PARTICLE CONTAINING AT LEAST ONE VOLATILE SUBSTANCE, PROCESS FOR ITS PREPARATION, A FOOD OR FEED ADDITIVE CONTAINING THE SAME AND USE

Abstract

A particle containing at least one hydrophobic matrix material and at least one volatile substance, the particle contains 60% to 90% by weight of the at least one matrix material, whereby the at least one matrix material is selected from the group of fats, hydrogenated triglycerides and waxes that are solid or semi-solid at 20 C. and 1 atmosphere, that the particle contains 10% to 40% by weight of the at least one volatile substance, whereby the at least one volatile substance is selected from essential oils and/or plant extracts, that the at least one volatile substance is homogeneously distributed in the at least one matrix material, and that the particle has a sphericity from 0.800 to 0.999, as well as to a process for preparing said particle as well as to a food and/or feed additive containing said particle and optionally at least one further component.

Claims

1. A particle or particles containing at least one hydrophobic matrix material and at least one volatile substance, the improvement wherein a single particle contains 60% to 90% by weight of the at least one matrix material, whereby the at least one hydrophobic matrix material is selected from vegetal triglycerides being palm oil, sunflower oil, corn oil, rapeseed oil, peanut oil or soybean oil, that are solid or semi-solid at 20 C. and 1 atmosphere, the single particle contains 10% to 40% by weight of the at least one volatile substance, whereby the at least one volatile substance is selected from essential oils and/or plant extracts, and the at least one volatile substance has a vapor pressure at 125 C. in the range from 10 mm Hg to 200 mm Hg, and the at least one volatile substance is homogeneously distributed in the at least one matrix hydrophobic material, and the particle has a sphericity from 0.800 to 0.999, whereby the particles maintains flowability.

2. The particle according to claim 1, wherein the essential oils and/or plant extracts both being obtained from a plant selected from the group of oregano, thyme, caraway, marjoram, mint, peppermint, anise, orange, lemon, fennel, star anise, ginger, clove, cinnamon, wintergreen and garlic; or from an ingredient or compound of essential oils or plant extracts-preferably selected from the group of trans-anethole, D-limonene, -terpinene, p-cymene, 2-carene, linalool oxide, isomenthone, camphor, linalool, terpinen-4-ol, 2-isopropyl-1-methoxy-4-methylbenzene, L-menthol, ethylamine, -terpineol, -caryophyllene, D-carvone, methyl salicylate, -caryophyllene, lavandulyl acetate, caryophyllene oxide, eugenol, thymol and carvacrol.

3. The particle according to claim 1, wherein the particle has a sphericity from 0.850 to 0.980.

4. The particle according to claim 1, wherein the particle has a diameter in the range from 50 m to 1000 m.

5. The particle according to claim 1, wherein 1 kg of the particles has a D50 value from 120 m to 280 m.

6. The particle according to claim 1, wherein 1 kg of the particles has a particle-size distribution span from 0.30 to 1.40.

7. The particle according to claim 1, wherein the particle contains 12% to 35% by weight of the at least one volatile substance.

8. The particle according to claim 1, wherein the particle contains 70% by weight of hydrogenated sunflower oil and 30% by weight of a mixture of volatile substances consisting of synthetic carvacrol, caraway oil and oregano oil.

9. A food and/or feed additive containing at least one particle according to claim 1, and at least one further component selected from vitamins, trace elements, proteins, enzymes and microorganisms.

10. A process for preparing particles according to claim 1, comprising the steps of: forming a melt of an at least one matrix material selected from the group of fats, hydrogenated triglycerides and waxes that are solid or semi-solid at 20 C. and 1 atmosphere, forming a liquid preparation of the at least one volatile substance selected from essential oils and/or plant extracts, incorporating the liquid preparation of the at least one volatile substance selected from essential oils and/or plant extracts into the melt and thereby forming a melt mixture, forming discrete particles by finely dispersing the melt mixture, cooling the discrete particles, and maturing the discrete particles for at least 14 days, whereby the particles maintain a consistent level of flowability.

