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Accession nll~~;-rber 995 Lorillard h1esearch Cantar evearishas=a INORGANIC ADDITIVES FOR THE'IMPROVEMENT OF TOBACCO Submitted by: A. M. Ihrig Report number: Date: April 7, 1977 Summary or Abstract: Substantial increases in smoke pH and~smoke impact can be obtained by the application of certain calcium and potassium compounds td tobacco. These inorganic cations or anions are naturally present in tobacco and, if addi- tional amounts are properly applied, could be useful for improving cigarette impact and thus, consumer satisfaction. AMI/gm Xc: Mx. Dr, Mr, Mr. C. R. T. A, L, B. D. B. Tucker Patterson Jessup Hudson Mr, Winston Baznes. Dr. Ms. Dr, C. U. 'F. I. A. J. Lewis Sklananowski Schultz O O C.3 Library Cb O C11

INTRODUCTION: The various types of tobacco possess large variations in th~eir content of inorganic, i.e. calcium, potassium and~ magnesium, and organic, i.e. citric and oxa;lic acids, materials. For example, the quantity of Cal(calculated as CaO) ranges fr=2.22 percent in flue-cured:tobacco to 8.01 percent in burley tobacco, and the quantity of citric acid ranges from 0.78 percent in flue-cured! tobacco to 8.22 percent in burley tobacco.1 The content of these materials in the various tobaccos depends upon many factors, such as genetics, soil and climatic conditions, and cur}ng2 practices. Some of these differences are shown in Table I. The content of the inorganic substances in the leaf directly influences the yield of ash and its alkalinity. However, the effect of the inorganic materials on the leaf's smoking quality is still not completely understood. Warren Kelley3, inia series of 25 burley cigarettes, found chest impact to be directly related to the potassium content and inversely related to the chloride content, as shown in the following equation: Chest Impact = 17.28 x 4.07 (nicotine) - 7.98' (chloride)l - 7.51 (acidity) - 5.20 (pH) + 4.54 (potassium:) The introduction of low tar brands has spurred~the search for new ways to improve the taste, flavor, and impact of these cigarettes since many of the substances that contribute to these factors are "filtered out". Armitage4 and Eberhart5 claim that the unprotonated or free nicotine is absorbed more readily in the respiratory track, prod!ucingia higher level of nicotine satisfaction.5 Thus, investigators have felt that an increase in the smoke pH would increase the physiological impact by affording an increased concentration of the free nicotine in the smoke. Experiments at Lorillard have shown that smoke pH varies with~ tobacco types, for example: burley3, flue-cured7, and Turkish8 cigarettes afford smoke pH values of 7.73, 5.82, and 5.11 respectively. An examination of T'able I indicates a possible correlation between smoke pH and the concentration of the inorganic and/or organic materials in these various tobaccos. Thus, experiments were conducted whereby selected inorganic and/or organic materials were added to a tobacco blend to determine their effect on the smoke pH and thus, C) impact. ~ OJ tJ EXPERIME'NTAL : ~ C.11 An 85 lb. sample of Kent tobacco blend without final flavor and puffed tobacco~was obtained! from produ~ction. The

a1 - Z - tobacco was weighed out into 50&gm lots, sealed in plastic bags, and immediately placed in a 40°F cold room. With the exception of CaOi, the additives were dissolved in 50 to 1010 ml of water and sp°rayed on the tobaccolusing alspray cylinder to insure a uniform application. The finely divided CaO couldbe sprayed as a 101% aqueous slurry without clogging the sprayer. The tobacco samples were carefully dried under the hoodand constantly weighed in order that the moisture level, corrected for additives, was equivalent to the original moisture level. of the tobacco. The tobacco samples were made into 70 mm non- filter cigarettes using the Hauni Baby. Filter sections of 20 mm length were cut off Kent 85 cigarettes and taped to these experimental cigarettes for all smoke pH and taste evaluations. The smoke pH analN7ses were performedin accordance to the procedure outlined in Lorillard Research Report No. 85. Taste Aests were conducted by various members -of•-the- staff . DISCUSSION AND RESULTS: Table II lists the various inorganic and/or organic materials that were added to the tobacco blend, and their influence on the resulting smoke pH'and burn time. The initial experiment involved the application of LiOH. The tobacco blend was sprayed to afford a 3.01percent level of added LiOH. The LiOH was then converted, at least in part, to Li2CO3 by contacting the treated tobacco with gaseous carbon dioxide in a plastic bag. Cigarettes prepared from this LiOH/Li2CO3 treated tobacco exhibited'a good increase in smoke pH (control = 5.55, 3% Li = 7.08) and! a modest increase in burn time. Smoke panel stud'ies indicated a considerable increase in smoke impact, along with a: fairly agreeable taste. Since 1lithiumiis not normally found in tobacco, further experiments were conducted employing potassium.hydroxide as the additive. Potassium hydroxide was sprayed on tobaccoito afford Q samples containing 0.5 percent, 1.0 percent, and 2.0 percent 0 added KOH. Modest increases in smoke pH wefe observed as C.: 00 the concentration of the KOH was increased (control = 5.551, N 0.5% KOH = 5.84, 1% KOH = 6.34, and 2% KOH = 6.72). The ~ Smoking Panel studies indicated that cigarettes prepared ~ with the 2'o' added KOH tobacco yielded a much stronger smoke than the control, especially for the first two or three puffs. Towards the end of the cigarette, the sample and the control became closer in overall taste/impact characteristics. A series of samples were prepared from tobacco possessing 1.0, 2.0, and 4.0 percent added potassium nitrate. The data indicated that the added KNO3 had very little effect on the smoke pH, which would seem to indicate that the potassium ion

