Method for producing non-aqueous composition

Abstract

A method for producing a non-aqueous composition; the present invention relates to a process for preparing a mixture of a liquid organic polyol and a structuring agent, comprising the following successive steps: i) heating a mixture of a liquid organic polyol and a structuring agent in a container to a temperature of 60 DEG C or higher, ii) adding abrasive and other non-flavoring ingredients to the mixture, iii) rapidly cooling the resulting mixture from a temperature above 60 DEG C using a heat exchanger at a cooling rate of 1 DEG C / min or higher, to form a paste or gel.

Description

TECHNICAL FIELD

[0001] The present invention relates to a method of manufacturing a non-aqueous composition. BACKGROUND

[0002] Non-aqueous paste compositions have proven difficult to produce as the rheology of the paste is difficult to control. The stability of non-aqueous pastes can also be problematic.

[0003] A problem with non-aqueous formulations such as those disclosed in WO 96 / 03108 is that their rheological behaviour is different from typical aqueous dentifrices. This problem is observed both during production and during use by the consumer. This leads to production difficulties and reduces acceptance by the consumer. Viscosity profile and flow characteristics are key factors governing the ease of processing of dentifrices, product performance and consumer perception.

[0004] EP 2 089 040 describes oral care compositions for remineralising damaged teeth and / or whitening teeth. The composition can be a biphasic composition comprising a source of calcium ions and a source of phosphate ions. It is preferred for such systems that the water content in the composition is low.

[0005] There remains a need for non-aqueous pastes, in particular oral care toothpastes, which have excellent rheological properties such as viscosity, are stable and preferably contain high levels of materials which can remineralise tooth enamel. SUMMARY

[0006] The present invention provides a method of manufacturing a non-aqueous composition comprising the following sequential steps: i) heating a mixture of a liquid organic polyol and structurant in a vessel to a temperature of 70°C or higher, ii) adding an abrasive and other non-flavour ingredients to the mixture; iii) rapidly cooling the resulting mixture from a temperature above 60°C using a heat exchanger at a cooling rate of 1 °C / minute or higher to form a paste or gel. DETAILED DESCRIPTION

[0007] Unless otherwise indicated in the examples or by context, all numbers expressing quantities of materials, reaction conditions, physical properties of materials, and / or use are to be understood as modified in all instances by the term "about".

[0008] All amounts are by weight of the composition, unless otherwise specified.

[0009] It should be noted that as any numerical range is specified herein, any upper value can be associated with any particular lower value.

[0010] If a particular feature is disclosed in connection with a particular aspect of the application, the disclosure of that feature in connection with that particular aspect is also to be considered disclosed in connection with all other aspects of the application (for example, the methods of the application).

[0011] Any natural or naturally derived ingredient referred to in the present application is from Europe.

[0012] The composition of the present application is preferably for cleaning the oral cavity surfaces and is an oral care composition. Thus, the preferred product form of the composition of the present application is suitable for brushing and / or rinsing the oral cavity surfaces.

[0013] The composition of the present application is most preferably in the form of a dentifrice. The term "dentifrice" refers to an oral composition used for cleaning the oral cavity surfaces. The composition is not intentionally swallowed for the purposes of systemic administration of a therapeutic agent, but rather is applied to the oral cavity for treatment of the oral cavity and then expectorated. Typically, the composition is used with a cleaning implement such as a toothbrush, and is typically applied to the bristles of the toothbrush which is then used to brush the surfaces of the oral cavity accessible to the bristles.

[0014] The dentifrice / toothpaste is preferably in the form of an extrudable semi-solid, such as a cream, paste or gel (or mixtures thereof).

[0015] The composition according to the present application (e.g. dentifrice / toothpaste) will typically comprise, in addition to the ingredients described above, other ingredients to enhance performance and / or consumer acceptance.

[0016] The rheology behaviour of the composition produced by this process can be well controlled to achieve the desired sensory effects. Another particular advantage of the composition of the present application is its storage stability.

