Vol. 11, Issue 2 (2022)

Author(s):
P Geetha

Abstract:
The fresh moringa pods (Drumsticks) were dehydrated by microwave-assisted hot air drying (MAHD) and conventional hot air-drying methods. The samples were dried at three different temperatures, viz., 50 °C, 60 °C and 70 °C with and without the application of microwaves. Microwave power density of 1 W/g was used for the MAHD. The final moisture content was targeted as 13% wet basis. The quality attributes, namely colour, rehydration ratio, and volatile compounds were analysed and compared with that of the fresh moringa pods. The volatile compounds were analysed using z-Nose (an electronic nose) and bioactive molecules were analysed using gas chromatography–mass spectrometry. The results showed that the MAHD method had significantly (P< 0.05) reduced the loss of volatiles during drying. Also, MAHD preserved most of the bioactive molecules when compared to the conventional hot air-drying method. The samples dried at 50 °C using MAHD were the best in terms of all of the quality attributes tested in this study. Also, the results established that the z-Nose can be used as a quick and inexpensive means to assess the effect of different process parameters on the aromatic quality of the product and quantitatively classify quality based on aroma.