Impact of geometry parameters of packed-bed reactor on continuous orange juice clarification using pectinase immobilized on genipin-activated chitosan beads

This study evaluated five distinct packed-bed reactors for orange juice clarification using pectinase immobilized in genipin-activated chitosan beads. The tested reactors were divided into two groups for observation: those with the same volume (40 mL – varying radius and height) and those with the same radius (0.80 cm – varying height and consequently the volume). Flow tests revealed performance disparities in equal-volume reactors, attributed to uneven substrate distribution due to geometric parameters, highlighting that substrate accumulation occurs unevenly in reactors with limited surface area per volume unit. Reactors with smaller radii exhibited 45 % lower clarification efficiency, suggesting that reduced surface area and flow path limitations create zones of higher substrate concentration. No differences were observed in reactors with the same radius. Notably, stability trials demonstrated sustained activity, maintaining over 50 % of the initial levels even after 100 h. However, fruit juice clarification stability displayed particle accumulation, formation of dead zones within the reactor, and clogging, hindering juice flow completely. A promising solution was altering pump orientation, redirecting juice flow (“up-down”), reducing deposition, and extending testing to 80 h until clarification ceased. Reactor design emerged as pivotal in continuous juice clarification within packed-bed systems. Particle accumulation within the reactor substantially hampered performance.