[关键词]
[摘要]
气候变暖已成为全球面临的严重问题,各国均积极应对。食品体系产生大量温室气体,其碳足迹已成为研究热点。本研究依据产品碳足迹全生命周期评价标准,从单元操作角度计算不同包装(真空、空气和气调包装)操作工艺碳足迹。主要研究结论如下:包装200 g熟食米饭,在真空包装和空气包装条件下,最终碳足迹为:34.05±0.01 g CO2eq和57.94±0.01 g CO2eq。气调包装条件为40% O2+20% CO2+40% N2、50% O2+20% CO2+30% N2、60% O2+20% CO2+20% N2和70% O2+20% CO2+10% N2时,最终碳足迹分别为:214.39±0.26 g CO2eq,220.53±0.26 g CO2eq,224.76±0.55 g CO2eq和230.58±0.52 g CO2eq。研究发现使用塑料制品带来的碳排放在最终碳足迹中占较高比例,并且气调包装中使用气体产生的最终碳足迹占比较高。敏感性分析显示,包装过程中碳足迹对塑料制品排放因子是敏感的;空气及气调包装过程中碳足迹对设备排放因子变化以及电力使用效率变化是稳定的,而真空包装过程对两者敏感。可通过减少使用塑料制品,降低产品最终碳足迹。
[Key word]
[Abstract]
Global warming has become a serious problem facing the international community, and all countries strive to deal with it. The food system produces a large amount of greenhouse gases (GHGs), and thus study of the carbon footprint (CF) in the food industry has become a hot topic. Based on the lifecycle assessment (LCA) method, the CFs of different packaging processes of cooked rice were calculated in the present study from the prospective of unit operations. The results showed that the final CFs of packaging 200 g of cooked rice were 34.05±0.01, 57.94±0.01, 214.39±0.26, 220.53±0.26, 224.76±0.55, and 230.58±0.52 g carbon dioxide eq under vacuum packaging, air packaging, and modified-atmosphere packaging conditions (40% oxygen+20% carbon dioxide+40% nitrogen, 50% oxygen+20% carbon dioxide+30% nitrogen, 60% oxygen+20% carbon dioxide+20% nitrogen, and 70% oxygen+20% carbon dioxide+10% nitrogen), respectively. The carbon emissions from plastic products contributed the majority of the final CF, and the final CF produced by the gases used in modified atmosphere packaging accounted for a high proportion. In addition, sensitivity analysis showed that the final CF during the packaging process was sensitive to plastic emission factors. For air packaging and modified-atmosphere packaging, CF was stable to the changes of originally applied equipment emission factors and the efficiency of electricity use, but for vacuum packaging, CF was sensitive to both of these factors. The results indicated that the final CF of a product could be reduced by decreasing the use of plastic products.
[中图分类号]
[基金项目]
广东普通高校国际暨港澳台合作创新平台(2015KGJHZ001);农产品保鲜物流共性技术创新团队(2016LM2154);广州市科技计划(201604020057)