Comparison Of Quality And Nutrient In Muscles Of Wild, Pond And Factory Cultured Paralichthys Olivaceus

A comparative study was conducted to investigate the morphological and nutritional diversity of commercial size Paralichthys olivaceus which grew in three kinds of growth pattern, including wild(W), pond(P) and factory(F) cultured. The current study is aiming to investigate the effect of different growth patterns on nutritional value of P. olivaceus as well as to provide a reference for muscle quality appraisal of P. olivaceus. In addition, to provide theoretical basis for further investigation of culture technology and artificial diet develop of P. olivaceus. The results illustrated as follows:The morphology analysis of three kinds of growth models of P. olivaceus showed that the hepatosomatic index(HSI) of W group was lower than P and F groups(P< 0.05), but there was no significant difference between P and F groups(P> 0.05). No significant difference was shown in condition factor(CF) and flesh content of P. olivaceus in the three growth models(P> 0.05).The proximate compositions of P. olivaceus’ s whole fish, muscle, liver and skin in the three growth patterns were analyzed respectively, showed that the crude protein and ash of the pond cultured P. olivaceus whole fish remained similar to that of the wild ones, while moisture of the factory cultured P. olivaceus whole fish remained similar to that of the wild ones. Crude lipid of the P. olivaceus whole fish in the three growth models showed that P > F >W(P< 0.05). The moisture, crude protein and ash content of liver in wild P. olivaceus were higher than P and F groups, while crude lipid of the P. olivaceus’ s liver in the three growth models showed that F > P >W(P< 0.05). The factory group respectively exceeded P and W groups with 82.31%, 150.03%. High level of crude lipid in liver might induce hepatic steatosis for factory cultured P. olivaceus. Crude lipid of the wild P. olivaceus skin on either eye-side or blind-side was higher than pond and factory cultured ones(P< 0.05). Wild P. olivaceus’ s muscle with high protein and low lipid characteristic, pond cultured was similar to the wild.For flesh quality evalution, the muscle water holding capacity, collagen content, muscle fiber diameter and textural characteristics analysis of these three growth pattern were analyzed, results illustrated as follows, drip loss rate of the P. olivaceus muscle on either eye-side or blind-side in the three growth models showed that W > P > F(P< 0.01). The water losses of factory group were higher than that of the wild and pond groups(P< 0.01), while the W and P groups showed no significant difference(P> 0.05). No significant difference was shown in collagen content and muscle fiber diameter of the P. olivaceus muscle on either eye-side or blind-side in the three growth models(P> 0.05). Through principal component analysis, it can be found that the adhesiveness and gumminess were the main factors that reflected the textural characteristics of the P. olivaceus muscle. The factory cultured P. olivaceus showed better water holding capacity, while the physicochemical quality and textural characteristics of the pond cultured P. olivaceus muscle remained similar to that of the wild P. olivaceus. The results indicated that there was no remarkable advantage in physicochemical quality of the wild P. olivaceus.All 17 kinds of amino acids were dectected in three growth models of P. olivaceus, glutamic acid(GLU) content was the highest. The results showed that the content of ∑AA, ∑EAA ∑NEAA and ∑HEAA in wild P. olivaceus were higher than factory cultured P. olivaceus(P<0.05), but there was no significant difference between wild and pond cultured P. olivaceus(P>0.05). No significant difference in ∑DAA of three growth models of P. olivaceus(P>0.05). According to the criteria of amino acid score(AAS) and chemical score(CS), the first limiting amino acid in muscle was valine(VAL). VAL had the highest score of AAS and CS. The score of AAS and CS, essential amino acid index(EAAI) of P. olivaceus were W > P > F. It was illustrated that the wild P. olivaceus had a relatively reasonable amino acid profile. From the amino acids nutritiontal value, the pond cultured P. olivaceus was similar to the wild ones.The muscle fatty acid profiles of P. olivaceus in these three growth models were analyzed, 17 kinds of fatty acid(with the content of over 0.5%) were detected in P. olivaceus. In all three kinds of P. olivaceus, similar trend of PUFA>SFA>MUFA was found. PUFA was the most abundant kind of fatty acid in these P. olivaceus, which between 40.88%-45.91% while n-3 PUFA was the major species in them. However, differences of fatty acid profiles were found in the three kinds of P. olivaceus. PUFA, DHA+EPA and n-3 PUFA in wild P. olivaceus were significantly higher than those in pond or factory cultured P. olivaceus(P < 0.05). n-6 PUFA content of factory cultured P. olivaceus was found to be higher than the other two groups. Consider about the fatty acid nutrition, the flesh quality of factory cultured P. olivaceus is better than the others, and followed by pond cultured P. olivaceus.No significant difference was showed in muscle Fe, Cu, Cr and Ni content of among three kinds of P. olivaceus(P> 0.05). The content of Zn in the muscle of pond cultured P. olivaceus was higher than that of the wild ones(P< 0.05), while no significant difference was observed between pond and factory ones(P> 0.05). The content of Se in the muscle of pond cultured P. olivaceus was higher than the factory cultured ones(P< 0.05), while no significant difference was found between pond and wild ones(P> 0.05). The content of Mn in the muscle of pond cultured P. olivaceus was the highest, no significant difference was observed between factory cultured and wild ones(P> 0.05).