Microbiological studies and sensory evaluation of breadfruit and cassava co-fermented into gari analogue

Abstract

This study focused on the processing of breadfruit and cassava co-fermented into gari analogue. The microbial load was determined and the microbes associated with the fermentation were identified. The shelf life of the co-fermented gari analogue samples was also determined. A portion of both mature cassava tubers and matured but unripe breadfruit (Artocarpus altilis) was co-fermented (100:0, 0:100, 80:20, 70:30, and 60:40 Cassava: Breadfruit) to obtain gari analogue. The samples were evaluated for microbial loads (total viable, total yeast and mould count and total lactic acid bacteria counts). The products were subjected to sensory analyses using a 7-point hedonic scale. Data obtained were subjected to descriptive and inferential statistics. The results showed that six bacteria species were isolated from the fermenting mash, Corynebacterium manihot, Lactobacillus plantarum, Bacillus subtilis, Bacillus coagulans, Bacillus species and Corynebacterium species. Also isolated were Saccharomyces cerevisae, Saccharomyces fragilis, Saccharomyces rouxii and Geotricum candidum. Two moulds, Aspergillus niger and Rhizopus stolonifer, were found associated with co-fermented meals of cassava and breadfruit. The sensory attributes of 100% breadfruit gari and co-processed gari samples were significantly different (p>0.05) from the control; the co-processed gari samples were however rated higher than the 100% breadfruit in terms of overall acceptability. All the gari samples retain their quality attributes during storage for six weeks, except for the gari sample with 100% breadfruit, which deteriorated after three weeks. This study established that 20% of breadfruit co-fermented with cassava yields a novel food product that compares favourably with 100% cassava gari in terms of microbial and sensory characteristics.