Production of cellulose nanofibers using food grade enzymes and its application to the quality preservation of avocados
摘要
Preservation of fruits and vegetables in their raw form is closely related to the cost reduction in supply chain and minimization of food waste. For this purpose, we applied cellulose nanofibers (CNF) as a coating material for fruit. We identified the optimal conditions to produce CNF based on five commercially available edible enzymes. Firstly, we identified the best cellulase with the approval of food. Among the various food grade cellulases, Viscoflow MG, Viscozyme FG and Laminex Super 3G was selected based on the cellulose-degrading activity. For the industrial purpose, we investigated the reaction characteristics of mixture of three selected enzymes. The optimal conditions for the mixture of three enzymes were reaction temperature of 50 °C, a substrate-to-enzyme ratio of 5:1 and the addition of divalent cation Mn²+ at pH 5.0. Estimated kinetic constants of each enzyme and enzyme mixture were also investigated. Enzyme mixture showed higher Vmax suggesting the suitability for high substrate concentration. Finally, after producing CNF using wheat cellulose and enzyme mixture, we applied CNF to avocados whether CNF coating lengthen the preservation period of avocado. The application of CNF derived from wheat cellulose to avocados showed significant maintenance of appearance and remarkable prevention from weight loss.