Effect of skimmed milk and vegetable powders on shelf stability of millet‐based composite flour

BACKGROUND: Millet porridge is a major complementary food used in Uganda but it is limited in protein and micronutrients such as zinc and beta‐carotene. Addition of milk and vegetable powders are known to greatly improve the nutrient content of millet flour. However, there was limited information on the shelf stability of the resultant composite flour. This study aimed at assessing the effect of milk and vegetable powders on the shelf stability of millet‐based composite flour. RESULTS: There was a general increase in the moisture content, peroxide value (PV), free fatty acids (FFA), thiobaturic acid (TBA) and total plate count (TPC) of both composite and millet flours over the eight weeks storage period. However, higher moisture content, PV, FFA, TBA and TPC values were recorded in the composite flour compared to millet flour (control) at each sampling interval. Sensory evaluation results revealed that panelists preferred porridges prepared from millet only compared to those from composite flour. The degree of liking of porridges from both composite and millet flours generally decreased over the storage period. However, both porridges were deemed as acceptable by the end of the storage period. The TPC also remained below 10(5) cfu g(−1) which is the maximum limit recommended by the Uganda National Bureau of Standards (UNBS). CONCLUSION: The study findings indicated that the addition of milk and vegetable powders negatively affected the stability of the composite flour. We recommend further studies to stabilize the product during storage. © 2018 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.