SMOKING DEVICE COMPRISING AT LEAST ONE BREAKABLE FLAVOURING CAPSULE

Abstract

A smoking device including a tubular element containing tobacco and a filtering element connected to an end of the tubular element. The filtering element includes at least one breakable flavouring capsule which includes at least one core having at least one lipophilic substance and at least one flavouring agent dispersed or dissolved in the lipophilic substance; at least one breakable coating which coats the core and which has at least one chitosan having a weight average molecular weight (Mw) between 25 kDa and 400 kDa. Preferably, the breakable coating further includes at least one polyhydroxyalkanoate (PHA). The frangible coating that coats the core is able to preserve its hardness, and therefore its breakability, during use by the smoker, i.e. in the presence of humidity and heat that develop from the combustion of tobacco.

Claims

1. A smoking device comprising a tubular element containing tobacco and a filtering element connected to an end of said tubular element, wherein said filtering element includes at least one breakable flavouring capsule which comprises: at least one core comprising at least one lipophilic substance and at least one flavouring agent dispersed or dissolved in said lipophilic substance; and at least one breakable coating which coats said core and which comprises at least one chitosan having a weight average molecular weight (Mw) comprised between 25 kDa and 400 kDa.

2. The device according to claim 1, wherein said at least one chitosan has a weight average molecular weight (Mw) comprised between 50 kDa and 350 kDa.

3. The device according to claim 1, wherein said at least one chitosan has a Brookfield viscosity, measured at 25° C. on an aqueous solution at 1% by weight of acetic acid containing 1% by weight of chitosan, from 20 to 300 cP.

4. The device according to claim 1, wherein said at least one lipophilic substance is selected from the group consisting of: triglycerides, in particular medium-chain C.sub.6-C.sub.12 fatty acid triglycerides, such as caproic, caprylic, capric and lauric acid, or mixtures thereof; vegetable oils, such as olive oil, corn seed oil, sunflower seed oil, peanut oil, soybean oil, coconut oil, almond oil.

5. The device according to claim 1, wherein said at least one flavouring agent is selected from the group consisting of: bergamot oil, eucalyptol oil, mint oil, ethyl methylphenylglycidate (strawberry flavour), or mixtures thereof.

6. The device according to claim 1, wherein the core comprises: from 80% by weight to 99.5% by weight of at least one lipophilic substance, and from 0.5% by weight to 20% by weight of at least one flavouring agent, the percentage by weight being expressed with respect to the overall weight of the core.

7. The device according to claim 1, wherein the breakable coating further comprises at least one polyhydroxyalkanoate (PHA).

8. The device according to claim 7, wherein the breakable coating comprises: from 20% by weight to 80% by weight of at least one chitosan, and from 20% by weight to 80% by weight of at least one PHA, the percentage by weight being expressed with respect to the overall weight of the coating.

9. The device according to claim 1, wherein said at least one flavouring agent is adsorbed on particles of a PHA.

10. The device according to claim 7, wherein the PHA is selected from the group consisting of: poly-hydroxybutyrate (PHB), poly-3-hydroxyvalerate (PHV), poly-3-hydroxyhexanoate (PHH), poly-3-hydroxyoctanoate (PHO), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), poly(3-hydroxybutyrate-co-3-hydroxyesanoate) (PHBH), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxyoctanoate-co-3-hydroxyundecen-10-enoate) (PHOU), poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxyvalerate) (PHBVV), polyhydroxybutyrate-hydroxyvalerate copolymer, or mixtures thereof.

11. The device according to claim 1, wherein said at least one breakable coating has a crushing strength comprised between 2 N and 16 N.

12. A breakable flavouring capsule which comprises: at least one core comprising at least one lipophilic substance and at least one flavouring agent dispersed or dissolved in said lipophilic substance; and at least one breakable coating which coats said core and which comprises at least one chitosan having a weight average molecular weight (Mw) comprised between 25 kDa and 400 kDa.

