Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing, China.
China Biotech Fermentation Industry Association, Beijing 100833, China.
Sci Total Environ. 2022 Apr 20;818:151706. doi: 10.1016/j.scitotenv.2021.151706. Epub 2021 Nov 17.
China is the world's leading producer of the flavor-enhancer monosodium glutamate (MSG), which is mainly produced by maize starch fermentation. Four typical scenarios (Scenario 1-Scenario 4) of MSG production from 2008 to 2019 in China were established for life cycle environmental impact assessment. Values for five midpoint environmental impact categories [primary energy demand (PED), resource depletion-water use (WU), global warming potential (GWP), acidification potential (AP), and eutrophication potential (EP)] were calculated with eFootprint based on data collected in China. The environmental impacts of producing 1 t of MSG in China in terms of PED, WU, GWP, AP, and EP were 52,800 MJ, 169,000 kg, 4590 kg CO eq, 42.1 kg SO eq, and 6.35 kg PO eq, respectively, in 2019. The life cycle of MSG from cradle to gate includes maize cultivation (high WU values), and the MSG production process (high PED, GWP, AP, and EP values). The normalization results of environmental impacts significantly decreased from S1 to S4 with the improvement in cleaner production in recent ten years. Sensitivity and uncertainty analyses identified steam for MSG production, irrigation water, and ammonia volatilization during maize growth as the three main factors affecting the environment. There were obvious differences in calculated environmental impacts depending on the maize cultivation data source; i.e., data from the Ecoinvent 3.1 database, or collected data for the maize-wheat rotation system in north China or the maize monoculture system in northeastern China. This demonstrates the importance of collecting local data rather than applying database from other world regions. Compared with the use of coal and natural gas, the use of biogas to produce steam had much lower PED, WU, and GWP. Which types of alternative energy to use and the replacement ratio should be based on the actual resource reserves in each region.
中国是世界上领先的味精（MSG）生产国，味精主要通过玉米淀粉发酵生产。为了进行生命周期环境影响评估，建立了中国 2008 年至 2019 年味精生产的四个典型情景（情景 1-情景 4）。使用基于在中国收集的数据的 eFootprint，计算了五个中点环境影响类别[一次能源需求（PED）、资源枯竭-用水量（WU）、全球变暖潜能（GWP）、酸化潜能（AP）和富营养化潜能（EP）]的值。2019 年，中国每生产 1 吨味精的 PED、WU、GWP、AP 和 EP 环境影响分别为 52800 MJ、169000 kg、4590 kg COeq、42.1 kg SOeq 和 6.35 kg POeq。味精从摇篮到大门的生命周期包括玉米种植（高 WU 值）和味精生产过程（高 PED、GWP、AP 和 EP 值）。近年来，随着清洁生产水平的提高，从 S1 到 S4 的归一化环境影响显著降低。敏感性和不确定性分析确定，MSG 生产用蒸汽、灌溉用水和玉米生长期间氨挥发是影响环境的三个主要因素。由于玉米种植数据来源的不同，计算出的环境影响存在明显差异；即来自 Ecoinvent 3.1 数据库的数据，或来自中国北方玉米-小麦轮作系统或中国东北玉米单作系统的收集数据。这表明收集当地数据而不是应用其他世界区域的数据库的重要性。与使用煤炭和天然气相比，使用沼气生产蒸汽具有更低的 PED、WU 和 GWP。应根据每个地区的实际资源储量选择使用哪种类型的替代能源以及替代比例。
