LAUSR

Abstract In this contribution, we report on the characterization of starch nanoparticles (SNP) extracted from breadfruit by high-intensity ultrasound. These biocolloids were characterized regarding their spectroscopic, morphological, rheological, and thermal properties in addition to ζ potential, light transmission, and X-ray diffraction (XRD) measurements. After submitting a 0.5 % (w/v) aqueous suspension to 75 min of ultrasound treatment, particles of ca. 145 nm in diameter were obtained. The relatively low ζ potential (ca. −17 mV) did not prevent SNP aggregation. This was corroborated by transmission electron microscopy images. The viscosity of SNP suspension (2.7 mPa s) was lower than that of native breadfruit starch (4.2 mPa s). Thermogravimetry indicated that SNP were more thermally unstable than native starch. Infrared spectroscopy indicated that C O groups were the most weakened by the ultrasound treatment. XRD revealed the rupture of the crystalline structure of native starch, providing SNP with an amorphous character. Altogether, this set of characterization techniques demonstrates the feasibility of producing SNP in a rapid fashion and in the absence of chemical modifications, characteristics that are in line with the contemporary trends towards greener products and processes. The SNP produced herein through a mechanochemical approach have enormous potential for colloidal-related applications, including food, cosmetic, pharmaceutical, and biomedical systems.