13. The capsule according to claim 12 and further comprising: at least one core comprising at least one lipophilic substance and at least one flavouring agent dispersed or dissolved in said lipophilic substance; at least one breakable coating which coats said core and which comprises at least one chitosan having a weight average molecular weight (Mw) comprised between 50 kDa and 350 kDa.

14. Use of a capsule according to claim 12, to aromatize the smoke generated in a smoking device.

15. A process for producing a capsule according to claim 12, the process including the following steps: providing a suspension or a solution of at least one flavouring agent in at least one lipophilic substance, providing a solution or an aqueous acid suspension of at least one chitosan, coextruding said suspension or solution of at least one flavouring agent and said solution or acid aqueous suspension of at least one chitosan through a coaxial needle, so as to coat cores of said suspension or solution of at least one flavouring agent with a coating layer of said solution or acid aqueous suspension of at least one chitosan, and solidifying and drying said cores thus coated by obtaining the capsules.

16. The process according to claim 15, wherein the step of solidifying the coated cores is carried out by immersing the capsule as soon as coextruded in a solidification solution.

17. The process according to claim 16, wherein the solidification solution is an aqueous solution of a product selected from the group consisting of: alkali or alkaline-earth metal hydroxides (in particular NaOH or KOH), sodium pentabasic triphosphate, phytic acid, sodium citrate, oxalic acid, or mixtures thereof.

Description

DETAILED DESCRIPTION OF THE DRAWINGS

[0050] FIG. 1 represents, in longitudinal section, a possible embodiment of a smoking device, in particular a cigarette, in accordance with the present disclosure. The smoking device (1) comprises a tubular element (2), substantially cylindrical in shape, which contains tobacco (3). The tobacco (3) is wrapped in a layer of material (4), generally paper, which maintains the shape and dimensional stability of the tubular element (2).

[0051] The tubular element (2) comprises a first free end (5) intended to be lighted by the user, while the opposite end (6) is associated with a filtering element (7). The filtering element (7) is preferably in direct contact with the tobacco (3) contained in the tubular element (2) and axially aligned with the latter. Also the filtering element (7) has a substantially cylindrical shape, and includes a filtering material (8) (generally cellulose acetate fibres impregnated with triacetin) coated with a containment layer (9), generally formed by paper. Inside the filtering material (8) there is at least one capsule (10) in accordance with the present disclosure. The filtering element (7) generally also includes an outer layer (11) formed by substantially impermeable paper, which is intended to come into contact with the user's fingers and which also acts as a connecting element between the tubular element (2) and the filtering element (7).

[0052] The capsule, according to the present disclosure, is preferably obtained by a coextrusion process through

[0053] a coaxial needle.

[0054] More in detail, the capsule according to the present disclosure is preferably prepared by a process which comprises the steps of:

[0055] providing a suspension or a solution of at least one flavouring agent in at least one lipophilic substance;

[0056] providing a solution or an aqueous acid suspension of at least one chitosan;

[0057] coextruding said suspension or solution of at least one flavouring agent and said solution or acid aqueous suspension of at least one chitosan through a coaxial needle, so as to coat cores of said suspension or solution of at least one flavouring agent with a coating layer of said solution or acid aqueous suspension of at least one chitosan;

[0058] solidifying and drying said cores thus coated by obtaining the capsules.

[0059] Coextrusion through coaxial needle is a process known to those skilled in the art. It is a process of synchronous extrusion of two liquids: an external liquid phase, usually hydrophilic, and an internal liquid phase, usually lipophilic. Said process basically includes three steps: formation of a drop, at the tip of the coaxial needle, comprising the two liquid phases arranged coaxially; collection of the drop; solidification of the outermost liquid phase; collection of the capsule thus formed. Preferably, the capsules are produced by means of a device and a process as described in EP 0 513 603.

[0060] Preferably, the step of solidifying the capsule obtained from the coextrusion step through coaxial needle is preferably carried out by immersing the just coextruded capsule into a solidification solution. The solidification solution is preferably an aqueous solution of a product selected from: alkali or alkaline-earth metal hydroxides (in particular NaOH or KOH), sodium pentabasic triphosphate, phytic acid, sodium citrate, oxalic acid, or mixtures thereof. The immersion is generally carried out at room temperature for a time comprised between 10 minutes and 10 hours.

