The ultrafiltration membrane process is widely used for fruit juice clarification, yet the occurring of fouling promotes a decline in process efficiency. To reduce the fouling potential in the membrane application in food processing, the use of natural phenolic compounds extracted from cocoa pod husk is investigated. The cocoa pod husk extract (CPHE) was prepared in phenolic nanoparticles form and added into the polymer solution at varying concentrations of 0.5 wt%, 0.75 wt%, and 1.0 wt%, respectively. The composite membrane was made of a cellulose acetate polymer using DMF (dimethylformamide) and DMAc (dimethylacetamide) solvents. The highest permeability of 2.34 L m−2 h−1 bar−1 was achieved by 1.0 wt% CPHE/CA prepared with the DMAc solvent. CPHE was found to reduce the amount of Escherichia coli attached to the membranes by 90.5% and 70.8% for membranes prepared with DMF and DMAc, respectively. It is concluded that CPHE can be used to control biofouling in the membrane for food applications.

Cocoa pod husk (CPH) which is a waste of cocoa plantation contains phenolic compounds which can be used as antibacterial agents. Phenolic compounds in CPH include phenolic acids, flavonoids and flavones. The aim of this study was to analyze the antibacterial activity of CPH extract whis was extracted by using Microwave-Assisted Extraction (MAE) method. Extraction using 96% ethanol solvent with a ratio of 1:4, 1:6 and 1:8 (w/v) for 2, 3 and 4 minutes, respectively. The extraction results with the highest total phenolic content were tested their antibacterial activity using a disk diffusion method at an extract concentration of 5, 7.5, 10 mg/mL and 15 mg/mL with three replications, respectively. The highest total phenolic content of 453 mg GAE/g dry extract was obtained from MAE treatment with a solvent ratio of 1:4 (w/v) for 4 minutes. The results of the antibacterial activity of extracts against Escherichia coli showed that inhibitory zones had formed at a concentration of 5 mg/mL. The width of the inhibition zone increases as the concentration of extract increases.

Ammonium sulfate (ZA) and nitrogen-phosphorus-potassium compound (NPK) are nitrogen-rich fertilisers commonly used by farmers. The fertilisers have high solubility in water, decay rapidly in wet soil and decompose into ammonia. Its lead into eutrophication phenomena and its absorption by crop roots becomes less effective. A facile and scalable method is developed to adsorb nitrogen-rich compounds into fish scale based powdered hydroxyapatite for slow-release fertiliser (SRF). Hydroxyapatite (HA) is a material that contains phosphorus and is a well-binding agent of nitrogen. This study is aiming at synthesizing HA from calcium-rich fish scale biowaste using wet-chemical precipitation method and coated the HA particles with ZA and NPK fertiliser. The fertiliser in solid form were combine with HA particles with the ratio of 6:1, and dissolved in aquadest. Total nitrogen content were measured periodically by using percolation method. The nitrogen release of the hybrids was compared to obtain the best kinetics model and it was found that zero order kinetics model was suitable for ZA-HA sample and Kosmeyer-Peppas model was suitable for NPK-HA sample. Vegetative growth of mustard plants were used to measure the effectiveness of SRF, and were found that combination of NPK-HA and ZA-HA were able to enhance up to 17% of the plant growth compare with conventional fertiliser.