Volatile components change in prepared crisp grass carp (Ctenopharyngodon idellus) during chilling storage

In order to improve the quality of crisp grass carp (Ctenopharyngodon idellus) (CGC) fillets during chilling storage, the fillets were treated by the water extraction of perilla (Perilla frutescens). We analyzed the change in the volatile components of CGC fillets during chilling storage by solid phase micro-extraction (SPME) and gas chromatography-mass spectrometry (GC-MS). A total of 70 volatile components were identified. The results show that the relative contents of aldehydes and alcohols were higher than those of other volatile components. The aldehydes which play a major role in the flavor of CGC fillets increased at the beginning and then decreased during chilling storage. The relative content of aldehyde and (E,E) 2,4-decadienal reached the maximum value on the 8^th day, which were 15.84% and 6.07%, respectively, and then decreased continuously. The relative content of 1-octene-3-alcohol increased by 10.01% on the 16^th day, resulting in fishy odors aggravation. Moreover, the relative content of linalool decreased during chilling storage, and the overall effect on the flavor of fish also reduced gradually. Additionally, the relative content of ester decreased by 85.19% on the 16^th day and the influence on the flavor of fillets decreased gradually. After the 8-day chilling storage, the relative content of 2,3-octanedione was 8.77%, increasing by 4.56%. At the same time, the relative content of β-ionone decreased significantly with extension of chilling storage, and decreased by 95.87% on the 16^th day. However, β-ionone, which had special aroma and low threshold, contributed to the flavor of CGC fillets. Besides, the other kinds of volatile components were considered to have small effect on the flavor due to their high odor thresholds or low contents.