Method for staining a lipid matrix blue using Ravenala madagascariensis arils

Abstract

Process for coloring a lipid matrix blue from Ravenala madagascariensis arils. The invention relates mainly to a process for coloring a lipid matrix blue, which is essentially characterized in that it comprises at least the steps of: supplying or preparing a lipid matrix in liquid form; supplying or preparing seed arils of the plant species Ravenala madagascariensis; extracting the blue fat from the arils into the lipid matrix in liquid form, heated to a temperature between 40 and 60°C; and obtaining a blue-colored lipid composition. Depending on the nature of the lipid matrix used, the resulting lipid composition can be used in the cosmetic or food industries.

Description

Title of the invention: Method for staining a lipid matrix blue using arils of Ravenala madagascariensis. Technical field

[0001] The invention falls within the field of the extraction of coloring materials of natural origin.

[0002] The invention relates more particularly to the coloring of lipid compositions used, for example, in the cosmetics or food industries. PRIOR ART AND DRAWBACKS OF PRIOR ART

[0003] In the field of cosmetics, it is known to use natural pigments to provide controlled coloring to various cosmetic materials such as creams, lipsticks, foundations, mascaras or hair dye.

[0004] While the pigments used may be of natural origin, prior art extraction processes for these pigments involve the use of chemical solvents that are harmful to the environment. This is notably the case with patent publication WO2009138697, which describes the extraction of pigment-bearing plant cells from natural plant material in a liquid medium containing a solvent such as acetone.

[0005] Furthermore, in this publication, the extracted colouring material is added in a second step to the cosmetic formulation, which entails the implementation of two different processes, which can result in problems of stability and loss of colour, in addition to the consequent manufacturing costs. OBJECTIVE OF THE INVENTION

[0006] The invention therefore aims to overcome the aforementioned drawbacks by proposing a process for extracting the blue color from a natural plant species free from any chemical solvent and ensuring the stability of the color as well as a simple, reproducible and inexpensive implementation. Description of the invention

[0007] To this end, the invention relates to a method for staining a lipid matrix blue, which is essentially characterized in that it comprises at least the following steps: • supply or preparation of a lipid matrix in liquid state • supply or preparation of seed arils of the plant species Ravenala madagascariensis, and • extraction of the blue fat from the arils in the lipid matrix in a liquid state, heated to a temperature between 40 and 60°C, and • obtaining a lipid composition colored blue.

[0008] According to the invention, the lipid matrix forms both the extraction matrix for the blue color of Ravenala madagascariensis arils and the target lipid composition. Thus, in a single operation, the blue fat is extracted into the lipid composition whose blue coloration is desired.

[0009] The method of the invention may also include the following optional features considered individually or according to all possible technical combinations: • The extraction step is carried out under agitation. • The extraction step is carried out under the effect of ultrasound. • the extraction step is carried out for a duration exceeding 10 minutes. • When the extraction step is performed under the effect of ultrasound, the extraction time is between 10 minutes and one hour • The mass percentage of arils in the lipid matrix is ​​between 5% and 20% • The liquid lipid matrix is ​​prepared from a non-liquid lipid matrix which is brought to a temperature between 40 and 60°C to obtain a liquid lipid matrix. • Prior to the extraction stage, the arils are crushed. • After the extraction step, the colored lipid composition is filtered. • the lipid matrix is ​​chosen from a vegetable oil, vegetable butter, natural wax, vegetable wax and an emulsion. • Prior to the extraction stage, the arils are subjected to a grinding operation and, if necessary, drying.

[0010] The invention also relates to a blue-colored lipid composition obtained by the process as previously described, said composition comprising blue fat from the seed arils of the plant species Ravenala madagascariensis.

[0011] The invention further relates to the use of the blue-colored lipid composition obtained according to the process as previously described for manufacturing a cosmetic or agri-food composition.

[0012] The invention finally relates to a cosmetic or agri-food formulation comprising the blue-colored lipid composition obtained according to the process as previously described. DETAILED DESCRIPTION OF THE INVENTION

[0013] The process of the invention is essentially characterized in that it ensures the manufacture of a blue colored lipid composition from a plant material in a single operation without using solvents.

[0014] According to the process of the invention, the blue color contained in the arils of Ravenala madagascariensis is extracted into a lipid matrix at a controlled temperature, resulting in a blue-colored lipid composition ready for use or for use as an ingredient in a formulation, for example, a cosmetic formulation. According to the invention, the extraction of the blue color is carried out directly into a lipid matrix in a liquid state, forming the target lipid composition. The process also allows the desired intensity of the blue color to be modulated. The process of the invention also makes it possible to obtain a lipid composition with a stable blue color. Finally, the process makes it possible to impart to the lipid composition the biological properties of the arils of Ravenala madagascariensis.

