A study of porosity, crystallinity index, and functional group of coconut dreg by pulsed electric fields duration of contact effect
This research aimed to analyze porosity based on observations using FE-SEM, crystal index, crystal size based on XRD observations, and functional groups based on FT-IR observations of coconut dreg cells due to variations in the length of pulsed electric fields (PEF) contact. Research has been done using a completely randomized design approach, and the data was analyzed using R Studio. Coconut dreg is a waste product from processing coconut into coconut milk, which is produced quite a lot, especially in West Sumatra Province, Indonesia. PEF is a non-thermal physical treatment with relatively low energy and a short duration. The contact duration of coconut dreg with the given PEF varies from 30, 60, and 90 seconds, with a frequency of 9000 Hz, a voltage of 7.8 kV, and a distance between the anode and cathode of 10 cm. Porosity, crystallinity index, size of crystal, and functional group are observed to determine the effects they cause. The findings, which were tested at a significance level of 0.001, demonstrated that PEF contact duration significantly impacts porosity by SEM observation, crystallinity index, and crystalline size by XRD observation of coconut dreg. The longer the PEF contact, the deeper the pore depth (64.5–55%), the size of the crystal becomes smaller (12.6–2.1 nm), and the resulting crystallinity index also decreases (68.9–55.7%). Functional group analysis by FT-IR also shows changes.