Measurement of physicochemical and thermophysical properties of banana (Var. Barlin) using the unsteady state method

Banana is a variety that is not widely utilized because it is easily spoiled and less attractive to consumers. In addition, bananas are rich in nutrients and minerals that are good for human health. The handling and processing of banana-based materials are the reference data for physicochemical and thermophysical properties. The thermal properties of banana (var. barlin) are fundamental to know as a parameter to estimate the heat transfer of materials in the drying process. The purpose of this study was to determine the thermal conductivity and physicochemical properties of the banana in maturity levels (1 to 4). The thermal conductivity was measured as exocarp, mesocarp, and paste at 70°C, using the unsteady state method with a numerical approach. The geometric physical properties of banana showed a decrease in mass (40.43-43.42g), length (87.75-89.97mm), outside diameter (28.75-30.38mm), inside diameter (27.86-28.39mm), and peel thickness (0.88-1.99mm). Physicochemical properties increased with the maturity of bananas, i.e. water content (76.97-81.33%wb), Brix (8.50-25.10 %), the estimated value of alcohol content (4.32-15.00), bulk density (673.49-1144kg/m3), L∗ (73.74-79.20), a∗ (-19.43 to -3.52), b∗ (33.35-48.39). However, the texture profile decreased with maturity, i.e., hardness (26.4-200.2g), gumminess (16.3-160.5g), and chewiness (9.8-154.1g). The results indicated that the paste had the highest thermal diffusivity and thermal conductivity, i.e., 1.6x10-5-2.3x10-5 m2/s and 0.02-0.04W/m.°C, respectively.