Nano-Chitin from White Leg Shrimp: Production by Acid Hydrolysis Combined with Ultra-sonic and Saltiness Enhancing Ability

Nano-Chitin is a nanometer-sized derivative of chitin. It is highly water-dispersible, positively charged, and biocompatible thus is considered to have potential applications in food, medicine, and environmental. This article presents a study on preparing Nano-Chitin from chitin for application in food technology, aiming to reduce salt content in food products. The Nano-Chitin was obtained from white leg shrimp chitin using acid hydrolysis combined with ultrasonic treatment. During hydrolysis, chitin powder was treated with 3.5N HCl at an acid-to-chitin ratio of 25:1 (mL/g). The reaction was carried out at 90°C for 120 minutes. After the reaction, the mixture was washed to remove residual acid, then subjected to ultrasonication at 77% amplitude for 34 minutes, using a solvent-to-solid ratio of 67:1 (mL/g). The ultrasonicated product was then freeze-dried to obtain Nano-Chitin. The resulting Nano-Chitin had an average particle size of 248 nm, a solubility of 73.1%, and a zeta potential of 24.5 mV. When added to a 0.65% NaCl solution at a concentration of 90 μg/mL, Nano-Chitin enhanced the perceived saltiness to a level similar to that of a 0.69% NaCl solution. Similarly, at 84 μg/mL, it increased the saltiness of a 0.61% NaCl solution to match that of a 0.65% solution. This enhancement in saltiness perception was observed at both 0.61% and 0.65% NaCl concentrations, which are commonly used in food. These results suggest that Nano-Chitin has potential as a tool for reducing sodium intake without compromising taste