加热卷烟水分活度的测定及随存放时间的变化  

Determination of water activity and its variation with storage time of heated tobacco product

作　　者：司晓喜 向本富 朱瑞芝 蒋薇 刘春波 张子龙 杨晨 张凤梅[1] 唐石云 汤建国 夭建华 刘志华 SI Xiaoxi;XIANG Benfu;ZHU Ruizhi;JIANG Wei;LIU Chunbo;ZHANG Zilong;YANG Chen;ZHANG Fengmei;TANG Shiyun;TANG Jianguo;YAO Jianhua;LIU Zhihua(Yunnan Key Laboratory of Tobacco Chemistry,Technology Center,China Tobacco Yunnan Industrial Co.,Ltd.,Kunming 650231,China;School of Chemical Engineering,Kunming University of Science and Technology,Kunming 650500,China)

机构地区：[1]云南省烟草化学重点实验室,云南中烟工业有限责任公司技术中心,昆明市650231 [2]昆明理工大学化学工程学院,昆明市650500

出　　处：《烟草科技》2021年第2期44-51,共8页Tobacco Science & Technology

基　　金：国家烟草专卖局科技重大专项项目“加热不燃烧卷烟的气溶胶理化特性表征及调控技术研究”[110201901002(XX-02)];中国烟草总公司标准项目“加热卷烟水分活度的测定”(2020QB010)。

摘　　要：为准确测定加热卷烟的水分活度(a_w),选择电解式传感器水分活度仪建立了加热卷烟a_w的测定方法,并研究了加热卷烟a_w和微生物指标随存放时间的变化。结果表明:(1)电解式传感器可避免丙二醇挥发对测定的干扰,优选的测试温度为25℃,样品量大于0.5 g;样品制备应在与样品水分活度相近的相对湿度环境中快速进行,无需剪碎、研磨处理;样品应密封保存,开封后立即检测。(2)方法的日内精密度和日间精密度均小于1%,35个加热卷烟的a_w在0.43~0.55之间,平均值为0.46。(3)随存放时间延长,不同初始a_w的加热卷烟芯材的a_w值和菌落总数变化不大,霉菌计数降低。此外,初始a_w较高(0.806)的芯材样品存放半个月后出现白斑,非霉变产生,可能是由于含水率过大经物理变化形成。In order to accurately measure the water activities(a_w)of heated tobacco products,a method using a water activity meter with an electrolytic sensor was developed.The variations of water activity and microbial counts in heated tobacco products as a function of storage time were studied.The results showed that:1)The electrolytic sensor could eliminate the interference caused by the volatilization of propylene glycol in the tobacco.The optimal test conditions were 25℃sample temperature and greater than 0.5 g sample mass.Dispensing with shearing and grinding,sample preparation could be carried out quickly in the relative humidity environment close to the water activity of the sample.Test samples should be sealed and detected immediately after unsealing.2)The intra-day and inter-day precisions of the method were both less than 1%.The water activities of 35 heated tobacco product samples ranged from 0.43 to 0.55 with an average of 0.46.3)With prolonged storage,the water activities and CFU did not change significantly in the tobacco materials with different initial water activities,while the mold counts decreased.The tobacco materials of heated tobacco products with an initial water activity of 0.806 displayed white spots after storing for 15 d,which was not caused by mildew and might be formed by the physical change due to excessive moisture content.

关 键 词：加热卷烟 水分活度(a_w) 测定方法 存放时间 微生物 产品质量 

分 类 号：TS411.1[农业科学—烟草工业]