US3729009A

US3729009A - Smoking product with improved flavor and method of making it

Info

Publication number: US3729009A
Application number: US00126967A
Authority: US
Inventors: C Stevens; W Selke
Original assignee: Kimberly Clark Corp
Current assignee: Kimberly Clark Corp
Priority date: 1971-03-22
Filing date: 1971-03-22
Publication date: 1973-04-24
Anticipated expiration: 1990-04-24
Also published as: CA942151A; GB1352663A; AU3888672A; FR2131501A5; CH563730A5; ZA72813B; DE2206859A1

Abstract

A smoking product including a substantial proportion of tobacco stem material and incorporating carbamide and a saturated fatty acid composition having a carbon chain length of 16-18. The carbamide is present in an amount from 1.0 to 3.0 percent and the fatty acid is present in an amount of from 1.0 to 4.0 percent, by weight, of the stem material. The carbamide and fatty acid impart to the stem material, when it burns, some of the more pleasant taste and smell characteristics of burning tobacco leaf. The stem material may be in its natural state, but crushed, or it may be made into a reconstituted sheet or film.

Description

United States Patent 11 1 Stevens et al.

SMOKING PRODUCT WITI-I IMPROVED FLAVOR AND METHOD OF MAKING IT Inventors: Chester U. Stevens; William A.

Selke, both of Stockbridge, Mass.

Assignee: Kimberly-Clark Corporation, Nee

nah, Wis.

Filed: Mar. 22, 1971 Appl. No.: 126,967

US. Cl. ..l3l/17, 131/2, 131/144,

131/140 C Int. Cl. ...A24b 03/14, A24b 15/04, A24b 03/12 Field ofSearch ..13l/17, 140-144 References Cited UNITED STATES PATENTS 9/1971 Briskin et a1. 1 31/2 1/1967 Osborneetal ..131/140C 3,298,378 1/1967 Stevens et a1 ..131 140 c 3,464,422 9/1969 Light et al v ..131/140 c 2,576,021 11/1951 Koree ..131/2 Primary Examiner-Melvin D. Rein Attorney-Breitenfeld & Levine [57] ABSTRACT A smoking product including a substantial proportion of tobacco stem material and incorporating carbamide and a saturated fatty acid composition having a carbon chain length of 16-18. The carbamide is present in an amount from 1.0 to 3.0 percent and the fatty acid is present in an amount of from 1.0 to 4.0 percent, by weight, of the stem material. The carbamide and fatty acid impart to the stem material, when it burns, some of the more pleasant taste and smell characteristics of burning tobacco leaf. The stem material may be in its natural state, but crushed, or it may be made into a reconstituted sheet or film.

7 Claims, No Drawings SMOKING PRODUCT WITH IMPROVED FLAVOR AND METHOD OF MAKING IT This invention relates generally to tobacco, and has rated fatty acids and carbamide are non-toxic and harmless, and are compatible with tobacco and with substances commonly employed in the preparation of articles for smoking. For these reasons they have been particular reference to making products having im- 5 found to be admirably suitable as additives to tobacco proved smoking qualities, and to a method of making and tobacco products. Their employment is practically such products. feasible, and allows tobacco stems to be used in larger The term Smoking produc is intended to in proportions by making up for the natural deficiencies within its scope all known media, such as cigars, of such stems as contributors to smoking values. cigarettes, Smok ng toba co, em, for j ying the Moreover, addition of the fatty acids and carbamide ar m and flavor ofbunling tobacco beneficiates both the main and the side streams of h? desirable flavor and Smell of burning tobacco is smoking tobacco. By main stream" reference is made derived Primarily m the Products of Py y g to the smoke traveling directly into the smokers d r d y h Smooth laminar p r of the leaves of mouth, and by side stream" is meant the smoke the tobacco plant. The midribs of the leaves, commonly emanating directly from the burning tobacco product. but inaccurately referred to in the trade as stems", are A more particular object of the invention is to prodeficient in producing the same effects. Burning stem vide an economical and commercially practical portions produce a flat smoke and contribute only a procedure by means of which the fatty acid and carbah y aromatic touchmide can be advantageously incorporated in tobacco For the sake of simplicity, the smooth portions of the products for the intended purpose. leaves will be referred to hereinafter as leaf" and the The following flow diagram is illustrative of a midribs will be r f rred to as stems. procedure that has been found to be useful and Some tobacco products, notably sheeted tobacco satisfactory:

