Rheological properties of banana fruit in the creep test: Effect of variety and ripeness level

Banana quality is influenced by many factors, including variety and level of fruit ripeness. This quality can be evaluated from various points of view, one of which is the rheological consideration. Rheological properties are very important to study because they determine the design of equipment and processes, and minimise product damage. The aim of this research was to analyse and model the effect of variety and ripeness level on the rheological properties of banana fruit by applying a creep test. This research was carried out using a factorial experimental design 3 × 3 with 5 replications. Three varieties of banana, namely Ambon (Musa parasidiaca var. sapientum L. Kunt.), Raja (Musa parasidiaca L.), and Kepok (Musa acuminata balbisiana Colla) and each in three levels of ripeness, namely mature green, half ripe, and ripe. It was found that the parameters of the rheological properties of bananas changed according to the ripeness level (P < 0.05). The values of these rheological parameters decreased as the bananas ripened. Meanwhile, the variety and the interaction between variety and ripeness had no significant influence on the rheological parameters measured (P > 0.05). The constants of the four-element Burger model changed with the ripeness in all banana varieties. The Burger model with four elements could accurately predict the strain value of bananas tested in the creep test.