Consortia of aerobic heterotrophic bacteria (AHB) have potential as sustainable microbial protein (MP) source in animal feed. A systematic screening of the nutritional value and safety of AHB biomass from full-scale activated sludge plants from 25 companies in the food sector was performed. The variable protein content (21-49%) was positively correlated with biomass-specific nitrogen loading rate and negatively with sludge retention time (SRT). Compared to the essential amino acid profile of soybean meal protein, AHB displayed an overall surplus of threonine and valine, and deficits in cysteine, histidine, lysine and phenylalanine. Histidine was positively correlated with COD_removed:PO₄^3-_influent and valine, isoleucine and threonine with SRT. Most AHB samples were safe apropos heavy metals, polycyclic aromatic hydrocarbons and antibiotics. Some pesticides exceeded regulatory limits, necessitating mitigation. This work highlighted that the food sector can provide high-quality MP, while retrofitting existing activated sludge plants towards high-rate processes can increase AHB quality and productivity.

有氧异养细菌（AHB）联盟作为动物饲料中的可持续微生物蛋白（MP）来源具有潜力。对来自食品业25家公司的大规模活性污泥厂的AHB生物质的营养价值和安全性进行了系统的筛选。可变的蛋白质含量（21-49％）与生物量特定的氮负荷率正相关，与污泥停留时间（SRT）负相关。与豆粕蛋白的必需氨基酸谱相比，AHB表现出苏氨酸和缬氨酸总体过剩，半胱氨酸，组氨酸，赖氨酸和苯丙氨酸缺乏。组氨酸与COD_去除呈正相关：PO ₄ ^3-_进水缬氨酸，异亮氨酸和苏氨酸和SRT。大多数AHB样品都是安全的重金属，多环芳烃和抗生素。一些农药超过了法规限制，因此有必要进行缓解。这项工作强调了食品部门可以提供高质量的MP，而将现有的活性污泥厂改造为高速率流程可以提高AHB的质量和生产率。