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目的了解广州市市售普洱茶镉元素残留现状及其分布差异。方法 2013—2015年在广州市超市、批发市场、零售店、餐饮单位、茶博会、网购六类环节采集391份普洱茶样品,使用电感耦合等离子体质谱仪,依据国家食品安全风险监测工作手册中《食品中铅、镉、砷、镍、铬、铜、汞测定的电感耦合等离子体质谱分析方法标准操作程序》进行检测。结果 391份普洱茶样品镉残留量范围为0.006~0.217 mg/kg,中位数为0.032 mg/kg,均值为(0.035 9±0.019 2)mg/kg,P_(90)为0.054 9 mg/kg;其中检测结果≤0.05 mg/kg的占84.40%,0.05~0.10 mg/kg的占14.58%,>0.10 mg/kg的占1.02%;普洱茶熟茶中镉残留量高于生茶,散茶镉残留量高于饼茶,砖茶镉残留量高于散茶、沱茶与饼茶,餐饮环节采集的普洱茶镉残留量高于超市、批发市场、零售店、茶博会环节,网购环节采集的普洱茶镉残留量高于零售店环节,价位低于50元/kg的样品普洱茶镉残留量高于200~300元/kg和300元/kg以上的样品;储存年限>10 a的普洱茶样品镉残留量高于储存年限<1 a的样品。结论普洱茶中镉残留量较低,检出值均低于NY 659-2003规定的镉限量值1 mg/kg,超过8成普洱茶样品镉残留量低于检出限;普洱茶中镉元素残留量在不同工艺、形态、场所及价位等方面存在差异。
Objective To understand the current status and distribution of cadmium residues in Pu-erh tea in Guangzhou. Methods A total of 391 samples of Pu-erh tea were collected from six categories of supermarkets, wholesale markets, retail stores, catering units, tea expo and online shopping in Guangzhou from 2013 to 2015. The samples were collected by inductively coupled plasma mass spectrometry (ICP-MS), and according to the National Food Safety Risk Monitoring Manual In the “Determination of lead, cadmium, arsenic, nickel, chromium, copper, mercury in food” standard operating procedure of ICP-MS. Results The residues of 391 Pu-erh tea samples ranged from 0.006 to 0.217 mg / kg, with a median of 0.032 mg / kg and a mean of 0.035 9 ± 0.019 2 mg / kg and a P_ (90) of 0.054 9 mg / kg ; The detection results were less than 0.05 mg / kg, accounting for 84.40%, 0.05 ~ 0.10 mg / kg accounting for 14.58% and> 0.10 mg / kg accounting for 1.02%; the content of cadmium in Pu’er tea was higher than that of raw tea, The amount of residual cadmium in brick tea was higher than that of loose tea, Tuocha and cake tea, and the residual amount of Pu-erh tea in the restaurant chain was higher than those in the supermarket, wholesale market, retail store, tea expo and online shopping The cadmium residues were higher than those in the retail stores. The samples with the price lower than 50 yuan / kg were higher than the samples with 200 ~ 300 yuan / kg and more than 300 yuan / kg, and the samples with more than 10 years’ The residual amount is higher than the storage life of <1 a sample. Conclusions The content of cadmium in Pu-erh tea is lower, the detected value is lower than the limit of 1 mg / kg of cadmium prescribed by NY 659-2003, and the content of cadmium in more than 80% of Pu-erh tea samples is lower than the limit of detection. Residues in different processes, forms, places and price differences.