Gel Properties And Volatile Components Of Pagrosomus Major Surimi Gels With Adding Chenopodium Quinoa

Chenopodium quinoa Willd is a dicotyledon pseudo-cereal that original been cultivated in the South America with great adaptability to different growing conditions.Chenopodium quinoa Willd is rich in protein,starch,minerals,vitamins and bioactive compounds that been called of "all-round grain",can also play an important role in the prevention and treatment of diseases,maintenance health and improve the body metabolism of human.Pagrosomus major is one of the most important cultured marine fish in China,which with tender meat,delicious taste,nutritious and rich in protein.The surimi industry has changed dramatically over the past decades,the development of processing technology has opened a door for the utilization of new fish species in surimi industry.Recent years,pagrosomus major surimi has became one of the most commonly used materials in China's ready-to-eat surimi products.Exogenous additives' effect on the gel properties and flavor of surimi products has been reported in many researches,and also quinoa has been used in many foods because of its nutritional value and efficacy as food.Gel properties and flavor are the most intuitive criteria for the quality assessing of surimi products.Gel properties and volatile components of pagrosomus major surimi gels with adding Chenopodium quinoa Willd were studied,aimed to fully find out the nutritional properties of pagrosomus major surimi,provide data references for pagrosomus major surimi's processing and research&development,also open up a new way to improve the quality of surimi products and utilization of quinoa resources.Pagrosomus major surimi was choosed as research object in this study.Firstly,the nutrient composition was analyzed and evaluated.Then,gel strength,water holding capacity,whiteness,chemical bonds,TCA-soluble peptide and SDS-PAGE were determined to assessed the effects of adding quinoa on the gelation performance and protein structure of pagrosomus major surimi.Finally,HS-SPEM-GC-MS was used to analyze the volatiles compounds of pagrosomus major surimi and pagrosomus major surimi with chenopodium quinoa.Combined with the results of mass spectrometry and retention index,used relative odor activity value to determine the characteristic flavor compounds of two kinds of surimi products.The research results are as follows:The moisture content of pagrosomus major surimi was the highest,reached 79.35%,followed by crude protein(12.72%),crude fat(3.71%)and ash(2.42%).Glu,Lys,Asp and Leu are the four amino acids with the highest contents in pagrosomus major surimi.The essential amino acids accounted 44%of the total amino acids,and the ratio of essential amino acids to nonessential amino acids was 88%,all bigger than the ideal model of the FAO/WHO standard.And the Essential Amino Acid Index was 99.69.The content of unsaturated fatty acids was higher than saturated fatty acids,palmitic acid(29.86%)was the highest in monounsaturated fatty acids and the content of polyunsaturated fatty acids was 36.70%,DHA(20.38%)and EPA(7.49%)were the richest two parts.Pagrosomus major surimi was rich in sodium,magnesium,potassium,phosphorus,and contained iron,selenium,zinc and manganese.The addition of quinoa had some effect on the gel properties and protein structure of pagrosomus major surimi.When the contents of quinoa in the range of Og/100g-3g/100g,gel strength of surimi increased with the contents increase,when the amount reached to 3g/100g,gel strength of surimi showed a decreasing trend,but compared with the control group,there was still a significant increase(P<0.05).Whiteness decreased with the increase of quinoa,while water holding capacity increased with the increase of quinoa.With the increase amount of quinoa,the change of ionic bond was not significant,the hydrogen bond tended to decrease,and the hydrophobic interaction and disulfide bond showed a rising trend.TCA-soluble peptides showed a decreasing trend with the increase of quinoa.The results of SDS-PAGE showed that the addition of quinoa had a positive effect on the covalent cross-linking of myosin heavy chain.An appropriate addition of quino in pagrosomus major surimi could enhance its gel strength and water holding capacity inside the gel network structure,provide force for the folding of proteins,increase the covalently crosslink,enhance gel elasticity,protein degradation can also be inhibited by adding quinoa.Based on the analyzed of pagrosomus major surimi and pagrosomus major surimi with chenopodium quinoa by HS-SPME-GC-MS,35 and 32 kinds of volatile compounds were detected respectively.Those compounds are mainly aldehydes,hydrocarbons and aromatic compounds.The relative odour activity values(ROAV)were used to indicate the effects of different volatile components on the overall flavor of two kinds surimi products,6 and 7 key flavor compounds were identified respectively.The composition and relative content of volatile compounds in two kinds of surimi were not too different from eachother.For the two kinds of pagrosomus major surimi,nonanal was the compound with the highest relative content and with a very low sensory threshold,which was considered to be the most prominent flavor compound.Besides,aldehydes including hexanal,dodecanal,undecanal and benzaldehyde,have a significant contribution to the flavor of two kinds of pagrosomus major surimi.Ketone including 2-Undecanone,2-Nonanone,aromatic compounds including ethylbenzene,o-xylene,naphthalene,and 1-methy1-naphthalene also have some contribution to the flavor of two kinds of pagrosomus major surimi.In general,the addition of quinoa has little influence on the overall flavor of pagrosomus major surimi.The results also showd that the composition of the main flavor is not complicated among the two kinds of pagrosomus major surimi,their flavor were pleasant,which is in line with the requirements of the surimi products as represents a system that is primarily developed to have little or no flavor at all.The addition of quinoa has some but not significant effect on key flavor compounds,relative content.Indicating that the effects of adding quinoa on the volatile flavor of pagrosomus major surimi are acceptable.