NATURAL SOLVENT TOBACCO EXTRACT STEMS CONCENTRATION L FIBROUS RESIDUE SATURATED r- FATTY ACID WATER BEA'IER I AND CARBAMIDE Jr SHEETED TOBACCO PRODUCT materials, contain appreciable and sometimes predominant proportions of natural tobacco stems. It is an object of this invention to improve the smoking qualities need not be Composed exclusively of Stems but y of such products. Coordinately, it is an objective of the invention to impart enhanced desirable aroma and flavor to articles for smoking whose composition includes, or may consist essentially of, fragments of natural tobacco stems.

clude leaves or fragments of leaves in any desired proportion. The solvent employed to produce the extract, and leave a fibrous residue, is usually and preferably water but is not necessarily or exclusively aqueous. The

beater employed is part of known papermaking equipment, and the fibrous residue is adequately comminuted so as to be employable like paper pulp in producing a slurry or suspension from which a paperlike web is produced in accordance with conventional papermaking techniques. The extract from the original.

product is first concentrated and may then be treated, if desired, in various ways (not shown) to alter or improve its composition. Finally it is introduced into the paperlike web, by any desired spraying or applicator or other suitable procedure, and the sheet is then dried.

The result is an artificial fibrous sheeted tobacco product which can be used in sheet form, or can be shredded and then used, in the ultimate production of articles for smoking.

The fatty acid and carbamide are preferably introduced, as indicated, either to the liquid concentrate prior to its application to the web, or to the web itself prior to the final drying procedure. However, other methods of incorporating these additives may be employed if desired. For introducing the additives, a soluble soap of the fatty acid can be made with potassium hydroxide, soda, or ammonium hydroxide in the usual way. The requisite carbamide may be combined in water solution with the fatty acid soap (potassium soap preferred). Alternatively, the fatty acid and carbamide can be dissolved in a volatile organic solvent, such as acetone.

The amount of the additives required to produce the desired beneficiating effect is relatively small. The addition of from 1.0 to 4 percent, by weight, of fatty acid and from 1.0 to 3.0 percent, by weight, of carbamide, to tobacco stems, in whatever form they may be employed, has proven satisfactory. Thus, in cases where the stems are made into a sheeted product, and where the fibrous part of the sheet is composed chiefly of such stems, the fatty acid is preferably introduced in an amount equal to from 1.0 to 4 percent of the sheet, by weight, and the carbamide is preferably introduced in an amount equal to from 1.0 to 3.0 percent of the sheet, by weight. If the fatty acid and carbamide are added in lesser amounts than mentioned above, the effect is unnoticeable. If a greater proportion of fatty acid than mentioned is employed, the smoke tends to take on a waxy note, and if a greater proportion of carbamide is used the smoke becomes ammoniacal.

ln converting sheeted tobacco material containing fatty acid and carbamide to the form of an article for smoking, it may be combined in any desired proportion (and in sheet or shredded form) with natural tobacco. In some cases, it may be used entirely alone.

However, as is well known, the production of smoking tobacco and articles for smoking does not necessarily involve the employment of an artificial sheeted tobacco material of the character described. Whatever the form or nature of the tobacco product may be, if natural tobacco stem material is present in any amount, and if it is desired to compensate for its deficiencies as a creator of desirable pyrolysis products, saturated fatty acid and carbamide can be used as additives. Their manner of use can be varied, as may be desired, e.g., the carbamide and fatty acid soap solution could be sprayed onto or otherwise applied to tobacco leaves or into intermixture with a shredded tobacco product, or they could be used as an ingredient of other additives customarily employed. 1f reconstituted tobacco is being made by the cast film process, wherein powdered tobacco in a binder is extruded as a film and then dried, the carbamide and fatty acid soap solution may be mixed with the tobacco and binder prior to casting. The proportion of fatty acid and carbamide to be used are dependent in each case upon the amount of stems or stem derivatives present.

The mode of action of the fatty acid, for which palmitic acid is preferred, is in part that of supplying a material whose pyrolysis products apparently contribute a milder smoke flavor. The overall effect is best when a commercially pure palmitic acid is used (100 percent saturated fatty acid, not over 10 percent C-1 8 present). Use of a larger percent of C-18 saturated fatty acid, or saturated fatty acid having a carbon chain length less than 16, leads to a waxy taste in the smoke when optimum amounts of the mixture are incorporated in the tobacco. The shorter chain fatty acids give an off flavor to the smoke when more than a trace is present and similarly the unsaturated fatty acids lead to undesirable flavors, particularly on storage for a time.

