School of Animal Sciences, Virginia Tech, Blacksburg 24061.
School of Animal Sciences, Virginia Tech, Blacksburg 24061.
J Dairy Sci. 2023 May;106(5):3287-3300. doi: 10.3168/jds.2022-22508. Epub 2023 Mar 29.
Globally, ruminant production systems used to synthesize meat and milk differ tremendously in terms of their efficiency, productivity, and environmental impacts. Regardless of this variability, milk has been repeatedly identified as an essential source of nutrients for humans. The objective of this work was to characterize global contributions of fluid milk to human food and nutrient supplies, greenhouse gas emissions, and water withdrawal. Data were leveraged from the United Nations Food and Agriculture Organization to estimate global supplies of agricultural products. Trade of agricultural products and waste of those products, along with use of human food for livestock feed were accounted for before estimating human nutrient supplies. The contributions of milk to human-edible nutrient supplies were then enumerated in terms of their proportion of total nutrients supplied by the agricultural system and in terms of the human population's requirement for that nutrient. We identified that fluid milk provides over 10% of consumable supplies of vitamin B, vitamin A, riboflavin, and calcium available for humans globally. In terms of human nutrient requirements, milk provides sufficient vitamin B to meet the needs of over 60% of the global population, riboflavin to satisfy 50% of the population, and calcium and phosphorus for over 35% of the population. Compared with other foods, milk ranked among the highest in terms of nutrient-to-calorie ratio for numerous amino acids, phosphorus, calcium, and riboflavin. Conditional dependencies were identified between greenhouse gas emissions and ruminant milk and meat, but not between water withdrawal and milk production. When evaluating the trade-offs in nutrient use versus nutrient provision for producing milk or producing all ruminant products, the production of ruminants worldwide was associated with both net increases and net decreases of several key nutrients. Continued work focusing on strategies to reduce the environmental impact of milk production will improve the utility of milk for feeding the growing global population.
全球范围内，用于生产肉类和牛奶的反刍动物生产系统在效率、生产力和环境影响方面存在巨大差异。尽管存在这种可变性，但牛奶已被反复确定为人类必需的营养来源。本研究旨在描述全球液态奶对人类食物和营养供应、温室气体排放和水资源提取的贡献。本研究利用联合国粮食及农业组织的数据来估算全球农产品供应。在估计人类营养供应之前，核算了农产品贸易和这些产品的浪费，以及将人类食物用于牲畜饲料的情况。然后，根据农业系统提供的总营养中牛奶的比例以及人类对该营养的需求，来计算牛奶对人类可食用营养供应的贡献。我们发现，全球范围内，液态奶提供了超过 10%可食用的维生素 B、维生素 A、核黄素和钙供应量。就人类营养需求而言，牛奶提供的维生素 B 足以满足全球超过 60%人口的需求，核黄素足以满足全球 50%人口的需求，钙和磷足以满足全球超过 35%人口的需求。与其他食物相比，牛奶在许多氨基酸、磷、钙和核黄素的营养与热量比方面名列前茅。温室气体排放与反刍动物牛奶和肉类之间存在条件依存关系，但与水资源提取与牛奶生产之间不存在这种关系。在评估生产牛奶或生产所有反刍动物产品的营养利用与营养供应之间的权衡时，发现全世界反刍动物的生产与一些关键营养物质的净增加和净减少都有关系。继续关注减少牛奶生产环境影响的策略将提高牛奶在养活全球不断增长的人口方面的作用。
