Certain Aspects of the Microbiology of Frozen Concentrated Orange Juice

Abstract

Investigations on sources and significance of coliforms in frozen concentrated orange juice have shown that direct contamination by handlers during the manufacture of the product is not indicated. Coliforms were isolated from aseptically harvested fruit frequently enough to indicate that they may be among normally occurring flora in the groves. Packing house washtank solutions were found to contain coliforms and could thus be one of the principal sources of the organisms in frozen orange juice products. E. coli was isolated from oranges being delivered to concentrate plants; hence its presence in the frozen concentrate need not indicate insanitary conditions in the plant. Coliform positive juice or concentrate samples reflected condition of fruit used rather than sanitary conditions of the juice line. The majority of coliform positive samples contained less than 10/100 ml.