Production of a wax composition for rapeseed oil-based vegetable candles, vegetable candles made from such a composition and corresponding manufacturing process

Description

Technical field of the invention

[0001] The present invention relates generally to the production of a vegetable wax composition for candles based on rapeseed oil ( Brassica Napus ) of a food-grade type, at least partially hydrogenated. The invention is defined by the attached claims 1-12. Technical background

[0002] Rapeseed oil has the advantage of being produced in Europe and is GMO-free, unlike oils from other sources such as palm or soy. Following a partial hydrogenation process, rapeseed oil yields a vegetable fat with a suitable melting point (typically between 40 and 60°C) for use as a base for scented candles. However, rapeseed oil presents a significant textural problem because it is very rich in stearic acid triglycerides (saturated or unsaturated C18), which generates substantial and expansive crystallization resulting in a cauliflower-like appearance (commonly referred to by the English expression "cauliflower"). "blooming effect" ), as illustrated by the figure 1 below.

[0003] To address this, the applicant developed a vegetable wax composition consisting primarily of at least partially hydrogenated edible rapeseed oil, a small but significant amount of long-chain C18, C20, and C22 fatty alcohols (preferably of rapeseed origin or equivalent), and optionally, monoglycerides or diglycerides (preferably of rapeseed origin or equivalent). US2004250464 describes a candle composition comprising a mixture of solid and liquid partially hydrogenated vegetable oils, and further containing a hardening agent, as well as a colorant, fragrance oils, and / or glitter agents. The composition comprises (by weight): a partially hydrogenated solid vegetable oil (40-65%), a vegetable-derived hardening agent (8-22), and a partially hydrogenated creamy vegetable oil (20-31). Description of the invention

[0004] More particularly, the present invention relates to a vegetable wax composition comprising at least 30% by weight relative to the total weight of the wax composition of a food-grade rapeseed oil that is at least partially hydrogenated, said composition being characterized in that it further comprises: 5 to 50% by weight relative to the total weight of the wax composition of a mixture of fatty alcohols comprising long-chain fatty alcohols in C18, C20 and C22, said mixture of fatty alcohols being obtained by hydrogenation and transesterification of an oil comprising a mixture of fatty acids in C18, C20 and C22, 0 to 10% by weight relative to the total weight of the wax composition of a mixture of monoglycerides and / or diglycerides in C18 and C22, said mixture of monoglycerides and / or diglycerides being obtained by lipochemical transformation and recombination of oils comprising a mixture of fatty acids in C18, and C22, and 0 to 15% by weight relative to the total weight of the wax composition of one or more additives.

[0005] For the purposes of this invention, edible rapeseed oil refers to rapeseed oil of a quality conforming to French Decree No. 78-840 of August 9, 1978, which transposed European Directive 76 / 621 / EC, i.e., rapeseed oil with a maximum erucic acid content of 5%. Edible rapeseed oil can also be described as "low erucic acid rapeseed oil" as described in the Codex Alimentarius CXS 210-1999 (hereinafter referred to as Appendix 4).

[0006] Rapeseed oil that is at least partially hydrogenated is defined as rapeseed oil obtained through a chemical transformation process involving the partial or total hydrogenation of fatty acid unsaturates, resulting in a fat (and therefore solid at room temperature). In this application, the degree of hydrogenation of the rapeseed oil is defined by its melting point and iodine value. The melting point is between 40 and 75°C (for fully hydrogenated rapeseed oil), and in particular between 40 and 60°C when the rapeseed oil is only partially hydrogenated. The iodine value is less than 80 (an iodine value of 0 corresponding to fully hydrogenated rapeseed oil).

[0007] For the purposes of this invention, a mixture of fatty alcohols comprising long-chain fatty alcohols in C18, C20 and C22 means a mixture of fatty alcohols obtained from an oil comprising a mixture of fatty acids in C18, C20 and C22, in particular by hydrogenation and transesterification.

[0008] For the purposes of this invention, a mixture of monoglycerides and / or diglycerides in C18 and C22 is understood to mean a mixture of monoglycerides and / or diglycerides obtained by lipochemical transformation and recombination of oils comprising a mixture of fatty acids in C18 and C22.

[0009] The presence, in the composition of vegetable candle wax according to the invention, of this mixture of fatty alcohols at a rate of 5 to 50% makes it possible to modify the crystallization of the triglycerides present in rapeseed oil.

