JPH01281140A - Micro-encapsulated ascorbic acid and its manufacture - Google Patents

Abstract

PURPOSE:To permit the uniform coating on the surfaces of particles with wax, by coating with wax the surfaces of the particles of ascorbic acid having a diameter of 1-500mum or by micro-encapsulating the particles by permeating the wax thereinto. CONSTITUTION:A microcapsulated ascorbic acid is produced by immersing the particles of ascorbic acid having a diameter of 1-500mum immersed in a solution of wax dissolved with an organic solvent and thereafter removing the solvent from the particles of ascorbic acid. In another method, the particle may be pelletized after adding an additive substance to the particles of ascorbic acid having a diameter of 1-500mum and mixing the same. After the resulting pelletized particles of ascorbic acid is immersed in a solution of wax dissolved with an organic solvent, the microcapsulated ascorbic acid is produced by removing the solvent therefrom.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to microencapsulated ascorbic acid formed by coating the surface of ascorbic acid particles with wax, and a method for producing the same, which stabilizes ascorbic acid,
It has the function of preventing and controlling elution in water, and is particularly suitable for use as an additive for fish aquaculture.

In addition, ascorbic acid (L-Ascorbic ACl
d)C.

H606 is the same substance as vitamin C and is a white or yellowish white crystal or crystalline powder.

In addition, ascorbic acid particles herein refer to those containing ascorbic acid metal salts such as sodium ascorbate and calcium ascorbate, and ascorbic acid-containing particles in addition to ascorbic acid. In addition to spherical shapes, the shapes of these particles are acicular, plate-like, etc. Therefore, when we say particle size in this specification, we mean the particle size for spherical objects, and the long sleeve length for needle-like objects or plate-like objects. shall be said.

[Conor's technology] Conventionally, as a method for producing microcapsules, the method described in Kagaku Kogaku Vol. 46, No. 10 (1982), pp. 547-551, "Surface improvement technology and effectiveness of fine powder by encapsulation method", especially As described on page 548, there are said to be 14 types including interfacial polymerization method and submerged drying method.

As described in the above-mentioned literature, these microcapsules are used in all industrial fields such as food, medicine, agriculture, feed, fragrances, enzymes, and activated carbon. And the above 1
Among the four types of microcapsule manufacturing methods, the melt dispersion cooling method and the spray cooler method are known as representative methods for attaching waxes to particles.

[Problems to be Solved by the Invention] However, ascorbic acid crystals are needle-shaped or plate-shaped, and this shape does not change even when crushed.

Therefore, microencapsulation of these materials has conventionally been considered difficult. Furthermore, the conventional methods described above have disadvantages, such as high quality temperature of the core particles, which causes thermal deterioration, and a large amount of wax used as a coating.Furthermore, the melt dispersion cooling method Since the wax crystals used as the film tend to be large, the film tends to be non-uniform, and therefore microencapsulation tends to be incomplete. In addition, the spray cooler method has drawbacks such as the need to crush the core material to approximately 1710 mm in diameter after microcapsulation in order to prevent the core material from popping out or protruding during atomization. There is.

[Means for Solving the Problems] In view of the above-mentioned problems, the inventors of the present invention have made extensive studies and have arrived at the present invention.

That is, the present invention provides microencapsulated ascorbic acid (first invention), which is obtained by coating the surface of ascorbic acid particles with a particle size of 1 to 500 pm with a wax or allowing the wax to penetrate into the inside of the particles.

The present invention also provides a method for producing microencapsulated ascorbic acid (second invention), which comprises immersing ascorbic acid particles in a solution prepared by dissolving waxes in an organic solvent, and then removing the solvent from the ascorbic acid particles. After adding and mixing sub-substances to ascorbic acid particles, they are subjected to spheroidization treatment, and then the ascorbic acid-containing particles obtained by the spheroidization treatment are immersed in a solution in which waxes are dissolved in an organic solvent. A method for producing microencapsulated ascorbic acid (third invention) comprising removing the solvent from particles, and immersing the ascorbic acid particles in a solution of waxes dissolved in an organic solvent, and then removing the solvent from the ascorbic acid particles. Obtain even more microencapsulated ascorbic acid particles by

Next, waxes are dissolved in an organic solvent that is soluble in the waxes but not in the film of the microencapsulated ascorbic acid particles, and the dissolved solution is added to the microencapsulated ascorbic acid particles. The present invention provides a method for producing microencapsulated ascorbic acid (fourth invention), characterized in that two-layer microencapsulated ascorbic acid is obtained by immersing acid particles and then removing the solvent.

