sample="quota" bates="509910061" isource="rjr" decade="1990" class="ui" date="19921121" R J Reynolds Tobacco Company Authors: Dwo Lynm, and Steve Sink Date: November 21, 1992 Department: Product Formulation Rhenda H. Steele MAY 17 '93 557 Division: Flavor FDR: DL 1992, 6 Program: 504 Title: Burley Study (III): The Use of DOF Analyses to Monitor the Chemical Changes that take place during Heat-treatment when Tobaccos are cased with Various Sugars Objective: To determine whether DOF analyses correlate with the chemical changes that occured when Burley tobacco is cased with various sugars and heat-treated in a Sargeant Dryer Summary: Routine analyses do not provide enough information on the chemical changes that take place when tobacco is heat-treated. Analyses such as pH, the level of reducing sugar and headspace analyses can only give us a direction trend on the heat-treatment, and not very conclusive and condition sensitive. We applied the DOF results to confirm our prediction and to correlate the condition change of heating process with chemical change. We have established the correlation from analyzing the DOF formation from the tobaccos cased with different sugars and undergo high, medium and low temperature. Higher temperature or longer duration of heating produce higher DOF, and vice versa. Fructose flavor the formation of 2,5-DOF and glucose favor the 2,6-DOF formation. Ammonia added would definitely enhance DOF formation. DOFs are the flavor precursors of lower alkylpyrazines, and hydroxylalkylpyrazines. The amounts of DOF formed in cased tobaccos (fructose=HFCS > glucose >>sucrose) are simmilar to the results obtained when sugar and DAP are heated together. It is postulated that both reactions followed the same type of reactino kinetics and mechanism. Sucrose did not show much effect due to the fact that the heating was not very severe, even when the tobacco was treated with ammonia. It was of interest to note that when the HFCS is treated with ammonia, 2, 5-DOF is found in preference to 2,6-DOF. This finding is the reverse of what happens when ammonia is absent. Key Words: Burley, DOF, Casing sugars, fructose, glucose, HFCS, sucrose, heat-treatment, chemical change, Sargeant dryer, tobacco, HPLC, Maillard, monitor, ammonia, isomers. Status: This is the third paper in a series of studies related to the casing and heat treatment of Burley tobacco. Results and Discussion: In our second paper on the heat-treatment study of cased burley , we described that none of existing rougine analytical methods (i.e. nicotine, ammonia, reducing sugars, pH, etc.) (Tables 1-4), except a weak trend correlation between the decrease in pH and reducing sugars with the increase in temperature of heat-treatment was found. Specific analyses (such as amino acid, glucosamine, etc.) were examined; however, they also did not clearly demonstrate the quantitative chemical changes that take place during heating the different sugar-cased tobaccos . Although the sophisticated headspace analyses gave a trend on the formation of certain specific volatile components, alone it was not very conclusive as to what reactions took place and to what extent did they proceed . The HPLC method of deoxyfructosazine (DOF) measurement has been demonstrated to be an indicator of the chemical changes that take place with of sugar after ammoniation (quantitatively shown a certain degree of Maillard reaction fo the processed tobacco) . We have recently applied the DOF method to study a number of heat-treated cased burley tobacco samples (those used in a previous report) . The DOF results of all samples from burley tobacco cased with different sugars and at different heating conditions using the Sargeant Dryer are collectively summarized in four separate Tables (6-9). Under constant heating and time, tobaccos were separately heated at high (330°F), medium (300°F) and low temperature (230-260°F). The highlights of these DOF studies are described as follows: A) Fructose Cased Tobacco 1)Temperature factor--- DOF330 > DOF300 >> DOF230 2)Time factor---- DOF3.5min > DOF2.5min 3)Ammonia content factor---- DOF300, 1% NH3 > DOF300 4)Isomer predominate factor--- 2,5-DOF > 2,6-DOF B) Glucose Cased Tobacco 1)Temperature factor--- DOF330 = DOF300 >> DOF 248 2)Ammonia content factor---- DOF300, 1%NH3 > DOF300 3)Isomer predominate factor-- 2,6-DOF > 2,5-DOF C) HFCS Cased Tobacco 1)Temperature factor--- DOF330 = DOF300 >> DOF248 2)Ammonia content factor---- DOF300, 1%NH3 >> DOF300 3)Isomer predominate factor-- 2,6-DOF>2,5-DOF but after added1%NH3 2,5-DOF>>2,6-DOF C) Sucrose Cased Tobacco Sucrose was very slightly affected by 1)Temperature 2)Duration of heating and 3)The addition of ammonia. D) DOF Conteint in tobaccos cased with various sugars Fructose = HFCS > glucose >> sucrose E) Different Intermediate Mechanism for 2,5-DOF and 2,6-DOF: In order to explain the preference of certain isomer of DOF formation, the following Scheme 1 and 2 would demonstrate their direct relation with the kind of sugars cased on tobaccos, which confirmed by the above-mentioned results after heat-treatments. Their differences in the kinetics of formation are similar to the kinetics results when sugars and DAP reacted . Acknowledgment: The authors would like to thank to Mr. Kenneth Beard and Mr. Terry Hellard for rescuing 2 to 3 occasions of the MC emergency failure and the crisis of retrieving data from his loss in the MC system. The author are also much obliged to Mr. R. W. Williams for his patience and support in the literature search on DOF. Distribution List: Dr. Brian M. Lawrence; Dr. Gary, T. Burger; Ms. Brenda T. Hodge; Ms. R. H. Steele; Dr. Bill M. Coleman III; Dr. Bill J. Casey; Mr. Dale, B. Poindexter; Mr. R. L. Parks; Mr. Elmore, C.D.; Dr. Ken Shu; Mrs. Milly Wong; Mr. David Peele; Mr. Steve Sink; Library References Scheme I Aminosugar Formation BEST COPY formulaname formulaname formulaname BEST COPY