[0010] The optional presence, in the composition of scented candles, of a mixture of monoglycerides and / or diglycerides at a rate of 0 to 10% allows for an improvement in surface area (as illustrated by the figure 2 (see below), which is then smooth and homogeneous and could be altered by additives such as perfumes.

[0011] Preferably, in the wax composition according to the invention: Food-grade rapeseed oil, at least partially hydrogenated, represents at least 50% by weight relative to the total weight of the wax composition; said mixture of fatty alcohols represents 15 to 40% by weight relative to the total weight of the wax composition; said mixture of monoglycerides and / or diglycerides represents 1 to 5% by weight relative to the total weight of the wax composition.

[0012] Preferably, the mixture of fatty alcohols can be obtained by hydrogenation and transesterification of an oil selected from rapeseed oil rich in erucic acid (usually designated by the acronym HEAR in English). For " High Erucic Acid Rape " or mustard oil, or any other oil that has the same fatty acid profile.

[0013] For the purposes of this invention, rapeseed oil rich in erucic acid means rapeseed oil comprising at least 40% by weight of erucic acid (C22) relative to the total weight.

[0014] Conversely, For the purposes of this invention, rapeseed oil low in erucic acid is defined as rapeseed oil containing less than 10% by weight of erucic acid (C22) relative to the total weight.

[0015] Once rapeseed oils rich in erucic acid are transformed into fatty alcohol, notably by hydrogenation and transesterification processes, a more diverse wax composition is obtained, containing long-chain fatty alcohols (of the C18, C20 and C22 type).

[0016] Preferably, the mixture of monoglycerides and / or diglycerides is obtained by saponification, hydrogenation and esterification of an oil chosen from rapeseed oils rich in erucic acid, rapeseed oils poor in erucic acid, mustard oil, and mixtures thereof.

[0017] Advantageously, the wax composition according to the invention may further comprise one or more additives present at a rate of 1 to 15% by weight relative to the total weight of said composition, said additive(s) being chosen from natural or synthetic liposoluble perfume raw materials, repellent agents, insecticidal agents, biocidal active substances, odor-neutralizing agents, colorants and antioxidant stabilizers.

[0018] In the case where the wax composition is intended for the manufacture of a scented candle, the wax composition according to the invention may advantageously comprise 2 to 12% by weight relative to the total weight of the wax composition of one or more perfume raw materials, whether natural or synthetic.

[0019] Examples of perfume raw materials that can be used in the composition of wax according to the invention include essential oils such as lavender essential oil or any fat-soluble perfume concentrate commonly used in candle wax compositions.

[0020] According to a first advantageous embodiment of the present invention, the wax composition according to the invention may comprise: 60% to 80% by weight relative to the total weight of the rapeseed oil wax composition at least partially hydrogenated, 15% to 30% by weight relative to the total weight of the wax composition of a mixture of stearyl alcohol (C18), arachidyl alcohol (C20) and behenyl alcohol (C22), 1% to 5% by weight relative to the total weight of the glyceryl behenate wax composition (also referred to as glycerol behenate); 1% to 5% by weight relative to the total weight of the glyceryl monostearate wax composition (also referred to as glycerol monostearate); This formula allows the addition of 2 to 12% by weight relative to the total weight of the wax composition of one or more natural or synthetic perfume raw materials.

[0021] According to a second advantageous embodiment of the present invention, the wax composition according to the invention may comprise: 60% to 80% by weight relative to the total weight of the rapeseed oil wax composition at least partially hydrogenated; 15% to 30% by weight relative to the total weight of the wax composition of a mixture of stearyl alcohol (C18), arachidyl alcohol (C20) and behenyl alcohol (C22); 1% to 5% by weight relative to the total weight of the glyceryl dibehenate wax composition; 1% to 5% by weight relative to the total weight of the wax composition of a mixture of glyceryl monosterate and glyceryl disterate; 2% to 12% by weight relative to the total weight of the wax composition of one or more natural or synthetic perfume raw materials.

[0022] According to a third advantageous embodiment of the present invention, the wax composition according to the invention may comprise: 60% to 80% by weight relative to the total weight of the rapeseed oil wax composition at least partially hydrogenated, 15% to 30% by weight relative to the total weight of the wax composition of a mixture of stearyl alcohol (C18), arachidyl alcohol (C20) and behenyl alcohol (C22), 0 to 12% by weight relative to the total weight of the wax composition of one or more natural or synthetic perfume raw materials.

