Osmotic Dehydration with Alternative Humectants for the Production of Ultrachilled Cherry Tomatoes

The aim of the study was to explore and develop an innovative food category with distinct physicochemical properties (reduced water activity, aw ≤ 0.9) and a lower initial freezing point (IFP), in the range −10 °C to −8 °C, by integrating mild dehydration techniques (osmotic dehydration (OD)), with the scope of ensuring superior quality until final consumption. In this context, peeled cherry tomatoes were OD-treated at 35 °C for up to 180 min in hypertonic solutions, consisting of alternative humectants (maltitol, oligofructose, glycerol, glycine, alanine, and their combinations, as well as NaCl and CaCl2). Mass transfer (water loss (WL), solid gain (SG)), water activity (aw), IFP, and sensory properties’ changes were monitored during the osmotic process. The most effective osmotic solutions, regarding aw decrease, as well as IFP depression, were glycerol (50%), glycine (11%)–glycerol (39%) and alanine (7%)–glycerol (43%). aw and IFP of OD tomatoes (120 min −35 °C) significantly decreased (up to 0.9063 compared to 0.9778, and up to −7.55 °C) compared to −1.05° C of the untreated sample.