The production method of the present invention includes, firstly, a method in which needle-shaped or plate-shaped ascorbic acid particles are microencapsulated as they are;
Second, a method in which the acicular or plate-shaped ascorbic acid particles are mixed with an auxiliary substance, spheroidized, and then microcapsulated; There are three types of methods: forming a film on the capsule to form a two-layer microcapsule.

[Function] Waxes that will become a coating substance are dissolved in an organic solvent, and ascorbic acid particles l that will be a core substance are immersed in the solution for a certain period of time, then taken out, and the ascorbic acid particles l are desorbed using a spray dryer or a vacuum dryer. The particles are washed with a solvent and dried to obtain single-layer microencapsulated ascorbic acid (hereinafter referred to as first-layer particles) 3 having a wax film 2 formed on the surface as shown in FIG.

Next, the wax is soluble in the wax,
Dissolving the film 2 of the first layer particles 3 in an organic solvent that does not dissolve it,
The first layer particles 3 are immersed in the solution for a certain period of time and then taken out, and the first layer particles 3 are dried by removing the solvent using, for example, a spray dryer or a vacuum dryer to form a first layer as shown in FIG. Two-layer microencapsulated ascorbic acid particles 9 of the present invention are obtained in which a second layer 8 of wax is formed on the surface of the particles.

In addition, when removing the solvent using a vacuum dryer, the generated particles become agglomerated by bonding with each other through point contact, so they are crushed one by one using a crusher to form a collection of mononuclear particles. body.

Furthermore, even if microencapsulated ascorbic acid particles are obtained by removing the solvent using a spray dryer or vacuum dryer (including crushing), the coating material of the particles may be crystallized or the coating state may be unstable. If a strong film cannot be obtained for reasons such as uniformity (this state is referred to as "semi-finished microencapsulated ascorbic acid"), the aggregate of the particles may be melted and cooled, for example, as shown in Figure 2. After being dispersed and supplied to @ 4 and brought into contact with hot air 5 momentarily to the extent that the surface of the coating material melts, it is immediately introduced into a cooling zone 6 and rapidly solidified by cold air 7 to make the coating densified and uniform. The product microencapsulated ascorbic acid 10 is obtained.

In addition, in the above, when ascorbic acid is immersed in a solution of waxes, some of the waxes penetrate into the inside of the ascorbic acid particles.

The organic solvent used in the present invention must be one with a low boiling point, such as common ethanol, acetone, chloroform, carbon tetrachloride, benzene, n-hexane, etc., or must avoid solvents that dissolve ascorbic acid particles.

Moreover, when forming the second layer of wax film 8 on the film 2 of the first layer particles, the film l! ! Use something that does not dissolve I8.

As described above, as the core substance in the present invention, ascorbic acid, a metal salt of ascorbic acid such as sodium ascorbate, calcium ascorbate, and fine particles such as ascorbic acid-containing particles are used.

In the present invention, when using the melting cooler 4,
Since the coating 2 of the first layer particles is instantaneously melted by the hot air 5 and then rapidly cooled and re-solidified in the cooling zone 6, the particle size as described above is used. If the particles are too small, they become suspended, and if they are too large, they cannot be uniformly melted.

Waxes in the present invention are "organic substances that are solid or semi-solid at room temperature, melt in a temperature range from around room temperature to around 270° C., and have a low melt viscosity." Further, as the waxes, the above-mentioned organic substances may be used alone or in combination. It is also desirable that the waxes have a crystal structure that allows them to be separated without sticking even when crushed in a crusher.

Preferably used waxes are classified and shown in Table 1.

(Hereafter, margin) Further, specific examples of waxes are listed below.

1. Natural oils and fats and hydrogenated oils: Hydrogenated rapeseed oil, hydrogenated and mustard oil, hydrogenated beef tallow, palm oil 2, Wax: Carnauba wax, beeswax, paraffin wax, Montan wax, Ceresin wax, Candelilla wax, Shellac wax 3, Fatty acids: (C+o or higher) Capric acid, undecanoic acid, lauric acid, tridecylic acid, myristic acid, valmitic acid, stearic acid, elaidic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, octadecenoic acid, vaccenic acid, alkali acid, brassidine Acid, cerotic acid, montanic acid, hexadecenoic acid, eicosenoic acid, pentadecylic acid, heptadecylic acid, heptacanoic acid, melisic acid, rough cellic acid, linoleic acid,
Riluic acid, undecanoic acid, cetoleic acid, arachidonic acid, octadecic acid, oleic acid.