[0023] According to a fourth advantageous embodiment of the present invention, the wax composition according to the invention may comprise: 50% to 70% by weight relative to the total weight of the fully hydrogenated rapeseed oil wax composition, and 20% to 40% by weight relative to the total weight of the wax composition of a mixture of stearyl alcohol (C18), arachidyl alcohol (C20) and behenyl alcohol (C22).

[0024] The present invention also relates to a vegetable candle comprising at least one wick (preferably substantially straight) partially embedded in the wax composition according to the invention.

[0025] For the purposes of this invention, a wick is defined as an element that feeds fuel to the flame by capillary action. The wick may be made of cotton, wood, paper, or fibers, particularly cellulose fibers.

[0026] Candles can be container candles (i.e., the wax composition is poured into a container that supports it) or freestanding candles without a container, which have been poured into molds and are removed from the candle.

[0027] Finally, the present invention also relates to a method for manufacturing a vegetable candle according to the invention, comprising the following steps: A) a melting step of the various constituents of a vegetable wax composition for candles according to the invention, this melting step being carried out by heating to a temperature equal to or greater than the highest melting point of the constituents of said vegetable wax composition (for example, 80°C), said melting step leading to the obtaining of hot wax; B) an optional step of adding one or more additives selected from natural or synthetic perfume raw materials, colorants and stabilizers, to dissolve them in the hot wax obtained in step A); and C) at least one pouring step of said hot wax into a container or mold, the wick(s) being integrated into the candle just before pouring step C), or during pouring step C), or after pouring step C).

[0028] Advantageously, step A) of melting can be carried out by keeping the mixture of the different constituents of the composition under agitation to promote a homogeneous mixture.

[0029] Regarding step B), pouring into containers (for container candles) or molds (for freestanding candles) can be done regardless of the temperature, for example, the temperature at which the different components were mixed during melting in step A, or at a lower temperature if the hot wax has sufficient fluidity for pouring. Depending on the size of the container or mold, one or more additional pours can be made to compensate for the volume loss during solidification (the phenomenon of shrinkage) and to create a flatter surface.

[0030] The present invention can also be implemented by conventional candle manufacturing processes such as the formation of powder or chips and their pressing or extrusion.

[0031] Of course, the different features of the invention mentioned above can be implemented with each other in different combinations when they are not incompatible or mutually exclusive.

[0032] Other advantages and features of the present invention will become apparent from the following description, given by way of non-limiting example and with reference to the accompanying figures and examples: [ Fig. 1 ] : there figure 1 is a photograph showing the appearance of rapeseed vegetable fat (partially hydrogenated rapeseed oil); Fig. 2 ] : there figure 2 is a photograph showing a vegetable candle according to 1 invention in a container. Fig. 3 ] : there figure 3 is a photograph showing three vegetable candles in a container conforming to the prior art and one vegetable candle in a container according to the invention, all based on partially hydrogenated rapeseed oil and whose respective compositions and textures are described in more detail in Example 1 below, illustrating the invention without limiting its scope. Fig. 4 ] : there figure 4 is a photograph showing: 1 vegetable candle in a container according to the prior art (left container) and two vegetable candles in a container according to the invention (middle container and right container) and a self-supporting cube candle according to the present invention, all based on fully hydrogenated rapeseed oil.

[0033] THE figures 1 and 2 are described in the preceding descriptive section, while the figures 3 and 4 are described in examples 1 and 2 respectively. EXAMPLE

[0034] The nature of the products used for the manufacture of vegetable candles according to the prior art and according to the invention, the reactor and the process implemented, as well as the characterization processes are detailed below: Products, raw materials : Partially hydrogenated rapeseed oil (hereinafter referred to by the acronym HCPH), fully hydrogenated rapeseed oil C18 fatty alcohol, C20 fatty alcohol, C22 fatty alcohol. Spark plug characterization testsVisual observation, determination of the melting point: a capillary tube containing the wax to be analyzed (approximately 1 mg) is placed in a melting point measuring apparatus equipped with a heating block. The analysis start point is set 5°C below the estimated melting point, and the apparatus is adjusted so that the heating block temperature increases by 1°C per minute. The measured melting point is recorded when the entire material becomes liquid and loses its opacity. Penetration (NF T60-123): this standard describes a test for assessing the hardness of waxes by determining their penetrability using a standardized needle under standardized conditions. The measurement was taken at 23°C and expresses, in tenths of a millimeter, the depth to which a standardized needle penetrates the test sample. EXAMPLES EXAMPLE 1

