阅读说明：本技术 一种食品防腐剂含量安全检测方法 (Food preservative content safety detection method ) 是由 唐菲 石平 宋晓婉 茌梦雨 陈文新 雷蕾 于 2020-12-14 设计创作，主要内容包括：本发明公开了一种食品防腐剂含量安全检测方法,涉及防腐剂检测技术领域。本发明包括从待检测食品的多个不同部位随机取样,注入盐酸溶液,震荡,离心,过滤操作,得到过滤液；向获取的过滤液中加入吸附剂,震荡,用乙醇涡旋解析获得解析液,用氮气吹干后,再用乙醇溶解得到样品溶液；将得到的样品溶液与净化剂混合固液分离,收集上层清液；进行液相色谱—质谱仪分析,检测出防腐剂种类和含量。本发明通过向过滤液中加入吸附剂,向样品溶液中加入净化剂进行混合,去除了影响检测结果的杂质,保证了检测结果的准确性,采用液相色谱—质谱仪分析,具有检测范围广,操作简便,检测效率高的优点。(The invention discloses a food preservative content safety detection method, and relates to the technical field of preservative detection. Randomly sampling different parts of a food to be detected, injecting a hydrochloric acid solution, oscillating, centrifuging and filtering to obtain a filtrate; adding an adsorbent into the obtained filtrate, oscillating, performing vortex analysis by using ethanol to obtain an analysis solution, drying by using nitrogen, and dissolving by using ethanol to obtain a sample solution; mixing the obtained sample solution with a purifying agent for solid-liquid separation, and collecting supernatant; and (5) performing liquid chromatography-mass spectrometer analysis to detect the type and content of the preservative. The invention removes the impurities influencing the detection result and ensures the accuracy of the detection result by adding the adsorbent into the filtrate and adding the purifying agent into the sample solution for mixing, and the invention adopts the liquid chromatogram-mass spectrometer for analysis and has the advantages of wide detection range, simple and convenient operation and high detection efficiency.)

1. A method for safely detecting the content of food preservatives, wherein the preservatives comprise dimethyl fumarate, dehydroacetic acid, benzoic acid, dimethyl p-hydroxybenzoate, diethyl p-hydroxybenzoate and diisopropyl p-hydroxybenzoate; the method is characterized in that: the detection method comprises the following steps:

step1, randomly sampling 5 different parts of a food to be detected, putting the parts into a test tube, injecting 10-20mL of hydrochloric acid solution into the test tube, shaking for 1-2min, putting the test tube into a centrifuge, centrifuging for 3-5min, precipitating, and filtering to obtain filtrate;

step2, adding an adsorbent into the filtrate obtained in Step1, shaking for 2-5min, carrying out vortex analysis for 2-3 times by using ethanol, carrying out analysis for 1-2min each time, combining the analysis solutions, drying by using nitrogen, and dissolving by using ethanol to obtain a sample solution;

step 3: mixing the sample solution obtained in Step2 with a purifying agent for solid-liquid separation, and collecting supernatant;

step 4: preparation of a standard mixed solution of preservatives: firstly, mixing preservative standard samples, dissolving the preservative standard samples in methanol to obtain preservative standard sample mixed stock solution, and then gradually diluting the preservative standard sample mixed stock solution by using methanol to obtain preservative standard mixed solution;

step 5: and (3) taking 20 mu L of the supernatant obtained in Step3 by using a pipette, injecting the supernatant into a sample injection valve of a liquid chromatography-mass spectrometer, and carrying out liquid chromatography-mass spectrometer analysis to detect the type and the content of the preservative.

2. The method as claimed in claim 1, wherein the centrifugation speed is 2000-3000 r/min.

3. The method for safely detecting the content of the food preservative according to claim 1 or 2, wherein the adsorbent is carbon nanofibers or graphene oxide.

4. The method for safely detecting the content of the food preservative according to claim 3, wherein the purifying agent is a mixture of graphitized carbon and neutral alumina; the mass ratio of the graphitized carbon to the neutral alumina is 18-23: 25-35.

5. The method for safely detecting the content of food preservatives as claimed in claim 1, 2 or 4, wherein the analysis of the liquid chromatography-mass spectrometer in Step4 includes gas chromatography detection parameters and mass spectrometry detection conditions; the gas chromatography detection parameters comprise that the injection port temperature is 220 ℃, the column temperature is 80 ℃, the initial temperature is kept for 2min, the temperature is increased to 180 ℃ at the speed of 10 ℃/min, the temperature is increased to 240 ℃ at the speed of 15 ℃/min, and the temperature is kept for 14 min; carrier gas: helium with purity not less than 99.999% and flow rate 1.5 mL/min.

Technical Field

The invention belongs to the technical field of preservative detection, and particularly relates to a food preservative content safety detection method.

