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Hybrid mixture theory-based multiscale fluid transport equations were solved for drying of strawberries and carrots to predict the moisture transport during the process. The fluid transport equation was coupled with the selected product quality and nutritional attributes to predict changes in stress distribution, shrinkage, color parameters, and ascorbic acid/β-carotene content. The fluid transport equation includes a non-Fickian term that incorporates the effect of glass transition on moisture transport. A transformation between Eulerian and Lagrangian coordinates was used to include the moving volume effects due to shrinkage. Good agreements between the experimental and the predicted values of moisture content (RMSE ≤ 0.095, RMSE ≤ 0.579), color parameters (R2 ≥ 0.958, R2 ≥ 0.934), and volume changes (R2 ≥ 0.871, R2 ≥ 0.865) were obtained for strawberries and carrots, respectively. Drying in the vicinity of glass transition regime led to sharper moisture profiles, indicating non-Fickian transport. However, drying at temperatures higher than glass transition temperature of strawberries and carrots resulted in Fickian characteristics-round and smooth drying profiles for drying at 70 °C. Drying at higher temperature caused higher loss of quality attributes; it resulted in samples with lower color parameters and ascorbic acid or β-carotene content. Higher drying temperature resulted in greater shrinkage and deformation throughout the structure, leading to cracks and openings and faster degradation in quality attributes. The developed model would allow improving quality attributes and finding optimum processing conditions of strawberries and carrots. [ABSTRACT FROM AUTHOR]

Quality properties of concentrate pineapple juice obtained by block freeze crystallization (BFC) and evaporation technology are investigated. After three concentration cycles, the solutes were approximately 3.2 times compared to the initial condition and the final color was darker than that of the fresh juice. BFC allowed for higher bioactive compounds retention than evaporation in terms of total phenolic, flavonoid, and anthocyanin content. The cryoconcentrate juice showed a similar aromatic profile to the fresh juice, with 26 and 23 compounds, respectively. Conversely, only seven volatile compounds were identified in the evaporate sample. Finally, BFC is an effective technology to preserve important quality properties from fresh fruit juices such as color, polyphenols, and aromatic profile. [ABSTRACT FROM AUTHOR]