee beans, having enhanced cleaning characteristics, will optimally clean the coffee grinder by a combination of physical removal and adsorption of the coffee residue from the grinding components of the coffee grinder. In one non-limiting example, a grinder cleaner formed in accordance with the present disclosure may be added to the coffee bean hopper of a domestic, commercial or super-automatic coffee machine, ground through the grinding burrs and in the process remove residual foodstuffs in the form of coffee residue typically consisting of oils, fats, carbohydrates, protein, polyphenols, flavonoids and other phytochemicals including caffeine and particulates from the grinding surfaces.
[0065] As would be appreciated, a depleted coffee bean may also be employed in other types of food processing grinders including, but not limited to, salt and pepper grinders, spice grinders, herb grinders, cheese grinders and meat grinders.
[0066] In one example, the green coffee beans are Robusta or Arabica coffee beans or a blend of these types.
[0067] Referring now to
[0068] Examples of different extraction processes that may be employed include, but are not limited to, one or more of:
[0069] water extraction;
[0070] extraction employing acidic or alkaline aqueous solutions;
[0071] volatile alcohol based extraction including, but not limited to, methanol, ethanol or isopropanol (under ambient or modified pressure conditions);
[0072] extraction employing surface-active agents including, but not limited to, structural derivatives of the following surfactant types: alkyl sulfates; alkyl sulfonates; alkyl succinates; alkyl sarcosinates; alkyl polyglycosides; alkyl amines; alkyl alkanolamides; alkyl amine ethoxylates alkoxylated alcohols; N-alkyl quaternary ammonium compounds; alkyl amidopropyl betaines; alkyl aminopropyl sultaines; or alkyl amine oxides;
[0073] extraction employing enzymes, or functional biological products, to assist in modifying the chemical composition of the bean, including but not limited to, protease, lipase, amylase or pectinase enzymes
[0074] extraction employing oxidising or reducing agents including, but not limited to, hydrogen peroxide; organic peroxides, such as peroxy acetic acid, phthalimido peroxyhexanoic acid or nonanoyloxy benzenesulfonate; inorganic oxidisers or activators, such as potassium monopersulfate or manganese (II) oxalate; or reducing agents, such as sodium metabisulfite or hydroxylamine hydrochloride;
[0075] supercritical fluid (SCF) extraction including, but not limited to the use, or combined use, of, CO.sub.2, water, methane, acetone, short-chain aliphatic alcohols, and short-chain saturated or unsaturated hydrocarbons, such as, but not limited to, ethane, propane, butane, ethylene, propylene etc.;
[0076] organic solvent extraction including, but not limited to, the use of hexane, pentane, petroleum fractions/distillates, acetone, diethyl ether, ethyl acetate, dialkyl ethers, halogenated methanes or hydrocarbons; or
[0077] extraction involving distillation, including steam, vacuum or other forms.
[0078] Each of the above extraction processes or combination of processes may also be undertaken under modified pressure conditions, including employing negative or positive pressure in the extraction process as required.
[0079] As would be appreciated, different considerations will govern which extraction process or combination of process are selected including energy use considerations, equipment costs, the desire to avoid particular ingredients, local regulatory requirements, the ability to selectively extract components from the green coffee beans and/or overall expected throughput. As a general comment, solvents will generally be used in pure or neat form, however, in the case of acidic or alkaline aqueous solutions, concentrations of between 2% and 4% have proven effective in producing depleted green beans to provide the desired physicochemical properties.
[0080] Referring again to
[0081] Examples of different drying processes that may be applicable include, but are not limited to one or more of:
[0082] conventional oven/heated drying, including, but not limited to, commercial dehydrators or convection ovens;
[0083] microwave drying;
[0084] freeze drying;
[0085] super or sub-critical fluid drying;
[0086] ambient drying, in contained areas or open to sunlight and environmental elements;
[0087] modified pressure drying, for example, drying under reduced pressure;
[0088] chemical drying, using desiccating materials or solvents able to absorb water; or
[0089] puffing, as employed in food production such as processing of cereals.
