Inhibition And Mechanism Of Tea On The Formation Of Heterocyclic Aromatic Amines In Roasted Fish

Heterocyclic aromatic amines(HAAs)are a kind of carcinogen that are easy to be generated when meat is cooked at high temperature.Their formation is affected by such factors as cooking time,temperature,type of animal meat used,cooking method,concentration of precursors and addition of antioxidants.Adding antioxidants during the cooking process can to some extent inhibit the generation of HAAs.Tea can be used for deodorization during fish processing,and its main active ingredient,tea polyphenols,has antioxidant properties.This article selects grass carp meat pretreated with tea as the research object to explore its effects on 2-amino-1-methyl-6-phenylimidazolo [4,5-b]pyridine(Ph IP),2-amino-3,8-dimethylimidazolo [4,5-f] quinoxaline(Me IQx),2-amino-9H-pyridino [2,3-b] indole(AαC),2-amino-3,4-dimethylimidazolo [4,5-f] quinoline(Me IQ)The inhibitory effect of 2-amino-3-methyl-3H-imidazoloquinoline(IQ)generation.And by studying the effect of heating treatment on the various antioxidant abilities of tea polyphenols,the inhibitory mechanism of tea on heterocyclic amines in roasted fish meat was studied.The main research content and experimental results are as follows:1.A HAAs detection method based on solid phase extraction(SPE)and liquid chromatography mass spectrometry(HPLC-MS)technology has been developed.Extract HAAs from the fish flesh with 1 M Na OH and then add acetonitrile acetic acid as a liquid to liquid extraction solution.Then enriching HAAs using small columns of HRP SPE,and finally detecting HAAs production using HPLC-MS.As can be seen,the recovery rate of the internal standard was 73.9%,and the linear correlation coefficients of the HAAs standard curve were all greater than 0.99,indicating a good linearity.The limits of detection for several HAAs tested are all within 0.02～0.06 ng/g,and the limits of quantitation are all within 0.06～0.13 ng/g.2.In order to determine the effect of heating treatment on the oxidation performance of tea polyphenols.By altering the soaking time and heating temperature of the tea leaves,the changes in tea polyphenol content in the tea water were compared in order to determine the conditions for tea water preparation.Tea polyphenols are heat treated to study the trend in their antioxidant properties.It was found that at 100 °C soaking for 30 minutes resulted in the highest dissolution rate of the tea polyphenols,which was as high as 86.5%.Therefore,in the present experiment,this temperature and time were used to prepare the tea.As the heating temperature increases,the relative capacity of tea polyphenols to scavenge free radicals decreases;The longer the heating time at the same temperature,the poorer the relative capacity of the tea polyphenols to scavenge free radicals.The relative radical scavenging capacity of the DPPH free radicals of tea polyphenols decreased the least under the 150 °C heating condition for 10 minutes to 81.9%;The total relative antioxidant capacity,hydroxyl scavenging capacity,and superoxide anion scavenging capacity all decreased to approximately half of the original value,while the relative reducing capacity decreased the most to 17.9%.3.In order to determine the effect of tea on HAAs formation in roasted fish meat and to analyze its quality.To detect physicochemical properties of fish meat,to analyze changes in quality and HAAs generation of roasted fish meat following the addition of tea.For the detection of HAAs in broiled fish,the extraction and detection methods of Chapter2 were used.It was found that the HAAs generation in the roasted fish meat was relatively poor at 180 °C,with no signal detected in Aa C,IQ and Ph IP;Me IQ actually increases with increasing tea content in the tea,whereas Me IQx does not have a significant change.One possible explanation for this is that the amount of HAAs generated is too small to generate a dose-effect relationship.Aa C,IQ and Ph IP are detected when the transformation temperature is increased to 230 °C;At 270 °C,there is a significant increase in IQ and Ph IP in grilled fish meat.At processing temperatures of 230 °C and 270 °C,the content of HAAs in roasted fish meat decreased with the increase of the amount of tea used for tea preparation.This increase in temperature will reduce the antioxidant activity of the tea polyphenols in the tea,resulting in an increase in the HAAs content.On the other hand,as the amount of tea added in the tea increases,it has some inhibitory effect on HAAs generation.One possible mechanism is that tea contains polyphenols from the tea,which inhibit the production of free radicals in HAAs intermediate products such as phenylacetaldehyde and pyrazine cation,leading to a decrease in HAAs production.1,2,3,4 However,this mechanism may not be fully understood.