Determination of cut tobacco blending uniformity based on thermogravimetric analysis

In order to accurately evaluate the uniformity of cut tobacco blending, the similarity of thermogravimetric reaction conversion rate curves of the blended cut tobacco sampled at different time points was calculated, and the blending uniformity of tobacco was calculated on the basis of the coefficient of variation (CV) of the calculated similarities. The proposed method was compared with the industrial standard method. The results showed that:1) The optimized conditions of thermal analysis were:tobacco particle size 380 μm, sample volume about 10 mg, the flow rate of environmental gas 50 mL/min, and heating rate 30℃/min. 2) The CV of precision test was 0.68%-1.29% and the CV of reproducibility test was 0.25%, which met the requirements of quantitative analysis. 3) There was no significant difference between the results determined by the proposed method and the industrial standard method; moreover, the test results of the proposed method had smaller CV. This method features simple operation, no chemical reagents, high precision and good reproducibility, and is suitable for the accurate determination of cut tobacco blending uniformity.