[0090] As with extraction processes, different considerations will determine which drying process or combination of drying processes are selected. Where process time is not critical, ambient drying processes may be more attractive. In other circumstances, the use of puffing processes involving a rapid pressure change that causes the release of trapped moisture and subsequent expansion of the processed coffee bean to produce a dry puffed depleted coffee bean of increased physical size may be applicable. In other circumstances, other techniques such as oven, microwave, chemical or reduced pressure drying may be more applicable, as well as those processes which are more energy intensive, such as freeze-drying and supercritical fluid drying.
[0091] Referring now to
[0092] In these examples, the expansion step functions to expand or swell the size of the green coffee bean but still substantially maintain the structural integrity of the bean. This typically results in a processed coffee bean having enhanced cleaning characteristics in the form of a depleted coffee bean having reduced compressive strength, ie more brittle, and hence more readily ground by the grinding surfaces of the food processing grinder which can reduce the potential for clogging depending on the grinding mechanism. In addition, the expansion process will generally assist the extraction of active components in the extraction process.
[0093] Some example methods for producing a grinder cleaner will now be described.
Method 1 (Hot Water, 2% Aqueous KOH, Citric Buffer, Freeze Drying)
[0094] Referring now to
[0095] The extraction process 330 involves a 2% aqueous KOH solution being added to the expanded beans and allowed to stand (60 C., 2-12 h). The solid is filtered carefully and soaked in cold water for 10 mins. To the resulting brown beans a 5% citric/citrate buffer (pH 5) is added and allowed to stand for 2-12 hours at room temperature. The beans are collected by filtration and cold water added, which is allowed to stand for 15 mins. This process functions to remove the KOH solution and then correct the pH of the processed green coffee bean to that of a regular coffee bean, ie pH of around 5-6.
[0096] Following the extraction of active components 210, the processed coffee beans are filtered and then dried 210, under standard commercial freeze drying conditions, to produce a depleted coffee bean having a moisture content of less than 5%. In other embodiments, the moisture content may be reduced to less than 1%.
[0097] In summary, Method 1 accordingly involves processing green coffee beans by:
[0098] expanding the green coffee beans by soaking in heated water;
[0099] extraction of active components from the expanded green coffee beans employing an aqueous alkaline solution and then an acidic solution to produce processed green coffee beans; and
[0100] drying the processed green coffee beans by freeze drying to form the depleted coffee beans for cleaning food residue from a food processing grinder.
[0101] This process has been found by the Applicant to generate consistent and reproducible depleted coffee beans where the freeze-drying maintains the expanded or swollen structure of the bean that is generated by soaking in hot water. This creates a lower density product (=0.4 g/cm.sup.3) that displays low compressive strength and which is of an appropriate brittleness suitable for use in a coffee grinder.
Method 2 (Hot Water, Hot 3.5% Aqueous Sodium Hydroxide, Cold Aqueous Buffer, Freeze Drying)
[0102] Referring again to
[0103] Cold softened water is then added to the beans, followed by 50% NaOH solution in proportion to generate a 3.5% aqueous solution and allowed to stir at 60-70 C. for a period of 2-12 hours. The solid is then filtered carefully and soaked in cold water for 30 minutes. The solution is decanted, with sieving, and discarded. To the resulting beans, a 5% citric/citrate buffer (pH 5) is then added and allowed to stand for 1 hour at room temperature. Following this step, the solution is decanted, with sieving, cold water added and allowed to stand for 30 minutes.
[0104] The beans are then collected and freeze-dried to produce a depleted coffee bean having a moisture content of less than 1%.