Background

The food is a basic substance for human life, and the fresh food is a basic condition for guaranteeing human health. In order to ensure the freshness of food, the damage of harmful microorganisms can be prevented by physical methods or chemical methods, and the physical methods usually adopt low-temperature refrigeration, air isolation, drying or high acidity and the like for sterilization; the chemical method is to utilize preservative to kill and inhibit bacteria. Compared with the food fresh-keeping method by a physical method, the preservative is simpler and more convenient to add, and the effect is better.

However, the addition of the preservative in an excessive dosage brings threat to human health, for example, excessive intake of benzoic acid and sodium benzoate will affect the effect of liver enzymes on fatty acid, and then excessive sodium in benzoic acid will also affect the blood pressure, heart and kidney functions of human bodies. Therefore, rational use of preservatives is an important part of food production. The detection of the preservative of the food before leaving the factory is an effective monitoring control method for guaranteeing the health food of human beings. The use of preservatives in food is limited, and excessive preservatives can affect the health of human bodies, so that the detection of the content of the preservatives is important data in the food quality supervision process, and the conventional methods for determining the preservatives mainly comprise a wave layer chromatography, a high performance liquid chromatography, a capillary electrophoresis method, a gas chromatography and the like.

The number of samples is small when the preservative amount of the food is detected at present, and the samples do not cover all positions of the food, so that the detection result can have errors; and with the mixed use of preservatives in the food industry, single detection of a certain preservative has not met the requirements of various industries, so that a method capable of simultaneously detecting multiple preservatives is very important.

Disclosure of Invention

The invention aims to provide a food preservative content safety detection method, which is characterized in that different parts of food to be detected are sampled randomly, and pretreatment of multiple steps is carried out, so that the detection result of the sample is more accurate, and the problem that the existing detection result possibly has errors is solved; the single detection of a certain preservative can not meet the requirements of various industries.

In order to solve the technical problems, the invention is realized by the following technical scheme:

the invention relates to a method for safely detecting the content of food preservative, wherein the preservative comprises dimethyl fumarate, dehydroacetic acid, benzoic acid, dimethyl p-hydroxybenzoate, diethyl p-hydroxybenzoate and diisopropyl p-hydroxybenzoate; the method is characterized in that: the detection method comprises the following steps: step1, randomly sampling 5 different parts of a food to be detected, putting the parts into a test tube, injecting 10-20mL of hydrochloric acid solution into the test tube, shaking for 1-2min, putting the test tube into a centrifuge, centrifuging for 3-5min, precipitating, and filtering to obtain filtrate; step2, adding an adsorbent into the filtrate obtained in Step1, shaking for 2-5min, carrying out vortex analysis for 2-3 times by using ethanol, carrying out analysis for 1-2min each time, combining the analysis solutions, drying by using nitrogen, and dissolving by using ethanol to obtain a sample solution; step 3: mixing the sample solution obtained in Step2 with a purifying agent for solid-liquid separation, and collecting supernatant; step 4: preparation of a standard mixed solution of preservatives: firstly, mixing preservative standard samples, dissolving the preservative standard samples in methanol to obtain preservative standard sample mixed stock solution, and then gradually diluting the preservative standard sample mixed stock solution by using methanol to obtain preservative standard mixed solution; step 5: and (3) taking 20 mu L of the supernatant obtained in Step3 by using a pipette, injecting the supernatant into a sample injection valve of a liquid chromatography-mass spectrometer, and carrying out liquid chromatography-mass spectrometer analysis to detect the type and the content of the preservative.

Further, the speed of the centrifugation is 2000-3000 r/min.

Further, the adsorbent is carbon nanofibers or graphene oxide.

Further, the purifying agent is a mixture of graphitized carbon and neutral alumina; the mass ratio of the graphitized carbon to the neutral alumina is 18-23: 25 to 35.

Further, the liquid chromatography-mass spectrometer analysis in Step4 comprises gas chromatography detection parameters and mass spectrometry detection conditions; the gas chromatography detection parameters comprise that the injection port temperature is 220 ℃, the column temperature is 80 ℃, the initial temperature is kept for 2min, the temperature is increased to 180 ℃ at the speed of 10 ℃/min, the temperature is increased to 240 ℃ at the speed of 15 ℃/min, and the temperature is kept for 14 min; carrier gas: helium with purity not less than 99.999% and flow rate 1.5 mL/min.

The invention has the following beneficial effects:

1. aiming at the problems that the number of samples is small during detection and the detection result is likely to have errors, the invention randomly samples from 5 different positions of the food to be detected in Step1, thereby ensuring the randomness of the detection samples and improving the accuracy of the detection result.

