| Soy sauce is one of the most important condiments in Chinese daily life,therefore,the detection and inhibition of the hazards in soy sauce is necessary to ensure the quality and safety.N?-(carboxymethyl)lysine(CML)and 5-hydroxymethylfurfural(5-HMF)are harmful components in soy sauce,which can induce various chronic diseases and even cancer in human body.Thus,it is important to detect and control the CML and 5-HMF for the products safety.However,the high-efficiency detection methods and valid inhibitors to CML and 5-HMF for soy sauce are still inadequate.At present,many of the detection methods for harzards in soy sauce have a low accuracy,and the detection objects are limited to the soy sauce in store,lacking of the samples in the production process of soy sauce.Based on this,a simultaneous detection method was established to analysis CML and 5-HMF in soy sauce in this paper.The effect of three kinds of natural antioxidants(epicatechin,EC;epicatechin gallate,EGCG;ascorbic acid,VC)to the CML and 5-HMF were explored in model system and soy sauce.The main results are showen as follows:(1)Establish a simultaneous detection method for free CML and 5-HMF in soy sauceOptimizing the pretreatment methods,chromatographic conditions and mass spectrometry parameters,a method for simultaneous detection of free CML and 5-HMF in soy sauce was established by high performance liquid chromatography-mass spectrometry system(HPLCMS/MS).The detection only took 5 min for per sample.The LOD of CML and 5-HMF is 0.3 ng/mL and 6.0 ng/mL.The recovery and RSD are 98~102% and 4~12% respectively.These results suggested that the method had many advantages,including high detecting efficiency,high sensitivity and high accuracy.(2)Detection CML and 5-HMF content in soy sauce production processThe CML and 5-HMF contents were detected using the established method.And the physicochemical indexes and the levels of two hazards were analysis during the soy sauce production process and different market soy sauces.The results showed that the soy sauce raw materials,soy sauce production and soy sauce types were the key factors affecting the content of CML and 5-HMF in soy sauce.In addition,the results of Spearman's correlation analysis suggested that the content of CML in raw materials was the main factor affecting the level of CML in soy sauce production and the blending link would lead to the increase of 5-HMF level in soy sauce samples.The levels of CML and 5-HMF in the different market soy sauces were synergistic.(3)Influence of nature antioxidants on CML and 5-HMF in model systemThe effects of heating time,three different natural antioxidants with different dosages on the formation of CML and 5-HMF were investigated in two model systems.The substrates of model system,the kind of nature antioxidants and their dosages are all the factors to affect the content of CML and 5-HMF.Specific concentration of EC and VC could inhibit the formation of 5-HMF.Specific concentrations EGCG could inhibit the formation of CML.Especially,VC had a good ability to clear both existed CML and 5-HMF in the model system.(4)Influence of thermal treatmenton and antioxidants on CML and 5-HMF in soy sauceTaking the real soy sauce system as the research object,the comprehensive effects of heat treatment and nature antioxidants on CML and 5-HMF in the soy sauce system were investigated.EC,EGCG and VC could reduce the content of CML and/or 5-HMF in the real soy sauce system under certain conditions.And the effect was decided by both heat treatment process and nature antioxidants concentration.The method for simultaneous detecting free CML and 5-HMF in soy sauce by HPLCMS/MS was established in this study,which could be provided as a technical reference for the detection of hazardous substances in various liquid seasonings and beverages.The regulation of natural antioxidants as inhibitors to control the CML and 5-HMF in soy sauce provides a theoretical basis for reducing the levels of hazards in real food systems. |
PDF Full Text Request