Processing parameters of oven and microwave drying on properties of ready-to-eat meal to heal (M2H)

Abstract

The increasing of natural disasters recently, are raising an awareness to develop a well-balanced with a longer shelf life of dried ready-to-eat meal to heal (M2H). During the natural disaster periods, the victims are lacking of basic nutrition due to inadequate food and clean water supply, leading to gradually weaken the body immune system. Drying operation conditions and methods are critical determinant in the preparation of instant or ready-to-eat meal rice because each parameter plays important role in achieving the desired quality. Therefore, the objective of this study was to investigate and analyse the effect of drying conditions of combined oven and microwave drying on the properties of M2H product. In this study, M2H was cooked by electric cooker for 20 min and then dried by combined oven and microwave drying method at various oven temperature (70 & 90 °C) and time (70, 130 and 180 min), and followed by drying in microwave at various power level (450 & 750 W) and time (1. 2, 3, 4 & 5 min). The results showed that the moisture content and rehydration capability of dried M2H increased with the increase of drying conditions of combined oven and microwave drying methods; moisture values reduced up to 5% dry wt. basis and maximum rehydration or water uptake was 56% after 5 min rehydration. In addition, there was gradually colour changes of M2H with the increased of colour difference (AE) in the range of 2.6 - 8.6. Combination oven and microwave drying with (90 °C, 130 min. 450 W. 4 min), (90 °C, 180 min, 450 W. 4 min) and (90 °C, 180 min, 750 W, 2 min) produced acceptable final product in term of moisture content, colour and with relatively fast rehydration capability. Each of the selected M2H samples had water activity (wa> ranged of 0.4- 0.5 which was less than the minimum requirement for a good microorganism growth. Proximate compositions of selected M2H were in range of 55.5 - 65.9% for carbohydrate, 6.4 - 9.3% for protein, 65.9 - 17.3% for fat and 3.4 - 3.5 for ash content. In conclusion, based on consumer's perspective by means of sensorial evaluation, dried M2H was found moderately acceptable emergency functional food products.