Abstract:

Changes in the volatile flavor compounds of sturgeon caviar (Huso dauricused × sturger schrenckii) during cold
storage were analyzed by solid phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GCMS)
through NIST 05a.L mass spectral library search and alignment. Stugeon caviar was divided into four groups including
control group (with no additives), group A1 (with 0.5‰ potassium sorbate and 0.2‰ ascorbate), group A2 (with 0.5‰
potassium sorbate, 0.2‰ ascorbate and 0.2‰ nisin), and group A3 (with 0.5‰ potassium sorbate, 0.2‰ ascorbate and 0.2‰
L-ascorbyl palmitate). A total of 46 volatile compounds were identified in fresh sturgeon caviar. The compounds responsible
for the flavor of sturgeon carviar were mostly aldehydes, among which, hexanal, heptanal, octanal, and nonanal showed
higher levels. In addition, the unique lemony and woody aroma of fresh caviar may contribute to D-linonene, longifolene and
caryophyllene. The loss of volatile flavor compounds in sturgeon caviar was prevented by additive treatments in the present
study, and the levels of ketones and alcohols were decreased as well. The reduction reaction of aldehydes was promoted in
caviars by the addition of 0.5‰ potassium sorbate, 0.2‰ ascorbate and 0.2‰ nisin, thus leading to a substantial decrease
in aldehydes and a notable increase in esters. Finally, the changes in aldehydes caused by A1 and A3 treatments were
responsible for a stronger fishy and grassy smell of sturgeon caviar.

Key words: sturgeon caviar, solid phase micro-extraction (SPME), gas chromatography-mass spectrometry (GC-MS), volatiles flavor compounds