基于低共熔溶剂同时清洗植物性食品中多种污染元素可行性研究

Feasibility study on removal of multi-polluting elements in plant food by deep eutectic solvents

中文关键词:  低共熔溶剂  植物性食品  多种污染元素  清洗  变异系数法

英文关键词:deep eutectic solvents  plant food  multiple-polluting elements  removal  variation coefficient method

中文摘要:

      目的 探究基于低共熔溶剂(deep eutectic solvents, DESs)同时清洗植物性食品中多种污染元素的可行性。方法 室温下, 以六偏磷酸钠为氢键受体, D-葡萄糖酸、山梨醇和尿素为氢键供体制备3种新型DESs, 即六偏磷酸钠-D-葡萄糖酸(sodium hexametaphosphate-gluconic acid, SHMP-GlcA)、六偏磷酸钠-山梨醇(sodium hexametaphosphate-sorbitol, SHMP-Sbt)及六偏磷酸钠-尿素(sodium hexametaphosphate-urea, SHMP-Ur), 测定3种DESs的黏度、密度、熔点和pH, 并利用傅里叶变换红外光谱法(Fourier transform infrared spectroscopy, FTIR)、热重法(thermo-gravimetry, TG)进行表征。超声辅助下, 将3种DESs用于清洗植物性食品中22种污染元素, 利用电感耦合等离子体质谱法(inductively coupled plasma-mass spectrometry, ICP-MS)测定清洗前后样品中7种重金属元素(Mn、Ni、Cu、Zn、Cd、Ba和Pb)、1种类金属元素(As)、14种稀土元素(La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb和Lu)的含量, 并探究DESs的残留量。结果 DESs的黏度、密度和熔点与氢键的形成有关, FTIR结果表明DESs中存在氢键。pH与DESs前体组分有关。SHMP-GlcA、SHMP-Sbt和SHMP-Ur的分解温度分别为185、348和167℃。与纯水清洗对照相比, DESs对植物性食品中多种污染元素的清洗效果大幅提高; 变异系数法赋权综合评分显示, SHMP-GlcA对元素的去除率最优(综合评分0.6281), 次之SHMP-Ur(综合评分-0.1335), SHMP-Sbt第三(综合评分-0.4946)。DESs在样品中残留的磷元素含量不超过磷酸盐类物质的每日最大容许摄入量(70 mg/kg bw, 以P计)。结论 制备的低挥发性的新型DESs能高效去除植物性食品中多种污染元素, 在保障食品安全方面具有应用前景。

英文摘要:

      Objective To explore the feasibility of simultaneous cleaning of various contaminated elements in plant food based on deep eutectic solvents (DESs). Methods Three kinds of new DESs were prepared at room temperature by sodium hexametaphosphate as hydrogen bond acceptor with D-gluconic acid, sorbitol and urea as hydrogen bond donors, namely sodium hexametaphosphate-D-gluconic acid (SHMP-GlcA), sodium hexametaphosphate-sorbitol (SHMP-Sbt) and sodium hexametaphosphate-urea (SHMP-Ur). The viscosity, density, melting point and pH of DESs were measured, and the DESs were characterized by Fourier transform infrared spectroscopy (FTIR) and thermos-gravimetry (TG). With ultrasound assistance, 3 kinds of DESs were used to clean 22 kinds of polluting elements in plant food. The content of 7 kinds of heavy metal elements (Mn, Ni, Cu, Zn, Cd, Ba and Pb), 1 kinds of metalloid element (As) and 14 kinds of rare earth elements (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) in the samples before and after cleaning were determined by inductively coupled plasma-mass spectrometry (ICP-MS), and the residual amount of DESs were explored. Results The viscosity, density and melting point of DESs were related to the formation of hydrogen bonds. The FTIR results showed that hydrogen bonds existed in DESs. The pH values were related to the precursor components of DESs. The decomposition temperatures of SHMP-GlcA, SHMP-Sbt and SHMP-Ur were 185, 348° and 167°C, respectively. Compared with the removal effect of pure water, the removal effect of DESs on multiple polluting elements in plant food was substantial improved. The comprehensive score of variation coefficient method showed that SHMP-GlcA had the best removal rate of elements (comprehensive score was 0.6281), followed by SHMP-Ur (comprehensive score was –0.1335), and SHMP-Sbt was the third (comprehensive score was –0.4946). The residual phosphorus content of DESs in the sample did not exceed the maximum daily intake of phosphates (70 mg/kg bw, calculated as P). Conclusion Novel types of DESs with low volatile is prepared, which can effectively remove multiple polluting elements in plant food, and has application prospects in ensuring food safety.