Effect of microwave vacuum drying on nutritional composition of moringa (Moringa oleifera) leaves

Abstract

Moringa (Moringa Oleifera) is well known for its medicinal and functional food properties. Microwave vacuum drying is an assisted drying technology that aims to preserve the nutrients and improve overall product quality. In this study, different microwave power levels and vacuum on the nutrients and phytochemical constituents were investigated. Moringa leaves were procured and subjected to microwave vacuum drying at three different microwave power levels (90W, 270W and 450W) at 500 mm Hg vacuum pressure. The nutrients of the leaves were determined using standard analytical methods. Data were analysed and interpreted using one-way ANOVA. There was no significant difference in the moisture and fat content between the dried samples. Crude fibre content tends to decrease with the increase in power level, whereas protein and total carbohydrate content tend to increase with the power level. Highest TPC and DPPH radical scavenging activity were reported at 450 W microwave power level. The total colour difference, i.e., was least in the sample dried at 450W and high for samples dried at 90W.