`h itself has essentially no effect on the pH of the smoke. Thus, the increase in the smoke pH for the KOH treated samples could be a result of the added hydroxide anion and not the added potassium~cation. The burn time for the KN03 treated cigarettes decreases with increasing KN03 concentration, indicating that the nitrate anion was helping to promote the oxidation of the tobacco. The Smoking Panel stated that these cigarettes possessed an off-taste andwere not as good as the control cigarettes. The next experiment involved the addition of CaO to the tobacco blend. Smoking results indicated that the addition of CaO had a greater influence on the resulting smoke pH than thd equivalent amounts of KOH1(2o CaO = 7.43', 2% KOH = 6.72). These experiments indicated that the inorganic additive does not have to be water soluble in order to exhibit an influence upon the smoke pH. The burn time of these CaO cigarettes was also greater than the corresponding cigarettes prepared from the KOHitreated tobacco. The smoke panel studies stated that, relative to the control, the 2% CaO cigarettes were substantially higher in smoke impact. Generally, the sharpness of the smoke decreased in the final.puffs. The conversion~of potassium hydroxidle and calcium oxide to their respective carbonates by C02 in the smoke could account for the attenuation in the smoke impact. The carbonate relationship needs further clarification. Possibly better taste characteristics can be obtained! with the carbonates ..versus the more caustic potassium hydroxides and calcium oxides. The use of carbonates may lead to an increase in the acidity of the smoke but this relationship requires further clarification. Calcium lactate is one of the few water soluble calcium compounds. Cigarettes prepared from calcium lactate treated' ,,...,tobacco exhibitedlincreased smoke pH (similar to CaO cigarettes) but not increase in burn time. The smoke panel study indicated that the taste of these cigarettes was as good as or better than the control cigarettes. A further experiment involved the addition of two and four percent diammonium phosphate to the tobacco. Only a slight increase was observed in the smoke pH (control = 5.55, G~ W 2% = 5.68 and 4% = 5.94), although there was an increase in, burn time with phosphate addition. ~ N Apparently the smoke impact from Maryland tobaccos is ~ equivalent to that from burley tobaccos, even though the L~ ~ latter contains a: higher concentration of nicotine and total volatile bases.9 However, Maryland tobaccos are high in sulfur compounds as compared to burley or flue-cured tobaccos. Thus, a set of sample were prepared containing 1.55 percent and 3.10 percent added potassium sulfate to determine whether

the smoke impact couldbe increased through sulfate anion addition. The added K2CO4 decreased the smoke pH slightly (control = 5.33, 1.55o K2S'O4 = 5.48, and 3.101 K2SO4 = 5.47). There was no detectable increase in smoke impact for the sulfate treated cigarettes. Surprisingly, the taste was not adversely affected! under these conditions. The burn time was increased, indicating that either sulfate or phosphate addition might be potentially useful for extending burn time. The addition of sulfate in the presence of applied alkaline compounds requires further clarification. In~a quick experiment, cigarettes containing 2.0 percent KOH additive were injected with 50 ul of an aqueous solution containing 4.5 ntg of K2S'O4. The solution was injected in the first 10 mm of the tobacco end. The sulfate treated!cigarettes seem to have more impact than the control cigarette which contains 2.0 percent KOH. The last set of samples were prepared to determine what effects, if any, took place when citrate of malate anions were added in~combination with certain of the before-mentioned inorganic materials (notably CaO). For the four samples listed in Table II, in no case did the resulting smoke pH equal or exceed the smoke pH of the corresponding CaO treated samples. Thus, the addition of the org~-~.nic anions only seems to moderate the affects of the added CaO~ material. Mr. Terry Jessup requested that the writer help him find a method to increase the initial smoke impact for an experi- mental 2.0 mg, tar cigarette using aniair diluted filtration system and~porous cigarette paper. It was proposed that 2.0 percent C'aOland 2.0 percent potassium citrate be added to this low tar blend. The additives were applied to a 50 pound~ sample of tobacco which was made into cigarettes inithe pilot plant. These cigarettes exhibited a substantial increase in impact but possessed an off-taste, according to the expert smoking panel. The overall series of experiments demonstrates that the addition of calcium oxide, potassium hydroxide and calcium lactate increases tli~e smoke pH and hence thie,delivery of unprotonatedinicotine. Unfortunately, the inorganic additives generate taste problems which could possibly be overcome by a judicious application of the properbas,ic compounds without sacrificing smoke impact. These experiments indicate that the overall basicity of the additive influences smoke pH and impact more than the presentce of a given cation, as exemplified by the pH differences in the potassium hydroxic3e and potassium CD nitrate samples. Calcium and potassium salts occur naturally Lj in tobacco, thus extensive toxicity studies shouldinot be OD necessary before these materials could be incorporated into 0 cigarettes. / V, GD 0

