System and method for pasteurizing citrus juice using microwave energy

A method for pasteurizing citrus juice while retaining optimum flavor, the method comprising the steps of.

• continuously flowing the juice through microwave-transparent tubing, the tubing having a diameter sufficient to minimize a temperature gradient thereacross by maintaining a maximum depth of juice from a wall of the tubing;
• and
• exposing the juice flowing through the tubing to microwave energy in a series of steps to sequentially heat the flowing juice to a predetermined final temperature in the range of 70 to 95 degrees centigrade, the final temperature sufficiently high to pasteurize the juice but insufficient to cause a detectable loss of flavor in the juice.

A system for pasteurizing a liquid while retaining optimum flavor, the system comprising:

• a plurality of sources of microwave energy for heating the liquid;
• means for continuously flowing the liquid so as to expose the liquid sequentially to the microwave energy sources, thereby raising a temperature of the liquid sequentially;
• means for controlling a total microwave power emitted and the flowing means to control a time the liquid is exposed to microwave energy, the exposure time sufficient to pasteurize the liquid and insufficient to cause a detectable loss of flavor in the liquid.

A system for pasteurizing citrus juice while retaining optimum flavor, the system comprising:

• a plurality of sources of microwave energy for heating the juice;
• means for continuously flowing the juice between a juice inlet and a juice outlet so as to expose the juice sequentially to the microwave energy sources, thereby raising a temperature of the juice sequentially;
• means for controlling a total microwave power emitted and the flowing means to control a time the juice is exposed to microwave energy, the exposure time sufficient to pasteurize the juice and insufficient to cause a detectable loss of flavor in the juice, the exposure time further sufficient to raise the juice temperature to a final temperature sufficient to inactivate undesirable microorganisms and enzymes but insufficient to cause a substantial deterioration of flavor.