Two Years Monitoring of Ethyl Carbamate in Sugar Cane Spirit from Brazilian Distilleries

This paper describes the monitoring of ethyl carbamate concentration in sugar cane spirit from industrial distilleries in Brazil. In total, 18 distilleries from Minas Gerais and São Paulo states were evaluated, with, a total of 336 samples from August 2017 to August 2019. The ethyl carbamate was analyzed using a previously validated mass spectrometric method. Analytical curves presented coefficient of determination (R2) values higher than 0.99, and quality control samples showed a relative standard deviation (RSD) below 9%. Concentrations of ethyl carbamate ranged from not detected to 1608 µg L-1, with mean values of 294.2, 280.7 and 230.0 µg L-1 in 2017, 2018, and 2019, respectively. On average, 46, 44 and 69% of samples presented levels of ethyl carbamate below 210 µg L-1. A variety of factors may have led to distillery A having a low level (ca. 115 µg L-1) of ethyl carbamate, including controlled temperature, yeast strain, post-harvesting quality, sugar cane variety choice, and the treatment process on the sugar cane juice, which goes towards the addition of Ca(OH)2, heating and freezing. These results showed the importance of internal quality control, and that sugar cane juice treatment may be a way to decrease ethyl carbamate in the distilleries.

本论文针对巴西工业蒸馏厂产出的甘蔗烈酒中氨基甲酸乙酯（ethyl carbamate）浓度的监测情况进行了阐述。研究共评估了来自米纳斯吉拉斯州与圣保罗州的18家蒸馏厂，采集了2017年8月至2019年8月间的共计336份样品。氨基甲酸乙酯采用此前已验证的质谱法（mass spectrometric method）进行分析。校准曲线的决定系数（coefficient of determination, R²）均高于0.99，质控样品的相对标准偏差（relative standard deviation, RSD）均低于9%。氨基甲酸乙酯的浓度范围为未检出至1608 μg·L⁻¹，2017、2018、2019年的平均浓度分别为294.2、280.7与230.0 μg·L⁻¹。平均而言，分别有46%、44%与69%的样品氨基甲酸乙酯含量低于210 μg·L⁻¹。有多种因素可能导致蒸馏厂A的氨基甲酸乙酯水平较低（约115 μg·L⁻¹），包括受控的发酵温度、酵母菌株、采后原料品质、甘蔗品种选择，以及针对甘蔗汁的处理工艺——该工艺包含添加氢氧化钙（Ca(OH)₂）、加热与冷冻步骤。上述研究结果既凸显了内部质量管控的重要意义，同时也表明甘蔗汁处理工艺可作为降低蒸馏厂产成品中氨基甲酸乙酯含量的有效途径。