EFFECT OF DRYING METHODS AND EXTRACTION TIME-TEMPERATURE REGIME ON MANGO KERNEL LIPIDS

In this study, effect of drying method and time temperature regime of extraction on quality of mango kernel lipid was evaluated. Hot air drying required drying of seeds for long intervals and exposure to higher temperature, where as microwave drying was found to be quick due to heating induced at the molecular level. The drying time under optimized conditions for microwave was reduced by 34 folds when compared with hot air drying. Parameters including drying temperature, extraction time, lipid yield and fatty acid profile were evaluated. The study shows that modification of extraction method for lower temperature and lesser time does not alter the quality and quantity of lipids from mango kernel (10.8%). Structural changes induced due to drying were studied using scanning electron microscopy. Statistical analysis showed that drying conditions and extraction conditions affected the lipid yield. The further comparison between two methods was done in terms of fatty acid profiles and oxidative stability. The stability of lipid was estimated by measuring the ratio of linoleic acid to palmitic acid for all extraction conditions. The ratio of C18:2/C16 was similar for microwave irradiation when compared to hot air dried samples (1.0 - 1.2). It was concluded that mild microwave power level (180W) helps in quick drying of kernels. The structure was found to be intact with minimal damage to starch granules. Lower microwave power level helped in retention of the lipid yield and quality while higher microwave power levels significantly affected the unsaturated fatty acids.