US 3828798 A
Description (OCR text may contain errors)
ie ties .1. [191 11 2579 Harper et a1.  Aug. 13, 1974 AROMATIC TOBACCO F0 11 827,470 1/1952 Germany 31/145 PROCESS  Inventors: Patrick H. Harper, Louisville; Prim ry EXaminerMelvin D- Rein Charles F. Gregory, Middletown; Attorney, Agent, or Firm-Finnegan, Henderson, Phillip R. Fisher, Louisville, all of FarabOW & Garrett Ky.
 Assignee: Brown & Williamson Tobacco  1 CT Corporation, Louisville, Ky. A method of forming aromatic tobacco by heating the  Flled' 1972 tobacco to a predetermined temperature and then cut-  Appl. No.: 308,162 ting the tobacco while hot, for example, at a temperature such as 140 to 150 F. to thereby obtain improved smoke, aroma and appearance characteristics 131/ of the tobacco. The tobacco is moisturized before the cutting so that it manifests a moisture content of  meld of Search 131/145 1 21%-26%. During the cutting the tobacco is maintained under a pressure of 2,000-5,000 pounds exter-  References Cited many apphed' FOREIGN PATENTS OR APPLICATIONS 5 Claims, No Drawings 201,186 2/1968 U.S.S.R 131/145 I AROMATIC TOBACCO FORMING PROCESS BACKGROUND OF THE INVENTION It is desirable in the tobacco field to provide a tobacco with improved appearance and improved smoke characteristics such as aroma and taste. This is particularly true when working with pipe tobacco where a desirable final product is one which is darkened, has a plugged appearance and has improved taste and aroma characteristics. A tobacco being plugged cut or having a plugged appearance refers to tobacco that is compressed and cut in such a manner that the individual tobacco strands adhere to one another.
It has been known for some time that heat treatment of tobacco improves smoke characteristics. However, at best, these treatments such as Cavendish Process are slow and time-consuming processes including steaming, bulking and steaming under pressure, and other laborious procedures.
An example of published prior art which describes improvement of aromatic characteristics through heating is US Pat. No. 2,314,734.
Study of the available methods as outlined by the discussion above, indicates that a more effective and efficient means for enhancing the taste and aromatic characteristics of tobacco would be extremely desirable. This is particularly true when pipe tobacco is under consideration and in addition to enhancing the taste and aromatic characteristics of the tobacco it would improve the product if the process were able to enhance appearance characteristics such as by darkening tobacco and obtaining a plugged appearance.
SUMMARY OF THE INVENTION With the above comments in mind, it is among the primary objectives of the present invention to provide a process for treating tobacco which includes cutting the tobacco while it is hot and under pressure on a continuous basis to improve the smoke characteristics of the tobacco. The present method is useful in treating all tobaccos, and is particularly useful in treating pipe tobacco to improve-the smoke and aromatic characteristics, darken the color and give a plugged appearance to the cut rag. In one form of the process, the tobacco may be exposed to steam in a rotary cylinder and cut under pressure while the tobacco is still hot to achieve the desirable characteristics described above.
In summary, the present process includes a method of forming aromatic tobacco by heating the tobacco to a predetermined temperature and cutting the tobacco while hot to thereby obtain improved smoke, aroma and appearance characteristics of the tobacco. For example, acceptable results are obtained if the tobacco is cut at substantially the temperature range of 140 F. to 150 F.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Although the present invention is applicable to all types of tobacco, the present discussion will be directed toward improving the smoke characteristics of pipe tobacco. Pipe tobacco is generally handled in a conventional manner and is subjected to a conventional commercially available cutting machine for purposes of cutting the tobacco to the desired size. No material modifications in handling equipment or machinery in general use today are necessary for purposes of carrying out the newly presented process as discussed herein. For example, a five blade rotary cutter manufactured by the Molins Machine Company Limited of London, England and identified as model number 67128 has been found to operate satisfactorily.
The process is conducted in general by subjecting a mixture of tobacco with known moisture content to a heating environment at a predetermined temperature to heat the tobacco to a desired temperature. Thereafter, the tobacco is subjected to a predetermined pressure and is cut in a conventional manner while the tobacco is still hot.
Representative examples of the present process are as follows:
EXAMPLE I A cased blend of flue-cured and burley tobaccos at 20% moisture content was exposed to steam (212 F.) for 35 seconds in a rotary cylinder. The tobacco exiting the cylinder was at a temperature of 190200 F. and at a moisture content of 23%. The tobacco was cut at 18 cpi (cut per inch) on a conventional cutter while it was still hot F Four thousand pounds of pressure was applied to the tobacco in the cutter. The treated tobacco darkened in color and had a plugged appearance. The taste and aroma of the treated tobacco was improved over untreated tobacco.
EXAMPLE 2 To obtain the desired color and plugging, the tobacco must be heat treated and out while it is still hot. Cased tobacco that was heat treated and cut hot was darker with more plugging than tobacco that was heat treated and allowed to cool before it was cut. Tobacco that received no heat treatment and was cut cool was less dark with less plugging than tobacco receiving either of the above treatments. Smoke taste and aromatic attributes were more desirable on samples treated as described in Example 1.
EXAMPLE 3 (TEMPERATURE) The best combination of color and plugging was obtained when the tobacco was cut between the temperature of 130140 F. Tobacco cut at lower temperatures (below 125 F.) was unacceptably light in color and was more harsh in smoke taste attributes. When the tobacco was cut at higher temperature (above F.) some of the plugging was lost but smoke taste and aroma characteristics were improved.
EXAMPLE 4 (MOISTURE) The tobacco should be at a moisture content of 21% to 26% during cutting. Tobacco cut at moisture levels below 21% was light in color, the rag fell apart exiting the cutter, (little plugging was obtained) and smoke characteristics were not improved. Cutting tobacco at moisture contents higher than 26% is possible but mechanical difficulties are encountered. The optimum moisture content for this process is 23% with a range of 21% to 26%.
EXAMPLE 5 (PRESSURE) Cased tobacco was treated with steam as in Example 1. The tobacco was cut hot at 2,000 pounds pressure, 4,000 pounds pressure and 5,000 pounds pressure. The tobacco cut at the lower pressure was lighter in color and contained less plugging. Tobacco cut hot under 4,000 and 5,000 pounds pressure had the desired physical and subjective characteristics.
Thus, the above objectives, among others, are effectively attained.
1. The method of improving the taste, appearance and the aromatic characteristics of cut filler tobacco which comprises heating and moisturizing tobacco so that it manifests a moisture content of 21% to 26% and then cutting the tobacco into individual strands while applying pressure of between 2,000 and 5,000 pounds, the temperature of the tobacco during the cutting operation being at l30l50 F.
2. The invention in accordance with claim 1 wherein the tobacco is pipe tobacco.
3. The method set forth in claim 1 wherein the moisturizing step is accomplished by exposing the tobacco to steam.
4. The invention in accordance with claim 1 wherein the tobacco is cut hot under between 4,000 and 5,000 pounds pressure.
5. A method of forming aromatic pipe tobacco comprising: placing a cased blend of flue-cured and burley tobaccos at 20% MC in a rotary cylinder and exposing the tobaccos therein to steam at 212 F. for 35 seconds, removing the heated tobaccos from the cylinder while at a temperature of approximately 190 F. and having a moisture content of 23%, cutting the tobaccos while still heated to approximately F. at 18 cpi while subjecting the tobaccos to approximately four thousand pounds of pressure thereby obtaining improved smoke, aroma and appearance characteristics of the tobaccos.