中国食品添加剂

罗汉果提取物在实际生产过程中常残留有啶虫脒、噻虫胺、吡虫啉、噻虫嗪、霜霉威等多种农药，本文对罗汉果提取物中多种农药残留的协同脱除工艺进行系统研究。采用动态吸附模式，考察了常规大孔吸附树脂、专用脱农残树脂及阳离子交换树脂对罗汉果提取物、罗汉果苷V(MV)和农药残留的吸附分离行为，并比较了不同洗液类型、乙醇洗脱梯度与浓度以及上柱量等工艺条件对脱农残效果和MV回收率的影响。结果表明，罗汉果提取物中多种农药残留的较优脱除工艺为：罗汉果浓缩汁经大孔吸附树脂吸附、乙醇解吸并浓缩水相后，再通过专用脱农残树脂与阳离子交换树脂串联层析系统处理。经该工艺处理后，提取物中啶虫脒、噻虫胺、吡虫啉、噻虫嗪和霜霉威含量均可降至10μg/kg以下，且MV回收率保持在90%以上。研究结果还表明，仅通过筛选特定型号吸附树脂、采用酸碱洗脱或梯度乙醇洗脱，难以实现多种农药残留的精准脱除。在所考察的8种专用脱农残树脂中，LKS11在农残脱除率、MV回收率及脱除精度等方面综合表现最佳。经LKS11—001×7串联层析系统处理后，提取物中上述5种农药残留均低于10μg/kg；在该控制标准下，LKS11—001×7树脂对罗汉果提取物的处理量可达（1007.21±13.83） g/L以上。

Monk fruit(Luo Han Guo) extract is often contaminated with various pesticide residues,including acetamiprid,clothianidin,imidacloprid,thiamethoxam,and propamocarb during industrial production,this study systematically investigated a synergistic process for the simultaneous removal of multiple pesticide residues from monk fruit extract. Using dynamic adsorption mode,the adsorption and separation behaviors of conventional macroporous adsorption resins,specific pesticide-removing resins,and cation exchange resins toward the extract,mogroside V(MV),and pesticide residues were examined. The effects of different washing solutions,ethanol elution gradients and concentrations,and loading volumes on pesticide removal efficiency and MV recovery were also evaluated. The results indicated that the optimal process for removing multiple pesticide residues consists of the following steps : adsorption of the concentrated juice of monk fruit onto macroporous adsorption resin,elution with ethanol and concentration of the aqueous phase,and subsequent treatment with a tandem column system combining a specific pesticide-removing resin and a cation exchange resin. After this treatment,the contents of acetamiprid,clothianidin,imidacloprid,thiamethoxam,and propamocarb in the extract were all reduced to below 10 μg/kg,while the recovery of MV remained above 90%. Furthermore,the results showed that simply selecting specific types of adsorption resins,using acid/base washing,or applying gradient ethanol elution could not achieve precise removal of multiple pesticide residues. Among the eight specific pesticide-removing resins evaluated, LKS11–001×7 exhibited the best overall performance in terms of pesticide removal rate, MV recovery, and removal precision. After treatment with the LKS11–001×7 tandem column system,the contents of all five pesticide residues in the extract were below 10 μg/kg. Under this control standard, the processing capacity of LKS11 resin for monk fruit extract reached(1007.21±13.83) g/L.