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Background: Tilapia (Oreochromis spp.) in the form of frozen fillets is one of the fishes with the highest commercial production levels worldwide. However, protein denaturation, membrane rupture, and lipid oxidation are commonly observed in fillets when stored at standard commercial freezing temperatures for long periods. This study proposes, for the first time, the use of maltodextrin and state diagrams to define processing strategies and suitable storage temperatures for fresh and dehydrated tilapia fillets. Differential scanning calorimetry (DSC) was used to study the effect of maltodextrin weight fractions (WMD) of 0, 0.4, and 0.8 on the thermal transitions of tilapia fillets as a function of solid mass fractions (Ws). Results: The glass transition temperature curve (Tgvs.Ws) and characteristic parameters of maximal freeze concentration (Tg′, Tm′, Ws′) of tilapia increased significantly with the addition of maltodextrin. Using developed state diagrams, freezing and storage temperatures of −22 °C, −15 °C, and −10 °C (P < 0.05) for long‐term preservation were defined for tilapia fillets produced with WMD of 0, 0.4, and 0.8. Conclusion: Maltodextrin is an excellent alternative as a cryoprotectant and drying aid to increase the thermal parameters of tilapia fillets by achieving frozen storage temperatures above the standard commercial freezing temperature of −18 °C. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Summary: Diagrams relating to water activity (aw), equilibrium moisture content (Xw) and glass transition temperature (Tg) are valuable tools for predicting amorphous fruit powders' storage procedure and stability. Thus, Tg–aw–Xw diagrams were constructed to characterise the amorphous state and define the critical values of water content (Xwc) and water activity (awc) of freeze‐dried juices of strawberry, pineapple, kiwi and prickly pear prepared with maltodextrin at the dry mass fraction (WMD) of 0, 0.4 and 0.8. The Tg and sorption data were fitted with a polynomial equation and the Guggenheim–Anderson–de Boer (GAB) model respectively. A Tukey test was performed to evaluate the difference between critical values of the powders (P < 0.05). The awc and Xwc increase with WMD and depend on the chemical composition of the powders. The highest critical values were found in pineapple powders, ranging from 0.174 to 0.632 and 0.029 to 0.142 dry basis (d.b.), and the lowest ones in kiwi juice powders ranging from 0.029 to 0.550 and 0.013 to 0.129 (d.b.). For WMD of 0.8, however, regardless of juice composition, stable powders in an amorphous state were obtained up to an aw of 0.52 at 25°C. [ABSTRACT FROM AUTHOR]