Morphological, structural, thermal properties of a native starch obtained from babassu mesocarp for food packaging application

Abstract

Growing demands for the use of biodegradable polymer films in food packaging have led to studies on several sources of non-conventional starches. Corn starch (CS), is the most investigated starch source for food packaging due to its abundance and stability under processing and manufacturing conditions. Other sources of starch such as rice, potatoes and cassava have also been investigated and, more recently, babassu mesocarp starch (BMS), native to Northeastern Brazil, has been explored for its innovative potential in the manufacture of biodegradable films. In this work is we have extracted and characterized the starch contained in babassu mesocarp and to compared its morphology, structure, thermal stability and viability for polymer film manufacturing with that of commercial corn starch. Our data showed babassu mesocarp native starch granules to have an oval shape and to display flaking and fractured surfaces while corn starch granules exhibited polygonal shapes with smooth surfaces and without aggregates. XRD analysis revealed two different types of crystalline forms for both starches. Although babassu starch is less thermally stable than commercial corn starch, both starches have similar characteristics and it is believed that babassu mesocarp starch can be used as new renewable and biodegradable resource for food packaging applications.