Comparison of the effect of microwave freeze drying and microwave vacuum drying upon the process and quality characteristics of potato/banana re‐structured chips

Abstract

This study investigated the drying characteristics of microwave freeze-drying (MFD) ⁄ microwave vacuum drying (MVD) of banana ⁄ potato restructured chips of varying proportion and microwave power. The results showed the MFD drying time had a maximum one-hour time difference between the samples treated with 2 W g )1 and 3 W g )1 microwave power; and the higher potato content samples have about 30 min predominance than low potato content samples in drying time and the total drying time of MVD samples was less than 60 min. For the rehydration ratio, MFD samples were far superior to the MVD samples. The MFD samples had more than 4.5 rehydration ratio. The data of the colour difference metre showed that 3 W g )1 microwave power would make samples slightly charred. The biggest differences between the MFD and MVD chips lie in their texture and shape; the hardness of MVD samples was 30.86 N, thrice higher than MFD samples.

Novel Combined Freeze-Drying and Instant Controlled Pressure Drop Drying for Restructured Carrot-Potato Chips: Optimized by Response Surface Method

“…of the partially dried product, and equilibrium temperature of 90 ∘ C, respectively. This was in accordance with the results of Jiang et al [30] who reported that higher crispness of the dried products was obtained by adding higher amount of potato in the sample. In Table 3, the interaction terms of all the process parameters showed significantly negative effects ( < 0.01), while the linear terms and quadratic terms of all the process parameters exhibited no significance on hardness.…”

Drying of restructured chips made from the old stalks of Asparagus officinalis : impact of different drying methods

“…This was probably due to the lowered water content resulting in a decrease in the dielectric constant ϵ ′ and dielectric loss factor ϵ ″. Also, the final drying stage involves removal of sorbed water, and this period can be as long as or longer than the time required for the removal of free water in the initial drying stage . Similar results were found by Mothibe et al At the same microwave power level, the drying time required to achieve the desired moisture content for PSMVD was longer than that in MVD, which was probably due to the fact that the second drying stage with pulsed‐spouted flushing air resulted in destruction of the vacuum environment and loss of heat in PSMVD.…”

Production of Crispy Granules of Fish: A Comparative Study of Alternate Drying Techniques

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