Aflatoxin B₁ On-line Testing Technology In The Stages Of Pixian Bean Paste Producing

Pixian bean paste is one of important condiments in Sichuan dishes,and is an integrant seasoning matter for people's every meal,and is also the cornerstone industry of traditional agricultural product processing in our city. Existing national standards have provided aflatoxin testing methods for some product,at the same time, sample pretreatment is very important in the process of aflatoxin testing,so that testing methods for finished product can't be directly used in raw material and Semi-manufactured bean paste.Firstly,we analysed and compared the operational safety,testing time and cost etc for aflatoxin B₁ testing by Thin Layer Chromatography (TLC),Enzyme Linked Immunosorbent Assay(ELISA) and High Performance Liquid Chromatography(HPLC),ELISA is superior to TLC and HPLC in operational safety,economic cost and applicability for enterprise. In the end,we use ELISA to research the aflatoxin B₁ on-line testing technology in the stages of Pixian bean paste producing.We use the ELISA to research the best testing conditions of aflatoxin B₁ on-line testing technology in the stages of Pixian bean paste producing.First,we have to define the reliability of the detection of ELISA kit, The result showed that the linear range of analytical method of this ELISA kit is 0.1～8.0ng/ml,and the detection sensityvity is 0.1ng/ml, Intra-assay and inter-assay coefficient of variability (CV) are all less than 5%, the average recovery rate is 97.88% in linear range. According to the results,this ELISA kit is really featured by reliable, high sensibility for aflatoxin B₁ detection.And then,we Instituted pre-treatment methods of different samples,and analysed the conditions for aflatoxin B₁ detection by ELISA . In this paper,we mainly made an on-the-spot investigation from kind and dosage of extract,extracting time and method, finally we got the best extracting condition for aflatoxin B₁ by response surface design (Box-Behnken design).Experiment results show that the best experiment conditions of aflatoxin B₁ extracting from raw material broad beans were as follows: methanol concentration is 43.41%, ratio of sample to solution is 1:5.35, ultrasonic extraction time is 39.89min, detecting of raw material broad beans can achieve its maximum value for 1.50μg/kg by this optimized condition; the best experiment conditions of aflatoxin B₁ extracting from koji bean were as follows: methanol concentration is 39.66%, ultrasonic extraction time is 27.70min, ultrasonic extraction power is 88.97%,detecting of koji bean can achieve its maximum value for 1.47μg/kg by this optimized condition. The best experiment conditions of aflatoxin B₁ extracting from chilli soy sauce mash were as follows: methanol concentration is 43.01%, ratio of sample to solution is 1:6.34 ,ultrasonic extraction time is 40.99min , detecting of chilli soy sauce can achieve its maximum value for 1.32μg/kg by this optimized condition; the best experiment conditions of aflatoxin B₁ extracting from Pixian soybean paste were as follows: methanol concentration is 60.80%, ratio of sample to solution is 1:6.24,ultrasonic extraction time is 20.70min ,detecting of Pixian soybean paste can achieve its maximum value for 3.22μg/kg by this optimized condition.Content of aflatoxin B₁ in samples for all research in range of 1～3.5μg/kg,and achieved the best efficiency of extraction; experimental models are all notable, The coefficient of determination and the RSD is 0.94 and 5%, respectively, it is found that the experimental data agree well with the response value, this method is really featured by reliable, high sensibility and efficiency for aflatoxin B₁ detection.