Efficient recovery of high-solubility chitosan from shrimp shells: a step forward in marine waste utilization

This study aims to develop a low-energy method for extracting high-purity chitosan from shrimp shell waste. Grounded in the principles of waste valorization, the work addresses the need for alternatives to methods of chitosan extraction that rely on heat and generate significant energy costs. The methodology involved a room-temperature chemical process: deproteinization using sodium hydroxide and demineralization with hydrochloric acid. A notable innovation is the application of the xanthoproteic test—used here for the first time in this context—to monitor protein removal, thus enhancing process control. The extracted chitosan was characterized via FTIR spectroscopy, and its degree of deacetylation was assessed using titration and FTIR. Solubility in 1% acetic acid and moisture content were also measured. The results revealed a high degree of deacetylation and excellent solubility, confirming the efficiency of the mild process. This approach offers a pathway for converting marine biowaste into a high-value biopolymer.