Alginate/guacamole edible films as moisture barrier layers in multicomponent foods

In multicomponent foods having both moist and dry components (e.g., pizzas and tacos), moisture migration between components causes undesirable texture changes (e.g., loss of crispiness of the dry component). In this study, different proportions of alginate (film matrix), guacamole (hydrophobic component with sensory appeal), and glycerol (plasticizer) were combined to form edible films to be used as a moisture barrier between moist and dry components of multicomponent foods. Alginate was the component that most contributed to increase the film strength and to reduce its water vapor permeability (WVP). Guacamole, due to the presence of avocado lipids, enhanced the film hydrophobicity, although not having decreased the WVP (as expected), since it promoted discontinuities in the alginate structure. The film with the lowest WVP (containing an alginate/guacamole/glycerol dry mass ratio of 25/60/15) was inserted between nachos and tomato sauce, being able to reduce the crispiness loss of nachos during a 50-min storage.