11. The process according to claim 10, wherein the steps of forming, cooling, and maturing the discrete particles are performed using spray cooling techniques.

12. The process according to claim 10, wherein the maturing step is conducted by storing the particles at controlled temperature, pressure and relative humidity, wherein the temperature ranges from 15 C. to 45 C., the pressure ranges from 0.7 atm to 1.3 atm, and the relative humidity ranges from 30% to 80%.

13. The process of using at least one volatile substance as a flowability enhancer for particles, wherein the particles contain at least one hydrophobic matrix material and at least one volatile substance as a flow enhancer, and wherein a single particle contains 60% to 90% by weight of the at least one matrix material, the at least one matrix material is selected from palm oil, sunflower oil, corn oil, rapeseed oil, peanut oil or soybean oil, that are solid or semi-solid at 20 C. and 1 atmosphere, the particle contains 10% to 40% by weight of the at least one volatile substance, the at least one volatile substance is selected from essential oils and/or plant extracts, the at least one volatile substance has a vapor pressure at 125 C. in the range from 10 mm Hg to 200 mm Hg, and the at least one volatile substance is homogeneously distributed in the at least one matrix material, whereby the particles maintain flowability.

Description

DESCRIPTION OF THE DRAWINGS

[0067] For further clarification of all aspects of the invention, the invention is described in the following by means of figures and examples. Therein:

[0068] FIG. 1A shows the effect of varying the amount of essential oil (EO) as volatile substance content in particles consisting of a hydrophobic matrix material and at least one volatile substance, when stored at 25 C.

[0069] FIG. 1B shows the effect of varying the amount of essential oil (EO) as volatile substance content in particles consisting of a hydrophobic matrix material and at least one volatile substance, when stored at 37 C.

[0070] FIG. 2 shows a comparison of particles containing a hydrophobic matrix material and 15.0% by weight of essential oil (EO) as volatile substance and either 0%, 5%, 10% by weight of hydrophobic silica.

[0071] FIG. 3 shows the effect of hydrogenated soybean oil or hydrogenated rapeseed oil as hydrophobic matrix material, when stored at 25 C.

DETAILED DESCRIPTION OF THE INVENTION

Examples

Example 1

[0072] Process to prepare particles containing at least one volatile substance in a laboratory test:

[0073] (i) Forming a melt of a matrix material: [0074] Hydrogenated sunflower oil (HSO; CAS-No: 69002-71-1; ADM Sio; VGBSST; melting point: 33 C.-70 C.) was molten in a stainless steel vessel at a melting temperature of 85 C. 700 g of the HSO were poured into a 2 L glass bottle. The glass bottle containing the HSO was stirred on a magnetic stirrer and the temperature was kept at 85 C. [0075] (ii) Forming a liquid preparation of volatile substances: [0076] 44% by weight synthetic carvacrol (CAS-No: 499-75-2), 47% by weight caraway oil (CAS-No: 8000-42-8) and 9% by weight oregano oil (CAS-No: 862374-92-3) were mixed in a glass bottle at approximately 25 C. to form 300 g of a liquid volatile substance mixture. [0077] (iii) Incorporating the liquid preparation of volatile substances into the melt and thereby forming a melt mixture: [0078] 300 g of the volatile substance mixture of step (ii) were added to the melt in the 2 L glass bottle of step (i), forming a melt mixture of the HSO and the volatile substance mixture. The addition of the volatile substances led to a reduction in the temperature of the melt mixture to approximately 60 C. The final melt contained 70% by weight hydrogenated sunflower oil (CAS-No: 69002-71-1) and 30% by weight volatile substances. [0079] (iv) Forming discrete particles by finely dispersing the melt mixture: [0080] The melt mixture was re-heated to 80 C. and pumped through a hose to a spray connection of a spinning disc (stream of melt mixture: 5.7 L/h). The spinning disc was a horizontally oriented disc with fine grooves on the surface. [0081] The melt mixture flowing over the surface of the rotating spinning disc formed fine droplets when leaving the disc's edges. The rotation of the spinning disc (3275 rpm) forced the melt mixture to leave the disc in form of fine droplets. [0082] The spinning disc was assembled within a prilling tower, which was a cuboid chamber with the following dimensions: Lx WH=9070200 cm, in which the spinning disc was installed. [0083] (v) Cooling the fine dropletsforming discrete particles: [0084] Cooling was achieved by maintaining the temperature in a prilling tower around the spinning disk at a maximum of 30 C., a temperature at which the fine droplets harden automatically. When the particles reached the prilling tower bottom the droplets had hardened and a powder consisting of cooled, discrete particles had formed. [0085] (vi) Maturing the particles: [0086] 150 g of the powder obtained after cooling was filled into sachets made from glue-laminated aluminium compound foil (dimensions of the sachets: WH=15.823.0 cm). Without applying vacuum, the sachets were heat-sealed. The sealed, powder-containing sachets were transferred into an incubator (BD 240 incubator, Binder Inc.) for maturation at 25 C., 1 atm, 40%-60% relative humidity, for two weeks.