4. Alcohol undecanol, lauryl alcohol, tridecyl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, elaidine alcohol, nonadecyl alcohol, eicosyl alcohol, ceryl alcohol, pentadecyl alcohol, heptadecyl alcohol, mericyl alcohol, latucerol , undecyl alcohol, lylyl alcohol, oleic alcohol, lylunyl alcohol 5, fatty acid glycerin ester: caprin, myristin, valmitin, laurin, stearin, elaidin, brassidine, liluin, lilunin,
Addition of organic water-soluble substances with clear melting points in addition to olein 6 and other cholesterol and lecithin By adding a certain amount of water-soluble substances to the wax, the disintegration time of the second layer wax film 18, which is the final product, is increased. can be controlled. Therefore, it is desirable to add a water-soluble substance in accordance with the required usage time of the microcapsules.

Water-soluble substances that can be added include gelatin, gum arabic, sodium carboxymethyl cellulose (CMC)
, polyvinyl alcohol (PvA), cellulose acetate phthalate (CAP), methyl methacrylic acid-methacrylic acid copolymer (trade name Eudragit L30D-
55) etc. are possible.

Addition of zein, etc. Furthermore, proteins belonging to the prolamin family, such as gliadin (wheat), hordin (barley), and zein (corn), may be mixed with the waxes.

The amount of protein used is 10 ascorbic acid particles as the core material.
It is preferably about 0.5 to 8% by weight relative to 0% by weight.

[Examples] The present invention will be explained in more detail based on Examples, but it will be clear that the present invention is not limited to these Examples.

(Example 1) As a wax, a mixture of 400 g of hardened beef tallow with a melting point of 65°C and 100 g of white beeswax was mixed with 3 f of chloroform solvent.
Dissolve in L and keep this at 30°C.

Next, 1000 g of ascorbic acid crystals (manufactured by Nippon Rossier, long-sleeved, 100 g, m) were immersed in the wax solution and stirred quickly so that the whole was homogeneous.

At this time, wax precipitated on the surface of the particles 1, and the whole particles formed a lump-like agglomeration, which was loosened and kept at 30°C.

Next, the slurry containing the wax-coated particles is desolvated by spray drying with a spray dryer at an inlet temperature of about 70°C and an outlet temperature of about 50°C to form mononuclear single-layer microcapsules with a temperature of 30°C. Ascorbic acid was obtained. The particle structure of this more microencapsulated ascorbic acid is shown in the scanning electron micrograph of FIG.

(Example 2) As a wax, hardened beef tallow 500"ζ having a melting point of 65°C is dissolved in 3 volumes of chloroform solvent and kept at 30°C.

Next, a solution was prepared by dissolving 500 g of ascorbic acid crystals (manufactured by Nippon Rossier) in 500 g of distilled water, 3501 g of 20% (W/V) caustic soda was added to this solution, and 500 g of dextrin was added to the above solution while stirring. The obtained viscous solution was spray-dried using a spray dryer to obtain spherical ascorbic acid-containing particles.

1,000 g of the ascorbic acid-containing particles of item L were immersed in the above wax solution, quickly stirred so that the whole was uniform, and kept warm at 30°C in the same manner as in Example 1.

The slurry containing the wax-coated particles was then desolvated by spray drying at an inlet temperature of 70°C and an outlet temperature of about 559°C, and the product was heated to 30°C to form a single-layer microencapsulated ascorbic acid-containing core. Particles were obtained. The particle structure of this single-layer microencapsulated ascorbic acid is shown in the scanning electron micrograph of FIG.

(Example 3) As a wax, 30 g of white Sarashimiro was dissolved in 100 ml of chloroform solvent and kept at 30'C.

Next, 100 g of ascorbic acid crystals (manufactured by Nippon Rossier,
A long sleeve (approximately 150 gm) was immersed in the wax solution, stirred quickly to make it uniform throughout, and kept warm at 30°C in the same manner as in Example 1.

Next, the slurry containing particles coated with waxes was subjected to solvent removal treatment at 60 Torr for 1 hour and then at 5 Torr.
rr or less, vacuum drying was performed for 48 hours, and then crushed to produce microencapsulated ascorbic acid.

(Example 4) As a wax, hardened beef tallow with a melting point of 65°C 119.7
A mixture of 8 g of 30 g and 20.5 g of cowna wax was added to 3.5 g of chloroform solvent.
Dissolve and keep warm at 30'C.

