The present work analyzes the application method and the effectiveness of edible coatings based on caseinates
or chitosan in partially dehydrated pineapple for its use in dry fruit–cereal products. Commercial
breakfast cereals and partially dehydrated pineapples prepared by osmotic dehydration and vacuum
impregnation were used for the experiments. Four coating application techniques, working at atmospheric
pressure or applying vacuum impregnation, were used for coating the pineapple samples. Coated
and uncoated samples were stored, at 20 C with breakfast cereals and were subsequently analyzed
weekly during 6 months. Critical water activity and critical water content for the glass transition of
the cereals at 20 C were estimated as 0.60 and 9.1 g water/100 g of product, respectively. Results show
that the application of coatings by vacuum impregnation and sample air drying after coating, considerably
extends the shelf-life of the pineapple–cereal system when caseinate based coatings are used. Chitosan
based coatings are less effective to limit water vapor transfer and the critical moisture content of
cereals are reached during the storage period.