[0017] The composition of the present application is non-aqueous. By "non-aqueous" is generally meant that no significant amount of water is intentionally added to the composition. However, the term "non-aqueous" does not mean that small amounts of water can not be present, for example as a result of its association with hygroscopic ingredients. Thus, for the purposes of the present application, the term "non-aqueous" generally means that the amount of water present is no more than about 5% by weight, more preferably no more than about 3% by weight, based on the total weight of the composition.

[0018] Polyol The composition of the present application comprises an organic polyol. Preferred polyols for use in the present application include organic polyols having 3 or more hydroxyl groups in the molecule (hereinafter referred to as "organic polyols"). Examples of such materials include glycerol, sorbitol, xylitol, mannitol, lactitol, maltitol, erythritol and hydrogenated partially hydrolysed polysaccharides. The most preferred organic polyol is glycerol. Mixtures of any of the above materials can also be used.

[0019] The amount of organic polyol depends on the particular type chosen, but is typically about 20 to 90% by weight, based on the total weight of the composition. A suitable range for the amount of organic polyol, based on the total weight of the composition, is 35 to 75%, more preferably 45 to 70%. Within the scope of the present invention, the term "organic polyol" means that the composition is not oil-based or water-based, but rather has an organic polyol (as defined above) as the primary ingredient in the composition. By "primary ingredient" is meant that the organic polyol (as defined above) is present in the composition in a greater amount by weight than any other compound. Ideally, the composition of the present invention is glycerol-based (i.e., glycerol is present in the composition in a greater amount by weight than any other compound), and contains 45 to 70% by weight of glycerol, based on the total weight of the composition.

[0020] Structurant The composition of the present invention comprises a structurant. A preferred structurant is one or more solid polyethylene glycol crystals having a melting point of 25°C or greater. Preferably, the melting point ranges from 35 to 65°C, more preferably from 55 to 60°C.

[0021] Polyethylene glycol has the general formula H(OCH2CH2) n OH, where n is the number of repeating oxyethylene units. Commercially available polyethylene glycols are not generally uniform compounds, but rather consist of a distribution of similar polymeric members of a homologous series of polyethylene glycols defined by an average value of n and molecular weight. The melting point generally increases with increasing average value of n and molecular weight. A suitable solid polyethylene glycol has an average value of n in the above general formula ranging from about 20 to 220, preferably from about 40 to 150, more preferably from about 32 to 90, most preferably from about 60 to 75. A suitable average molecular weight ranges from about 950 to 11,250, preferably from about 1800 to 6600, more preferably from about 1400 to 4400, most preferably from about 2700 to 3700 g / mol. Suitable commercially available materials include, for example, Polyglykol® 3000 (available from Clariant). Mixtures of any of the above materials can also be used.

[0022] A suitable range for the amount of solid polyethylene glycol (as defined above) in the composition of the present invention, based on the total weight of the composition, is 0.1 to 5%, preferably 0.5 to 3%, more preferably 1 to 2.5%.

[0023] An alternative structurant includes xanthan gum. Xanthan gum is a fermentation product made from carbohydrates by the bacterium Xanthomonas campestris Xanthomonas . Four species of Xanthomonas campestris Xanthomonas have been reported in the literature, namely Xanthomonas campestris X. campestris , X. phaseoli , X. malvocearum and Xanthomonas carotae (Pseudomonas carotae)X. carotae ) are the most efficient gum producing bacteria.

[0024] Xanthan gum is generally described as an anionic heteropolysaccharide with a primary structure consisting of repeating pentasaccharide units, each of which is composed of two glucose units, two mannose units, and one glucuronic acid unit. These repeating pentasaccharide units impart to xanthan gum its characteristic backbone, which consists of (1->4) beta-D-glucopyranosyl units, every other glucose residue of which is substituted at the C-3 position with a charged trisaccharide side chain. The trisaccharide side chain is composed of a D-glucuronic acid unit between two D-mannose units. Less than half (about 40%) of the terminal D-mannose residues contain a pyruvic acid residue, which is attached via a keto group to the 4 and 6 positions, while the D-mannose attached to the backbone mostly contains an acetyl group at the O-6 position. Some of the side chains can be missing. The acetic and pyruvic acid content of the side chains varies, depending on the bacterial strain used to produce the gum and the fermentation conditions.

