Affiliations: [a] CIDCA (CONICET-CCT y Universidad Nacional de La Plata), 47 y 116, La Plata (1900), Argentina
| [b] Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina
| [c] Facultad de Ingeniería, Universidad Nacional de La Plata, 1 y 47, La Plata (1900), Argentina
Corresponding author: Prof. Laura Campañone, CIDCA (CONICET-CCT y Universidad Nacional de La Plata), 47 y 116, La Plata (1900), Argentina. Tel.: +54 221 4890741; E-mail: [email protected].
Abstract: BACKGROUND:The use of polysaccharide based edible coatings as a barrier against the solute entry of high caloric constituents, such as sucrose, is a suitable strategy to develop pro-healthy osmo-dehydrated products. OBJECTIVE:This work aims to study the effect of a calcium alginate film over the drying kinetics of strawberries during an osmotic dehydration (OD) treatment at 60°Brix, 4 h, 40°C (sucrose). Also, textural parameters were evaluated. METHODS:It was determined the changes in some selected physical properties, such as: moisture, total solid contents, one-dimensional shrinkage and texture, at 30 min steps during OD treatment. Besides, water and solid diffusion coefficients (
, respectively) were calculated by using the analytical solution of Fick’s equation. RESULTS:Diffusion coefficients for water and solids showed significant differences due to coating presence as an evidence of the barrier effect. Coated strawberry samples presented several changes after 2 h of OD treatment at the assayed conditions for most of the parameters evaluated. CONCLUSIONS:Alginate coating at the tested conditions acts as a barrier to sucrose influx and to water outflux until 2 and 3 h of OD treatment, respectively. Besides, a good textural quality for osmotically-dehydrated strawberries was obtained.