EFFECT OF STORAGE ON MICROBIAL AND SENSORY QUALITIES OF PACKAGED YAM-CASSAVA “POUNDO” FLOUR

Abstract

Microbial load and Sensory quality of packaged yam-cassava poundo flour during storage were studied. Yam flour (YF) and cassava flour (CF) were mixed at different proportions to produce yam-cassava poundo flour and packaged using High Density Polyethylene (HDPE) and Polypropylene sack (PP) respectively. The samples were HDPE 100%YF, HDPE 90%YF: 10%CF, HDPE 85%YF: 15%CF, HDPE 80%YF: 20%CF and 100%YF, 90%YF: 10%CF, 85%YF: 15%CF and 80%YF: 20%CF. The samples were stored at ambient temperature (32 ± 2 o C) and relative humidity (76 ± 3%) for 24 weeks and were subjected to microbiological and sensory tests at 4 weeks interval. Results showed that the total plate count of sample (80% YF: 20 %CF ) packaged in HDPE was the lowest (4.9 x 10 4 cfu /g) while that of sample (100% YF) packaged in PP was the highest (9.4 x 10 4 cfu /g) at the end of the storage period. Fungal counts increased in all the packaged samples, as storage period increased. The lowest fungal counts (3.7 x 10 4 sfu/g) were recorded in HDPE 80%YF: 20%CF, this is significantly different (p<0.05) from the value obtained in PP 100% YF which was the highest fungal counts obtained (9.6 x 10 4 sfu/g). A bacterial species (Bacillus subtilis ) and two fungal species (Aspergillus niger and Fusarium solani ) were isolated and enumerated. Data obtained from sensory test (colour, aroma, texture and overall acceptability) decreased throughout the storage period but 80%YF: 20 %CF packaged in HDPE was more acceptable. The findings of this study indicate that yam-cassava poundo flour from the blend of 80%YF: 20 %CF packaged in HDPE is less susceptible to microbes and more acceptable in terms of sensory qualities during a storage period of 24 weeks.