[0025] Xanthan gum generally has a molecular weight of one million to fifty million. It generally has a viscosity of 850 to 1,700 mPa-s (using a 1% solution of gum in 1% KCl at 25°C, measured on a Brookfield LV viscometer at 60 rpm using a number 3 spindle).

[0026] Xanthan gum is available from a number of commercial suppliers, such as RT Vanderbilt Company and CP Kelco. Examples of suitable xanthan gums are Keltrol®, Keltrol® F, Keltrol® T, Keltrol® TF, Xantural® 180, and Vanzan® NF.

[0027] The amount of xanthan gum in the composition of the present application is preferably from 0.05 to 1.5 wt.%, more preferably from 0.1 to 0.9 wt.% (based on the total weight of the oral care composition).

[0028] Another embodiment of the present application comprises carrageenan as structurant. Preferably, the carrageenan is present in a weight ratio of iota (i) to kappa (k) of 1 : 2 to 2 : 1.

[0029] The carrageenan present in the composition of the present application preferably consists of a total content of 33 wt.% to 66 wt.% of iota carrageenan and 33 wt.% to 66 wt.% of kappa carrageenan.

[0030] The total content of carrageenan is from 0.05 to 1 wt.%, more preferably from 0.08 to 0.5 wt.%, most preferably from 0.05 to 0.25 wt.% of the total composition.

[0031] Mixtures of structuring agents can be used.

[0032] Remineralization agent In one embodiment, the preferred type of oral care active ingredient included in the compositions of the present application includes a tooth remineralization agent. Within the context of the present application, the term "remineralization" refers to the in situ formation of hydroxyapatite on the teeth.

[0033] A specific example of a suitable agent for tooth remineralization is a mixture of a calcium source and a phosphate source that, upon delivery to the teeth, forms hydroxyapatite in situ on the teeth.

[0034] Illustrative examples of the types of calcium sources (hereinafter referred to as "remineralization calcium sources") that can be used herein include, for example, calcium phosphate, calcium gluconate, calcium oxide, calcium lactate, calcium glycerylphosphate, calcium carbonate, calcium hydroxide, calcium sulfate, calcium carboxymethylcellulose, calcium alginate, calcium salts of citric acid, calcium silicate, and mixtures thereof. Preferably, the remineralization calcium source is calcium silicate.

[0035] The amount of one or more remineralization calcium sources (e.g., calcium silicate) is typically from 1 to 30%, preferably from 5 to 20%, based on the total weight of the oral care composition.

[0036] Illustrative examples of the types of phosphate sources (hereinafter referred to as "remineralization phosphate sources") that can be used herein include, for example, monosodium dihydrogen phosphate, disodium hydrogen phosphate, sodium pyrophosphate, tetrasodium pyrophosphate, sodium tripolyphosphate, sodium hexametaphosphate, potassium dihydrogen phosphate, trisodium phosphate, tripotassium phosphate, and mixtures thereof. Preferably, the remineralization phosphate source is a mixture of trisodium phosphate and monosodium dihydrogen phosphate.

[0037] The total weight content of one or more remineralization phosphate sources (e.g., trisodium phosphate and monosodium dihydrogen phosphate) in the compositions of the present application is typically from 2 to 15%, preferably from 4 to 10%, based on the total weight of the oral care composition.

[0038] Mixtures of any of the above materials can also be used.

[0039] Other ingredients The compositions of the present application, particularly toothpastes, preferably comprise a particulate abrasive material, such as silica, alumina, calcium carbonate, dicalcium phosphate, calcium pyrophosphate, hydroxyapatite, trimetaphosphate salt, insoluble hexametaphosphate salt, and the like, including agglomerated particulate abrasive materials, typically in an amount of from 3 to 60% by weight of the oral care composition.