Carbamide does contribute some ammonia to the smoke which has the capability of reacting with some of the low molecular weight acids generated during combustion. Carbamide also has the capacity to reduce the concentration of aldehydes which are generated by combustion of cellulose and are suspected of being a major contributor to the extremely sharp and acrid smell of burning cellulose.

When used together, the fatty acid and carbamide show synergism, possibly since the ammonia incidentally released by pyrolyzing carbamide can react with acidic fragments formed from the fatty acid as well as from carbohydrates present. Whatever the mechanism, the smoke flavor has been found milder and preferable when addition of carbamide and fatty acid has been made to blends high in stems.

The preceding explanation is intended to suggest ways in which the observed action can occur but is not intended to limit the disclosure to these precise reactions.

The following examples are illustrative:

EXAMPLE 1 A mixture of lamina scrap, tobacco dust, and stems, consisting of approximately percent stem and 25 percent leaf, was extracted with water in accordance with the process described and the fibrous residue was beaten and formed into a paper-like sheet by ordinary papermaking techniques. Meanwhile, the extract was concentrated by evaporation to about 45 percent solids, and to it was added controlled amounts of the fatty acid as a potassium soap and carbamide. The fatty acid employed was commercially available extra pure palmitic acid, which upon analysis was found to contain percent palmitic acid (C-l6) and 5 percent stearic acid (C-1 8). The extract with the additives was introduced into the sheet by means ofa size press. The amount of extract added was controlled so that the amount of extractables in the dried final product was about 50 percent, the concentration of the fatty acid being 3.35 percent, by weight, of the stem portion of the reconstituted tobacco sheet, and the concentration of carbamide being 2 percent, by weight, of the stem portion of the reconstituted tobacco sheet.

As a control, reconstituted tobacco was made exactly as described above, except no fatty acid or carbamide were added to the extract.

Both sheets were shredded and made into cigarettes. When smoked by a panel of testers, cigarettes containing the additives were found to have excellent flavor, whereas cigarettes without the additives were harsh.

EXAMPLE II Reconstituted tobacco was made according to the procedure described in Example 1, except that pure palmitic acid was used, having an analysis of 90 percent palmitic acid (C-1 6) and 10 percent stearic (C-l8), in place of extra pure palmitic acid. Cigarettes made from this tobacco had excellent flavor, equal to that of the cigarettes of Example I.

EXAMPLE Ill Reconstituted tobacco was made according to the procedure described in Example I, except that food grade" palmitic acid was used, having an analysis of 70 percent palmitic acid (C-16), 25 percent stearic acid (Cl8), and 5 percent other saturated fatty acids, in place of extra pure palmitic acid. Cigarettes made from this tobacco had flavor almost as good as the cigarettes of Examples I and Il.

EXAMPLES IV Vl Reconstituted tobaccos were made according to the procedure described in Example 1, except that the fatty acids listed below were used in place of-extra pure palmitic acid. Cigaret es made from the tobaccos were characterized as indicated on the following list:

Cigarette Quality Fatty Acid Actual Analysis Stearic Acid Stearic Acid C l8-40% Not quite as Double Pressed" Palmitic Acid C l 6-50% Flavorful as Ot e saturated fa y EXAMPLE VII Natural tobacco fragments containing about .60 percent stems were powdered to such a degree that all passed through a 20 mesh (Le, 20 openings per linear inch), screen and a substantial part through a 40 mesh screen. To 500 parts of a 2 percent solution of methyl cellulose, used as a binder, was added 0.7 parts carbaf mide and 0.9 parts potassium palmitate. One hundred parts of the powdered tobacco was mixed into the solution, producing a pasty disperson. The latter was spread to form a film of such thickness that after drying in a stream of warm air to a moisture content of about percent a dry film was obtained which approximated the thickness and weight of natural tobacco. The carbamide content of ,the film was 1.1 percent, by weight, of the stem portion, and the fatty acid content was 1.2 percent, by weight, of the stem portion.

The reconstituted sheet was shredded and made into cigarettes whose flavor and mildness were superior to cigarettes made from reconstituted tobacco made as described above but without the addition of carbamide and potassium palmitate.

EXAMPLE Vlll were then blended with leaf shreds, the stems being Examples l and ll percent of the final mix. Cigarettes made from this blend were again preferred by the smoking panel over those made from the same blend using untreated crushed stems.

Obviously a similar result can be reached by spraying a carbamide-palmitic acid solution on the blended mix in Example Vlll rather than on the stems alone.