Table Z. Representative Analysis of Cigarette Tobaccasl Component Percen.t_ Flue-Cured Type 13 Burley Type 31 Maryland Type 3 2 Turkish Ca as CaO 2.22 8.01 4.79 4.22 K as K20 2.47 5.22 4.46 2.33 Mg as MgO 0.36 1.29 1.03 0.69 Cl 0.84 0.71 0.26 0.69 Phosphorous as P205 0.51 0.57 0.53 0.47 Sulfur as S04- 1.23 1.98 3.34 1.40 Alkalinity of H20 solubles as ml 1N 15.9 36.2 36.9 2.25 Acid/10&gm of tobacco Smoke pH 5.82 7.73 - 5.11 Malic Acid 2.83 6.75 2.43 3.87 Citric•Acid 0.78 8.22 2.98 1.03 Oxalic Acid 0.81 3.04 2.79 3.16 Nitrate Trace 1.70, 0.08 Trace NH3 0.0119 0.159 0.130 0.105 Ash 10'.81 24.53 21.98 14.78

F:" Table II: The Influence of Inorg,anic and/or Organic Additives on Smoke pH and Number of Puffs Description of Samples Smoke pH Number of Puffs Strongly Al kaline Additives: Control 5.55 8.9 0~.5% KOH 5.84 9.3 1.0% KOH 6.34 9.6 2.0% KOH _ 6.72 9.6 3.0% LiO H/Li2CO3 7.08 9.8 Nitrate Add 1.0% KNO itives: 3 5.57 8.4 2.0% KNO 3 5.68 7.9 4.0% KNO 3 5.70 7.4 Water insol uble alkaline additives: 1.0% CaO : 6.74 10.6 2.0% CaO 7.43 10.4 4.0% CaO 7.49 9.6 Soluble Cal cium Salt: Control 5.60 8.5 1.09% Ca lcium lactate 6•58 8•5' Ammoniurn ph osphate additives : 2.0°% (.1H 4) 2HPOA 5.68 9.8 ' 4.0% (NH 4) 2HP04 5.94 10.8' Sulfate Add itives: Control 5.53 6.6 1.55o K2 SO4 5.48 8.6 3.10% K2 SO4 5.47 9.0 Mixture of Additives: Control 5.53 6.6 2.0% CaO :, 2% potassiumicitrate 6.90 8.5 1.0% CaO , 1°s' potassiumicitrate 6.44 8'.0 2.0% CaO 1.0% KOH , 2'% potassiumicitrate, , 01.5% K2SO4 6.83 6.4 2.0%' CaO 1.0% ma;l 0.25% K2 , 2.0% potassium citrate, ic acid, 2.0% KOH, S04 and 2.0% (NH4)2HPO4 7.13 7.4 ~ C ~ N O W

LITERATURE CITED 1. "Tobacco" in ECT lst ed., Vol. 14, pp. 242-261, 2. W. R. Harlen and J. M. Moseley, The American Tobacco Company. W,. G.'Frankenburg,andi A. M. Gottscho, Ind. Eng. Chem. 44, 301, (1952). 3. Warren Kelly, Lorillard Research Center Report 528. 4. A. K. Armitage and D~. M. Turner, Nature, 226, 1231 (1970). 5. R. Eberhart and H. Schievelbein, J. Nat. Cancer Inst., 48 1785 (1972). 6. G. P. Morie, Tobi. Sci., 16, 167 (1972). 7. Warren Kelly, Lorillard Research Center Report 538. 8!. Research Notebook of A. M. Ihrig. 9. Private Communication - Terry Jessup. 10. Erston V. Miller, The Chemistry of Plants, Reinhold Publishing Corp., New York, 1957 p.16.

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