US2158565A - Process for making harsh tobacco mild and the resultant product thereof - Google Patents

Description

Patented May 16, 1939 UNITED STATES PATENT OFFICE MILD AND THE THEREOF RESULTANT PRODUCT Andrew T. Andrews, Rahway, N. J., assignor of one-half to Standard Commercial Tobacco Company, Inc., New York, N. Y., a corporation of Delaware No Drawing. Application August 27, 1937, Serial No. 161,336

11 Claims.

The present invention relates to the treatment of tobacco, and has for its primary object certain improvements in the method of treating tobacco, particularly for the purpose of rendering harsh tobacco mild, as well as in the treated tobacco as an article of manufacture.

As is well known, the matured leaves of the green tobacco-plant are prepared for consumption by curing, the latter being effected usually by exposing the tobacco leaves to air, the sun, or fire. The cured leaves are allowed to absorb moisture until they become pliant. They are then assorted and packed in boxes, hogsheads, or bulks, where the tobacco undergoes a fermentation that 15 develops aroma and flavor. Afterward it is worked up in the various forms suitable for market.

The ingredients of cured tobacco are, in general, nicotine and other alkaloids, resinous and fatty 90 substances, glucose, starch, aibuminoids, pectic acid, citric acid, malic acid, oxalic acid, acetic acid, nitric acid, ammonia, cellulose, silica potash, lime and ash. The quantities of these ingredients vary, of course, with different varieties and grades of tobacco.

When tobacco is ignited, as when it is smoked in a pipe or in the form of cigars or cigarettes, chemical reactions take place, probably involving oxidation of many of the above-enumerated ingredients, forming nitrogenous products which tend to irritate the smokers throat and nose. The quantity of irritant products so formed is greatest in the so-called harsh tobaccos. An adequate moisture content tends to neutralize or a obviate this irritating action.

It has now been found, as a result of extensive research, that when harsh tobacco is treated with parafiin or other wax, in the manner hereinafter more specifically set forth, it loses all its irritating properties and becomes mild when smoked in any form.

A preferred manner of effecting the aforesaid treatment is by applying the parafiin or other wax to the tobacco, and such application is preferably carried out with the aid of an emulsion of the waxy treating agent. The emulsion, according to this invention, may be applied to the tobacco either by spraying thereon or by dipping the tobacco into a bath of the emulsion. The resultant wax-treated tobacco is then dried, preferably at a temperature slightly above the melting point of the paraffin or other wax used.

The emulsification of the paraffin or other wax may be effected according to conventional emulsifying procedure, using for such purpose an emulsification agent such as stearic acid, trlethanolamine, diglycol stearate or other suitable and/or desirable substance capable of forming an emulsion with the paraffin or other wax employed.

In connection with the emulsification, it is sometimes desirable, particularly when the emulsifying agent consists of stearic acid or stearates which, as they often do, may contain impurities in the form of oleic acid and the like, to add to the treating emulsion a sufficient quantity of iodine or potassium permanganate or other suitable and/or desirable oxidizing agent for oxidizing such impurities before applying the emulsion to the tobacco. This oxidation frees any unsaturated hydrocarbons present in the substances used in the emulsion from a rancid odor which otherwise would be present in smoking tobacco treated by this process.

The paraffin or Wax applied to the tobacco by the spraying or dipping operation spreads, during the aforementioned drying step which is effected at a temperature slightly above the melting point, over the entire surface of the coated tobacco, thus forming a very fine and essentially continuous film on such surface so that the tobacco is, in eifect, enclosed in a Cellophane-like envelop.

This envelop functions both mechanically, i. e. physically, as well as chemically, to obviate the irritating effects of the harsh components formed during smoking of the tobacco. As above mentioned, cured tobacco is generally allowed to absorb sufficient moisture to maintain it in pliant condition. This moisture also assists in making the tobacco mild during the smoking. It is therefore obviously desirable to prevent this moisture from drying out. The waxy envelop produced according to the present invention effectively preserves the treated tobacco from atmospheric changes of temperature and humidity which would tend to prejudice the moisture content thereof. The desirable pliant condition is thus retained, and there is no crumbling of the tobacco due to brittling thereof. Furthermore, the mechanical seal preserves the delicate aromatic elements and flavor of the tobacco. Also the paraffin keeps the tobacco soft and pliant even after moisture is driven off.

Another important physical function of the coating of this invention is that the waxy treating agent acts as a lubricating agent during the cutting of the treated tobacco leaves and tends to minimize, after cutting, the losses due to shorts resulting on the cutting machine and during handling of the tobacco.

In connection with the chemical action of the treating agent according to the present invention, it is to be noted that the said agent comprises, as an essential ingredient, a mixture of hydrocarbons. When the treated tobacco is ignited, as during smoking, a chemical reaction takes place whereby these hydrocarbons in the presence of air produce water thus introducing into the smoked mixture a significant quantity of moisture which helps to make the tobacco mild by providing an atmosphere in which the formation of irritants is rendered difficult if not altogether impossible.

