Effect of Storage Conditions (Relative Humidity, Packaging Materials and Time) on the Chemical Properties of Maize-soy Flour Blend
S. O. Akpapunam *
Department of Food Science and Technology, University of Agriculture, P.M.B. 2373, Makurdi, Nigeria.
J. K. Ikya
Department of Food Science and Technology, University of Agriculture, P.M.B. 2373, Makurdi, Nigeria.
D. I. Gernah
Department of Food Science and Technology, University of Agriculture, P.M.B. 2373, Makurdi, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Aims: The aim of this study was to examine the effect of storage conditions on the of maize-soy flour blend.
Study Design: Preliminary studies were conducted using ratio blends of 70:30, 75:25, 80:20, 85:15, 90:10, 95:5 and 100:0 of maize flour to soy flour. This was to ascertain the best blend formulation for the study. The sensory attributes showed that the ratio 85:15 of maize-soy flour blend was preferred. It was packaged in low density polyethylene (LDPE), high density polyethylene (HDPE) and stored at 30.5 ± 3°C with relative humidity of 57% and 82% for 4 months. Analysis of proximate composition, pH, total titratable acidity (TTA), thiobarbuturic acid (TBA) was carried out on the samples at a monthly interval respectively.
Results: Packaging significantly (p > 0.05) affected the chemical qualities of “soy-fermented maize” flour during storage. Moisture content, titratable acidity (TTA) and thiobarbuturic acid (TBA) increased with the storage period (9.46% - 23.5%, 0.12% - 0.21%, and 0.06 - 0.12 respectively) while all other chemical qualities of the soy-fermented maize flour decreased significantly (p > 0.05) (pH: 5.18 - 3.45, protein: 15.21% - 12.18% fat: 7.45% - 5.36%, fibre: 3.27% - 1.65%, ash: 1.12% - 0.89% and carbohydrate: 62.97% - 56.87%.
Conclusion: The samples packaged in HDPE were more acceptable than those in other packaging materials due to its considerable maintenance of the flour’s quality during and after storage.
Keywords: Storage, Agidi, maize-soy flour, low density polyethylene and high density polyethylene