[0087] Alternatively to the mixture of volatile substances described in Example 1 the following mixtures of volatile substances can be used:

[0088] (a): 30% by weight orange essential oil; 70% anise essential oil;

[0089] (b): 13% by weight oregano oil; 58% by weight thyme oil; 29% by weight caraway oil;

[0090] (c): 51% by weight peppermint oil; 10% by weight marjoram oil; 16% by weight clove oil; 23% by weight star anise oil;

[0091] (d): 67% by weight mint oil; 2% wintergreen oil; 22% by weight L-carvone; 9% by weight methyl salicylate;

[0092] (e): 100% by weight oregano oil;

[0093] (f): 100% by weight ginger oil;

[0094] (g): 45% by weight cinnamon bark oil; 9% by weight trans-cinnamaldehyde; 18% by weight clove oil; 6% by weight eugenol; 2% by weight -caryophyllene; 20% by weight by orange oil;

[0095] (h): 17% by weight carvacrol; 78% by weight thymol; 5% by weight D-carvone;

[0096] (i): 17% by weight of garlic oil; 80% by weight of fennel oil; 3% by weight trans-anethole;

[0097] (j): 41% by weight peppermint oil; 34% by weight clove oil; 25% by weight thymol; or

[0098] (k): 100% by weight carvacrol.

Example 2

[0099] Determination of Flowability by the Angle of Repose-Method:

[0100] A glass funnel with an outlet diameter of 8 mm was hung 15 cm above the center of a round shaped disc with a known radius (r). Sufficient particles were poured through the glass funnel onto the disc for covering the entire disc surface until no more particles could be piled on the disc and particles started to roll over the disc edge, whereby the particles piled on the disc formed a conical pile. For obtaining the conical pile about 100 g of particles were necessary. The height (h) of the conical pile was measured. Finally, the pitch angle could be calculated as the angle of repose (AoR) by applying the following formula:

[00005]$\tan .Math..Math.=\frac{h}{r}$

[0101] In case a powder sample was determined to have an angle of repose from 20 to 55, the powder was considered flowable and thus to possess flowability. A powder and/or particles were considered to maintain flowability, when the angle of repose of said powder or particles was determined by the angle of repose-method to lie within the range from 20 to 55 at least three months after the start of the preparation process of said powder or particles. In case the angle of repose of a powder or particles was non-determinable by the angle of repose-method as described herein, e.g. due to caking, such a powder and/or particles were not considered flowable.

