Enzymatic Coupled Mechanical Defibrillation Process for the Production of Corn (Zea Mays) Cob Microfibrillated Cellulose: Preparation, Characterization and Evaluation as Pickering Emulsifier for Oil-In-Water Emulsion

Microfibrillated cellulose (MFC) is a type of nanocellulose having multiple functionalities. Typically, MFC was produced from mechanical high pressure homogenization process. However, this process is energy intensive and the fibrous nature of MFC often causes instrument blockage. The present study aims to utilize endoglucanse enzyme as environmentally friendly approach to pretreat fiber structure prior to undergoing mechanical defibrillation for the production of MFC from corn cob. Alkaline and bleached pretreated corn cob was treated with endoglucanase Fibercare R from 0% to 2.5% before passing through high pressure homogenizer. It was found that incorporation of 0.02% of endoglucanase was sufficient to soften the corn cob cellulose and further prevent the blockage of homogenizer. Subsequently, the 0.02% endoglucanse treated corn cob was passed through different cycles of homogenization from 0 cycle to 10 cycle for MFC production. It was observed that the water retention, zeta potential and shear viscosity of the MFC increases with homogenization cycle. MFC produced had a gel like consistency. Next, emulsifying stabilizing properties of MFC produced from cycle 0 to cycle 10 as well as their amount from 0 % to 1% were also assessed. Increase in homogenization cycle and the amount of MFC promote emulsion stability as observed from the low creaming index which is mainly attributed to the high shear viscosity and G’G’’ crossover of the emulsion. In all, the MFC derived from corn cob via enzymatic coupled with high pressure homogenization process has the potential to be used as gel like stabilizer in oil-in-water food emulsion system.