Edible coatings for enhancing osmodehydration process of pears using glucose solution: a study on mass transfer kinetics and quality assessment

The present study aimed to evaluate the combined application of edible coatings (alginate or pectin) and the osmotic dehydration process (glucose solution at 40 degrees Brix and 60 degrees Brix, solution temperatures of 20 and 40 degrees C, and process times of 1, 2, 4, 8, and 16 h) on mass transfer kinetics and physicochemical parameters (weight reduction (WR), water loss (WL), solids gain (SG), and optical and mechanical properties) of pear cubes. The best dehydration performance was observed in the coated samples treated at 60 degrees Brix-40 degrees C. At the end of this process, the coated samples showed higher values of WR (77.30% and 75.13%) and WL (77.39%; 74.38%) and lower values of SG (1.69% and 1.24%) than the uncoated samples (WR: 65.97%, WL: 68.38%, and SG: 4.12%). Additionally, optimal retention of optical and mechanical properties was achieved in the coated samples exposed to the 40 degrees Brix-40 degrees C condition. This work provides relevant information about the application of edible coatings as an alternative for enhancing the osmodehydration process concerning dehydration performance, controlling the uptake of osmotic solids, and preserving the quality of minimally processed fruit and vegetable products. Highlights of the work include: Coated samples improved the dehydration performance under conditions of 60 degrees brix-40 degrees C; The coating enhaced the initial rate of moisture transfer; Pectin-coated samples showed the smallest colour difference at 40 degrees Brix-40 degrees C; Alginate-coated samples showed better preservation of mechanical properties at 40 degrees Brix-40 degrees C. image