Next, 342 g of ascorbic acid calcium salt (manufactured by Nippon Rossier, long axis approximately 20 pm) was immersed in the wax solution, stirred quickly so that the whole was uniform, and heated at 30°C in the same manner as in Example 1. I kept it warm.

The slurry containing the wax-coated particles is then
Spray drying was carried out using a spray dryer under the same conditions as in Example 1 to obtain a semi-finished product of more microencapsulated calcium ascorbate.

Next, the semi-finished product further microencapsulated calcium ascorbate was supplied to the melting cooler 4 and heated to a temperature of 20''C.
Instantly melt the first layer of wax film 2 with hot air 5,
Next, the mixture was rapidly cooled and solidified in a cooling zone (exhaust temperature: 58°C) into which cold air at 18°C was blown to obtain further microencapsulated ascorbic acid.

As a wax, 12.5g of valmitic acid is 90% (
V/V)! /-JL, solvent 250! lfL and kept warm at 30°C, 250 g of the above microencapsulated calcium ascorbate was immersed in this solution and stirred, and the slurry containing the wax-coated particles was dried in a vacuum dryer. Vacuum drying was carried out under the same conditions as in Example 3, followed by crushing to obtain semi-finished two-layer microencapsulated calcium ascorbate.

Next, the semi-finished two-layer microencapsulated calcium ascorbate was supplied to the melting cooler 4 at a temperature of 220"C.
The second layer film 8 is melted instantaneously with hot air 5 of
Cooling zone where cold air of C is blown (exhaust temperature 55
℃) to obtain two-layer microencapsulated calcium ascorbate. The particle structure of this two-layer microencapsulated ascorbic acid is shown in the scanning electron micrograph of FIG.

[Effects of the Invention] As described above, according to the microencapsulated ascorbic acid and the manufacturing method thereof of the present invention, (1) the product temperature is not raised in the overall manufacturing process, so that the core substance is not thermally denatured; For all particle sizes from small to large,
The surface can be uniformly coated with wax.

(2) Capsule strength can be controlled by adjusting the blending amount of the coating material, the presence or absence of surface melting treatment, two-layer microencapsulation, selection of the coating material, etc.

(3) Even if the amount of the coating material is small, it is possible to create a good coating with high hydrophobicity, and the amount of wax used can be kept to a small amount.

(4) It is possible to create a film with high density and uniformity.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the double-layer microencapsulated ascorbic acid particles of the present invention, and FIG. 2 is an embodiment of the melt cooling machine used in the production method of the present invention. The main figure, FIG. 3, is a cross-sectional view of the double-layer microencapsulated ascorbic acid particles of the present invention. Figures 4 to 6 are scanning electron micrographs showing the particle structure of microencapsulated ascorbic acid obtained in the present invention. DESCRIPTION OF SYMBOLS 1... Ascorbic acid particles, 2... Second layer film of waxes, 3... Single-layer microencapsulated ascorbic acid particles, 4... Melting cooler, 5... Hot air, 6-
- Cooling zone, 7 - Cold air, 8 - Second layer of wax film, 9 - Two-layer microencapsulated ascorbic acid particles, 10 - Microencapsulated ascorbic acid.

Claims (4)

[Claims] (1) Microencapsulated ascorbic acid obtained by coating the surface of ascorbic acid particles with a particle size of 1 to 500 μm or allowing wax to penetrate into the inside of the particles. (2) A method for producing microencapsulated ascorbic acid, which comprises immersing ascorbic acid particles in a solution prepared by dissolving waxes in an organic solvent, and then removing the solvent from the ascorbic acid particles. (3) After adding and mixing an auxiliary substance to ascorbic acid particles, spheroidizing the particles, then immersing the ascorbic acid-containing particles obtained by the spheroidizing process in a solution of waxes dissolved in an organic solvent, A method for producing microencapsulated ascorbic acid, which comprises removing the solvent from the ascorbic acid particles. (4) After immersing ascorbic acid particles in a solution prepared by dissolving waxes in an organic solvent, the ascorbic acid particles are desolvated to obtain further microencapsulated ascorbic acid particles, and then the waxes are dissolved in the organic solvent. The microencapsulated ascorbic acid particles are dissolved in an organic solvent that is soluble in waxes and insoluble in the film of the microencapsulated ascorbic acid particles, and then the microencapsulated ascorbic acid particles are immersed in the solution and then desorbed. A method for producing microencapsulated ascorbic acid, which comprises obtaining bilayer microencapsulated ascorbic acid by solvent treatment.