[0015] The plant species of the genus Ravenala madagascariensis is a tropical plant species of the Strelitziaceae family, native to Madagascar. The fruit of Ravenala madagascariensis consists of woody, three-chambered capsules with bright blue arils encapsulating pea-sized oily seeds. The process of the invention makes it possible to extract the blue pigment from the arils. Within the scope of the invention, it was discovered that the blue pigment of the arils is found in fat, thus making its extraction possible in a lipid matrix. The process of the invention therefore consists of extracting the blue fat from the arils of Ravenala madagascariensis.

[0016] The lipid matrix of the process of the invention, which serves as the extraction matrix for the blue fat from the arils and as the target lipid composition, can be selected, without limitation, from oils, butters, waxes, and emulsions. By way of example, the oil can be coconut oil, sweet almond oil, sunflower oil, baobab oil, or any other vegetable oil. By way of example, the butter can be cocoa butter, any other vegetable butter, or butter of animal origin. It is also possible to use any vegetable wax or other natural waxes, for example, beeswax. A mixture of these lipid matrices can also be used.

[0017] According to the invention, the lipid matrix is ​​brought to a liquid state when it is not naturally liquid. Preferably, the non-liquid lipid matrix is ​​brought to a temperature between 40°C and 60°C, which is also, according to an essential feature of the invention, the extraction temperature of the blue fat from the arils in said lipid matrix.

[0018] The arils are supplied or prepared so as to be separated from the seeds. If necessary, a sorting operation to remove impurities is also carried out. Preferably, the arils are ground, for example by a knife mill, taking care not to heat them, which could lead to the formation of a paste and / or a separation of the fat and the blue to be extracted. For this purpose, repeated blows of a maximum of 10 seconds are applied to the arils. After grinding, filaments of 3 to 7 millimeters in length are obtained.

[0019] The liquid lipid matrix and the ground arils are then mixed in a suitable container. The mass percentage of arils in the lipid matrix is ​​preferably greater than 5%, preferably less than 20%, and more advantageously 10%. It has been observed in the context of this invention that a mass percentage of arils below 5% results in a blue color that is too pale, which cannot be compensated for by extending the extraction step or increasing the extraction temperature. Conversely, a mass percentage of arils above 20% results in an excessively high content of saturated fatty acids in the lipid matrix, leading to texture problems, particularly excessive viscosity, in the final colored lipid composition.A mass percentage of arils in the lipid matrix of 10% allows both the final lipid composition to achieve the desired intensity of blue color and prevents excessive transfer of saturated fatty acids into the lipid matrix.

[0020] The extraction of the blue fat from the arils in the lipid matrix is ​​carried out by subjecting the arils to a temperature between 40 and 60°C. To do this, the lipid matrix is ​​heated to a temperature between 40 and 60°C and the extraction is performed directly in the heated lipid matrix. Preferably, the lipid matrix is ​​subjected to continuous agitation throughout the extraction process, for example with a magnetic stirrer or a propeller stirrer, which optimizes the extraction yield and ensures a homogeneous blue color for the lipid composition.

[0021] At temperatures below 40°C, the extraction of blue fat is insufficient to impart the desired shades of blue to the colored lipid composition. Above 60°C, the compounds involved in the biological activities of the arils, for example, polyphenols, are degraded. The optimal extraction temperature is preferably between 40 and 45°C. This preferred temperature range allows for a wide range of coloration depending on the extraction time.

[0022] Under these conditions, the extraction is carried out for at least 24 hours in order to obtain a light blue coloration of the lipid composition. The extraction can be carried out for several days depending on the desired intensity of the blue.

[0023] Advantageously, the extraction is carried out under the effect of ultrasound, for example in a 24 kHz ultrasonic bath. Under these conditions, the extraction time varies from 10 minutes to 1 hour depending on the desired intensity of blue in the lipid composition. If the temperature of the lipid matrix rises too much under the effect of ultrasound, a cooling method, for example an ice bath, is used to keep it within the extraction temperature range of 40 to 60°C.

[0024] After extraction and while still in liquid form, the colored lipid composition is filtered to separate the lipid composition from fine impurities and aril residues. For example, a fabric or stainless steel mesh with a size between 50 and 100 microns is used for this purpose.

[0025] The resulting colored lipid composition is left at room temperature, which, depending on the nature of the starting lipid matrix used, may lead to its solidification. The resulting colored lipid composition can then be preserved and stored for use as an ingredient in the cosmetics, food, or textile industries.

[0026] Example 1: Preparation of a blue-colored lipid composition based on sunflower oil

[0027] The arils of Ravenala madagascariensis are separated from the seeds and impurities are removed. The sorted arils are then ground with a knife mill, taking care not to heat them. Sunflower oil is heated to 45°C. The arils are added to the heated sunflower oil at a mass percentage of 10% arils in sunflower oil. The mixture is maintained at 45°C, agitated, and placed in a 24 kHz ultrasonic bath. Extraction is carried out for 30 minutes. The mixture is then filtered and left at room temperature. This yields a blue-colored sunflower oil.

[0028] Example 2: Preparation of a blue-colored lipid composition based on cocoa butter

[0029] In this example, the procedure is the same as in Example 1, except with regard to the preparation of the lipid matrix. Since the cocoa butter is solid at room temperature, it is first heated to 45°C to obtain a liquid cocoa butter. The arils are then added to the liquid cocoa butter to perform the extraction.

