Microbial Analysis, Mineral Contents, and Sensory Quality of Citrus sinensis (ORANGE) and Cocos nucifera (COCONUT) Blended Fruit Juices

Abstract

The study was conducted to prepare mixed fruit juice by using coconut and orange juices. A total of six (6) samples of fruit juices were analysed; pasteurized coconut and orange juice, unpasteurized coconut and orange juice, pasteurized coconut juice, unpasteurized coconut juice, pasteurized orange juice and unpasteurized orange juice.  The mineral content of the fruit juice samples such as Calcium, Magnesium and sodium were also analyzed using spectrophotometric methods. Pour plate method was used to analyze the samples to determine their microbiological safety. Identification of gram negative, oxidase and the conventional biochemical testing for gram positive and gram negative bacteria were carried out. Antibiotic sensitivity test was determined by disc diffusion method. The results revealed that sample A with pasteurized coconut and orange juice secured the highest score on sensory evaluation and showed the best consumers acceptance. Bacteria isolated include Bacillus megaterium, Bacillus polymx, Flavobacterium aquantile and Bacillus cereus while fungi isolated includes: Saccharomyces cerevisae and Candida valida. Antibiotic sensitivity test carried out on the isolates revealed that many of the bacteria manifested an intermediate to sensitive reaction to most of the antibiotics tested. All the gram-positive bacteria were sensitive to Gentamycin, ofloxacin and most were resistant to cefuroxime, ceftazidime and Erythromycin. All the gram-negative isolates were sensitive to Ciprofloxacin and ofloxacin. The mineral content of the fruit juice samples such as Calcium, Magnesium and sodium were also analyzed using spectrophotometric methods. Transmission of resistant bacteria is a potential concern with unhygienic handling of fruit juice. Better handling process and health education is crucial to preventing spread of resistant bacteria and food poisoning through these otherwise commonly consumed fruit juice.