Biofilms from Hass avocado seed starch, its nanoparticles and xyloglucan

Currently, 7.2 Mt of avocados are produced annually worldwide. It represents between 11% and 16% of the weight of the fruit, is considered a waste, and can be a potential source of starch. This work focused on the elaboration of biofilms using Hass avocado seed starch, its nanoparticles, and a xyloglucan reinforcement in search of an alternative to plastic. The xyloglucan was extracted from tamarind seed, and the nanoparticles were synthesized from the starch using the acid hydrolysis method and ultrasound. Biofilms were developed into four different groups: starch alone (Group 1), starch + nanoparticles (Group 2), starch + xyloglucan (Group 3), and starch + xyloglucan + nanoparticles (Group 4). In each group three different concentrations were used. The biofilms were characterized according to thickness, water solubility, water vapor permeability, degradability, and mechanical properties (tensile strength, elongation at break, and elastic modulus). Strength and permeability improved 2.3 times and 35.02% with the inclusion of 1% nanoparticles and 2.2 times and 28.11% with 8% xyloglucan, respectively. Avocado seed has great potential as a source of starch and as a use for the synthesis of biopolymers that can eventually be taken to the industrial field.