PROCESSING AND SHELF – LIFE EXTENSION OF GARRI USING CHITOSAN AS A PRESERVATIVE
U. OKORONKWO CHRISTOPHER *
Department of Food Science and Technology, Abia State University, Uturu, Nigeria.
UNEGBU VALENTINE
Department of Microbiology, Spiritan University, Nneochi, Abia State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Garri, a product of cassava was produced under a controlled condition and preserved with different levels of chitosan. The proximate composition and effect of chitosan on microorganisms were investigated at the different stages during storage, using traditional approach. Results of garri mash treated with chitosan before toasting showed an percentage composition of fibre and carbohydrate contents increasing with decreased percentage moisture, ash, protein and fat decreased during storage. Samples treated with chitosan after toasting showed a percentage increase in fibre and ash, then percentage decrease were observed in moisture, fat, protein and carbohydrate respectively. Chitosan inclusion was found to exhibit antibacterial and antifungal effect on different garri samples in a concentration dependent manner. Microbial isolates identified includes Bacillus spp, Staphylococcus spp, Pseudomonas spp, Proteus spp, Aspergillus spp, Penicillin spp, Candida spp, Fusarium spp respectively. Chitosan inclusion brought about marked percentage reduction in the number of organisms present during the four (4) weeks of storage. Fusarium spp showed a steady increase in growth with increased storage time. Our findings suggest that chitosan inclusion in cassava mash at regulated concentrations could support large-scale garri processing even at the subsistent level with reduced spoilage.
Keywords: Cassava, fibre, microbes, chitosan, antimicrobial, storage