Effects of carbon dioxide in high-pressure processing on pectinmethylesterase in single-strenght orange juice

High-pressure processing (HPP) in combination with added CO was examined for efficacy in inactivating Valencia orange juice pectinmethylesterase (PME). Noncarbonated juice and carbonated juice were subjected to a range of conditions from 200 to 600 MPa, 30 to 300 s dwell time at pressure, and 15 to 50 degreesC at final processing temperature. Processing pressure magnitude, temperature, and dwell time were significant factors (p < 0.001) in the inactivation of PME. At 600 MPa and 25 degreesC final processing temperature, the addition of 12 psig carbon dioxide resulted in a decrease of pressure processing time from 346 s to 111s, while achieving an equivalent reduction in PME activity.