Anaerobic digestion is one of the potential methods widely applied for organic waste recovery to produce biogas. In this study, biodegradability of fat, oil, and grease was tested in biochemical methane potential assays and the effects of substrate to inoculum ratio ranging from 0.2-4.0 were determined. The results indicated that fat, oil, and grease is feasible to produce methane (670 mL CH 4 gVS −1 ) and the ideal substrate to inoculum ratio range of 0.5-1.0 was determined. After 60 days of experiments, maximum methane yield for the ideal ratio was 603-741 mLgVS −1 , which corresponds to 81-89% methane production. Increasing substrate to inoculum ratio showed a lag phase phenomena where methane yield may be decreased initially or started slowly, thus delaying the entire digestion process. With a higher substrate to inoculum ratio (2.0-4.0), methane yield was recorded lower than 60% and the highest methane production was 250.2 mLgVS −1 .

High volumes of sludge discharge from the aquaculture industry have relatively high pollutant content that may lead to severe local environmental problems. Anaerobic digestion is one of the technologies for sludge treatment that might be an efficient method to reduce salty aquaculture sludge production load. However, hydrolysis solubility is becoming a limitation step during the anaerobic digestion process when the occurrence of intermediate accumulation resulted from the conversion of non-soluble biopolymers to soluble organic compounds. Thus, pretreatment is required to increase the solubilization of pollutant parameters from aquaculture sludge before it is further treated in the anaerobic treatment. Therefore, this study focuses on the production of biocatalytic enzyme from the fermentation of pre-consumer supermarket waste such as pineapple dregs to increase the solubility of aquaculture sludge. The fermentation of the pineapples waste was produced via a three-month fermentation of the mixture of molasses, pineapple dregs and water, with the ratio of 1:3:10 in a tight plastic container. Apart from that, analyses showed that the enzyme possessed lipase, amylase and protease activity. The sludge solubilization pretreatment was performed at different pH values, with treatment time for 120 hours and the solubilization was evaluated by determination of Chemical Oxygen Demand (COD) and Total Ammonia Nitrogen (TAN) solubilization; the solubilization of COD and TAN increased by 80% and 50%, respectively. This finding showed that the pineapple enzyme has the capability to solubilize organic compound, which has the potential to improve hydrolysis in further anaerobic digestion process.