Preliminary investigation on microflora associated with fermentation of noni (Morinda citrifolia) fruit and its nutritional components
Lawrence O Amadi, Hamilton Nwala
This study focused on microflora associated with the natural fermentation of noni fruit and its nutritional components. Microflora and nutritional components were determined by standard microbiological protocols and the methods of Association of Official Analytical Chemists (AOAC) respectively. The samples were subjected to three (3) weeks duration of fermentation in a prototype airtight glass fermenter/vessels at ambient temperature as traditionally practiced. The results revealed that the microbial counts increased from 0-14 d and decreased afterwards bacterial counts (104CFU/mL) being apparently higher than fungal counts (102CFU/mL) in fermented juice. Two genera of Gram positive bacteria were identified, Bacillus and Staphylococcus whereas four were fungal genera; three moulds, Aspergillus, Alternaria and Penicillium and a yeast genus, Saccharomyces. Most of these microbes are noted for production of pectinases, amylases and lipases which functions to soften and degrade the noni fruit. Proximate composition values of the fermented juices, 0-21 d decreased in ash, protein and total titratable acidity (TTA) whereas fat increased but moisture carbohydrate and fibre contents fluctuated. However, this investigation have been able to unravel the changes in microbiological and nutritional components of noni juice during natural fermentation. Interestingly, noni juice is nutritious, therapeutic and microbiologically safe following adequate processing protocols.