Detection and enumeration of salmonella spp. And salmonella typhimurium in fruit juices

Salmonella serves as the causative agent to foodbome disease. The main factor for the contamination of these fresh produce is the use of manure as fertilizer, contaminated water supplies and the poor sanitation practice by hawkers in handling and processing the fruits leads to the contamination of fresh juices with Salmonella. The objective of this study is to determine the occurrence and quantification of Salmonella spp. and Salmonella typhimurium in fruit juices by utilizing Most Probable Number (MPN) in combination with Polymerase Chain Reaction (PCR).The fruit juice samples used in the analysis were apple juice, orange juice, watermelon juice, honeydew juice and guava juice. Most Probable Number (MPN) method was used for enumeration while specific Polymerase Chain Reaction (PCR) assay was performed targeting for the virulence gene, jliC gene with expected size of 559 bp to determine Salmonella typhimurium in the fruit juices. Of these 50 samples of different fruit juices tested (n=50), only 3 samples (30%) of apple juice and 2 samples (20%) of watermelon juice present with Salmonella. 50% out of the 2 samples of watermelon juice showed 4.5 x 103 CFUlml. It was observed that all of the fruit juice samples showed estimated microbial load of Salmonella spp. as I 100 MPN/g. Negative result from Polymerase Chain Reaction assay showed that the sample did not possess the targeted gene, jliC gene, which further suggests the presence of other Salmonella serovars. However, immediate action must also be taken to monitor the quality of the fresh fruit juices by establishing a suitable control measures. This is vital to prevent any future pathogenic outbreak diseases