A reconstituted sheet for use as a little cigar wrapper or a binder sheet for cigars can be made by the same techniques outlined in Examples I-VII. In these cases, particularly in the little-cigar wrapper sheet, some wood fiber may be added to the tobacco sheet to strengthen it, but at the same time increasing the need for smoke flavor improvement. An illustration follows:

EXAMPLE IX Following the procedure used in Example I with a mixture of cigar tobacco of which percent was stem and 30 percent lamina, 20 percent un-bleached kraft pulp was added to the fibrous residue. To the concentrated extract was added enough palmitic acid soap and carbamide to give 1 percent palmitic acid and 4 percent carbamide, both percentages being by weight of the stems and kraft pulp portion of the reconstituted sheet. This sheet was tested by shredding and forming into cigarettes. All of the smokers preferred the cigarettes with the carbamide-palmitic additives to cigarettes which were identical except for the absence of the additives.

EXAMPLE X Following the procedure of Example IX a product was made with only the 4 percent carbamide added. Evaluation of this indicated a mild but slightly ammoniacal, flavor.

EXAMPLE XI Following the procedure of Example ll but adding only 2.5 percent palmitic acid as the potassium soap to the reconstituted sheet gave a product that the smokers found better than the control but not as good as that of Example 11.

The last two examples reflect the synergism present when fatty acid and carbamide are used.

The invention has been shown and described in preferred form only, and by way of example, and many variations may be made in the invention which will still be comprised within its spirit. It is understood, therefore, that the invention is not limited to any specific form or embodiment except insofar as such limitations are included in the appended claims.

What is claimed is:

1. A smoking product comprising a tobacco composition which includes a substantial proportion of tobacco stem material whose tasteand aroma-generating characteristics, when burned, are inferior to those of burning tobacco leaf lamina, said tobacco composition including carbarnide and a saturated fatty acid composition having a carbon chain length of l6-l8, said carbamide being present in an amount from 1.0 to 3.0 percent, by weight, of the stem material, and said fatty acid composition being present in an amount from 1.0 to 4.0 percent, by weight, of the stem material, said ,carbamide and fatty acid imparting to the stem material, when it burns, some of characteristic taste and smell of burning tobacco leaf lamina.

2. A smoking product as defined in claim 1 wherein said fatty acid composition is essentially palmitic acid.

3. A smoking product as defined in claim I wherein said tobacco composition also includes non-tobacco cellulosic material, said carbamide being present in an amount from 1.0 to 3.0 percent, by weight, of the combined stem and non-tobacco cellulosic material, and said fatty acid composition being present in an amount from L to 4.0 percent, by weight, of the combined stem and non-tobacco cellulosic material.

4. A smoking product as defined in claim 1 wherein said tobacco composition comprises an intermixture of natural tobacco and reconstituted tobacco.

5. A smoking product as defined in claim 1 wherein said tobacco composition is essentially natural tobacco.

6. A smoking product as defined in claim 1 wherein al, whereby said treated stern material, when it burns,

has imparted to it some of the characteristic taste and smell of burning tobacco leaf lamina.

Claims

2. A smoking product as defined in claim 1 wherein said fatty acid composition is essentially palmitic acid.
3. A smoking product as defined in claim 1 wherein said tobacco composition also includes non-tobacco cellulosic material, said carbamide being present in an amount from 1.0 to 3.0 percent, by weight, of the combined stem and non-tobacco cellulosic material, and said fatty acid composition being present in an amount from 1.0 to 4.0 percent, by weight, of the combined stem and non-tobacco cellulosic material.
4. A smoking product as defined in claim 1 wherein said tobacco composition comprises an intermixture of natural tobacco and reconstituted tobacco.
5. A smoking product as defined in claim 1 wherein said tobacco composition is essentially natural tobacco.
6. A smoking product as defined in claim 1 wherein said tobacco composition is essentially reconstituted tobacco.
7. A method of making a smoking product, comprising the steps of providing a tobacco composition which includes a substantial proportion of tobacco stem material, and combining with said stem material carbamide and a saturated fatty acid having a carbon chain lEngth of 16-18, said carbamide being present in an amount from 1.0 to 3.0 percent, by weight, of the stem material, and said fatty acid being present in an amount from 1.0 to 4.0 percent, by weight, of the stem material, whereby said treated stem material, when it burns, has imparted to it some of the characteristic taste and smell of burning tobacco leaf lamina.