Abstract:
Grass carp was used as the raw material in this study to investigate the changes in the content of flavor nucleotides, free amino acids, and volatile compounds after treatment at various pressures (0.1, 100, 200, 300, 400, and 500 MPa for 10 min). The results showed that the content of adenosine monophosphate (AMP) in grass carp treated at 100, 400, or 500 MPa was increased significantly (p < 0.05), and decreased significantly after treatment at 200 or 300 MPa. Meanwhile, the content of inosine monophosphate (IMP) in the samples treated at 100 or 300 MPa was markedly improved, and was significantly reduced after the treatment at 200, 400, or 500 MPa. The effects of different pressures on free amino acids varied; treatment at 100, 300, and 400 MPa had a relatively small impact on the free amino acid content of grass carp, and the total free amino acid content of the samples treated at 200 or 500 MPa was decreased significantly. Among the six groups of samples, 32, 31, 35, 41, 44, and 40 types of volatile compounds were detected, respectively, and aldehydes, ketones and alcohols were the main compounds present. After ultra-high pressure (UHP) treatment, the relative content of alcohols was reduced, while the aldehyde and ketone content was increased significantly. Additionally, the number of aldehydes and ketones was increased when pressure exceeded 200 MPa.