Study on determination of yeast causing deterioration in orange juice production line

In this study, swab samples were taken before and after CIP (Cleaning in Place) from extraction unit, squeezing and filling tank and 3 different filling units (5L, PET, cup filling) from a factory producing freshly squeezed fruit juice using cv. Valencia orange grown in Adana. Swab samples were examined in terms of yeasts, total mesophilic aerobic bacteria and lactic acid bacteria parameters. The microorganism loads were compared before and after CIP. In addition, isolated yeasts were identified by molecular methods. PCR-RFLP technique was used for characterization of yeasts and 26S rRNA D1/D2 gene regions were identified by DNA sequencing. 12 different yeast species belonging to 7 different genera were determined in orange juice production line. Candida oleophila was the most frequently isolated yeast species, while Hanseniaspora occidentalis and Clavispora lusitaniae species were identified as other dominant yeast species. Yeasts were mostly isolated from the squeezing tank, while the least isolated from 5 L filling machine in the orange juice production line. According to the results, CIP system led to significant reduction on microorganism load.