CN-116952910-B - Method for determining peroxide value in oil-and-fat-containing food

Abstract

The application belongs to the technical field of substances detected by utilizing optical means, and relates to a method for measuring peroxide value in oil-containing food. Aiming at the technical problems that the detection efficiency is low, the accuracy is low, and the detection personnel and the environment are not friendly in the detection method of the peroxide value of the oil-containing food in the prior art, the application provides the method capable of detecting the peroxide value of the oil-containing food, the iodine simple substance is dissolved into fatty amine and uniformly mixed, the iodine-doped carbon point is prepared, the iodine-doped carbon point is utilized to be reacted with fresh oil-containing food serving as a standard oil sample, finally, the iodine-doped carbon point is added into a sample to be detected for reaction, and the peroxide value is calculated through fluorescence intensity, so that the rapid and accurate detection of the peroxide value can be realized.

Inventors

• ZHENG LEI
• DONG BAOLEI
• LIU SHUAI
• QU HAO
• JIN LONG
• SUN MEI

Assignees

• 合肥工业大学
• 洽洽食品股份有限公司

Dates

Publication Date

20260512

Application Date

20230524

Claims (5)

1. 1. The method for measuring the peroxide value in the oil-and-fat-containing food is characterized by comprising the following steps: Preparing iodine doped carbon points, namely dissolving iodine simple substances into fatty amine, uniformly mixing to obtain precursor solution, and heating the precursor solution to obtain the iodine doped carbon points, wherein the fatty amine is one or more of octadecylamine, hexadecylamine, tetradecylamine and dodecylamine, the mass ratio of the iodine simple substances to the fatty amine in the precursor solution is 1:3-1:5, the heating temperature range of the precursor solution is 180-210 ℃, and the heating treatment time is 6-12 hours; Preparing a standard curve, namely taking fresh oil-containing food as a standard oil sample, uniformly mixing the standard oil sample with an organic solvent to prepare standard oil sample solutions with different peroxide value gradients, respectively adding the iodine-doped carbon dots into the standard oil sample solutions for reaction, detecting fluorescence signal intensity to obtain fluorescence signal data, taking the peroxide value of the standard oil sample solutions as an abscissa and taking the fluorescence signal data as an ordinate, establishing the standard curve, taking 365 nm as an excitation wavelength and 440 nm as an emission wavelength to measure the fluorescence signal intensity, drawing the standard curve, adding the iodine-doped carbon dots into the standard oil sample solutions, wherein the reaction parameters of the iodine-doped carbon dots are that the temperature is between room temperature and 100 ℃, the reaction time is between 10 and 60 minutes, diluting the prepared iodine-doped carbon dots by n-butyl alcohol for 200 times, and mixing the iodine-doped carbon dot solutions and the standard oil samples with different peroxide values in a ratio of 9:1; Pretreating the food containing the grease to be detected to obtain a sample to be detected; And adding the iodine-doped carbon point to the sample to be detected for reaction, and calculating the peroxide value in the oil-containing food through the standard curve.
2. 2. The method for measuring peroxide value in a fat-containing food according to claim 1, wherein the organic solvent is one or more of n-butanol, isopropanol, toluene and n-hexane.
3. 3. The method for measuring the peroxide value of a fat-containing food according to claim 2, wherein the fresh fat-containing food is subjected to a constant temperature treatment at a constant temperature of 60 ℃.
4. 4. The method for measuring peroxide value in a fat-containing food according to any one of claims 1 to 3, wherein the fat-containing food is a liquid, and wherein the fat-containing food is diluted with an organic solvent, wherein the organic solvent is one or more of n-butanol, isopropanol, toluene and n-hexane.
5. 5. A method for measuring peroxide value in a fat-containing food according to any one of claims 1 to 3, wherein the fat-containing food is solid, the fat-containing food is extracted by an extraction method using a nonpolar organic solvent, the nonpolar organic solvent is one or more of petroleum ether, hexane and toluene, and the mass ratio of the fat-containing food to the nonpolar organic solvent is 1:5 to 1:10.

