Abstract
The effect of water activity on the quality parameters
of cocona chips obtained by a combined osmotic dehydration
and hot air-drying method has been studied. Applying
the combined treatment resulted in a product with 0.055±
0.005 g water/g product in 4.3 h of drying. Although this
treatment caused a significant decrease (p<0.05) in the bioactive
compounds analyzed, the antioxidant activity of the samples
remained stable compared to fresh fruit. The applied treatment
permitted the development of a sweet, crispy snack with
acceptable optical and mechanical properties. To evaluate the
stability of the cocona chips during storage, the water sorption
behaviour (20 °C) and the relationship between the water content,
water activity and the glass transition were also studied.
Results showed that in order to ensure the functional quality
preservation of cocona chips during long-term storage and
avoid the crispness loss, the glassy state of the amorphous
matrix must be guaranteed.
