Morphological and Molecular Studies of Banana Starch

Molecular and morphological characteristics of banana starch were determined by different spectroscopic techniques. Light and scanning electron microscopy showed the molecular order, shape and size of starch granules. Banana starch granules had a lenticular shape with an average size of 39 m. The X-ray diffraction study showed starch granules with a pattern of a mixture between the A- and B-type polymorphs, also referred to as C-type. The absorbance ratio (1045/1022cm 1) measured by infrared spectroscopy was 1.12, suggesting that the crystalline component was higher than the amorphous regions. Gelatinisation temperature assessed by differential scanning calorimetry was 77.6°C with a gelatinisation enthalpy of 23.4J/g. These data stated that banana starch had a high crystallinity level, which might be important in several food applications.