Four Kinds Of Heavy Metal Content In Dried Fruit Products In Zhejiang Province

In recent years, more concerned were focused on research work and supervision and inspection of heavy mental in forest foods, especially dried fruits products research and surveillance detection to get more attention.The paper research four levels of heavy metals(lead, cadmium, arsenic, mercury) by optimizing digestion and detection methods, making more accurate and reliable test results. By sampling Zhejiang edible dried fruit forest(chestnut, Torreya grandis, Hickory, ginkgo four categories),this paper will inspection levels of heavy metals,Analyzing data with The method commonly used in normal testing methods and the internationally renowned software SPSS 16.0 statistical software.Finally, we will comes safety evaluation, providing a theoretical basis for the security of Zhejiang forest product quality edible dried fruit. results are as follows:1. By comparing the two methods of digestion, microwave digestion method has come to consume less sample and reagent, more thorough digestion, simple, rapid, precision, accurate and good stability,etc. It is an ideal pre-treatment methods; The Results measured by graphite furnace atomic absorption spectrometry and atomic fluorescence spectrometer instrument is stable, wide linear range, low noise and good reproducibility. Therefore, this paper will use microwave digestion and graphite furnace atomic absorption spectrometry to determinate the lead and cadmium; use atomic fluorescence spectrophotometer to determinate the arsenic and mercury.2. Chestnut, Torreya, pecans, Zhejiang Province, of the four pass rate ginkgo nuts edible forest,ginkgo has the highest class, who were 100% pass rate in the three years; Torreya followed, in2014,there is a lot of lead fail, the overall pass rate was 96% and the remaining two years were 100%pass rate; chestnut, in 2013, have three batches of fail of lead, the overall pass rate of 98.34%, in2014,there are a lot of lead fail, the overall pass rate of 99.02%; pecans, in 2012 has four batches of fail of lead, the overall pass rate of 95.40 percent, in 2013 has six batches of fail of lead the overall pass rate of 91.43%.in 2014, there are three batches of fail of lead, the overall pass rate of 96.25%. Chestnut,Torreya grandis, Hickory, ginkgo except Pb, cadmium, arsenic and mercury detection of a three-year pass rate was 100%.3. Histogram can visually see that in Zhejiang,the heavy metal content of chestnut, Torreya, pecans,Ginkgo basically meets the normal distribution. In addition, it can be seen that the content of Pb in dried fruit is generally higher than the other three heavy metals, especially the pecan is the most dried fruit that reach the standard limit lead content of more than 75 percent,and also is the most that reach the limit value, in whith there is 56 batches of 2013 Hickory leading content of more than 75% of the standard limit, accounting for 80 percent, and the percentage of standard limit also has reached 23 percent, which should take enough attention. Ginkgo biloba has lower lead content,fewer up to the 75 percent of standard limit, rarely reach the standard limited, so its situation of security is well..4. Through single factor pollution index and comprehensive pollution index evaluation we can see:the heavy metal content of edible dried fruit forest in Zhejiang Province is in the overall level of safety,Zhejiang chestnut, Torreya grandis, Hickory, ginkgo comprehensive pollution index was less than 1.0. It is noteworthy that the comprehensive pollution index was slightly higher than the other three categories pecan, mainly due to that their lead single factor pollution index is higher, which in 2013 the single factor of Chun pecan lead pollution index is 1.023> 1.0, which is mild contamination. In 2012 and 2014,the single factor of Chun pecan lead pollution index although is not more than 1.0, but is overall between 0.70-0.90,so there is the possibility of potential contamination. Ginkgo nuts has the lower pollution than the other three in the index of each element, and pecan has the highest pollution index.