2.1 Sampling and characterization:
The Mixed Waste Activated Sludge (MWAS) used in this study was withdrawn from mixed sludge sampling point before anaerobic digester at Beenyup Wastewater Treatment Plant (BWWTP), Western Australia. The MWAS sample consists of raw primary sludge (PS) and thickened excess activated sludge (TEAS) mixed in the ratio 65:35, as it is available in the plant. The digested sludge (DS) was collected from the sampling port of anaerobic digester of the same treatment plant. The fruit and vegetable waste (FVW) used in the current study was prepared by blending the components given in Table 1. MWAS and FVW were mixed in the ratio 1:1 and 3:1 (on a total solids basis). All the samples were freshly collected/ prepared and used for experiments to avoid any microbial contamination during storage.