Optimization of ultrasonic-assisted extraction of flavor compounds from shrimp by-products and characterization of flavor profile of the extract

•White shrimp heads (WSHs) are utilized for the extraction of flavor compounds.•Ultrasonic-assisted extraction increased the content of umami compounds.•Ultrasonic extract of WSHs is used to develop shrimp flavor concentrate (SFC). This study aimed to optimize the ultrasonic-assisted extraction conditions of flavor compounds from white shrimp heads (WSHs). The effects of sonication amplitude, sonication time, and solvent-to-solid ratio on the extraction yield (EY) of flavor compounds and the degree of protein modification (DPM) were evaluated by Box-Behnken design and response surface methodology (RSM). The optimum EY (40.87 %) and DPM (26.28 %) were obtained at amplitude, time, and solvent-to-solid ratios of 63.2 %, 20.5 min, and 20.8 mL/g, respectively. The optimum DPM value indicates that sonication markedly influenced the protein denaturation, as evidenced by the higher TCA soluble protein content. Further, we also investigated the taste active composition of ultrasonic extract of shrimp head (USH). Results show that the equivalent umami concentration (EUC) value was significantly (p