Seasonal Variation of Biochemical Composition and Non-Volatile Taste Active Compounds in Pearl Oyster Pinctada fucata martensii from Two Selective Strains

Abstract

Recently, a new pearl oyster Pinctada fucata martensii strain has begun to be cultured as seafood. In the present study, the seasonal variation (February and June) in biochemical composition and flavor compounds in two P. f. martensii strains (strain for pearl production was abbreviated to PP, and seafood was abbreviated to PE) were detected to compare the nutritional and flavor differences between them, and to provide a reference for the seasonal preference of consumers for eating P. f. martensii. The ratio of soft tissues in PE-Feb was significantly higher than that in PP-Feb (p < 0.05). The contents of ash, crude protein, and crude lipid were higher in PP than those in PE in the same season, while significantly higher contents of glycogen in the PE strain were observed compared to the PP strain in the same season (p < 0.05). The major amino acids (such as Glu and Asp) and PUFA (such as DHA and EPA) were almost the same in two P. f. martensii strains in the same season, while the contents of these nutrients were significantly higher in February compared to June (p < 0.05). Taurine content in PE-Feb was the highest (19.58 mg/g wet weight), followed by PP-Jun, PP-Feb, and PE-Jun. The umami and sweet FAA contents of the same P. f. martensii strain in February were significantly higher than those in June (p < 0.05). The AMP content in PP-Jun was the highest (64.17 mg/100 g wet weight), followed by PP-Feb, PE-Jun, and PE-Feb. Succinic acid was the major organic acid, and its content in February was significantly higher than in June (p < 0.05). The betaine content in PP-Feb was the highest (23.02 mg/g of wet weight), followed by PE-Feb (20.43 mg/g of wet weight), PP-Jun (16.28 mg/g of wet weight), and PE-Jun (12.33 mg/g of wet weight), and significant differences were observed among these four groups (p < 0.05). In conclusion, the edible P. f. martensii strain harvest in February is rich in protein, glycogen, PUFA (DHA and EPA), taurine, succinic acid, and betaine, which could provide healthy nutrition and a good flavor for humans.