[0102] A consistent level of flowability as described herein is defined as the range of an angle of repose determined one, two, three and/or four months after production start that overlaps with the range of the angle of repose after maturation as described herein; where the range of an angle of repose is defined to be +/5%, preferred to be +/3% of the angle of repose value.

Example 3

[0103] Preparation of Particles Consisting of Different Amounts of Matrix Material and Volatile Substances, and Determination of Flowabilities Thereof:

[0104] Particles were basically prepared as described in Example 1 using different amounts of HSO as matrix material and of the volatile substance mixture as described in Example 1. A first batch of particles was prepared, where the particles consisted of 92.5% by weight HSO and of 7.5% by weight of a volatile substance mixture as described in Example 1. A second batch of particles was prepared, where the particles consisted of 85% by weight HSO and of 15% of a volatile substance mixture as described in Example 1. A third batch of particles was prepared, where the particles consisted of 70% by weight HSO and of 30% of a volatile substance mixture as described in Example 1. The compositions of the three batches are summarized in Table 1.

TABLE-US-00001 TABLE 1 Composition of particles consisting of different amounts of matrix material, i.e. hydrogenated sunflower oil (HSO) and of volatile substance mixture (VSM). The amounts are shown in percent by weight of the complete particle or the complete melt mixture. Batch HSO VSM # % wt % wt 1 92.5 7.5 2 85.0 15.0 3 70.0 30.0

[0105] After maturation, powders from all three batches were stored for 3.5 months, i.e. until four months after the start of the preparation process. Storage was performed at either 25 C. or 37 C. By applying the angle of repose-method as described in detail in Example 2, the flowability of samples from all three batches was determined repeatedly within a time period from the start of the preparation process until four months thereafter. Flowabilities were determined before maturation, after maturation, one, two, three and four months after the start of the preparation process. The resulting curves are shown in FIGS. 1A and 1B. FIG. 1A shows the effect of different amounts of essential oil (EO) as volatile substance in particles on flowability when stored at 25 C. The particle preparation process was started at time 0. Maturation of the particles was performed for two weeks as described in Example 1. Then, particles were stored for 3.5 months at 25 C.+/3% ranges of determined angles of repose are shown as error bars. As indicated, the angle of repose-curve of particles containing 30.0% by weight EO is shown as solid line, the curve of particles containing 15.0% by weight EO is shown as dashed line, the curve of particles containing 7.5% by weight EO is shown as dotted line. After one month, the formation of aggregates of particles containing 7.5% by weight EO prevented the determination of an angle of repose, whereby this non-determinable (n-d) angle of repose is represented here as a drop on the -axis to n-d. FIG. 1B shows the effect of different amounts of essential oil (EO) as volatile substance in particles on flowability when stored at 37 C. The particle preparation process was started at time 0. Maturation of the particles was performed for two weeks as described in Example 1. Then, particles were stored for 3.5 months at 37 C.+/3% ranges of determined angles of repose are shown as error bars. As indicated, the angle of repose-curve of particles containing 30.0% by weight EO is shown as solid line, the curve of particles containing 15.0% by weight EO is shown as dashed line, the curve of particles containing 7.5% by weight EO is shown as dotted line. After one month, the formation of aggregates of particles containing 7.5% by weight EO prevented the determination of an angle of repose, whereby this non-determinable (n-d) angle of repose is represented here as a drop on the -axis to n-d.

[0106] The determined angles of repose (AoRs) and the associated ranges considering +/3% are summarized in Table 2.

