CN102323367A - Method for simultaneously determining contents of various preservatives in soy by capillary gas chromatography internal standard method - Google Patents
Method for simultaneously determining contents of various preservatives in soy by capillary gas chromatography internal standard method Download PDFInfo
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- CN102323367A CN102323367A CN201110140922A CN201110140922A CN102323367A CN 102323367 A CN102323367 A CN 102323367A CN 201110140922 A CN201110140922 A CN 201110140922A CN 201110140922 A CN201110140922 A CN 201110140922A CN 102323367 A CN102323367 A CN 102323367A
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Abstract
The invention discloses a method for simultaneously determining contents of various preservatives in soy by a capillary gas chromatography internal standard method, which comprises the following steps of: (1) weighing a soy sample; (2) adding an internal standard solution in the sample, and then sequentially being subjected to acidification, ether extraction, water removal water by purification and concentration treatment to obtain a sample solution; (3) taking the sample solution from the step (2) to be subjected to gas chromatography to obtain chromatographic data; and (4) comparing the chromatographic data obtained from the step (3) with the preset standard data of preservatives to obtain the contents of various preservatives in the soy. The method can simultaneously determine the contents of preservatives such as benzoic acid, sorbic acid, dehydroacetic acid and paraben esters and the like in the soy, is simple and convenient to operate, and is easy to implement, the impact of operation error, instrument conditions and other factors on determination results can be effectively reduced, and the results are accurate and reliable.
Description
Technical field
The present invention relates to a kind of method that detects various antiseptic contents in the soy sauce, especially a kind of capillary gas chromatography internal standard method is measured the method for various antiseptic contents in the soy sauce simultaneously.
Background technology
Soy sauce is a kind of flavouring that is rich in nutrition, delicious flavour; Possibly take place putrid and deteriorated when receiving contamination by micro; Therefore; Manufacturer can add some food antisepticses and suppress the corruption that possibly form, and antiseptic commonly used in soy sauce has benzoic acid, sorbic acid and parabens etc.National standard makes explicit provisions to limiting the quantity of of antiseptic, and in the safe handling scope, antiseptic is to the human non-toxic spinoff, but excessive eating has certain toxicity to human body.Relevant examination criteria is GB/T 5009.29-2003 " sorbic acid, benzoic mensuration in the food " and GB/T5009.31-2003 " mensuration of parabens in the food " at present; Carry out the mensuration of various antiseptic contents in the soy sauce if directly adopt standard method; One duplicate samples will be carried out pre-service respectively and adopt different instrument conditions with two kinds of methods, wastes time and energy.And through the practice discovery; When directly adopting this standard that the soy sauce series products is detected; Recovery of standard addition is lower, measures unstable result, and when comparatively dense thick dark soy sauce class sample is extracted, also carries out subsequent operation because of the layering that is difficult to of emulsion easily.Therefore directly when adopting vapor-phase chromatography in this standard particularly dark soy sauce class sample detecting to the soy sauce series products; Precision and accuracy are all not ideal enough; This is owing to adopt external standard method quantitative, is the generation that sample preparation or instrument condition all possibly cause error, and loaded down with trivial details determination step has increased the occurrence probability of operate miss; Last machine is measured requirement especially must have quite high instrument performance and configuration, for example need dispose automatic sampler and guarantee accurately to control sample size etc.
Summary of the invention
For having overcome the deficiency of prior art; The invention provides a kind of capillary gas chromatography internal standard method and measure the method for various antiseptic contents in the soy sauce simultaneously; This method can be measured the content of the antiseptics such as benzoic acid, sorbic acid, dehydroactic acid and parabens in the soy sauce simultaneously; Easy to operation, the factors such as operate miss and instrument condition that can effectively reduce are to measuring result's influence, and the result accurately and reliably.
The objective of the invention is to realize through following technical measures: a kind of capillary gas chromatography internal standard method is measured the method for various antiseptic contents in the soy sauce simultaneously, and it may further comprise the steps:
(1) takes by weighing soy sample;
(2) in sample, add internal standard substance solution, carry out acidifying, extracted by ether then successively, purification dewaters and concentration, obtains sample solution;
(3) sample solution of getting in the step (2) carries out gas chromatographic analysis, obtains chromatogram analysis data;
(4), obtain the content of various antiseptics in the soy sauce with the chromatogram analysis data and the comparison of predetermined antiseptic normal data of the acquisition of step (3).
Can take by weighing the consumption of described soy sample in the step of the present invention (1) according to different soy sauce classifications.Wherein, light soy sauce class soy sauce recommends the amount of taking by weighing between 0.5～2.5g.
Because when dark soy sauce class soy sauce adopts extracted by ether; Be prone to emulsification; Cause to reach the purpose of effective extraction antiseptic; Thereby when in step of the present invention (1), being dark soy sauce class soy sauce, need carry out pre-service: in dark soy sauce class soy sample, add 1～2.5 times of sodium chloride solution dilution to dark soy sauce class soy sauce like sample.