[0040] Preferably, the composition, in particular toothpaste, comprises a silica based abrasive. A preferred abrasive silica for use in the present application is a low refractive index silica. This can be used as the sole abrasive silica or together with a low level of other abrasive silicas such as described in EP 236 070. The low refractive index silica used as an abrasive in the present application is preferably a silica having an apparent refractive index (R.I.) in the range of 1.41 to 1.47, preferably 1.435 to 1.445, preferably having a weight average particle size of 5 to 15 mm, a BET (nitrogen) specific surface area of 10 to 100 m 2 / g and an oil absorption of about 70 to 150 cm 3 / 100 g, although lower refractive index abrasive silicas can also be used. Typical examples of suitable low refractive index abrasive silicas (e.g. R.I. of 1.435 to 1.445) include: Tixosil 63 and 73 available from Rhone Poulenc; Sident 10 available from Degussa; Zeodent 113 available from Zeofinn; Zeodent 124 available from Evonik; Sorbosil AC 77 (R.I. of about 1.440) available from PQ Corporation. These silicas are typically used in the composition in amounts of 5 to 60 wt%, typically 5 to 20 wt%.

[0041] The composition, in particular toothpaste, preferably comprises an inorganic or natural or synthetic thickening or gelling agent in a proportion of about 0.10 to about 15 wt% depending on the material selected. These proportions of thickening agent in the dentifrice compositions of the present application form an extrudable, shape-retaining product which can be extruded from a tube onto a toothbrush without falling between the bristles but instead retaining its shape substantially thereon. Suitable thickening or gelling agents which can be used in the present application include inorganic thickening silicas such as amorphous silica sold under the trade name Zeodent 165 by Huber Corporation, Irish Moss, iota-Carrageenan, Tragacanth and polyvinylpyrrolidone.

[0042] The composition according to the present application preferably comprises a polymeric deposition aid. Preferably, the composition comprises an anhydride polymer, especially preferred is a copolymer of maleic anhydride and methyl vinyl ether, wherein the anhydride moiety can be in partially or fully hydrolyzed or alcoholized form. Preferred copolymers include Gantrez® polymers, for example: Gantrez S-95: molecular weight 216,000; free acid; Gantrez S-96: molecular weight 700,000; free acid; Gantrez S-97: molecular weight 1,500,000; free acid; and Gantrez MS-955: molecular weight 1,060,000; calcium / sodium salt.

[0043] Particularly preferred are copolymers of maleic acid and methyl vinyl ether having a molecular weight of 1,000,000 or more, a particularly preferred material being Gantrez S-97.

[0044] The composition according to the present application can comprise a tooth whitening agent. The whitening agent preferably comprises a green and / or blue pigment. Within the scope of the present application, a pigment is generally understood to be a shade / material which is not soluble in the relevant medium at the relevant temperature. This is distinguished from a soluble dye. Within the scope of the present application, "relevant medium" means the liquid medium in which the composition is used, namely human saliva, at an oral temperature, i.e. at most 37°C, during brushing. As a reasonable approximation, the relevant medium can be understood to be water and the relevant temperature can be understood to be 25°C.

[0045] Preferably, the blue pigment is pigment blue 15, more preferably pigment blue 15:1, 15:2, 15:3, 15:4, 15:5 or 15:6, most preferably 15:1. Preferred pigments are blue pigments, phthalocyanine blue pigments, CI No. 74160, blue covarine.

[0046] A preferred green pigment is phthalocyanine green, preferably phthalocyanine green CI-74260.

[0047] Preferably, the total content of pigments in the composition is from 0.01 to 3% by weight, more preferably from 0.02 to 2% by weight.

[0048] If the composition is a toothpaste, it can be a two-phase paste in which the whitening pigment is present in one phase.