[0035] A vegetable candle was produced in accordance with the process according to the invention described above from a candle wax composition comprising 75% by weight of a food-grade rapeseed oil at least partially hydrogenated and 25% by weight relative to the total weight of the wax composition of a mixture of fatty alcohols comprising long-chain fatty alcohols in C18, C20 and C22 (see candle 4 in Table 1).

[0036] For comparative purposes, 3 vegetable candles were produced according to the process of the invention using only food-grade rapeseed oil that was at least partially hydrogenated (candle 1), and using a candle wax composition comprising 75% by weight of food-grade rapeseed oil that was at least partially hydrogenated and 25% by weight relative to the total weight of the wax composition of a single C18 fatty alcohol (candle 2) or a C22 fatty alcohol (candle 3).

[0037] The test results are summarized in Table 1 below, next to each of the wax compositions tested, and in addition to the figure 3 .

[0038] These tests show that the wax texture is most refined when obtained with a ternary mixture of alcohol added to partially hydrogenated oil. Furthermore, this mixture has less impact on the final melting point and penetration, which remains close to the base, unlike when C22 alcohol is used alone. figure 3 shows that the most refined texture, the subject of our request, is indeed obtained with a ternary mixture of alcohol added to partially hydrogenated oil (candle 4). Table 1 Composition of wax Appearance Melting point (capillary tube) Penetration (NF T60-123) HCPH 100% very noticeable cauliflower effect 52°C 44 dmm HCPH: 75% Presence of a 54°C 25 dmm C18 Alcohol: 25% unsightly cracking and detachment HCPH: 75% Presence of traces 60°C 15 dmm C22 Alcohol: 25% unsightly white spots, evidence of slight crystallization HCPH: 75% Smooth structure, 54°C 25 dmm mixture of 3 alcohols C 18+C20+C22 (*): 25% homogeneous and without white streaks (*) : The distribution of each fatty alcohol is based on the typical distribution of rapeseed oils with a high erucic acid content (HEAR oil) or mustard oils, i.e., C18: 42% / C20 :10% / C22: 45% (with traces of alcohol)<C18 et > C22) EXAMPLE 2

[0039] For comparative purposes, 3 vegetable candles in a container made from fully hydrogenated rapeseed oil were produced, as well as a self-supporting candle; left container: 100% fully hydrogenated rapeseed oil (food grade) (according to the prior art); middle container: 75% fully hydrogenated rapeseed oil (food grade) and 25% of a C18-C20-C22 fatty alcohol mixture (according to the present invention); right container: 67% fully hydrogenated rapeseed oil (food grade) and 33% of a C18-C20-C22 fatty alcohol mixture (according to the present invention); self-supporting cube candle of composition: 67% fully hydrogenated rapeseed oil (food grade) and 33% of a C18-C20-C22 fatty alcohol mixture (according to the present invention).

[0040] There figure 4shows that the significant cauliflower effect of the left container (in accordance with the prior art) is corrected and smoothed in the other tests according to the present invention.

Claims

1. Wax composition for vegetable candles comprising at least 30% by weight, relative to the total weight of the wax composition, of at least partially hydrogenated edible rapeseed oil, said composition being characterized in that it further comprises: - 5 to 50% by weight, relative to the total weight of the wax composition, of a mixture of fatty alcohols comprising long-chain C18, C20 and C22 fatty alcohols, said mixture of fatty alcohols being obtained from an oil comprising a mixture of C18, C20 and C22 fatty acids, in particular by hydrogenation and transesterification ; - 0 to 10% by weight, relative to the total weight of the wax composition, of a mixture of C18 and C22 monoglycerides and / or diglycerides, said mixture of monoglycerides and / or diglycerides being obtained by lipochemical transformation of an oil comprising a mixture of C18 and C22 fatty acids, and - 0 to 15% by weight, relative to the total weight of the wax composition, of one or more additives.