TABLE-US-00002 TABLE 2 After Before 14 days 1 2 3 4 maturation maturation month months months months 25 C.: 7.5% wt VSM 3% 25.8 AoR 26.6 n-d n-d n-d n-d +3% 27.4 25 C.: 15.0% wt VSM 3% 22.5 25.3 25.8 25.7 25.5 25.2 AoR 23.2 26.1 26.6 26.5 26.3 26.0 +3% 23.9 26.9 27.4 27.2 27.1 26.8 25 C.: 30.0% wt VSM 3% 33.2 37.0 37.9 37.9 38.8 37.9 AoR 34.2 38.1 39.1 39.1 40.0 39.1 +3% 35.2 39.2 40.3 40.3 41.2 40.3 37 C.: 7.5% wt VSM 3% 25.8 AoR 26.6 n-d n-d n-d n-d +3% 27.4 37 C.: 15.0% wt VSM 3% 22.4 25.7 26.1 26.1 26.1 25.8 AoR 23.1 26.5 26.9 26.9 26.9 26.6 +3% 23.8 27.3 27.7 27.7 27.7 27.4 37 C.: 30.0% wt VSM 3% 33.2 36.8 38.8 37.9 37.2 38.4 AoR 34.2 37.9 40.0 39.1 38.4 39.6 +3% 35.2 39.0 41.2 40.3 39.6 40.8

[0107] In case of caking, an angle of repose (AoR) was non-determinable (n-d).

[0108] As evident from the FIGS. 1A and 1B as well as from the data presented in Table 2, particles containing 7.5% by weight of the volatile substance mixture did not maintain flowability, whereas particles containing 15% or 30% by weight of the volatile substance mixture did maintain flowability. Moreover, before maturation, particles did not maintain a consistent level of flowability as defined herein, whereas particles containing 15% or 30% by weight of the volatile substance mixture that were subjected to maturation did maintain a consistent level of flowability. The results obtained from storage at 25 C. or at 37 C. were comparable, indicating an independence of the observed phenomena from temperatures at least within that range.

[0109] The conditions during maturation were important to obtain particles that have a consistent level of flowability during subsequent storage at last for 3.5 months. When maturing was performed at temperature lower 15 C. and above 45 C., the particles could not reach the consistent level of flowability or the particles clustered together and formed bigger aggregates or clumps. The same is true when maturing is performed at pressure lower 0.7 atm and above 1.3 atm, as well as at relative humidity lower than 30% and higher than 80%.

Example 4

[0110] Determination of the Effect of Added Silica on the Flowability of Particles Containing at Least One Volatile Substance:

[0111] To compare the particles containing 60% to 90% by weight of hydrogenated sunflower oil (HSO) as matrix material and 10% to 40% by weight of a mixture of volatile substaces (VSM), as described herein, to particles containing a silica, a mixture of volatile substances and a matrix material, three batches of particles were prepared according to the compositions described in Table 3.

[0112] To incorporate the silica, the particle preparation process as outlined in Example 1 was adapted according to the desired compositions as described in Table 3. To obtain particles containing 5.0% by weight of the silica, 50 g of hydrophobic silica (Sipernat D 17; CAS-No: 68611-44-9) was added as texturizer or flow enhancing or anticaking agent to 800 g of molten HSO under stirring on a magnetic stirrer at 85 C., after step (i) Forming a melt of a matrix material. When the silica had dispersed completely, 150 g of volatile substance mixture was added as described in Example 1. To obtain particles containing 10.0% by weight of the silica, 100 g of the hydrophobic silica was added to 750 g of molten HSO, accordingly.

TABLE-US-00003 TABLE 3 Batch HSO VSM Silica # % wt % wt % wt 1 85.0 15.0 0.0 2 80.0 15.0 5.0 3 75.0 15.0 10.0

[0113] After maturation, powders from all three batches were stored for 3.5 months, i.e. until four months after the start of the preparation process. Storage was performed at 25 C.

