The optimal use of food components in human nutrition is key to reduce the environmental burdens of the global food system. In this life cycle assessment (LCA) case study based on Greek yogurt (GY) production systems, we explore how a system boundary expansion approach (SBES), instead of an allocation approach, can help to optimize the use of the milk components in the dairy industry for the province of Québec, Canada. GY is a high-protein-low-fat dairy product considered as a healthy high-value product for human nutrition. Its production requires large volumes of milk and generates a high-value co-product (cream) and a by-product (whey). This comprehensive LCA study compares three production technologies (centrifugation (CE), ultrafiltration (UF) and fortification (FO)) and different whey management alternatives (animal feed, biogas and fertilizer production, waste treatment). Results show that, under current Canadian market conditions in which milk production is driven by the demand for cream and surplus non-fat-solids are downcycled on the animal feed market, the CE and UF technologies, which require more raw milk than FO and produce more cream, enable better synergies in the use of milk components and improve the environmental performance of GY as compared to FO. Both CE and UF make it possible to use the excess of Canadian milk proteins in human nutrition, in compliance with circular economy principles. In this respect, neither the quantity of whey generated, nor the whey management pathway significantly influence the GY environmental footprint.

中文翻译：

---

分配不够！考虑生产和消费协同效应的系统边界扩展方法：希腊酸奶的环境足迹


在人类营养中优化利用食品成分是减少全球食品系统环境负担的关键。在这个基于希腊酸奶（GY）生产系统的生命周期评估（LCA）案例研究中，我们探讨了系统边界扩展方法（SBES）（而不是分配方法）如何帮助优化生产过程中牛奶成分的使用。加拿大魁北克省的乳制品业。 GY是一种高蛋白、低脂肪的乳制品，被认为是人类营养的健康高价值产品。其生产需要大量牛奶，并产生高价值的副产品（奶油）和副产品（乳清）。这项全面的 LCA 研究比较了三种生产技术（离心 (CE)、超滤 (UF) 和强化 (FO)）以及不同的乳清管理替代方案（动物饲料、沼气和肥料生产、废物处理）。结果表明，在当前加拿大市场条件下，牛奶生产由奶油需求驱动，剩余非脂固体在动物饲料市场上进行降级循环，CE 和 UF 技术比 FO 需要更多的原奶，并且生产更多的原料奶。与FO相比，GY含有更多的奶油，可以更好地发挥牛奶成分的协同作用，提高环境绩效。 CE 和 UF 都使得在人类营养中使用过量的加拿大牛奶蛋白成为可能，符合循环经济原则。在这方面，产生的乳清数量和乳清管理途径都不会显着影响 GY 环境足迹。