Effects of packaging material on microbial load and safety of ready–to-eat Voandzeia subterranean cake (Okpa)

Abstract

Background: Food-borne diseases remain a big challenge to food regulatory agencies. This study evaluated the microbiological safety of Voandzeia subterranean cake also called Bambara groundnut cake (BGC) packaged with cellophane and banana leaves. Methodology: Twelve samples, 6 packaged in cellophane and 6 packaged in banana leaves were randomly selected from 6 strategic locations including, Government House Area (GHA), Eke- Awka market (EAM), UNIZIK junction (UZJ), Aroma junction (ARJ), and Nwagu junction, Agulu (NWJ). Two other samples were prepared fresh at School of Pharmacy, Agulu (SOP) which served as control. All samples were analyzed for total aerobic and fungi counts. Antimicrobial susceptibility evaluation was done on the isolates to determine their antibiogram. Results: Microbial load of V. subterranean cake packaged in cellophane and banana leaves at 24 h post-preparation were <104 CFU.g-1 which is within safe limit of consumption. However, all samples packaged with banana leaves exhibited heavy contaminations with microbes at 48 h (above 105 CFU.g-1). Conversely, there were no growths of fungi in samples packaged with cellophane. The organisms: Micrococcus spp, Escherichia coli, Lactobacillus spp, S. aureus and Salmonella spp were found as contaminant. All the bacterial isolates were resistant to Co-amoxiclav and Cloxacillin. Salmonella spp isolates were resistant to all the antibiotics tested. Only the E. coli isolates had a Multi-Antibiotic Resistance Index (MARI) of less than 30%. Conclusion: The BGC packaged with cellophane are within the acceptable microbiological standard within the first day of production and compared better, microbiologically, than those packaged with banana leaves. However, the isolation of E. coli and Salmonella spp from the products questions the safety of the products and could spread Multi-Antibiotic Resistant isolates. From this study, good sanitary condition is recommended during preparation and packaging processes of V. subterranean cake with banana leaves.