阅读说明：本技术 一种食品中二氧化硫残留量的快速检测方法 (Method for rapidly detecting residual quantity of sulfur dioxide in food ) 是由 张雅莉 富玉 高俊海 于 2019-11-02 设计创作，主要内容包括：本发明公开了一种食品中二氧化硫残留量的快速检测方法,属于食品安全快速检测技术领域。试样经提取液提取,显色处理后,比照标准比色卡半定量二氧化硫残留量。该检测方法快速、便捷、操作简单,成本低,可以满足个体、企业、质监、工商等部门以及非专业人士的现场快速检测和实验室检测的需求。(The invention discloses a method for rapidly detecting the residual quantity of sulfur dioxide in food, and belongs to the technical field of rapid detection of food safety. And extracting the sample by using an extracting solution, and performing color development treatment, and then comparing the semi-quantitative sulfur dioxide residue with that of a standard colorimetric card. The detection method is rapid, convenient, simple to operate and low in cost, and can meet the requirements of on-site rapid detection and laboratory detection of individuals, enterprises, quality supervision, industrial and commercial departments and non-professionals.)

1. A method for rapidly detecting the residual quantity of sulfur dioxide in food is characterized by comprising the following steps: weighing 1g of a sample to be detected, adding 10mL of the extracting solution, uniformly mixing and standing for 5 min; 1mL of supernatant is taken, and a dichromate solution and a sulfuric acid solution are sequentially added and uniformly mixed; adding a diphenylcarbazide acetone solution, uniformly mixing and standing for 5-10 min; and semi-quantifying the residual quantity of the sulfur dioxide in the sample by comparing with a standard colorimetric card.

2. The method according to claim 1, wherein the extract is phosphate buffer with pH of 1.

3. The method for rapidly detecting the residual amount of sulfur dioxide in food according to claim 1, wherein the concentration of the dichromate solution is 0.25mmol/L, and the addition amount is 1 drop; the concentration of the sulfuric acid solution is 4.5mol/L, and the addition amount is 1 drop; the concentration of the dibenzoyl dihydrazido acetone solution is 5.16mmol/L, and the addition amount is 1 drop.

4. The method according to claim 1, wherein the standard colorimetric card is prepared by diluting 1mL of each of the solutions to a sulfite standard solution with a concentration of 0, 2, 5, 10, or 20mg/L, and treating the solution in the same pretreatment manner as the sample to show a color change from purple to colorless; the concentration is expressed in terms of sulfur dioxide.

Technical Field

The invention belongs to the technical field of rapid detection of food safety, relates to a rapid detection method of sulfur dioxide residue in food, and particularly relates to a rapid detection method of sulfur dioxide residue in semi-quantitative food by using a standard colorimetric card.

Background

Sulfur dioxide in food is commonly referred to as sulfur dioxide and inorganic sulfites capable of generating sulfur dioxide, and includes sulfur dioxide, potassium metabisulfite, sodium sulfite, sodium bisulfite, sodium hyposulfite, etc., and is a bleaching agent, preservative and antioxidant widely used in the food industry.

However, since the 80's of the 20 th century, the safety of sulfur dioxide in food products has attracted increasing attention. Sulfur dioxide and its derivatives are harmful to the respiratory system of humans, and also cause pathological changes in the brain, liver, spleen and kidney, and even to the reproductive system. Therefore, with the enhancement of food safety awareness of people and the increase of food safety monitoring strength in China, sulfur dioxide becomes one of important items for food safety detection.

The acid dichromate method has been used to determine the sulfur dioxide content of air, but is clearly not suitable for the detection of sulfur dioxide in food products based on this method. Therefore, the invention aims to establish a method for rapidly detecting the residual quantity of sulfur dioxide in semi-quantitative food by using a standard colorimetric card through innovative optimization by using the basic principle of determining sulfur dioxide by using an acid dichromate method.

Disclosure of Invention

The invention provides a method for rapidly detecting the residual quantity of sulfur dioxide in food, which utilizes a standard colorimetric card to rapidly and semi-quantitatively detect the sulfur dioxide in the food, and has the advantages of simple operation and low cost.

In order to achieve the purpose, the technical scheme adopted by the invention comprises the following steps: weighing 1g of a sample to be detected, adding 10mL of the extracting solution, uniformly mixing and standing for 5 min; 1mL of supernatant is taken, and a dichromate solution and a sulfuric acid solution are sequentially added and uniformly mixed; adding a diphenylcarbazide acetone solution, uniformly mixing and standing for 5-10 min; and semi-quantifying the residual quantity of the sulfur dioxide in the sample by comparing with a standard colorimetric card.

Preferably, the extract is a phosphate buffer at pH 1.

Preferably, the concentration of the dichromate solution is 0.25mmol/L, and the addition amount is 1 drop; the concentration of the sulfuric acid solution is 4.5mol/L, and the addition amount is 1 drop; the concentration of the dibenzoyl dihydrazido acetone solution is 5.16mmol/L, and the addition amount is 1 drop.

Preferably, the standard colorimetric card is prepared by taking 1mL of sulfite standard solution diluted by the extracting solution to be 0, 2, 5, 10 and 20mg/L, and treating the solution in the same pretreatment mode as the sample to change the purple color into colorless; wherein the concentration is measured as sulfur dioxide.

Has the advantages that: the invention relates to a method for rapidly detecting the residual quantity of sulfur dioxide in food, which comprises the steps of extracting a sample through an extracting solution, uniformly mixing and standing, adding a color developing agent into supernate for color development, and semiquantifying the sulfur dioxide content in the sample by using a standard colorimetric card. The detection method is rapid, convenient, simple to operate and low in cost, and can meet the requirements of on-site rapid detection and laboratory detection of individuals, enterprises, quality supervision, industrial and commercial departments and non-professionals.

Drawings

FIG. 1 is a standard colorimetric card

Wherein: 1. a colorimetric map; 2. the concentration of sulfur dioxide.

Detailed Description

The technical solutions of the present invention are described in detail below with reference to specific examples, but the following examples are only intended to illustrate the present invention in detail and do not limit the scope of the present invention in any way.

The reagents referred to in the following examples are all commercially available conventional reagents unless otherwise specified.