Improving the drying kinetics and microstructure of vacuum‐fried ripened durian chips

Abstract

SummaryThis research evaluated the effects of process conditions on the physiochemical properties of vacuum‐fried durian chips. Ripened durians were sliced and fried at 90, 100, 110 and 120°C under 8‐kPa absolute pressure. From this study, microwave heating (MWH) during vacuum frying (VF) significantly reduced the frying time by 20% compared to VF (P < 0.05) with the effective moisture diffusivity for VF, pre‐treatment before vacuum frying (P+VF) and VF+MWH at 110°C determined to be 3.63 × 10−09, 4.30 × 10−09 and 4.84 × 10−09 m2 s−1, respectively. VF+MWH produced chips with significantly lower shrinkage, more yellowness (P < 0.05) and higher crispiness (consistent with the microstructure from scanning electron microscopy (SEM)). In addition, VF+MWH drastically decreased oil absorption by 10%, while P+VF yielded the lowest specific energy consumption (SEC). From sensory evaluation, the overall acceptability of VF+MWH chips rose from 5.83 to 6.07 (seven‐point hedonic scale), thus making the product fall into the ‘Good’ to ‘Very Good’ range.