[0061] The step of drying the coextruded and solidified capsule preferably provides for heating for a time comprised between 1 hour and 10 hours at a temperature between 30° C. and 70° C.

[0062] The following examples of embodiment are provided for the sole purpose of illustrating the present disclosure and are not to be understood in a sense limiting the scope of protection defined by the appended claims.

EXAMPLE 1

[0063] An acid aqueous solution (1% w/w acetic acid) of a mixture of two chitosans of different molecular weight, i.e. a median molecular weight chitosan (Mw=about 200 kDa, concentration=3% w/w) and a low molecular weight chitosan (Mw=about 80 kDa, concentration=1% w/w), was prepared.

[0064] The solution was kept at 40° C. and mixed until complete dissolution of the two chitosans.

[0065] A suspension of PHB particles, on which bergamot oil was adsorbed, in a caprylic/capric triglyceride (PHB 10% w/w, bergamot oil 3% w/w) was prepared.

[0066] The solution and the suspension were coextruded through coaxial needle; the drops formed by coextrusion were collected inside a 1M NaOH solution, left in immersion for 3 hours, transferred to a 1% sodium pentabasic triphosphate solution (cross-linking solution) and left in immersion throughout the night. Subsequently the capsules were washed with water and dried at 50° C. for 5 hours.

EXAMPLE 2

[0067] An acid aqueous solution (3% w/w acetic acid) of chitosan (low molecular weight chitosan Mw=about 80 kDa, concentration=5% w/w) was prepared. The solution was kept at 40° C. and mixed until complete dissolution of the chitosan

[0068] A suspension of PHB particles, on which eucalyptol oil was adsorbed, in a caprylic/capric triglyceride (PHB 10% w/w, eucalyptol oil 3% w/w) was prepared.

[0069] The solution and the suspension were coextruded through coaxial needle; the drops formed by coextrusion were collected inside a 1M NaOH solution, left in immersion for 3 hours, transferred to a 1% sodium pentabasic triphosphate solution (cross-linking solution) and left in immersion throughout the night. Subsequently the capsules were washed with water and dried at 50° C. for 5 hours.

EXAMPLE 3

[0070] An acid aqueous solution (1% w/w acetic acid) of chitosan (median molecular weight chitosan Mw=about 200 kDa, concentration=3.5% w/w) was prepared. The solution was kept at 40° C. and mixed until complete dissolution of the chitosan

[0071] A suspension of PHB particles, on which eucalyptol oil was adsorbed, in a caprylic/capric triglyceride (PHB 10% w/w, eucalyptol oil 3% w/w) was prepared.

[0072] The solution and the suspension were coextruded through coaxial needle; the drops formed by coextrusion were collected inside a 1M NaOH solution, left in immersion for 3 hours, transferred to a 1% sodium pentabasic triphosphate solution (cross-linking solution) and left in immersion throughout the night. Subsequently the capsules were washed with water and dried at 50° C. for 5 hours.

EXAMPLE 4

Crushing Test

[0073] The crushing resistance of the capsules of Examples from 1 to 3 was measured using the Zwick Roell's tool “cLine materials testing machine Z010” with specific configuration for crushing tests.

[0074] The measurements were performed by positioning one capsule at a time in the middle of the tool plate, at the punch. The movement speed of the punch has been set at 1 mm/min.

[0075] At the moment of the breakage of each capsule, the maximum crushing force exerted by the punch, needed to overcome the resistance force of the capsule and cause the latter to break, was recorded. This value was measured in Newtons (N). For each type of capsule the test was repeated 20 times and the values reported in Table 1 represent the average value.

[0076] Following the protocol described above, three different tests were performed:

[0077] measurement of the initial crushing strength, i.e. on the capsule as it is;

[0078] measurement of the crushing strength of the capsule after having subjected it, for 5 minutes, to a temperature of 40° C. and a humidity percentage of 90%;

[0079] measurement of the crushing strength of the capsule after having subjected it, for 4 hours, to a temperature of 40° C. and a humidity percentage of 90%.

