MICROBIOLOGICAL ASSESSMENT OF LEMON-PRESERVED FRUIT JUICE

ABSTRACT

The major challenge influencing economic value of fruit juice is the relative short shelf live. Fruit juices are spoiled primarily due to proliferation of acid tolerant and osmophilic microbiota. There is also risk of food-borne microbial infections or intoxications, which may be associated with the consumption of contaminated fruit juice. Therefore this study was designed to assess the efficacy of lemon as natural preservative by enumerating and isolating the bacteria and fungi density present in the fruit juice, to checkmate the frequency and percentage occurrence of acteria and fungi and to determine the pH and tritratable acid in lemon preserve fruit juice. Pineapple, watermelon and lemon were purchased from an open market and microbiological quality was assessed using standard microbiological method. The bacterial isolates obtained from this study are: Lactobacillus sp., Bacillus sp., Staphylococcus sp., Salmonella sp.and Escherichia coli. The pH values of the mixed fruit juices without the preservative ranged from 4.29 to 3.07 while 3.23 to 2.40 was recorded for the mixed fruits with lemon juice as a preservative. Fruit juices without lemon preservative had lower titratable acid value range 0.32 to 1.59 while for fruit juices with lemon preservative, the titratable acid value ranged from 0.82 to 2.10. The findings of this result demonstrates that lemon preservative is not an efficient natural preservative and have low quality microbiological and physiochemical properties on fruit juices.