[0049] The composition according to the present application can comprise a water-soluble or slightly water-soluble metal salt source. Preferred are zinc ions, such as zinc chloride, zinc acetate, zinc gluconate, zinc sulfate, zinc fluoride, zinc citrate, zinc lactate, zinc oxide, zinc monoglycinate, zinc tartrate, zinc pyrophosphate and zinc maleate; also preferred are stannous ions, such as stannous fluoride and stannous chloride.

[0050] The composition according to the present application can comprise an oral care enzyme system, such as a hydrogen peroxide-generating enzyme system (e.g. oxidoreductase glucose oxidase), amyloglucosidase, dextranase and / or mutanase (optionally in the presence of a compound providing zinc ions and / or an 8-hydroxyquinoline derivative), lactoperoxidase, lactoferrin, lysozyme and mixtures thereof.

[0051] The composition of the present application can comprise fluoride sources such as sodium fluoride, stannous fluoride, sodium monofluorophosphate, ammonium zinc fluoride, ammonium tin fluoride, calcium fluoride, ammonium cobalt fluoride and mixtures thereof; The composition according to the present application further comprises other ingredients common in the art, such as: Antibacterial agents such as chlorhexidine, sanguinarine extract, metronidazole, quaternary ammonium compounds such as cetylpyridinium chloride; cetylpyridinium chloride clay complex; bisguanide compounds such as chlorhexidine digluconate, hexetidine, octenidine, alexidine; and halogenated bisphenolic compounds such as 2,2'-methylenebis-(4-chloro-6-bromophenol); Anti-inflammatory agents such as ibuprofen, flurbiprofen, aspirin, indomethacin and the like; Anticaries agents such as sodium fluoride, stannous fluoride, amine fluoride, sodium monofluorophosphate, sodium trimetaphosphate and casein; Plaque buffering agents such as urea, calcium lactate, glycerylphosphochloride and strontium polyacrylate; Vitamins such as Vitamins A, C and E; Plant extracts; Antioxidants of plant origin such as flavonoids, catechins, polyphenols, tannins and mixtures thereof; Desensitizing agents such as potassium citrate, potassium chloride, potassium tartrate, potassium bicarbonate, potassium oxalate, potassium nitrate and strontium salts; Anticalculus agents such as alkali metal pyrophosphates, hypophosphite-containing polymers, organic phosphonates and citrate phosphates and the like; Biological molecules such as bacteriocins, antibodies, enzymes and the like; Flavorants such as peppermint oil and spearmint oil; Proteinaceous substances such as collagen; Preservatives; Shielding agents; Hyaluronic acid; Amino acids such as arginine; Colorants; pH adjusting agents; Sweeteners; Pharmaceutically acceptable carriers such as starch, sucrose, water or water / alcohol systems and the like; Surfactants such as anionic surfactants, non-ionic surfactants, cationic surfactants and zwitterionic or amphoteric surfactants; Humectants such as glycerol, sorbitol, propylene glycol, xylitol, lactitol and the like; binders and thickeners such as sodium carboxymethylcellulose, hydroxyethylcellulose (Natrosol®), xanthan gum, acacia gum, and the like, as well as synthetic polymers such as polyacrylates and carboxyvinyl polymers such as Carbopol®; Polymeric compounds that can enhance the delivery of active ingredients such as antibacterial agents can also be added; buffers and salts for buffering the pH and ionic strength of the oral care composition; and Other optional ingredients that can be included are, for example, bleaching agents such as peroxide compounds such as potassium peroxodisulphate; foaming systems such as sodium bicarbonate / citric acid systems; colour change systems; and the like.

[0052] Method As described above, the method of manufacturing the non-aqueous composition comprises the following sequential steps: i) heating a mixture of organic polyol and structurant to a temperature of 60°C or higher, ii) adding the abrasive and other non-flavour ingredients to the mixture, iii) cooling the resulting mixture from a temperature above 60°C at a cooling rate of 1 °C / minute or higher using an external heat exchanger to form a paste or gel.

[0053] Preferably the method is carried out in a vacuum. The vacuum can be achieved by any suitable method, preferably using a standard rotary vane vacuum pump capable of maintaining a vacuum of at least -800 mbar (g), preferably -950 mbar (g), more preferably -1000 mbar (g).

