Influence of high intensity electric field pulses and osmotic dehydration on the rehydration characteristics of apple slices at different temperatures

Abstract This study aimed to investigate the influence of pre-drying treatments (high intensity electric field pulses (HELP) with 20 pulses having 48 J/kg for 400 μs per pulse and osmotic dehydration (OD) in 50% sucrose solution) on some characteristics of rehydrated apples at different temperatures (24–90°C). Rehydration rate increased with temperature but higher rehydration capacity (RC) values were obtained at low temperatures (24°C and 45°C). RC of HELP treated + OD samples was 10–30% higher than the RC of the untreated + OD samples. Solid retention after rehydration was highest in HELP treated samples which also had firmer texture at full rehydration. Sugar gained during OD increased product firmness. Electrolyte release during rehydration was temperature dependent. The colour of the rehydrated apples darkened with increase in rehydration temperature and/or time.

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