Formation Of TSNA During Tobacco Storage And The Relationship With Temperature And Nitrate Contents

Burley tobacco samples produced in4main producing areas ofChina Dazhou, Enshi, Binchuan, Wanzhou as well as USA and Malawi burleysamples were collected and analyzed for the contents of tobacco specific nitrosamine,alkaloids and nitrate to investigate the relationship between TSNA and theirprecursors in burley tobacco from different regions and varieties. Samples ofBinchuan burley tobacco, Dazhou sun-cured tobacco and Baofeng flue-cured tobaccowere collected to investigate changes in TSNA contents during storage and theirresponse to different temperature treatment. Samples of Binchuan burley tobaccowere collected to investigate response of TSNA contents to different temperature andtime treatment. Samples of Baofeng flue-cured tobacco were collected to investigatethe relationship between TSNA and nitrate, nitrite contents. The results showed that:1The TSNA contents in tobaccos from Dazhou and Binchuan were at the low levelscomparable to foreign samples and they varied greatly among samples from differentareas. The contents of total TSNAs and NNN had significantly positive correlationswith percent nicotine conversion and nornicotine contents. Contents of NNK, NATand NAB correlated significantly with nitrate contents. Comparison among differentvarieties revealed that Eyan1, Eyan3had higher nicotine conversion levels.2TSNA contents in flue-cured tobacco which had less nitrate contents were very lowand showed non-significant changes after45℃treatment. While TSNA contents inburley tobacco and sun-cured tobacco were much higher and increased rapidly afterthe treatment of45℃, with nitrate decreasing slightly and nitrite rising significantly.3TSNA contents in both burley and sun-cured tobacco increased with increase ofstorage time. The most significant increase occurred in high temperature months, forexample, from middle of April until August, especially for NNN in burley tobacco.4TSNA contents increased with increase of temperature in different temperaturetreatment. TSNA contents also increased with the increasing time, especially during12-24days.5TSNA contents increased quickly by adding directly or indirectly different typesand concentrations of nitrate and nitrite, especially in tobacco of adding nitrite. TSNA increased contents of adding directly nitrate and nitrite were significantly higher thanthem of adding indirectly.