Quality Attributes of Dried Osmo-Dehydrated Banana Slices Using Coconut Sugar and Sucrose as Osmotic Agents

Abstract

Dried fruits have gained more and more space in the food market. Osmotic dehydration (OD) can be applied as a pre-treatment to convective drying, aiming to produce foods with different characteristics. Therefore, the present study evaluated the OD process of banana slices using coconut sugar and sucrose, as well as its influence on convective drying (CD) and the physicochemical parameters of the product. Osmotic solutions at 40 and 60% were prepared, and OD was conducted at 30 and 50 °C. OD and CD kinetic parameters were analyzed. The dried product was characterized by moisture, water activity, shrinkage, texture, color, bioactive and volatile compounds. The higher concentration (60%) and higher temperature (50 °C) resulted in higher values of water loss, solid gain, and weight reduction during OD for both sugars. CD time varied between 225 and 345 min. OD as pre-treatment reduced drying time by up to 65%. The dried banana had low moisture content and low water activity. The shrinkage was up to 73.44%, associated with the higher concentration treatment and higher temperature during OD. OD reduced product hardness after CD. In general, using coconut sugar resulted in greater changes in color parameters and higher levels of bioactive compounds in dried bananas. Volatile compounds highly related to banana flavor were present after drying. Therefore, the use of coconut sugar as an alternative did not compromise the efficiency of the process and resulted in a product with some distinct characteristics compared to those obtained using sucrose.