Development Of Capillary Electrophoresis Indirect Ultraviolet Method For Detection Of Biogenic Amines And Its Application In Food

Common biogenic amines（BAs）in food mainly include putrescine（Put）,histamine（HA）,cadaverine（Cad）,spermidine（Spd）,spermine（Spm）,ethanolamine,phenethylamine,Tryptamine,Tyramine（TA）,Agmatine etc.Excessive intake of BAs from food may cause some serious symptoms of poisoning,such as dizziness,nausea,neurotoxicity,and renal insufficiency.Therefore,it is very important to develop an analytical method that can quickly and sensitively detect the content of BAs in food.In this paper,capillary electrophoresis（CE）indirect-ultraviolet method was developed to detect 10 common BAs in food.This method was used to analyze the changes in the concentration of BAs in raw and cooked chicken,beef,and pork samples under different storage conditions.At the same time,a simple sample preparation method was developed and used for luncheon meat samples with different protein content.And the changes of BAs concentration in the pre-treated luncheon meat samples were analyzed during the storage period.Firstly,an accurate and fast CE with indirect-UV detection method was developed to study 10 BAs.It was found that β-cyclodextrin（β-CD）was beneficial to the separation of Try and TA,EDTA achieved baseline separation of Spd and Spm,and methanol reduced EOF.The optimized BGE was composed of 20.0 mmol/L Im,8.0 mmol/L β-CD,0.5 mmol/L EDTA,and6.0% methanol（p H 4.50 adjusted with acetic acid）.Under these conditions,the obtained limits of detection（LODs）（S/N = 3）ranged from 0.14-1.98 mg/L.The relative standard deviation（RSD）of the migration time and peak area during the day were less than 1.15% and 4.66%（n= 6）,respectively.Based on the developed CE indirect-UV detection method,the content of BAs in raw and cooked chicken,beef,and pork samples was detected.It was found that the BAs content in chicken had the most obvious change.Whether it was raw or cooked meat samples,the storage temperature had a decisive influence on the content of BAs.Through comparison between raw and cooked meat samples,the characteristics of the changes in the content of BAs found that heating the raw meat samples could kill the microorganisms in the raw meat,thereby reducing the concentration of BAs during storage.Due to the thermal stability of BAs,the heating procedure would not affect the natural BAs in meat and meat products.In addition,it was found that the type of meat affects the concentration of BAs.By analyzing the BAI in samples,the quality of the sample was evaluated,and consumers were guided to store meat and meat products at low temperatures.In particular,raw meat was not recommended to be stored for more than 2 days at low temperature.This method was further used to determine the content of BAs in canned luncheon meat with complex composition.The matrix interference was weakened or eliminated by the deionized water washing.This pre-treatment method will not reduce the concentration of Spd and Spm in the sample,nor will it affect the accumulation of other BAs concentrations.During the storage process,Put and Cad were the main BAs of luncheon meat,and the content of TA was affected by factors such as sample raw materials and processing methods.The protein content of luncheon meat（pork content）also had an influence on the concentration of BAs.On the 7th day of storage at 25℃,the Put and Cad content in the high-protein luncheon meat sample was 10 times and 2 times that of the low-protein luncheon meat samples,respectively.Similarly,storage temperature also played a decisive role in the concentration of BAs.