A common method currently employed for keeping tobacco mixtiues moist consists in admixing the same with a hygroscopic substance, such as glycerine or diethylene glycol. These auxiliary substances may be used in making cigarettes or other forms of smoking tobacco from tobacco treated according to the present invention, but they are not at all necessary. Whether they are used or not, the tobacco can be exposed to climatic conditions which dry up the moisture normally provided or retained by the hygroscopic substance'and still be mild when smoked.

Iii-making cigarettes or other forms of tobacco used for smoking purposes, it is not necessary to treat the entire blend according to this invention, but it is sufficient usually to treat only the harshest tobacco. Admixture of this treated tobacco with tobacco of better quality will result in a very mild product.

As hereinbefore indicated, the preferred treating agent is paraflin. This parafiin may be a soft paraffin-melting at 38-50 C. or it may be a hard paraffin melting at 56-76 C. Instead of paraflin wax, other'suitable waxes such as ceresine, beeswax, Japan wax and carnauba Wax may also be used. The last-named waxes are preferably used in admixture with paraflin, a typical admixture comprising for example 8 parts of carnauba wax, 17 parts of paraflin wax, 2 parts of stearic acid, 0.9 part of triethanolamine, 120 parts of water.

The quantity of parafiin and/ or other wax used according to the present treatment to render the tobacco mild will depend upon the nature of the tobacco being treated and upon the percentage of produced nitrogenous compounds which cause the nose'and throat irritations. Generally speaking, the "percentage of parafiin emulsion applied to the tobacco may vary from to 50% of the weight of the latter. The percentage of wax in the final product will, of course, depend upon the particular composition of the emulsion. As will be apparent from the following illustrative examples of typical methods of carrying out the present invention, the percentage of wax in the product may range from about 1.5% to about 4.4%.

Examples 1. A blend of cigarette tobaccos consisting of 10 pounds of burley tips tobacco, which is of relatively poor grade and tends to be harsh, and of 90 pounds of tobacco which is of relatively high quality and tends to be mild, is coated by immersion in a bath consisting essentially of paraffin emulsified in a conventional emulsifying machine with stearic acid, 0.45 pound of the latter being used per 4.4 pounds of parafiin, with 0.175 pound of triethanolamine and 20 pounds of water. The coated tobacco mixture is withdrawn from the emulsion bath, and is dried for the length of time required to pass the tobacco through a Proctors machine. It is then used in making cigarettes.

2. 100 p ounds of cured tobacco leaves which are excellently adapted for forming cigar fillers but which tend to be harsh are sprayed with an emulsion containing 1.5 pounds of paraffin per 0.4 pound of diglycol stearate, and 13 pounds of Water, the stearate functioning as the emulsifying agent, and the spraying being continued until the entire emulsion has been sprayed onto the tobacco. After drying, the treated tobacco is made up into fillers in usual manner.

3. 100 pounds of pipe tobacco mixture is treated by spraying with an emulsion containing 2.35 pounds of paraffin, 1.2 pounds of beeswax, and 0.35 pound of 'stearic acid, 0.12 pound of triethanolam ine, and 16 pounds of water. The amount of emulsion added constitutes about 20% of the mass. After drying, the treated mass is ready for smoking in a pipe.

Having described the invention, what is claimed and desired to protect by Letters Patent is:

1. Wax-coated smoking tobacco.

2. A smoking tobacco mixture comprising relatively harsh tobacco and relatively mild tobacco, the relatively harsh tobacco being provided with a coating of hydrocarbonaceous Wax.

3. A smoking tobacco blend comprising portions treated with paraffin to minimize the formation of irritating reaction products when the tobacco is ignited.

4. Smoking tobacco comprising less than 5% by weight of hydrocarbonaceous wax adapted to produce moisture during the smoking of the tobacco.

5. Smoking tobacco as defined in claim 4, said hydrocarbonaceous wax consisting essentially of parafiin.

6. A smoking tobacco mixture comprising tobacco and -a hydrocarbonaceous wax which tends to produce moisture in the mixture during the smoking thereof.

7. Comminuted smoking tobacco comprising tobacco particles encased in a Cellophane-like envelope of a hydrocarbonaceous wax, whereby the moisture content of the tobacco is stabilized.

8. Smoking tobacco comprising elements encased in a substantially continuous enveloping film of paraffin.

9. A smoking tobacco mixture comprising tobacco and parafiin wax.

10. An agent for treating harsh tobacco to render it mild consisting of an emulsion of a hydrocarbonaceous wax.

11. A tobacco coating composition consisting of an emulsion comprising parafiin and an emulsifying agent therefor.

ANDREW T. ANDREWS.