Identification of volatile compounds in Antarctic krill (Euphausia superba) using headspace solid-phase microextraction and GC-MS

Abstract

Antarctic krill (Euphausia superba) has a very high economic value due to its enormous production, higher protein content, and nutritional value. This study presents a detailed optimization of the analysis of volatile flavor compounds from Antarctic krill by combining headspace solid-phase microextraction (HS-SPME) as the extracting method and gas chromatography/mass spectrometry (GC-MS) as the analysis. An optimal solid-phase microextraction (SPME) fiber was selected, and the microextraction conditions were optimized using the response surface method (RSM). The Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS) fiber showed the highest extraction efficiency and was selected for further optimization of extraction temperature, extraction time, and sodium chloride concentration. Forty-two types of volatile substances producing characteristic flavors were detected, seven of which contributed significantly to the flavor of Antarctic krill. Ethers, pyrazine, and aldehyde compounds contribute to the main flavor of Antarctic krill. The compounds 2-ethyl-3, 5-dimethyl-pyrazine, 2, 3, 5-trimethyl-6-ethyl-pyrazine, and 3-ethyl-2, 5-dimethyl- pyrazine produce the roasted flavor and the characteristic nutty odor. Moreover (E, Z)-2, 6-nonadienal adds a cucumber fragrance. The compounds 3-methyl-butanal and 3-methional play an important role in determining the overall flavor.