Processing and Packaging Conditions on Quality

'I'he shelf life of fruit juices and concentrates is limited primarily by microbial, enzymatic, and chemical reactions that adversely affect their nutritional quality, color, and flavor. Pasteurization requirements of freshly extracted citrus juices are based on inactivation of thermally resistant endogenous enzymes whereas requirements for reconstituted juices are based on destruction of microbial populations capable of causing spoilage. Aseptic processing produces a higher quality orange juice than hot filling; however, differences in quality may disappear during storage at ambient temperatures. Oxygen dissolved in the product, in the container headspace or permeating through the container, accelerates the rate of ascorbic acid destruction and nonenzymatic browning and reduces shelf life, although these processes will continue in its absence. The most important factor in determining the shelf life of aseptic orange juice and concentrate is storage temperature.