镉超标大米水解糖发酵生产2-酮基葡萄糖酸过程中镉的迁移规律

Migration law of cadmium during 2-ketogluconic acid production using hydrolysate of cadmium-contaminated rice as raw material

中文关键词:  镉超标大米  2-酮基葡萄糖酸  食品添加剂  D-异抗坏血酸钠  镉迁移

英文关键词:cadmium-contaminated rice  2-ketogluconic acid  food additive  D-sodium erythorbate  cadmium migration

中文摘要:

      目的 揭示以镉超标大米为原料发酵生产2-酮基葡萄糖酸过程中镉的迁移规律, 并获得符合食品抗氧化剂D-异抗坏血酸钠合成要求的2-酮基葡萄糖酸。方法 以正常大米、镉超标大米和混合大米为原料, 系统分析大米糖化、种子培养、2-酮基葡萄糖酸发酵、发酵产物提取等过程中镉的含量和分布, 确定镉的迁移规律及其对2-酮基葡萄糖酸发酵性能和D-异抗坏血酸钠产品品质的影响。结果 大米和碳酸钙中的镉含量对2-酮基葡萄糖酸发酵性能影响不显著(P>0.05); 发酵产物的提取过程有效降低了2-酮基葡萄糖酸中的镉含量, 提取过程中产生的酸化废渣(主要由硫酸钙和菌体组成)可富集90%以上的镉; 以镉超标大米为原料制备的D-异抗坏血酸钠的质量符合国家标准要求, 未检出镉的存在。结论 该研究为综合利用镉超标大米生产2-酮基葡萄糖酸、进而生产高附加值的食品添加剂D-异抗坏血酸钠提供了理论依据和技术支撑。

英文摘要:

      Objective To reveal the migration law of cadmium during 2-ketogluconic acid production using hydrolysate of cadmium-contaminated rice as raw material, and produce 2-ketogluconic acid meeting the requirement for synthesis of food antioxidant D-sodium erythorbate. Methods Content and distributions of cadmium during processes of saccharification, seed culture and fermentation of 2-ketogluconic acid, and 2-ketogluconic acid extraction and purification were systematically analyzed using normal rice, cadmium-contaminated rice and mixed rice as raw materials to confirm the migration law of cadmium and its effects on the fermentation performance of 2-ketogluconic acid and the quality of D-sodium erythorbate. Results The cadmium content of rice and calcium carbonate had no significant effect on the fermentation performance of 2-ketoglyconic acid (P>0.05). The extraction and purification process of 2-ketogluconic acid could effectively reduce the cadmium content in 2-ketogluconic acid. Over 90% of cadmium had been accumulated in the acidification waste residue (mainly composed of calcium sulfate and bacterial cells). The quality of sodium erythorbate produced by using cadmium-contaminated rice as raw material met the requirements of national standards, with no detection of cadmium. Conclusion The present study provides a theoretical basis and technical support for the comprehensive utilization of cadmium-contaminated rice to produce 2-ketogluconic acid for synthesizing high value-added food additive sodium erythorbate.