Description

Method for determining peroxide value in oil-and-fat-containing food Technical Field The invention belongs to the technical field of substances detected by utilizing optical means, and particularly relates to a method for measuring peroxide value in oil-containing food. Background The oil-rich food such as oily nuts, vegetable oil, fried food, etc. is susceptible to oxidation rancidity due to temperature, light and air during storage and processing. During rancidity, triglycerides and fatty acids can be cleaved to produce peroxides, which further undergo oxidative decomposition to produce small molecule aldehydes, ketones, acids, and other compounds, severely affecting the quality and safety of foods. Peroxide can damage cell membrane structure, and long-term eating of food with peroxide value exceeding standard has great harm to human health. The peroxide value is thus used as an important indicator of how oxidized the fat-rich food is, and can be used to monitor food safety. The existing national standard adopts an iodine method and a potentiometric titration method to detect the peroxide value in food, and GB5009.227-2016 "determination of peroxide value in food safety national Standard food". The reaction mechanism is that in an acidic medium, peroxide and hydroperoxide formed in the oxidation and rancidity process of grease oxidize iodide ions into elemental iodine, then a starch standard solution is used as an indicator or a potentiometric titrator is used for determining a titration end point, a sodium thiosulfate standard solution is used for titration, and the peroxide value is calculated according to the amount of precipitated iodine. The conventional iodination method and potentiometric titration method have complex and tedious testing process, low detection sensitivity, incapability of real-time monitoring and low detection efficiency. Therefore, there is an urgent need for a more accurate and rapid detection method for monitoring the peroxide value of fat-rich foods. The fluorescence visual analysis has the characteristics of high sensitivity, high detection speed and the like, and has wide application prospect in various fields such as food safety monitoring, environment monitoring, clinical diagnosis and the like. Compared with the method of qualitative and quantitative analysis by means of color change such as the iodometry, the visual detection based on fluorescence signal change has the remarkable advantages of high sensitivity, obvious signal gradient change, less interference by external conditions and the like, and can realize the rapid and high-sensitivity detection of peroxide values in foods. For example, zhu and the like synthesize all-inorganic perovskite quantum dots CsPbX 3 (X is Cl, br and I), oxidation-reduction reaction is carried out by utilizing iodide ions and peroxide in Food and halogen exchange reaction of the perovskite quantum dots is combined, visual rapid detection of peroxide values in grease is realized (Anal. Chem.2019,91, 14183-14187), wu and the like synthesize fluorescent metal organic framework materials (Pb-MOF), the property that Pb-MOF can be quenched efficiently by utilizing iodide ions is utilized, oxidation-reduction reaction is carried out by combining the iodide ions and peroxide in Food, and visual rapid detection of peroxide values in grease is realized (Food chem.2022,385, 132710). For example, the publication number of Chinese patent application is CN110146496A, the application date is 2019, and the invention name is "a method for rapidly determining the peroxide value of edible oil", the disclosed method uses oleylamine iodine as a reducing agent of target peroxide, uses the fluorescent color of CsPbBr 3 perovskite nanocrystalline after halogen exchange as a visual indication mode of the peroxide degree of the edible oil, and uses molecular fluorescent detection as a detection method. Although the above scheme can realize rapid detection of peroxide value, synthesis of the used fluorescent signal probe materials such as perovskite quantum dots, metal organic frameworks and the like all require complex and harsh reaction conditions, and use raw materials containing heavy metal lead and consume a large amount of organic reagents. Therefore, a novel peroxide value detection method is explored, the sensitive and rapid detection of the peroxide value in the oil-and-fat-containing food is realized, and the method has important significance for guaranteeing the food safety. Disclosure of Invention 1. Problems to be solved Aiming at the technical problems that the fluorescent signal probe material used in the method for measuring the peroxide value in the fat-containing food in the prior art needs complex and harsh reaction conditions during synthesis, the detection steps are complicated, heavy metals are contained in the raw materials, the consumption of organic reagents is large, the detection efficiency is low, the accuracy is low, and the method is no