[0105] In summary, Method 2 accordingly involves processing green coffee beans by:
[0106] expanding the green coffee beans by soaking in heated softened water;
[0107] extraction of active components from the expanded green coffee beans employing an aqueous alkaline solution and then an acidic solution to produce processed green coffee beans; and
[0108] drying the processed green coffee beans by freeze drying to form the depleted coffee beans for cleaning food residue from a food processing grinder.
[0109] As would be appreciated, the process of freeze drying is chiefly used to dry and preserve the structural integrity of delicate or sensitive material. In this example, the process of freeze drying will allow the depleted coffee beans to substantially retain their expanded state as it minimises the tendency of the processed beans to contract upon drying which may occur under alternative drying conditions.
Method 3 (Hot Water, 2% Aqueous KOH, Citric Buffer, Microwave Drying)
[0110] Referring now to
[0111] Following the extraction of active components 210, the processed coffee beans are filtered and then dried 210 by in this embodiment spreading the processed coffee beans evenly in a single layer across a glass tray before being irradiated in a microwave oven. The intensity and length of irradiation will depend on the type of microwave source. For a typical commercial microwave oven having a power output of 1900 W, it has been found that a drying time of 8 minutes is required at 100% intensity to produce a coffee bean having a moisture content of less than 6%. As would be appreciated, for a commercial dryer using a microwave source, the drying time will vary depending on the required temperature, ramping rate and microwave surface power density.
[0112] In summary, Method 3 accordingly involves processing green coffee beans by:
[0113] expanding the green coffee beans by soaking in heated softened water;
[0114] extraction of active components from the expanded green coffee beans employing an aqueous alkaline solution and then an acidic solution to produce processed green coffee beans; and
[0115] drying the processed green coffee beans by microwave drying to form the depleted coffee beans for cleaning food residue from a food processing grinder.
[0116] In contrast to the other methods of drying, microwave drying has been found to require tighter process control in relation to the drying parameters so as not to overcook the processed green beans which in itself may produce unwanted flavour compounds and reducing the effectiveness of the depleted coffee beans as a grinder cleaner.
Method 4 (Hot Water, Ethanol, Convection Oven Drying)
[0117] Referring now to
[0118] The extraction process 330 involves adding ethanol at 95% or absolute concentration in the proportion of 2 L for every kilogram of coffee beans and the solution is allowed to stand for 15 minutes. The ethanol is decanted and replaced every 20 minutes for 1 hour before the beans are filtered.
[0119] Following the extraction of active components 210, the processed coffee beans are filtered and then dried 210 by employing a conventional fan forced oven operating at 103 C. for a period of 3 hours, or until the analysed moisture content is less than 4%. The dried depleted coffee beans are then allowed to cool to room temperature.
[0120] In summary, Method 4 accordingly involves processing green coffee beans by:
[0121] expanding the green coffee beans by soaking in heated water;
[0122] extraction of active components from the expanded green coffee beans employing an alcohol based solution to produce processed green coffee beans; and
[0123] drying the processed green coffee beans by convection drying to form the depleted coffee beans for cleaning food residue from a food processing grinder.
[0124] The Applicants have found that the addition of ethanol to the expanded beans facilitates some degree of water removal by solvent exchange both outside and within the bean structure. Three successive stages of soaking and decanting with ethanol were also found to allow for greater desiccation of the final product, and greater retention of the expanded bean structure. This method can also be included as an additional step in other production methods as a way of reducing the water content prior to any final drying stage or stages.
Method 5 (Water, Ethanol, Supercritical CO.SUB.2 .Extraction)
[0125] Referring now to
[0126] Similar to Method 4, the initial extraction process 330A involves adding ethanol at 95% or absolute concentration in the proportion of 2 L for every kilogram of coffee beans and the solution is allowed to stand for 15 minutes. The ethanol is decanted and replaced every 20 minutes for 1 hour.