2. The invention sets the vibration and centrifugal operation, adds the adsorbent into the filtrate, adds the purifying agent into the sample solution for mixing, removes the impurities influencing the detection result, ensures the accuracy of the detection result, adopts the liquid chromatogram-mass spectrometer for analysis, can jointly detect various preservatives, and has the advantages of wide detection range, simple and convenient operation and high detection efficiency.

Of course, it is not necessary for any product in which the invention is practiced to achieve all of the above-described advantages at the same time.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a flow chart of a method for safely detecting the content of food preservative according to the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "opening," "upper," "lower," "thickness," "top," "middle," "length," "inner," "peripheral," and the like are used in an orientation or positional relationship that is merely for convenience in describing and simplifying the description, and do not indicate or imply that the referenced component or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be considered as limiting the present invention.

Referring to fig. 1, the present invention is a method for detecting the safety of the content of food preservatives, wherein the preservatives include dimethyl fumarate, dehydroacetic acid, benzoic acid, dimethyl paraben, diethyl paraben, and diisopropyl paraben; the method is characterized in that: the detection method comprises the following steps: step1, randomly sampling 5 different parts of the food to be detected, placing the parts into a test tube, injecting 10-20mL of hydrochloric acid solution into the test tube, shaking for 1-2min, and placing the test tube into a centrifuge for centrifugation for 3-5 min; the speed of centrifugation is 2000-3000 r/min; filtering after precipitation to obtain filtrate; step2, adding an adsorbent into the filtrate obtained in Step1, wherein the adsorbent is carbon nanofiber or graphene oxide; shaking for 2-5min, performing vortex analysis for 2-3 times with ethanol for 1-2min each time, mixing the solutions, blowing with nitrogen gas, and dissolving with ethanol to obtain sample solution; step 3: mixing the sample solution obtained in Step2 with a purifying agent for solid-liquid separation, and collecting supernatant; step 4: preparation of a standard mixed solution of preservatives: firstly, mixing preservative standard samples, dissolving the preservative standard samples in methanol to obtain preservative standard sample mixed stock solution, and then gradually diluting the preservative standard sample mixed stock solution by using methanol to obtain preservative standard mixed solution; step 5: taking 20 mu L of supernatant obtained in Step3 by using a pipette, injecting into a sample injection valve of a liquid chromatogram-mass spectrometer, and carrying out liquid chromatogram-mass spectrometer analysis to detect the type and content of the preservative; the liquid chromatography-mass spectrometer analysis in Step4 comprises gas chromatography detection parameters and mass spectrum detection conditions; the gas chromatography detection parameters comprise that the injection port temperature is 220 ℃, the column temperature is 80 ℃, the initial temperature is kept for 2min, the temperature is increased to 180 ℃ at the speed of 10 ℃/min, the temperature is increased to 240 ℃ at the speed of 15 ℃/min, and the temperature is kept for 14 min; carrier gas: helium with purity not less than 99.999% and flow rate 1.5 mL/min.

Example 1:

bread sample: randomly sampling 5 different parts of bread to be detected, placing the bread into a test tube, injecting 10-20mL of hydrochloric acid solution into the test tube, shaking for 1-2min, placing the test tube into a centrifuge for centrifuging for 3-5min, and filtering after precipitation to obtain filtrate; adding an adsorbent into the obtained filtrate, shaking for 2-5min, performing vortex analysis with ethanol for 2-3 times, each time for 1-2min, mixing the solutions, drying with nitrogen, and dissolving with ethanol to obtain a sample solution; mixing the obtained sample solution with a purifying agent for solid-liquid separation, and collecting supernatant; and (3) taking 20 mu L of supernatant by using a pipette, injecting the supernatant into a sample injection valve of a liquid chromatography-mass spectrometer, and carrying out liquid chromatography-mass spectrometer analysis to detect the type and the content of the preservative.

Example 2:

melon seed sample: randomly selecting 5 melon seeds from a batch of melon seeds, shelling the melon seeds to obtain shelled melon seeds, placing the shelled melon seeds into a test tube, injecting 10-20mL of hydrochloric acid solution into the test tube, shaking for 1-2min, placing the test tube into a centrifuge to centrifuge for 3-5min, and filtering after precipitation to obtain filtrate; adding an adsorbent into the obtained filtrate, shaking for 2-5min, performing vortex analysis with ethanol for 2-3 times, each time for 1-2min, mixing the solutions, drying with nitrogen, and dissolving with ethanol to obtain a sample solution; mixing the obtained sample solution with a purifying agent for solid-liquid separation, and collecting supernatant; and (3) taking 20 mu L of supernatant by using a pipette, injecting the supernatant into a sample injection valve of a liquid chromatography-mass spectrometer, and carrying out liquid chromatography-mass spectrometer analysis to detect the type and the content of the preservative.

In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.