[0054] A heat exchanger is used to change the temperature of a fluid product by providing a flow path such that the product and a heat exchange medium fluid are indirectly contacted via a heat transfer interface, thereby exchanging energy between the two streams and causing a change in temperature and / or phase change to occur.

[0055] The heat exchanger is preferably a scraped-surface surface heat exchanger or a pin heat exchanger, more preferably a scraped-surface surface heat exchanger. The heat exchange medium is preferably water, more preferably a solution of ethylene glycol and water.

[0056] The cooling rate can be achieved by one or more heat exchangers by passing the high temperature product through the heat exchanger(s) once, thereby cooling it to the specified process end temperature in a single pass, or preferably by recirculating the product through the heat exchanger(s) more than once until it reaches the specified process end temperature. More preferably, the mixture is circulated through the heat exchanger 2 to 5 times. The optimum heat exchanger configuration depends on the process requirements, which include, without limitation, the starting and end temperatures of the heat transfer process, the thermal fluid properties of the product and heat exchange medium, and the heat transfer performance parameters of the heat exchanger and mixer.

[0057] Most preferably, a scraped surface heat exchanger is employed to achieve the increased cooling rate. This type of heat exchanger incorporates product zones in a concentric, alternating arrangement around one or more heat exchange medium zones (i.e. jackets). The product zones contain rotating scrapers which increase heat transfer efficiency by promoting turbulence and breaking down the formation of stagnant product layers at the heat transfer interface. One suitable heat exchanger is Perfinox PERFITHERM 05 (PFTM05, supplied by Perfinox).

[0058] The product at the heat transfer interface (i.e. the jacket wall) is cooled by heat transfer to a cooling medium circulating within the heat exchanger jacket; and ii) is periodically contacted with multiple rows of high frequency rotating scrapers. Each row of vertically stacked scrapers removes a layer of cooler product from the vessel wall and reintroduces this material into the bulk mass. The choice of heat exchanger configuration determines whether the product is discharged at this stage, or passed to another heat exchanger, or recycled back to the mixer.

[0059] Preferably, the mixture is recycled through the heat exchanger 2 to 5 times, more preferably.

[0060] Preferably, the heat exchanger is located externally to the mixing vessel.

[0061] The frequency of the scraper rotation influences the efficiency of heat transfer as well as the magnitude of shear forces experienced by the product within the heat exchanger. Preferably, the scraper frequency is 10 to 60 rpm, more preferably 25 to 45 rpm, most preferably 30 to 40 rpm.

[0062] Preferably, i) the liquid organic polyol and structurant mixture is heated to a temperature of 65°C or greater.

[0063] Preferably, the cooling rate of the mixture is greater than 2°C / min, more preferably greater than 3°C / min. More preferably, the cooling rate is 5°C / min or less. Particularly preferred is a fast cooling rate of 3°C / min to 5°C / min.

[0064] Preferably, the composition is rapidly cooled to room temperature.

[0065] The residence time of the product within the external heat exchanger determines the temperature change between the inlet and outlet of the apparatus. Preferably, the residence time of the anhydrous product within the heat exchanger is less than 20 minutes, more preferably less than 15 minutes, most preferably less than 10 minutes.

[0066] Preferably, the flavour or flavouring is added at a temperature of 45°C or less. In another embodiment, the flavour or flavouring is added in-line between a series of external heat exchangers.

[0067] The present application is illustrated below by the following non-limiting examples: the process according to the application is indicated by numbers, the comparative examples are indicated by letters.

