Research On The Migration Of Eugenol In Curdlan Film And Its Odor Detection Technology

With the increasing concerns about food safety and the environment,bio-based packaging materials have become eco-friendly alternative to conventional plastics due to their biodegradability and sustainability.Curdlan are gradually gaining attention due to their excellent film-forming properties.Active substances such as eugenol are widely used in food packaging to improve the quality of packaging or food products due to their excellent antioxidant and antibacterial abilities.However,the migration of active substances may occur during the contact between packaging and food,which may threaten human health.Therefore,the research on the migration of active substances in packaging materials and the development of relevant detection technologies are of great significance and application value.In this paper,the biodegradable packaging film was prepared by using curdlan as the substrate and eugenol as the active substance,and explored the physical properties and active functions of the film.The safety of the eugenol-curdlan film was evaluated by the migration test of packaged jam.Then,we studied the migration pattern of eugenol in the film to 4%acetic acid food simulant,and established the migration model of eugenol in the food simulant based on the migration data.Finally,based on the odor characteristics of eugenol,the method for the determination of eugenol content in curdlan films/jams was developed based on Electronic nose(E-nose)/Gas chromatography-ion mobility spectrometry(GC-IMS),respectively.The details of the study and the results are as follows:1.Determination of the performance of eugenol-curdlan active filmA series of curdlan active films with different concentrations of eugenol were prepared by a casting method and the effect of eugenol on the performance of curdlan film was studied.The results showed that the addition of eugenol has no significant effect on the thickness,water vapor permeability and mechanical properties of the curdlan film.The film thickness was thin and the water vapor barrier performance was not well;the tensile strength and elongation at break could meet the basic requirements of packaging.In addition,the addition of eugenol caused a decrease in light transmission rate and a significant increase in opacity of the film while adding color to the film.With the increase of eugenol concentration,the DPPH radical scavenging activity of biofilm increased significantly until it was stable.The bacteriostatic experiment showed that the addition of eugenol improved the bacteriostatic rate of eugenol-curdlan film,but the overall inhibition effect of eugenol-curdlan film on E.coli was not observed.The overall results showed that the best performance of curdlan film could be obtained when the addition of eugenol was greater than 40 mg/g.2.Migration study of eugenol of curdlan films in food simulantsThe migration of eugenol in jam after contact with E-60 film was measured using eugenol,the active additive in curdlan film,as the target material of the study.The results showed that the residual amount of eugenol in all jam samples was higher than the minimum standard limit of 9.6 mg/kg,suggesting that eugenol-curdlan active films packaging jam had certain safety risks.The migration of eugenol from the curdlan film to the 4%acetic acid food simulation solution was studied.It was found that the migration amount increased rapidly at first and then gradually stabilized with the increasing of time,and increased significantly with the increase of eugenol concentration and temperature.Based on the migration data,a Weibull model of eugenol migration in 4%acid was established,and the relationship between the model parameters and the amount of eugenol,temperature and time was obtained.It was proved that the predicted value of this model was in good agreement with the measured value,and it could be used to predict the migration of eugenol from curdlan in jam food.3.Study on the method of detecting eugenol content in curdlan films based on electronic nose systemThe actual concentration of eugenol in curdlan active biofilms with different eugenol concentrations was measured firstly.Gas chromatography-mass spectrometry(GC-MS)and E-nose were used to analyze the volatile components in different film samples.The differentiation of curdlan films with different eugenol additions was achieved by principal component analysis(PCA)and linear discriminant analysis(LDA).Based on the sensors,the model for the determination of the eugenol in curdlan film was established by partial least squares(PLS)and support vector machine method(SVM).The results showed that the best prediction model for eugenol concentration was the PLS prediction model based on all sensors with R_P~2of 0.952.This study described a rapid,nondestructive detection and quantification method for determining the concentration of eugenol in bio-based packaging materials.4.Establishment of a method for detecting eugenol content in jam based on GC-IMSA new method based on GC-IMS was developed for the determination of eugenol in jams with different concentrations of eugenol.According to the standard curve of calibration solution,eugenol was characterized and the concentration information was extracted.The standard working curve of eugenol in jam was determined by optimizing the injection volume,injection speed,incubation time and temperature.The results showed that the Boltzman distribution(R~2>0.987)was observed;among them,the curve fitting with the peak height as the signal intensity value was optimal.The limit of quantification and the limit of quantification of this method were 0.1 mg/kg and 0.05 mg/kg respectively by selecting the appropriate Signal-noise ratio(SNR).The average recoveries of eugenol were77.6%-125.6%and the relative standard deviations were less than 20%,which indicated that the method had good stability and could be used for the determination of eugenol content in jam food.