Shelf Life Study and Quality Attributes of Cocoyam Chips

Abstract

The study was carried out to determine changes in the quality indices (levels of peroxides values, acid values, pH and colour) of cocoyam chips and microbiological safety (bacterial, yeast and mould counts) of cocoyam chips as influenced by temperature during storage period of fried cocoyam chips. Cocoyam tubers were processed into chips of 3mm thickness; the slices were then fried at a frying temperature of 170°C in a shallow pot for 7 minutes and was packaged in polyethylene bags and stored under room and refrigerator temperature. The results showed that there was significant difference (p≤0.05) between quality indices, microbiological safety and storage temperature and packaging materials. From week 0-5, peroxide values of samples stored under refrigeration temperature were found to be low, ranged from 3.39 - 11.58 meq kg-1, while the samples stored in the room temperature were found to be higher 3.81 - 12.87 meq kg-1. Acid values were also found to be low in the samples stored in the refrigerator, ranged from 5.79 - 16 3.34mg/g and the samples that were stored in the room temperature ranged from 9.94 - 24.05mg/g. The samples stored under refrigeration temperature had low bacterial counts ranged from 5.0 x 101 - 6.2 x 101 cfu/ml while samples stored in the room temperature had higher bacterial counts, ranged from 9.0 x 101 – 74 x 101 cfu/ml. Yeast and mould counts in samples stored under refrigeration temperature ranged from 4.0 x 101 - 32 x 10 cfu/ml while the samples that were stored in room temperature had higher counts, ranged from 3.0 x 10 – 38 x 10 cfu/ml. pH ranged between 6.88 - 7.02 for both samples during storage period. The results showed that storage temperature and properly sealed packaging material has effect on the above parameters that were determined. There were also colour changes during the storage period