[0068] Example The following examples were prepared using the following process: The structuring component, such as various forms of carrageenan, different grades of PEG, xanthan gum or combinations thereof, were pre-mixed or alternatively dissolved or dispersed in a portion of the bulk liquid, then added to the mixing vessel from the top along with the remaining bulk liquid. The in-container manufacturing process was carried out under vacuum of at least -800 mbar (g) to minimize air entrainment. The liquid mixture in the vessel was first heated to an elevated temperature of 60 to 80°C and held for 30 to 60 minutes to activate and / or fully swell the structuring component. Next, the temperature could be held or reduced to 50°C, then additional solid active ingredients and powdered abrasives were added sequentially from the top in multiple passes. Proper mixing and shear were provided by the overhead agitator to disperse and suspend them. After all the solid additions and mixing steps were completed, the product was cooled from the elevated temperature.

[0069] For Examples 1, 2 and 3 of the present application, cooling was carried out by passing the product through an external heat exchanger where it was cooled. In all examples, flavorants and spices were added to the vessel and dispersed by short high shear mixing only when the vessel temperature was below a maximum temperature of 45°C. Efficient heat transfer between the product and the cooling medium was achieved by allowing the flow from the vessel into the heat exchanger, resulting in a rapid drop in product temperature.

[0070] Examples 1, 2 and 3 involved a configuration where the product was recirculated through the heat exchanger multiple times until it reached the desired product fill temperature of 30°C, achieving a cooling rate of 3.10 to 3.48°C / min.

[0071] For Comparative Examples A, B and C, cooling was carried out by circulating cold water through a jacket surrounding the vessel. Flavorants and spices were then added by way of a final overhead addition, then the product was further cooled to the desired fill temperature. This resulted in a slower cooling rate of 0.40 to 0.81°C / min.

[0072] After each batch was prepared, an initial viscosity measurement was taken using a Brookfield DV-I viscometer equipped with a T-bar spindle size E at 5 rpm for 60 seconds at 25°C. The same measurement was taken after the product was stored for one month at 25°C.

[0073] The examples show that the compositions according to the present application have a higher initial viscosity and a higher viscosity after storage.

Claims

1. A method for manufacturing a non-aqueous composition, comprising the following successive steps: i) Heat the mixture of liquid organic polyol and structuring agent in a container to 60°C or higher; ii) Add non-flavored ingredients, including abrasives, to the mixture; iii) Use a heat exchanger to rapidly cool the resulting mixture from a temperature above 60°C at a cooling rate of 1°C / min or higher to form a paste or gel.

2. The method of claim 1, wherein the heat exchanger is located outside the container for heating the mixture of the liquid organic polyol and the structuring agent.

3. The method according to claim 1 or 2, wherein the heat exchanger is a scraped surface heat exchanger or a needle heat exchanger, preferably a surface heat exchanger.

4. The method according to claim 3, wherein the scraper rotation frequency is 10 to 60 rpm, more preferably 25 to 45 rpm, and most preferably 30 to 40 rpm.

5. The method according to any one of the preceding claims, wherein the cooling rate is greater than 2°C / min, more preferably greater than 3°C / min.

6. The method according to any one of the preceding claims, wherein the cooling rate is 5°C / min or lower.

7. The method according to any one of the preceding claims, wherein i) the liquid organic polyol and structuring agent mixture is heated to a temperature of 70°C or higher.

8. The method according to any one of the preceding claims, wherein the mixture is recycled through the heat exchanger.

9. The method of claim 8, wherein the mixture is circulated through the heat exchanger 2 to 5 times.

10. The method according to any one of the preceding claims, wherein the method is carried out in a vacuum.

11. The method according to any one of the preceding claims, wherein the flavoring agent is added at a mixing temperature of 45°C or lower.

12. The method according to any one of the preceding claims, wherein the structuring agent comprises carrageenan, solid PEG, xanthan gum, or a mixture thereof, preferably carrageenan.

13. The method according to any one of the preceding claims, wherein the composition is a toothpaste composition.

14. The method according to any one of the preceding claims, wherein the non-aqueous composition further comprises a calcium source and a phosphate source, which, when delivered to the tooth, cause the in-situ formation of hydroxyapatite on the tooth.

15. The method of claim 13, wherein the calcium source comprises calcium silicate, and the phosphate source comprises trisodium phosphate, sodium dihydrogen phosphate, and mixtures thereof.

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