Effect of Drying Methods on the Chemical and Storage Properties of ‘Daddawa’ Powder from Parkia biglobosa Seeds

Abstract

The study investigated effect of different drying methods on the chemical and storage properties of ‘daddawa’ powder produced from African locust bean (Parkia biglobosa) seeds. The study provided valuable insights into the drying methods that will help in optimizing the process of drying fermented ‘daddawa’ vis-à-vis nutritional and other quality properties of the product. The seeds were processed using slight modification of the traditional method. Fermented seeds were divided into four portions, three parts were dried using cabinet, oven and sun giving samples CB1, OC2 and SD3 respectively. Dried samples were comminuted using attrition mill and packaged. The fermented undried seeds (UA0 - control) was milled into paste and refrigerated before analysis. The samples were subjected to chemical analysis using standard procedures. Results of proximate composition revealed that moisture content of CB1 (13.04b±0.00), OC2 (12.64bc±0.47) and SD3 (12.03c±0.00) were within range of flour (10-14%). Protein content showed that SD3 (25.17a±0.09) was significantly (P<0.05) different to the rest samples. The result of vitamin content of ‘daddawa’ powder shows that SD3 (8.88a±0.00) was highest in vitamin B1 followed by UA0 (8.67a±0.15) with no significant (P<0.05) difference. The results show an array of mineral content including calcium, potassium, iron, magnesium, phosphorus, zinc, manganese and sodium. pH value was highest in OC2 (6.9) and SD3 (6.9) and least in CB1 (6.2). The study revealed that cabinet dried samples could be more stable owing to its lowered pH value and color thus proving its advantage over the others. Also, both water activity and microbial counts of bacteria and fungi increased with storage time. It is recommended that further studies should be carried out to determine the invitro and invivo digestibility of the protein for both the dried and undried (control) samples. Also, to ameliorate losses of nutrients during drying, lower temperature should be adopted.