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Summary The impact of different pretreatment methods [high pressure (HP), high‐intensity electric field pulses and freezing], osmotic solutions (sucrose, glucose and salt–sucrose mix) and osmotic conditions (atmospheric pressure, vacuum and ultrasound treatment) on the mass transfer of strawberry halves during osmotic dehydration (OD) and on some physical characteristics (leaching of cell constituents, colour and texture), were investigated. Highest water loss was obtained in samples treated under vacuum, in a salt–sucrose mix or under HP or in a high‐intensity electric field. The increase in solid gain relative to untreated samples was 96–270% for the prefrozen treatment, 40–160% for high pressure and 50–62% for high‐intensity electric field treatments. OD under vacuum and the use of glucose solutions facilitated greater solid gain. Leaching of cell constituents was high in prefrozen samples, leading to greater change in product colour and softer texture compared with other pretreatments. Although OD under ultrasound treatment enhanced mass transfer, its overall influence was not significant (P > 0.05) compared with atmospheric pressure.

As a result of the increasing consumer demand for minimally-processed fresh-like food products with high sensory and nutritional qualities, there is a growing interest in non-thermal processes for food processing and preservation. Key advanced technologies such as high-pressure processing, pulsed electric fields, dense gases and ultrasound are being applied to develop gentle but targeted processes to further improve the quality and safety of processed foods. These technologies also offer the potential for improving existing processes as well as for developing new process options. Furthermore, by adding new process dimensions (such as hydrostatic pressure, electric fields, ultrasonics, supercritical CO2) to the conventional process variables of temperature and time, they facilitate enlargement of the availability of unit operations. These operations might be applied effectively in unique combination processes, or as subsequent processing tools in more-targeted and subsequently less-intensive processes for food preservation and modification than the currently-applied processes.