Determination of key volatile fishy substances of sea cucumber powder during the processing and their removal by supercritical fluid extraction

Abstract

More than 40 volatile compounds were detected in sea cucumber powder during the processing (through freeze-dried, desalination, supercritical fluid extraction and ultra-micro grinding) by multiple methods including e-nose, GC-IMS and GC–MS. It has been determined that aldehydes are the predominant volatile substances in the original freeze-dried sample, accounting for about 30 % of the total volatile substances. In addition, we established a supercritical fluid extraction strategy that could efficiently remove the aldehydes from the sea cucumber powder. GC-IMS and GC–MS showed that the relative content of aldehydes significantly decreased by 14 % and 28 %, respectively. Quantification of aldehydes using GC–MS showed a significant decrease in octanal from 927 µg/kg to 159 µg/kg. Further investigation combined with OAV analysis showed that 17 volatile substances in the freeze-dried sea cucumber powder were considered to be the predominant volatile compounds (OAV > 1).The primary fishy compounds found in sea cucumber powder were identified as hexanal, octanal, and an unidentified compound using GC-O, which can be effectively removed (OAV can’t been estimated) by the supercritical fluid extraction strategy we established.