Synthesis, structural and functional characterization of ultrasonic-assisted OSA modified tamarind seed gum

• The tamarind seed gum (TSG) was successfully extracted and modified • Octenyl succinic anhydride (OSA) and ultrasonic-assisted-OSA modification methods were used • Ultrasonic treatment enhanced OSA's chemical reactivity towards the gum • Ultrasonic-assisted OSA-TSG exhibited superior functional properties Tamarind seeds are valuable yet underutilized biomass with significant potential for various practical applications. This study focuses on extracting the tamarind seed gum (TSG) and modifying it to develop a functional gum. Two modification methods were employed: treartment with 3 % Octenyl succinic anhydride (OSA) and ultrasonic-assisted OSA modification (20 KHz with power of 600W for 60 min), resulting in TSG OSA and TSG OSA-US , respectively. The modified gums were characterized based on their structural and physicochemical properties. The degree of substitution indicated that ultrasonic treatment enhanced the OSA chemical reactivity toward the gum. FTIR analysis confirmed that primary constituent of TSG is xyloglucans while the spectra of TSG OSA and TSG OSA-US verified the conjugation of TSG with OSA. Later, SEM results revealed the formation of surface pores due to OSA modification. Significant variations were observed in moisture content and pH while an antagonistic effect was noted in the color of modified TSGs. Among the samples, TSG OSA-US exhibited the highest swelling index (82.93 %), water holding capacity (17.30 %) and oil holding capacity (1.37 %). After this, emulsions were prepared with TSG OSA-US demonstrating the highest emulsifying capacity (100 %) and stability (87.10 %). In conclusion, the tamarind seeds biomass was effectively modified to enhance its functional properties, highlighting its potential for broader industrial and commercial applications.