Analysis of the Shelf Life of Soya Bean (Glycine max) Flour

Aim: This work was to investigate the shelf life of fresh and stored soybean flour by isolating resident bacteria and carrying out their proximate analyses.

Place and Duration of study: Samples were bought from Roundabout market at Iwo, Osun state, Nigeria. An analysis was carried out within 8 month.

Methodology: The bacteria were isolated and identified using standard morphological and biochemical tests. The antibiotic susceptibility of the isolated bacteria was also carried out using standard methods.

Results: Isolated bacteria belonged to genera Staphylococcus, Bacillus, Escherichia and Enterobacter. The number of isolated organisms was higher in all cases in the stored flour sample. The results showed that the percentage of crude protein (37.0 ± 0.12), crude fat (16.4 ± 0.04) and dry matter (91.1 ± 0.06), was highest in the freshly purchased soybean flour. The moisture content of the stored flour was (9.1 0. ± 06), while carbohydrate (35.2%), ash (3.9 ± 0.04) and crude fibre (4.2 ± 0.02) were also higher. Resistance to antibiotics was highest to cloxacillin (100%), amoxicillin (75%) and augmentin (75%).

Conclusion: The result of this work showed that long term storage is detrimental to the soybean flour and the presences of antibiotic resistant bacteria have serious public health implications.