Evaluation And Reduction The Contamination Of Antibiotic In Auricularia Auricula And Its Products

Auricularia auricula has rich nutritional value and high economic benefits.In recent years,its planting scale and yield have been expanding.However,pesticide residues,heavy metals,antibiotics,molds,and mycotoxins pose a great threat to the quality and safety of Auricularia auricula and its products.It is of great significance to study a method system for controlling these pollutants to ensure the quality of Auricularia auricula.Therefore,this study focused on the pollution and residue antibiotics in the cultivation of Zhashui Auricularia auricula.Systematically analyzed the background pollution value,source and migration rule of antibiotics and established the HACCP system in the cultivation process of Auricularia auricula.Then we constructed the antibiotic control technology with non-thermal treatment,in order to provide data and technical support for antibiotic control in the cultivation and processing of Auricularia auricula.The main research contents and results are as follows :(1)Systematically analyzed the rules of antibiotic residues and migration during the cultivation of Auricularia auricula,and established the HACCP control system.Based on Qu ECh ERS pretreatment and HPLC-MS/MS detection method,realized the rapid detection of antibiotics in Auricularia auricula.For 8 antibiotics in 3 categories,the minimum detection limit was 2-15 μg/kg,the limit of quantitation was 5-49 μg/kg,and the recovery rate was 80.61-116.22%.On this basis,we determined the change trend of the content of antibiotics at the key limit points during the processing of Auricularia auricula.The residual antibiotics were degraded to varying degrees in each stage and the degradation rate of antibiotics during sterilization,mycelium culture and harvesting was higher,in which ciprofloxacin and enrofloxacin decreased by 8.11% and 8.49%,12.41% and 16.19%,7.93%and 10.27%,respectively.The degradation rate of antibiotics during the growth of Auricularia auricula was 44-53%.Based on the above data,the HACCP system of the cultivation process of Auricularia auricula was constructed,the key limits of environmental conditions and antibiotic limits,the monitoring procedures of methods,personnel and frequency were determined,and established the corrective measures,verification steps and the plan table of recording methods.So as to effectively supervise and make preventive measures,ensure the quality and safety of Auricularia auricula and its products.(2)Systematically analyzed the drying efficiency of natural drying,hot air drying and vacuum microwave drying on Auricularia auricula,and evaluated the effects of different treatments on the physicochemical properties of Auricularia auricula and the degradation effect of quinolones(enrofloxacin,ciprofloxacin).The results showed that the drying time of Auricularia auricula was greatly shortened to 150 min under the condition of hot air drying at 80°C,and further shortened to 15 min under the condition of 2.4 k W vacuum microwave drying.The contents of crude protein,crude fat,crude fiber and ash in Auricularia auricula were not significantly affected by hot air drying and vacuum microwave drying(P>0.05).After treatment,the total sugar content decreased by 1.34% and 2.28%,respectively,and the physicochemical indexes still met the national standard requirements.In addition,the degradation rates of enrofloxacin and ciprofloxacin during natural drying were 16.32% and14.22%,respectively.The degradation rates of the two antibiotics were 35.37% and 32.39%,respectively,under the condition of 80°C hot air drying,and 36.11% and 33.19%,respectively,under the condition of 2.4 k W vacuum microwave drying,indicating that there was no significant difference in the degradation of antibiotics between the two treatment methods(P>0.05).Therefore,vacuum microwave drying has short processing time and high efficiency,has little effect on the physical and chemical indexes of Auricularia auricula and has good degradation effect of antibiotic residues,which provides a new idea for drying and quality safety control of edible fungi.(3)The antibiotics in Auricularia auricula were treated by ultrasonic assisted low temperature plasma activated water,and the optimum process was obtained by response surface design optimization.The results showed that the degradation rates of ciprofloxacin and enrofloxacin(initial concentration of 0.5 mg/kg)were 51.92% and 55.47%,respectively,based on the low-temperature plasma activated water with the dielectric barrier discharge device with an output voltage of 4 k V and a frequency of 10 k Hz,combined with ultrasonic treatment(power 500 W,time 45 min,temperature 30°C,frequency 25 k Hz).After treatment,the contents of total sugar,crude protein and crude fat in Auricularia auricula decreased by5.24%,1.24% and 0.12%,respectively,which all met the requirements of physicochemical indexes of Auricularia auricula in GB/T 6192-2019,which provides a new idea for antibiotic control of Auricularia auricula.(4)Based on pulsed light treatment,an efficient control technology for antibiotic residues in Auricularia auricula and its extracts was established.The results showed that when the light distance was 5 cm and the number of flashes was 30 times,the degradation rates of enrofloxacin and ciprofloxacin(concentration 0.5 mg/kg)in Auricularia auricula were 82.84% and 81.10%,respectively.The degradation rates of the two antibiotics in the extract of Auricularia auricula could reach 99.17% and 98.61%.After pulsed light treatment,the total sugar content of Auricularia auricula was reduced by 12.25%,and the physical and chemical indexes such as crude protein,crude fiber,ash and crude fat content did not change significantly(P>0.05),and its nutritional components still met the national standard requirements.The ΔE of the chroma of the extract was 1.51,and the color of the extract was relatively dark.There was no significant change in p H value and transmittance(P>0.05).The above studies showed that pulsed light treatment had better antibiotic treatment effect and had no significant effect on the quality of Auricularia auricula and its extract.This study provided a new method for the control of antibiotics in the processing of edible fungi.