Food Science and Technology (Campinas)
versão On-line ISSN 1678-457X
BRANDELERO, Renata Paula Herrera et al. Application of edible coatings in processed pineapples products by hurdle technology: desorption isotherms and kinetics of the osmotic dehydration. Ciênc. Tecnol. Aliment. [online]. 2005, vol.25, n.2, pp.285-290. ISSN 1678-457X. http://dx.doi.org/10.1590/S0101-20612005000200018.
The osmotic dehydration is an essential stage to manufacture fruit products by Hurdle Technology because it reduces the water activity to levels that, combined with one or more obstacles, increase the stability of the product. This process causes a loss of water from the fruit to solution and soluble solid incorporation by the product. This last flow is considered a disadvantage of the process because it can modify the product flavor. In this work, the action of alginate and gelatin edible coatings as a barrier to soluble solid incorporation during osmotic dehydration was studied. Pineapples with and without coating (control) were dehydrated in sucrose solution under isothermal conditions. The desorption isotherms of pineapples coated with gelatin, sodium alginate and without coating, as well as the kinetic parameters of the osmotic dehydration process were determined. Alginate coated pineapples presented minor solid incorporation without modifying the water loss flow when compared with the control.
Palavras-chave : gelatin; alginate; Halsey's equation.