Fig. 5

Schematic diagram for the production of β-MOS using enzyme technology. (A) Pretreatment. The copra meal sample was heated in a hot air oven at 60 °C for 12 h. For the defatting process, copra meal was boiled for 2 h in twice the volume of DI water, and then kept in 4 °C for solidification and removal of the remaining coconut oil. This process was repeated three times. After that the sample was dried again in a hot air oven for 12 h at 60 °C, before suspending in 1 L of n-hexane with stirring overnight. Then the n-hexane was removed by vacuum filtration and the defatted copra meal (DCM) was dried at 60 °C for 12 h. Then the DCM was ground, sieved through 0.2 mm mesh, and kept in 4 °C until used. (B) Bioconversion. Copra meal was suspended in DI water and β-mannanase was added to the reaction at 500 U per 2.6 g mannan. The reaction mixture was incubated for 24 h at 40 °C, 250 rpm. The soluble β-MOS product in the supernatant was collected after filtration, centrifugation, and kept at −20 °C overnight before lyophilization. Pictures of copra meal waste from the virgin coconut oil company, de-fatted copra meal after pre-treatment, and lyophilized MOS from this study are shown.