[0127] Following this initial extraction process, the beans are then subjected to supercritical CO.sub.2 extraction 330B, with either neat CO.sub.2 or a CO.sub.2 co-solvent mixture, where the co-solvent can be any additive that is miscible in supercritical CO.sub.2 and included for the purpose of modifying the solubility of target chemical compounds. Ideally, a 95:5 mixture of CO.sub.2/alcohol can be used, where the alcohol may be any aliphatic alcohol, but preferably ethanol or isopropanol.
[0128] A stepped method of increasing pressure, up to a potential maximum of 1000 bar, but more likely up to 600 bar, may be used to extract a broad range of target compounds, at temperatures not exceeding 100 C. A final extraction using neat CO.sub.2 is used to purge the beans of any co-solvent, after which slow release of the pressure within the vessel ensures the structural integrity of the bean is maintained. This also results in a concurrent initial drying process as water is miscible with the supercritical CO.sub.2 and will be removed by this final extraction or purging process.
[0129] Following the extraction of active components 330B and the associated drying, the processed coffee beans are filtered and then dried 210 at standard temperature and pressure for 1 hour.
[0130] In summary, Method 5 accordingly involves processing green coffee beans by:
[0131] expanding the green coffee beans by soaking in heated water;
[0132] extraction of active components from the expanded green coffee beans in a first stage employing an alcohol based solution and then in a second stage by supercritical CO.sub.2 extraction to produce processed green coffee beans; and
[0133] drying the processed green coffee beans in an initial stage as a result of the supercritical CO.sub.2 extraction followed by a final stage of ambient drying to form the depleted coffee beans for cleaning food residue from a food processing grinder.
[0134] An advantage of this method of extraction is that a broad range of materials, free from chemical modification or cross-contamination, may be individually extracted. Selected co-solvents in supercritical fluids may be employed to tailor the extraction conditions to particular chemical compounds that have low, or limited, solubility in supercritical CO.sub.2. In addition, the process efficiency may be fine-tuned by modifying the mixtures of supercritical solvents, via temperature, pressure and time process modifications, to gain maximum extraction yield with minimal input of time, energy and materials.
[0135] As would be appreciated, this process allows the extract by-product to be potentially on-sold to producers of food products.
[0136] In other embodiments, the supercritical extraction conditions may be optimised to remove the need for initial water and ethanol extraction steps, ie the expansion and extraction may be achieved using different stages of the supercritical process. In this case, expansion, extraction and drying would occur in-situ without additional processing.
Method 6 (Water, Super- or Sub-Critical Fluid Extraction)
[0137] Referring now to
[0138] The extraction process 330 involves supercritical fluid extraction, using supercritical fluids that do not include CO.sub.2, e.g. short-chain hydrocarbon mixtures. A method of stepwise increase in vessel pressure, similar to that of supercritical CO.sub.2 extraction, is used to extract a broad range of target compounds. For the drying process 210, removal of water is achieved with positive solvent flow through the vessel during extraction.
[0139] In summary, Method 6 accordingly involves processing green coffee beans by:
[0140] expanding the green coffee beans by soaking in heated water;
[0141] extraction of active components from the expanded green coffee beans employing a supercritical fluid to produce processed green coffee beans; and
[0142] drying the processed green coffee beans by use of the supercritical fluid to form the depleted coffee beans for cleaning food residue from a food processing grinder.
[0143] As would be appreciated, the above methods and processes may be varied in accordance with the desired characteristics of the grinder cleaner that is to be produced. In terms of the extraction of active components this may involve extracting a broad range of compounds in single extraction process or alternatively a series of targeted extraction processes may be employed in succession each directed to certain individual or classes of compounds which in combination will extract a broad range of compounds. This process may be beneficially employed to then extract a particular compound as an individual component for further commercial exploitation. Although typically the expansion step occurs prior to extraction, it can be performed after extraction and in some case may be combined with the extraction process.
