Hong Weiling

Determination of Airtightness of Cigarette Packets by Negative Pressure Air Extraction Method

For determining the airtightness of cigarette packets accurately, a negative pressure air extractionmethod was studied, the key test parameters were determined and the method was verified. The airtightnessof packets of major domestic cigarette brands was detected by this method. The results showed that: 1) Theappropriate detection conditions were air extraction volume 200 m L/min, packet perforation depth half ofpacket thickness. 2) The coefficient of variation of detection results was less than 1%, it indicated that therepeatability of this method was good. 3) The average airtightness of hard packets(-3.508 k Pa) was betterthan that of soft ones(-1.138 k Pa), and airtightness differed greatly between the hard and soft packets ofdifferent brands. The proportion of packets whose air tightness was better than the average level reached60% for hard packets, while which was only 33.33% for soft packets.

Changes of Aroma Components in Tobacco from Different Stalk Positions before and after Dry Ice Expansion

The acidic, neutral and basic aroma components in upper, middle and lower leaves of flue-cured tobacco before and after dry ice expansion were extracted with simultaneous distillation and extraction (SDE), and then analyzed by GC/MS with internal standards. Sixteen basic components, such as pyrazine, thiazole, pyrrole, and etc., seventeen netrual components, furaldehyde, linalool, β-ionone, and etc., and fifteen acids, propionic acid, 2-methyl valeric acid, benzoic acid, lauric acid, and etc., were quantitated. The results showed that: 1) the contents of isovalerate, valeric acid, beta-methyl valeric acid, hexanoic acid, octanoic acid, nonanoic acid, lauric acid, oleic acid and myristic acid in the expanded tobacco reduced, while the contents of butyric acid and benzoic acid remarkably increased; 2) of the neutral components, isophorone and citronellol changed little, and the damascenone in expanded middle and lower leaves increased dramatically, the other fourteen components decreased with different degrees; the changes of thiazole, pyrrole, pyrazine and 2-ethyl-3-methyl-pyrazine correlated with the stalk position of tobacco leaves, and the other basic components reduced.