TABLE-US-00001 TABLE 1 Initial Crushing Crushing crushing strength (N) strength (N) strength (5 min, 40° C., (4 h, 40° C., Sample (N) 90% UR) 90% UR) Capsule (Ex. 1) 8.55 9.95 11.20 Capsule (Ex. 2) 6.77 8.62 8.58 Capsule (Ex. 3) 7.76 9.10 10.23

EXAMPLE 5

[0080] An acid aqueous solution (1% w/w acetic acid) of chitosan (median molecular weight chitosan Mw=about 80 kDa, concentration=1.75% w/w) was prepared. The solution was kept at 40° C. and mixed until complete dissolution of the chitosan PHB in particle form (PHB concentration 3% w/w) was added and the mixture was emulsified.

[0081] A solution of eucalyptol oil in caprylic/capric triglyceride (9% w/w eucalyptol oil) was prepared.

[0082] A coextrusion of the emulsion and the solution was carried out through coaxial needle; the drops formed by coextrusion were collected in a 1M NaOH solution, left in immersion for 30 minutes, transferred to a 1% sodium pentabasic triphosphate solution (cross-linking solution) and left in immersion throughout the night. Subsequently the capsules were washed with water and dried at 50° C. for 5 hours.

EXAMPLE 6

[0083] An acid aqueous solution (3% w/w acetic acid) of chitosan (low molecular weight chitosan Mw=about 80 kDa, concentration=5% w/w) was prepared. The solution was kept at 40° C. and mixed until complete dissolution of the chitosan PHB in particle form (PHB concentration 5% w/w) was added and the mixture was emulsified.

[0084] A solution of eucalyptol oil in caprylic/capric triglyceride (9% w/w eucalyptol oil) was prepared.

[0085] A coextrusion of the emulsion and the solution was carried out through coaxial needle; the drops formed by coextrusion were collected in a 1M NaOH solution, left in immersion for 30 minutes, transferred to a 1% sodium pentabasic triphosphate solution (cross-linking solution) and left in immersion throughout the night. Subsequently the capsules were washed with water and dried at 50° C. for 5 hours.

EXAMPLE 7

[0086] An acid aqueous solution (1.5% w/w acetic acid) of chitosan (median molecular weight chitosan Mw=about 200 kDa, concentration=2.5% w/w) was prepared. The solution was kept at 40° C. and mixed until complete dissolution of the chitosan PHB in particle form (PHB concentration 2.5% w/w) was added and the mixture was emulsified.

[0087] A solution of eucalyptol oil in caprylic/capric triglyceride (9% w/w eucalyptol oil) was prepared.

[0088] A coextrusion of the emulsion and the solution was carried out through coaxial needle; the drops formed by coextrusion were collected in a 1M NaOH solution, left in immersion for 30 minutes, transferred to a 1% sodium pentabasic triphosphate solution (cross-linking solution) and left in immersion throughout the night. Subsequently the capsules were washed with water and dried at 50° C. for 5 hours.

EXAMPLE 8

Crushing Test

[0089] The crushing resistance of the capsules of Examples 5 to 7 was measured as described in Example 4. The results are reported in Table 2.

TABLE-US-00002 TABLE 2 Initial Crushing Crushing crushing strength (N) strength (N) strength (5 min, 40° C., (4 h, 40° C., Sample (N) 90% UR) 90% UR) Capsule (Ex. 5) 5.44 6.83 7.27 Capsule (Ex. 6) 8.05 8.48 9.60 Capsule (Ex. 7) 4.00 7.90 8.05

[0090] From the results reported in Tables 1 and 2 it is evident that the capsules according to the present disclosure possess a breakable coating capable of preserving its hardness, and therefore its breakability, even in the presence of humidity and heat. This is also demonstrated under particularly severe conditions, i.e. after a 4-hour treatment at a temperature of 40° C. and a humidity of 90%.