The agri-food industry is at the centre of the circular economy, since the co-composting of its residual flows allows their management and adds value producing fertilisers. In this work, six composting piles were prepared combining agri-food sludge (AS), different fresh vegetable wastes (pepper waste (P), tomato waste (T), and leek waste (L), and, as bulking agents, vine shoot pruning (VS), garlic stalks (GS) and avocado leaves (AL)). Classical physico-chemical and chemical determinations and advanced instrumental methods (excitation-emission fluorescence (EEM) and gravimetric (TG, DTG and DTA) techniques) were used and compared to assess organic matter evolution and evaluate the quality of the composts obtained. The thermal profiles of the composting processes were viable to show the stabilization of the agri-food sludge with the different materials tested in the mixtures, reaching adequate levels of stabilization of organic matter. Preferential degradation of peptides and proteins was observed by fluorescence. This seemed to induce a limitation in the biodegradation of the remaining organic matter, indicating that these biomolecules are key in composting dynamics, acting as limiting components during the process. The results from thermogravimetric analysis indicated the degradation of labile compounds (e.g., carbohydrates and proteins), the most recalcitrant material becoming predominant at the maturity stage of the composting process. The rise in the thermogravimetric parameter R2 was associated with the increase in the concentration of more refracting compounds, which need more energy for their decomposition.

农业食品行业处于循环经济的中心，因为其剩余流量的共同堆肥允许其管理并增加生产价值的肥料。在这项工作中，准备了六个堆肥堆，结合了农业食品污泥 (AS)、不同的新鲜蔬菜废物（辣椒废物 (P)、番茄废物 (T) 和韭菜废物 (L)，以及作为膨胀剂的藤蔓芽）修剪 (VS)、大蒜茎 (GS) 和鳄梨叶 (AL))。使用经典的物理化学和化学测定以及先进的仪器方法（激发发射荧光 (EEM) 和重量分析（TG、DTG 和 DTA）技术）并进行比较，以评估有机物质的演变并评估获得的堆肥的质量。堆肥过程的热曲线是可行的，以显示在混合物中测试的不同材料对农业食品污泥的稳定性，达到了足够的有机物稳定性水平。通过荧光观察到肽和蛋白质的优先降解。这似乎限制了剩余有机物的生物降解，表明这些生物分子是堆肥动态的关键，在该过程中作为限制成分。热重分析的结果表明不稳定化合物（例如碳水化合物和蛋白质）的降解，最顽固的材料在堆肥过程的成熟阶段变得占主导地位。