Orange Serum Broth is used for cultivation and enumeration of microorganisms associated with the spoilage of citrus
products, cultivation of Lactobacilli, other aciduric organisms and pathogenic fungi.

Fruit juices are generally acidic, with pH values ranging from approximately 2.4 for lemon juice, to 4.2 for tomato juice. The
low pH of these foods is selective for yeast, moulds and a few groups of aciduric bacteria. The microorganisms of greatest
significance in citrus juices are the lactic acid bacteria, primarily species of Lactobacillus and Leuconostoc , yeast and
moulds. Microbial spoilage of these citrus fruit juices are most commonly due to aciduric microbes such as lactic acid bacteria
and yeast. The lactic acid bacteria include Lactobacillus fermentum, L.plantarum , and Leuconostoc mesenteroides .
Orange Serum Broth is recommended by APHA (1) for cultivation of Lactobacilli and other aciduric organisms. Murdock and
Brokaw (5) employed Orange Serum Broth for studies of sanitary control of the processing of citrus concentrates. Hays and
Reister (4) recommended Orange Serum Broth, pH 5.5 which is accepted as a control medium by the citrus industry since
at this reaction, the medium is most productive for the growth of spoilage organisms. Dehydrated agar medium containing
orange serum was reported by Stevens (2). Orange Serum Broth is used to initiate growth of saprophytic, pathogenic fungi
in small samples