Usage of enzymes and adsorbents in fruit juice clarification

In this study, the use of enzymes (100-250-400 U), adsorbent, temperature (25-40-55 °C) and reaction time (60- 120-180 min)on the turbidity, flavonoid substance, phenolic substance, reducing sugar and protein concentration of cherry, pineapple and kiwi juice, effect was investigated using optimal design with RSM (Response Surface Methodology). For this purpose, a study set consisting of 22 experiments for cherry and 23 experiments for pineapple and kiwi were created using the Design Expert software. Protease, cellulase, amylase and pectinase enzymes were used as enzyme mixture. Sodium alginate, silica gel, florisil and chitosan were tried as adsorbent, and chitosan was chosen as the adsorbent that reduced the turbidity the most. Each of the experimental sets prepared by the Design Expert software was applied separately to the fruit juices, first only the enzyme mixture was added and kept at certain temperatures and duration in the set. The turbidity values, reducing sugar and protein concentrations, and flavonoid and phenolic substance contents of the fruit juices obtained in the study were determined spectrophotometrically. As a result of the analyzes made in RSM, the use of enzymes in fruit juices reduced turbidity; it was determined that the turbidity increased depending on the amount of adsorbent used in the RSM sets. The amount of phenolic and flavonoid substances in cherry juice showed a tendency to increase as the amount of enzyme and adsorbent, temperature and time increased. The amounts of flavonoid substances in pineapple juice and phenolic substances in kiwi juice were not affected by the study parameters. Protein concentration increased with increasing enzyme amount and working time in all fruit juices.