Comparison and evaluation of nutrient composition of two ecological groups of Japanese grenadier anchovy-river-anchovy and sea-anchovy

In this study,to evaluate the fish quality,the nutritional composition of two ecological groups of Japanese grenadier anchovy(river-anchovy and sea anchovy) were analyzed.The results showed that the crude lipid content of the whole fish in river-anchovy was significantly higher than that of sea anchovy(P 0.01) and was 2.03 times higher.However,the crude protein,moisture and ash content were less than that of sea anchovy;two ecological groups of Japanese grenadier anchovy have almost the same amino acid composition,and both contain 18 amino acids,accounting for 11.55% and 15.37 % in wet weight respectively.We also found that the content seven kinds of EAA(Leu,Ile,Phe,Try,Thr,Val,Lys),the HEAA(Arg) and four kinds of NEAA(Glu,Ser,Tyr,Pro) in the two species have a significant difference(P0.05),8 essential amino acid content in the fresh fish is 4.87% and 6.4%,while the ratio of non-essential amino acids were 85.59% and 83.44%.It is basically in agreement with the standard value issued by FAO(Food and Agriculture Organization) in the United Nations and WHO(World Health Organization).Moreover,the essential amino acid index(EAAI) was calculated and were 22.32 and 41.82;branched-chain amino acids and aromatic amino acid ratio(F value) were 2.43 and 2.49.Four kinds of amino acid content in river-anchovy(4.59 %) was significantly lower than that of sea anchovy(6.12%);The taurine content of river-anchovy was as high as 265.43 mg/100 g,which was significantly higher than that of sea anchovy.20 kinds of fatty acids in river-anchovy were identified by using methyl esterization,which included 9 saturated fatty acids(SFA),5 single-unsaturated fatty acids(MUFA) and 6 polyunsaturated fatty acids(PUFA).The polyunsaturated fatty acids(9.05 %) in Coilia nasus was significantly lower than that of sea anchovy(13.20%).Similarly,this tendency toward decreased EPA and DHA was also observed in river-anchovy(4.21%,2.26%) as compared to sea anchovy(6.71%,2.92%).However,river-anchovy have a pronounced higher level of absolute content than that of sea anchovy(P0.05);ω3 PUFA/ω6 PUFA values were 2.67 and 2.87.All the fish are rich in mineral content,especially selenium.The content of Na,Mg,Se in river-anchovy and sea anchovy are significantly different.Overall,the present study will necessitate further research efforts to the establishment of standards and provide identification information for the two kinds of Coilia nasus ecological groups.