Meeker D L, Meisinger J L
J Anim Sci. 2015 Mar;93(3):835-47. doi: 10.2527/jas.2014-8524.
The rendering industry collects and safely processes approximately 25 million t of animal byproducts each year in the United States. Rendering plants process a variety of raw materials from food animal production, principally offal from slaughterhouses, but include whole animals that die on farms or in transit and other materials such as bone, feathers, and blood. By recycling these byproducts into various protein, fat, and mineral products, including meat and bone meal, hydrolyzed feather meal, blood meal, and various types of animal fats and greases, the sustainability of food animal production is greatly enhanced. The rendering industry is conscious of its role in the prevention of disease and microbiological control and providing safe feed ingredients for livestock, poultry, aquaculture, and pets. The processing of otherwise low-value OM from the livestock production and meat processing industries through rendering drastically reduces the amount of waste. If not rendered, biological materials would be deposited in landfills, burned, buried, or inappropriately dumped with large amounts of carbon dioxide, ammonia, and other compounds polluting air and water. The majority of rendered protein products are used as animal feed. Rendered products are especially valuable to the livestock and pet food industries because of their high protein content, digestible AA levels (especially lysine), mineral availability (especially calcium and phosphorous), and relatively low cost in relation to their nutrient value. The use of these reclaimed and recycled materials in pet food is a much more sustainable model than using human food for pets.
在美国,提炼行业每年收集并安全处理约2500万吨动物副产品。提炼厂处理来自食用动物生产的各种原材料,主要是屠宰场的内脏,但也包括在农场或运输途中死亡的整只动物以及其他材料,如骨头、羽毛和血液。通过将这些副产品回收利用制成各种蛋白质、脂肪和矿物质产品,包括肉骨粉、水解羽毛粉、血粉以及各种动物油脂,食用动物生产的可持续性得到了极大提高。提炼行业意识到其在预防疾病和微生物控制以及为牲畜、家禽、水产养殖和宠物提供安全饲料成分方面的作用。通过提炼处理畜牧生产和肉类加工行业原本价值较低的有机物质,极大地减少了废物量。如果不进行提炼,生物材料将被倾倒在垃圾填埋场、焚烧、掩埋或不当丢弃,会有大量二氧化碳、氨和其他化合物污染空气和水。大多数提炼出的蛋白质产品用作动物饲料。由于其蛋白质含量高、可消化氨基酸水平(尤其是赖氨酸)、矿物质利用率(尤其是钙和磷)以及相对于其营养价值而言成本较低,提炼产品对畜牧和宠物食品行业特别有价值。在宠物食品中使用这些回收和再利用的材料比使用人类食品喂养宠物是一种更具可持续性的模式。