HOMOGENISED BOTANICAL MATERIAL COMPRISING A BASIC PH MODIFIER

Abstract

A homogenised botanical material is provided, including a particulate plant material, a content of which is greater than or equal to about 60% by weight, on a dry weight basis; an aerosol former; and a basic pH modifier having a solubility in water of less than or equal to about 0.1 g/100 mL water at 20° C. and 1 atm, the basic pH modifier including one or more basic inorganic salts selected from the group consisting of: alkaline earth metal hydrogen carbonates, alkaline earth metal hydroxides, and alkaline earth metal phosphates.

Claims

1.-14. (canceled)

15. A homogenised botanical material, comprising: a particulate plant material, a content of which is greater than or equal to about 60% by weight, on a dry weight basis; an aerosol former; and a basic pH modifier having a solubility in water of less than or equal to about 0.1 g/100 mL water at 20° C. and 1 atm, the basic pH modifier comprising one or more basic inorganic salts selected from the group consisting of: alkaline earth metal hydrogen carbonates, alkaline earth metal hydroxides, and alkaline earth metal phosphates.

16. The homogenised botanical material according to claim 15, wherein the basic pH modifier further comprises one or more basic inorganic salts selected from the group consisting of: magnesium hydrogen carbonate, magnesium hydroxide, magnesium phosphate, and calcium phosphate.

17. The homogenised botanical material according to claim 15, wherein the homogenised botanical material has a pH greater than or equal to about 5.5.

18. The homogenised botanical material according to claim 15, wherein the homogenised botanical material has a pH less than or equal to about 8.0.

19. The homogenised botanical material according to claim 15, wherein the homogenised botanical material has a pH of between about 6.0 and about 7.5.

20. The homogenised botanical material according to claim 15, wherein the homogenised botanical material has an aerosol former content of between about 5% and about 25% by weight on a dry weight basis.

21. The homogenised botanical material according to claim 15, further comprising a lipid having a melting point of between about 50° C. and about 150° C.

22. The homogenised botanical material according to claim 15, wherein the homogenised botanical material is a homogenised tobacco material and the particulate plant material is tobacco.

23. A sheet of homogenised botanical material, comprising a homogenised botanical material according to claim 15.

24. An aerosol-generating rod, comprising a gathered sheet of the homogenised botanical material according to claim 23 circumscribed by a wrapper.

25. An aerosol-generating article for an electrically-operated aerosol-generating system, the aerosol-generating article comprising an aerosol-generating rod according to claim 24.

26. An aerosol-generating article, comprising a combustible heat source and an aerosol-generating rod according to claim 24 disposed downstream of the combustible heat source.

27. A method of making a cast sheet of homogenised botanical material, comprising the steps of: combining particulate plant material, an aerosol former, and a basic pH modifier having a solubility in water of less about 0.1 g/100 mL water at 20° C. and 1 atm to form a slurry, the basic pH modifier comprising one or more basic inorganic salts selected from the group consisting of: alkaline earth metal hydrogen carbonates, alkaline earth metal hydroxides, and alkaline earth metal phosphates; casting the slurry onto a support surface; drying the cast slurry to form the cast sheet of homogenised botanical material, wherein a particulate plant content of the cast sheet of homogenised botanical material is greater than or equal to about 60% by weight on a dry weight basis; and removing the cast sheet of homogenised botanical material from the support surface.

28. The method according to claim 27, further comprising the steps of: gathering the cast sheet of homogenised botanical material transversely relative to a longitudinal axis thereof; circumscribing the gathered cast sheet of homogenised botanical material with a wrapper to form a rod; and severing the rod into a plurality of discrete aerosol-generating rods.

Description

EXAMPLE

[0199] Cast sheets of homogenised tobacco material are prepared having the compositions shown in Table 1, where the values shown are the percentages by weight on a dry weight basis:

TABLE-US-00001 TABLE 1 Sample 1 Sample 2 Sample 3 Component (reference) (comparison) (invention) Tobacco powder 75 73.15 72.83 Glycerol (aerosol former) 20 20 20 Guar gum (binder) 3 3 3 Cellulose fibres 2 2 2 Basic pH modifier 0 1.85 2.17 (calcium (magnesium hydroxide) hydroxide)

[0200] To prepare the cast sheet of homogenised tobacco material of sample 1, the tobacco powder, glycerol, guar gum and cellulose fibres are combined with water to produce an aqueous slurry. The aqueous slurry is cast onto a support surface and then dried to form the cast sheet of homogenised tobacco material of sample 1.