2. Wax composition according to claim 1, wherein: - the at least partially hydrogenated edible rapeseed oil represents at least 50% by weight, relative to the total weight of the wax composition ; - said mixture of fatty alcohols represents 15 to 40% by weight, relative to the total weight of the wax composition, - said mixture of monoglycerides and / or diglycerides represents 1 to 5% by weight, relative to the total weight of the wax composition.

3. Vegetable candle composition according to claim 1, wherein said mixture of fatty alcohols is obtained by hydrogenation and transesterification of an oil selected from erucic acid-rich rapeseed oil or mustard oil.

4. Wax composition according to any one of claims 1 and 2, wherein said mixture of monoglycerides and / or diglycerides is obtained by saponification, hydrogenation and esterification of an oil selected from erucic acid-rich rapeseed oils, erucic acid-poor rapeseed oils, mustard oil, and mixtures thereof.

5. Wax composition according to any of claims 1 to 4, wherein one or more additives are present in an amount of 1 to 15% by weight, relative to the total weight of said composition, and are selected from natural or synthetic fat-soluble perfume raw materials, repellents, insecticides, biocidal active substances, deodorants, colourants and antioxidant stabilizers.

6. Wax composition according to claim 5, comprising 2 to 12% by weight, relative to the total weight of the wax composition, of one or more fat-soluble perfume raw materials, whether natural or synthetic.

7. Wax composition according to any of claims 1 to 6, comprising : - 60% to 80% by weight, relative to the total weight of the vegetable candle composition, of at least partially hydrogenated rapeseed oil, - 15% to 30% by weight, relative to the total weight of the wax composition, of a mixture of stearyl alcohol (C18), arachidyl alcohol (C20) and behenyl alcohol (C22), - 1% to 5% by weight, relative to the total weight of the vegetable candle composition, of glyceryl behenate ; - 1% to 5% by weight, relative to the total weight of the vegetable candle composition, of glyceryl monostearate ; - 2 to 12% by weight, relative to the total weight of the vegetable candle composition, of one or more natural or synthetic perfume raw materials.

8. Wax composition according to any of claims 1 to 6, comprising : - 60% to 80% by weight, relative to the total weight of the wax composition, of at least partially hydrogenated rapeseed oil, - 15% to 30% by weight, relative to the total weight of the wax composition, of a mixture of stearyl alcohol (C18), arachidyl alcohol (C20) and behenyl alcohol (C22), 1% to 5% by weight, relative to the total weight of the wax composition, of glyceryl dibehenate ; - 1% to 5% by weight, relative to the total weight of the wax composition, of a mixture of glyceryl monostearate and glyceryl distearate ; - 2 to 12% by weight, relative to the total weight of the wax composition, of one or more natural or synthetic perfume raw materials.

9. Wax composition according to any of claims 1 to 6, comprising : - 60% to 80% by weight, relative to the total weight of the wax composition, of at least partially hydrogenated rapeseed oil, - 15% to 30% by weight, relative to the total weight of the wax composition, of a mixture of stearyl alcohol (C18), arachidyl alcohol (C20) and behenyl alcohol (C22), - 0 to 12% by weight, relative to the total weight of the wax composition, of one or more natural or synthetic wax composition raw materials.

10. Wax composition according to any one of claims 1 to 6, comprising - 50% to 70% by weight, relative to the total weight of the wax composition, of fully hydrogenated rapeseed oil, and - 20% to 40% by weight, relative to the total weight of the wax composition, of a mixture of stearyl alcohol (C18), arachidyl alcohol (C20) and behenyl alcohol (C22).

11. Vegetable candle comprising at least one wick partially embedded in the wax composition as defined in any of claims 1 to 10.

12. Method for manufacturing a vegetable candle as defined in claim 11, comprising the following steps: - A) a step of melting the various components of a wax composition as defined in any of the preceding claims, said melting step being carried out by heating to a temperature equal to or higher than the highest melting point of said components of said wax composition, said melting step leading to the obtention of a hot wax ; - B) an optional step of adding one or more additives chosen from natural or synthetic perfume raw materials, colourants and stabilizers ; - C) at least one step of pouring said hot wax into a container or into a mould, the wick(s) being incorporated into the candle just before step C) of pouring, or during step C) of pouring, or after step C) of pouring.