[0030] After solidification at room temperature, a blue-colored cocoa butter is obtained.

[0031] Example 3: Stability tests of the blue color at temperature

[0032]

[0033]

[0034] Blue sunflower oil and blue cocoa butter obtained according to examples 1 and 2 respectively are subjected to color stability tests at temperature. Each sample is subjected to temperatures of 45°C, 65°C, and 90°C for durations of 1 hour, 2 hours, and 3 hours, respectively. After each test, the blue color of the sunflower oil is characterized by measuring the "Lab" color space, also known as CIELAB, which is commonly used to characterize colors. The lightness (L) is derived from the luminance of the sample surface, and the parameters a and b express the color deviation from a gray surface. The tests are carried out in daylight, protected from direct sunlight. For each series of tests, the color space of a control, i.e., the blue sunflower oil from Example 1 at room temperature, is also measured. Tables 1 and 2 below report the results respectively for blue sunflower oil from example 1 and blue cocoa butter from example 2.

[0035] Sample L ab Control 35 -44 -9 HTB* lhat45°C 36 -45 -10 HTB* 2h at 45°C 36 -45 -10 HTB*3hat45°C 37 -46 -10 Control 36 -44 -9 HB* Ih at 65°C 36 -44 -9 HB* 2h at 65°C 36 -44 -9 HTB* 3h at 65°C 37 -45 -9 Control 31 -43 -8 HTB* lhat 90°C 32 -44 -8 HB* 2h at 90°C 32 -44 -8 HB* 3h at 90°C 34 -46 -8

[0036] [Table 1] HTB*: Blue sunflower oil obtained according to example 1 Sample L ab Control 48 -51 39 BCB* lhat45°C 48 -52 38 BCB*2h at 45°C 48 -52 38 BCB*3h at 45°C 48 -52 37 Control 36 -49 32 BCB* Ih at 65°C 37 -50 31 BCB* 2h at 65°C 38 -51 31 BCB* 3h at 65°C 40 -53 31 Control 46 -50 36 BCB* lh at 90°C 46 -51 36 BCB* 2h at 90°C 47 -52 35 [Table 2] BCB*: Blue cocoa butter obtained according to example 2

[0037] It is observed that the color difference, or delta E, that is, the difference in color between each sample tested and the control in the test series, is very small. This shows that the process of the invention makes it possible to produce a colored lipid composition whose color is stable at temperature.

[0038] Example 4: Tests for the stability of the blue color in light

[0039] The blue sunflower oil obtained in Example 1 is subjected to tests of color stability in light.

[0040] The sunflower oil of Example 1 is exposed to daylight, protected from direct sunlight, for 90 days. Measurements of the Lab color space are periodically carried out on the same sample and shown in Table 3 below.

[0041] Number of days L ab 0 68 -40 -9 2 70 -40 -11 4 68 -40 -10 6 60 -40 -10 8 71 -39 -11 10 67 -39 -8 30 68 -40 -10 90 69 -39 -10 [Table 3]

[0042] It is observed that the color difference, or delta E, i.e., the color difference between the measurement taken on the first day and the measurement taken after 90 days, is very small. This shows that the process of the invention makes it possible to produce a colored lipid composition whose color is stable under light.

Claims

Demands

1. A method for coloring a lipid matrix blue, characterized in that it comprises at least the steps of: • supplying or preparing a lipid matrix in liquid form • supplying or preparing seed arils of the plant species Ravenala madagascariensis, and • extracting the blue fat from the arils into the lipid matrix in liquid form brought to a temperature between 40 and 60°C, and • obtaining a blue-colored lipid composition.

2. A method according to the preceding claim, characterized in that the extraction step is carried out under agitation.

3. A method according to claim 1, characterized in that the extraction step is carried out under the effect of ultrasound.

4. A method according to any one of the preceding claims, characterized in that the extraction step is carried out for a period of more than 10 minutes.

5. A method according to any one of the preceding claims, characterized in that the mass percentage of arils in the lipid matrix is ​​between 5% and 20%.

6. A process according to any one of the preceding claims, characterized in that the liquid lipid matrix is ​​prepared from a non-liquid lipid matrix which is brought to a temperature between 40 and 60°C to obtain a liquid lipid matrix.

7. A method according to any one of the preceding claims, characterized in that prior to the extraction step, the arils are crushed.

8. A process according to any one of the preceding claims, characterized in that after the extraction step, the colored lipid composition is filtered.

9. A method according to any one of the preceding claims, characterized in that the lipid matrix is ​​selected from vegetable oil, vegetable butter, natural wax, vegetable wax and an emulsion.

10. Blue coloured lipid composition obtained by the process according to any one of claims 1 to 9, characterized in that it comprises blue fat from the seed arils of the plant species Ravenala madagascariensis.

11. Cosmetic or food formulation comprising the blue-colored lipid composition obtained according to the process of claims 1 to 9.