The identification of three phospholipid species roles on the aroma formation of hot-air-dried shrimp (Litopenaeus vannamei) by gas chromatography–ion mobility spectrometry and gas chromatography- mass spectrometry

Aroma is critical to the commercial acceptance of the hot-air-dried shrimp. The purpose of this study was to investigate the effect of phospholipid species with different fatty acid compositions on the aroma formation of dried shrimp. GC-IMS and GC–MS were used to obtain volatile fingerprints and volatile compound profiles, respectively. The results of GC-IMS and GC–MS indicated that the effect of phospholipids on the overall aroma of dried shrimp was related to the unsaturation of fatty acids constituting phospholipids, and fatty acids with higher unsaturation had a greater impact on the overall aroma of dried shrimp. Therefore, PC(C16:0/C18:2) had the greatest effect on the overall aroma of dried shrimp, followed by PE(C18:1/C18:1), and the lowest was PE(C18:0/C18:0). GC–MS results showed that phospholipids could promote the formation of aromatic compounds such as pyrazines and aldehydes in dried shrimp, and the magnitude of the effect of different phospholipids was highly positively correlated with the degree of unsaturation of fatty acids in phospholipids. PE(C18:0/C18:0) could significantly promote the formation of 2,3,5-trimethylpyrazine and 2-ethyl-3,5-dimethylpyrazine. PE(C18:1/C18:1) could importantly improve the formation of 2,5-dimethylpyrazine, 2-ethyl-5-methylpyrazine and 1-octen-3-ol. PC(C16:0/C18:2) could prominently increase the formation of 2,5-dimethylpyrazine, 2,3,5-trimethylpyrazine, 2-ethyl-5-methylpyrazine, 2-ethyl-3,6-dimethylpyrazine, benzaldehyde and 2-nonanone. Furthermore, three phospholipid species significantly inhibited the formation of trimethylamine.