Extraction and characterisation of avocado seed starch (Persea americana Miller) and application in aerogels

Avocado seed (Persea americana Miller) is a by-product of fruit processing and is considered a potential alternative source of starch. The use of starches from unconventional sources can be an alternative to replace modified starches as a functional ingredient in food systems. This study aimed to extract and characterise starch from avocado seed varieties Fortuna and Hass and produce aerogels. Starches were characterised by physical, chemical, thermal and morphological properties. The aerogels were produced by physical crosslinking and evaluated for water absorption capacity and physical properties. The starch extraction yield was 12%, and the granules had oval and spherical morphology. Amylose content ranged from 41.95% to 49.46%, and relative crystallinity from 22% to 25% for Hass and Fortuna, respectively. The Fortuna starch showed higher pasting temperature, peak viscosity, peak time and final viscosity values. Aerogels had excellent structural characteristics and had not deformed after 24 h of hydration; the Fortuna starch aerogels showed higher water absorption and mechanical resistance. The properties of avocado seed starch indicate a vast potential for application in food industries and for developing biodegradable packaging with excellent physical properties and excellent water retention capacity.