[0201] To prepare the cast sheets of homogenised tobacco material of samples 2 and 3, the tobacco powder, glycerol, guar gum, cellulose fibres and basic pH modifier are combined with water to produce an aqueous slurry. The aqueous slurry is cast onto a support surface and then dried to form the cast sheets of homogenised tobacco material of samples 2 and 3.

[0202] The pH of the aqueous slurries used to form the cast sheets of homogenised tobacco material of samples 1, 2 and 3 measured using a pH electrode.

[0203] The pH of the cast sheets of homogenised tobacco material of samples 1, 2 and 3 is measured by dispersing 5 g of the cast sheet of homogenised tobacco material in 5 g of water and measuring the pH of the dispersion using a pH electrode.

[0204] The pH values obtained are shown in Table 2 below.

[0205] The nicotine content of methanoic extracts of samples of the cast sheets of homogenised tobacco material of samples 1 to 6 is measured using a gas chromatography flame ionization detector (GC-FID).

[0206] The cast sheets of homogenised tobacco material of samples 1, 2 and 3 are gathered and circumscribed by a wrapper to form aerosol-generating rods. Heated aerosol-generating articles for use in an electrically-operated aerosol-generating system are formed comprising aerosol-generating substrates comprising the aerosol-generating rods.

[0207] The nicotine content of aerosols generated by electrically heating the heated aerosol-generating articles to a maximum temperature of 350° C. under Health Canada smoking conditions is determined using GC-FID. The nicotine transfer yields of the heated aerosol-generating articles are calculated from the nicotine content of the aerosols, the nicotine content of the cast sheets of homogenised tobacco material and the quantity of homogenised tobacco material in the aerosol-generating substrate of the heated aerosol-generating articles. The nicotine transfer yield is defined as (amount of nicotine delivered in the aerosol upon heating)/(amount of nicotine in the gathered cast sheet of homogenised tobacco material in the aerosol-generating substrate of the aerosol-generating article before heating). The results are shown in the Table 2 below:

TABLE-US-00002 TABLE 2 Nicotine loss during pH of preparation of Increase of cast sheet of pH of cast sheet of nicotine homogenised aqueous homogenised transfer Sample tobacco material slurry tobacco material* yield* 1 5.30 5.02 — — 2 6.39 7.65 11.1% 15% 3 6.86 6.44 5.7% 17% *relative to sample 1

[0208] As shown in Table 2, inclusion of a basic pH modifier in the cast sheets of homogenised tobacco material of samples 2 and 3 significantly increases the pH of the cast sheets of homogenised tobacco material of samples 2 and 3. As shown in Table 2, inclusion of a basic pH modifier in the cast sheets of homogenised tobacco material of samples 2 and 3 also advantageously significantly increases the nicotine transfer yield of the heated aerosol-generating articles comprising the cast sheets of homogenised tobacco material of samples 2 and 3 compared to the heated aerosol-generating article comprising the cast sheet of homogenised tobacco material of sample 1, which does not include a basic pH modifier.

[0209] However, as shown in Table 2, inclusion of calcium hydroxide, which has a solubility in water of about 0.173 g/100 mL water at 20° C. and 1 atm as the basic pH modifier in the cast sheet of homogenised tobacco material of sample 2 also disadvantageously significantly increases the nicotine loss during preparation of the cast sheet of homogenised tobacco material of sample 2 compared to the cast sheet of homogenised tobacco material of sample 1, which does not include a basic pH modifier.

[0210] By contrast, inclusion of magnesium hydroxide, which has a solubility in water of about 0.00096 g/100 mL water at 20° C. and 1 atm, as the basic pH modifier in the cast sheet of homogenised tobacco material of sample 3 advantageously results in a much smaller increase in the nicotine loss during preparation of the cast sheet of homogenised tobacco material of sample 2 compared to the cast sheet of homogenised tobacco material of sample 1, which does not include a basic pH modifier.

[0211] The specific embodiments described above are intended to illustrate the invention. However, other embodiments may be made without departing from the scope of the invention as defined in the claims and it is to be understood that the specific embodiments described above are not intended to be limiting.