Microbiological, nutritional and sensory evaluation of snack bars developed using Bambara groundnut (Vigna subterranean L.) and maize (Zea mays)

Abstract

Over the years, snacking has become a regular habit for majority of the population with increasing need for food manufacturers to meet consumers’ demand through product development. In this study, snack bars were prepared using maize and Bambara nuts mixed in the following ratios: A, 100% maize; B, 100% Bambara nuts; C, 50% maize: 50% Bambara nuts; D, 75% maize: 25% Bambara nuts; E, 75% Bambara nuts: 25% maize. The total heterotrophic bacterial count of samples A to E was within the limit stipulated by International Commission on Microbiological Specification for Food. The frequency of occurrence of bacterial isolates from the samples include Bacillus species (24%), Staphylococcus species (24%), Lactobacillus species (24%), Escherichia coli (19%) and Serratia species (9%), while the fungal isolates include Aspergillus (33%), Penicillium (27%), Rhizopus (20%) and Saccharomyces species (20%). The moisture, ash, carbohydrate, crude protein, fat and fiber content of the samples were within the range of 11.47±0.99-17.45±1.01, 1.09±0.07-2.00±0.15, 56.05±0.65-70.37±0.71, 6.32±0.36-15.00±0.22, 4.60±0.50-7.00±0.30 and 2.60±0.25-3.10±0.31%, respectively. There was a significant difference (p<0.05) in the proximate composition among the samples except for crude fiber. The calorie value range between 347.20-367.69 kcal and acceptability of the samples compared favourably with a commercialized snack bar.