[0114] By applying the angle of repose-method as described in detail in Example 2, the flowability of samples from all three batches was determined repeatedly within a time period from the start of the preparation process until four months thereafter. Flowabilities were determined before maturation, after maturation, one, two, three and/or four months after the start of the preparation process. The resulting curves are shown in FIG. 2. It shows a comparison of particles containing 15.0% by weight essential oil (EO) and containing either 0%, 5%, 10% by weight of hydrophobic silica. The particle preparation process was started at time 0. Maturation of the particles was performed within the first two weeks. Then, particles were stored for 3.5 months at 25 C.+/3% ranges of determined angles of repose are shown as error bars. As indicated, the angle of repose-curve of particles containing 15.0% by weight EO but no silica is shown as solid line, the curve of particles containing 15.0% by weight EO plus 5% by weight silica is shown as dashed line, the curve of particles containing 15.0% by weight EO plus 10% silica is shown as dotted line. After two months, the particles containing either 5% or 10% by weight of silica formed aggregates, preventing a determination of an angle of repose, whereby this non-determinable (n-d) angle of repose is represented here as a drop on the y-axis to n-d.

[0115] Particles containing 15% by weight of the volatile substance mixture but no silica remained flowable throughout the studied period and maintained flowability as well as a consistent level of flowability after maturation. In contrast, particles containing either 5% or 10% by weight of silica in addition to 15% by weight of the volatile substance mixture were astonishingly found to form aggregates and thus did not remain flowable.

Example 5

[0116] Determination of Particle Properties:

[0117] To further describe particles prepared as described in Example 1, the values for sphericity, diameter, D10, D50, D90 and particle-size distribution span (PDS) were determined.

[0118] The sphericity of the prepared particles was determined with an imaging device for particle size distribution analyses using a Camsizer X2 (Retsch GmbH, Germany) with a X-Jet module for dry dispersion. For the measurement, a dispersion pressure of 55 kPa, a maximum feeding rate of 55% and a nominal area density of 0.7% were selected. As criterion for the end of a measurement, a particle count of 250000 was selected.

[0119] The diameter and the values for D10, D50 and D90 were determined by laser diffraction using a Beckman LS 13320 (Beckman-Coulter GmbH, Austria) with a universal liquid module and propan-2-ol (Carl Roth, Germany) as dispersant. The measurement duration was set to 15 seconds. A pump speed of 40% and an obscuration of 15% were selected. To calculate the particle-size distribution span (PDS), the following formula was used:

[00006]$\mathrm{PDS}=\frac{D.Math..Math.90-D.Math..Math.10}{D.Math..Math.50}$

[0120] where the D90 value is the particle diameter below which 90% of a plurality of particles have a smaller diameter, the D10 value is the particle diameter below which 10% of a plurality of particles have a smaller diameter, and the D50 value is defined as the particle diameter below which 50% of a plurality of particles have a smaller diameter and above which 50% of a plurality of particles have a larger diameter.

[0121] In Table 4, exemplary data from three independent production batches (A, B, C) is shown.

TABLE-US-00004 TABLE 4 D10 D50 D90 Batch Sphericity m m m PDS A 0.972 159 236 310 0.64 B 0.935 155 232 310 0.67 C 0.906 159 237 347 0.79

[0122] The particle-size distribution span (PDS) was calculated as PDS=(D90D10)/D50.

Example 6

[0123] Determination of the Effect of Different Matrix Materials on Flowability:

[0124] Particles were basically prepared as described in Example 1 using either hydrogenated soybean oil or hydrogenated rapeseed oil as matrix material and using the volatile substance mixture as described in Example 1. Flowabilities of the different batches of particles were determined by applying the angle of repose-method as described in Example 2. The resulting curves are shown in FIG. 3. Particles containing either hydrogenated soybean oil or hydrogenated rapeseed oil as hydrophobic matrix material were found to basically show the same flowability behavior as particles containing hydrogenated sunflower oil as hydrophobic matrix material. Essentially identical results were observed when the particles were stored at 37 C. or when the particles consisted of 30% volatile substance mixture, 10% hydrogenated soybean oil or rapeseed oil, plus 60% hydrogenated sunflower oil, or when the particles consisted of 30% volatile substance mixture, 35% hydrogenated soybean oil or rapeseed oil, plus 35% hydrogenated sunflower oil.