加工过程对稻麦重金属含量影响研究进展

Advances in Research on the Influence of Processing on the Contents of Heavy Metals in Rice and Wheat

稻麦是我国的主要粮食作物,其在生长过程中易富集重金属元素,稻麦中的重金属元素通过供应链进入人体,摄入过量的重金属元素会对人的健康造成极大损害。由于我国部分种植地区的土壤或灌溉水源存在受工业排放废弃物污染的现象,使农作物的重金属含量超标,从而对食品安全造成很大威胁。目前研究表明稻谷和小麦中的重金属含量受加工过程和方法的显著影响,稻谷的砻谷、碾米等工艺可以不同程度地降低大米的重金属含量,小麦的制粉工艺也有降低小麦粉重金属含量的效果;加工中机械设备可能对产品造成二次重金属污染。明晰加工过程对稻麦重金属含量的影响对稻麦加工环节设计与控制有着重要的指导意义。本文简单介绍了重金属在稻米和小麦中存在的化学价态以及在各部分结构中的分布规律,并重点评述了典型加工环节对大米和小麦中重金属含量的影响,并对其研究现状进行了总结梳理与分析,以期对稻麦加工中重金属污染的防治起到借鉴作用。

Rice and wheat are staple grain crops in China, however, they are susceptible to the enrichment of heavy metal elements during their growth. The heavy metal elements in rice and wheat enter the human body via the supply chain, and an excessive intake of heavy metal elements does great harms to the human health. In China, the soils or irrigation water sources in some crop growing areas are contaminated by industrial wastes, causing the contents of heavy metals in the crops to exceed the relevant standards(which poses a great threat to food safety). Current studies have shown that the contents of heavy metals in rice and wheat are greatly influenced by the processes and methods. Husking, milling and other processes can reduce the contents of heavy metals in rice to different extents;wheat flour milling can also reduce the contents of heavy metals in wheat flour. However, processing machinery may also cause secondary heavy metal contamination of products. The clarification of the influence of processing on the contents of heavy metals in rice and wheat is important for designing and controlling the processing steps of rice and wheat. This paper introduces briefly the chemical valence of the heavy metals in rice and wheat and their distribution in different in parts of the grain structures, and reviews mainly the influence of typical processing steps on the contents of heavy metals in rice and wheat. A summary of the research status is also provided, with the aim of providing a reference for preventing and controlling heavy metal contamination during rice and wheat processing.