[0144] Depleted coffee beans may be formed in accordance with the present disclosure so as to have a percentage size increase as compared to the original coffee beans in the range, including but not limited to, of less than 10%, 10%-20%, 20%-30%, 30%-40%, 40%-50%, 50%-60%, 60%-70%, 70%-80%, 80%-90%, or 90%-100%. In one example, the percentage size increase of the depleted coffee beans formed in accordance with the above described processes is about or at least 50%. In another example, the percentage size increase of the depleted coffee beans formed in accordance with the above described processes is about or at least 75%.
[0145] Depleted coffee beans may be formed in accordance with the present disclosure so as to have a moisture content in the range, including but not limited to, of less than 1%, 1%-2%, 2%-3%, 3%-4%, 4%-5%, 5%-6%, 7%-8%, 9%-10%, 10%-11% or 11%-12%. In one example, the moisture content of the depleted coffee beans formed in accordance with the above described processes is reduced to less than or about 4%. In another example, the moisture content of the depleted coffee beans formed in accordance with the above described processes is reduced to less than or about 1%.
[0146] Depleted coffee beans may be formed in accordance with the present disclosure so as to have a hardness, as measured by a tablet hardness tester, in the range of, including but not limited to, of less than 50 N, 50 N 75 N, 75 N 100 N, 100 N 125 N or 125 N 150 N. In one example, the hardness of the depleted coffee beans formed in accordance with the above described processes is less than or about 125 N. In another example, the hardness of the depleted coffee beans formed in accordance with the above described processes is less than or about 75 N. As would be appreciated, correct orientation of the depleted coffee bean in the testing equipment is recommended in order to achieve accurate and reproducible hardness results.
[0147] Depleted coffee beans may also be formed in accordance with the present disclosure so as to have a hardness no harder than the original green been or formed to have a hardness approximating that of a commercially supplied roasted coffee bean.
[0148] Depleted coffee beans may be formed in accordance with the present disclosure so as to have a density in the range of, including but not limited to, less than 0.25 g/cm3, 0.25 g/cm3-0.30 g/cm3, 0.30 g/cm3-0.35 g/cm3, 0.35 g/cm3-0.40 g/cm3, 0.40 g/cm3-0.45 g/cm3 or 0.45 g/cm3-0.50 g/cm3. In one example, the density of the depleted coffee beans formed in accordance with the above described processes is less than or about 0.5 g/cm3. In another example, the density of the depleted coffee beans formed in accordance with the above described processes is less than or about 0.4 g/cm3.
[0149] The depleted coffee beans may be formed in accordance with the present disclosure to have a percentage weight for weight oil or fat content range of, as measured in accordance with either the standard Association of Official Analytical Chemists (AOAC) soxhlet method (1995, various solvent choices), Weibull-Stoldt method or Werner-Schmid method, including but not limited to, of less than 1.0%, 1.0-2.0%, 2.0-3.0%, 4.0%-5.0%, 5.0%-7.5%, 7.5%-10%.
[0150] Alternatively, this may be expressed in terms of a reduction in the total extractable oil content of a green coffee bean. In one example, the reduction in the total extractable oil content of the depleted coffee beans formed in accordance with the above described processes is greater than or about 50%. In another example, the reduction in the total extractable oil content of the depleted coffee beans formed in accordance with the above described processes is greater than or about 90%.
[0151] Throughout the specification and the claims that follow, unless the context requires otherwise, the words comprise and include and variations such as comprising and including will be understood to imply the inclusion of a stated integer or group of integers, but not the exclusion of any other integer or group of integers.
[0152] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement of any form of suggestion that such prior art forms part of the common general knowledge.
[0153] It will be appreciated by those skilled in the art that the disclosure is not restricted in its use to the particular application described. Neither is the present disclosure restricted in its preferred embodiment with regard to the particular elements and/or features described or depicted herein. It will be appreciated that the disclosure is not limited to the embodiment or embodiments disclosed, but is capable of numerous rearrangements, modifications and substitutions without departing from the scope of the invention as set forth and defined by the following claims.