Step of the present invention (2) recommends to use following concrete operations: soy sample is placed tool plug container; Accurately add 0.3～0.7ml inner mark solution, add 0.3～0.7ml hydrochloric acid solution again, mixing; Divide 2 extractions with 20～40ml ether, merge upper solution twice; Add 3～5ml sodium bisulfate, washing, purifying is removed lower floor's solution then, in upper solution, adds then after 3～7g anhydrous sodium sulfate dewaters, and nitrogen flushing concentrates, and uses acetone diluted again, and is subsequent use.
Described tool plug container can adopt tool plug graduated cylinder, tool plug test tube or color comparison tube.
The chromatographic condition that step of the present invention (3) is recommended is: described capillary chromatographic column adopts polarity capillary chromatographic column or nonpolar capillary chromatographic column, and requirement can realize good separation simultaneously to each component to be measured and internal standard compound matter; Constant temperature (about 200～220 ℃ of column temperature) or suitable temperature programme all can; Constant current or constant voltage all can, manually or auto injection all can, carrier gas is a high pure nitrogen.
Described polarity capillary chromatographic column can adopt HP-20M, DB-WAX or PEG-20M etc., and length is more than 30m.
Described in the present invention internal standard substance solution recommends to adopt the acetone soln of fatty acid ester, marks peak position between component peaks to be measured in requiring, and does not have to cover.Select for use the acetone soln of Ester to make interior mark, under refrigerated condition, can preserve the long period and never degenerate than more stable with acid.The acetone soln concentration of described fatty acid ester is between 2～3g/L.Described fatty acid ester can be that carbon number is 16～24 the fatty acid methyl ester or the acetone soln of other ester class,
Predetermined antiseptic normal data is the series standard solution through the various preservative component to be measured of using the 0.1～2.0g/L that is added with internal standard substance solution in the step according to the invention (4), under the GC conditions of setting, records the correction factor of antiseptic.
Ether of the present invention must pass through the liquor kalii iodide inspection, must not contain superoxide, otherwise it is on the low side to cause sorbic acid to measure the result easily.
The invention has the advantages that: adopt internal standard method; Effectively reduced the error that the various factorss such as concentration because of sample size, solvent loss, testing sample cause; Even slightly changing, condition determination can not exert an influence to the result yet; If adopt external standard method quantitative, then very high to the requirement of instrument apparatus and personnel operation.This method is easy and simple to handle, utilizes general detecting instrument and apparatus, just can obtain comparatively desirable mensuration result, and the sample pretreatment time also shortens than standard method greatly, and cost is relatively low, is easy to promote.And the condition that polar stationary phase constant temperature separates can also be used for the fatty acid of edible vegetable oil is formed conventional analysis, can on same instrument, realize the alternately mensuration to two test items, improved the utilization factor of instrument.
Description of drawings:
Fig. 1 is the capillary gas chromatography chromatogram of the embodiment of the invention one.
Fig. 2 is the capillary gas chromatography chromatogram of the embodiment of the invention two.
Embodiment
In order to understand essence of an invention better, specify the technology contents of invention below with embodiment, but content of the present invention is not limited thereto.
Embodiment one
1. chromatographic condition:
The gas chromatograph of configuration fid detector;
Capillary chromatographic column is DB-WAX (30m * 0.32mm * 0.25 μ m)
210 ℃ of column temperatures, vaporizer and sensing chamber are 230 ℃
Hand sampling 1.0 μ l
Carrier gas is a high pure nitrogen, and column cap is pressed 0.07Mpa, split ratio 100: 1
2. correction factor is measured
Preparing standard solution: accurately take by weighing benzoic acid, each 0.2g of sorbic acid, with acetone solution and be settled to 100ml;
Preparation inner mark solution: accurately take by weighing methyl margarate 0.2g, with acetone solution and be settled to 100ml;
The preparation standard is used solution: get an amount of standard solution and mix with inner mark solution, interior mark concentration is 0.4g/L, and standard substance concentration then is respectively 0.2,0.4,0.6,0.8,1.0g/L.
Under above-mentioned chromatographic condition, use the solution sample introduction with series standard, with peak area ratio and concentration ratio drawing standard curve, obtain the correction factor of benzoic acid and sorbic acid, set up corresponding interior mark analytical approach.
3. sample preparation
Take by weighing dark soy sauce sample 1.0g, be accurate to 0.001g, add 1.5g sodium chloride solution (200g/L) again; Place 25ml tool plug test tube, accurately add the 0.5ml inner mark solution, add 0.5ml hydrochloric acid solution (1+1) again; Mixing; Divide 2 extractions with the 30ml ether, each jolting 1min incorporates upper solution in another 50ml tool plug test tube into.Add 4ml sodium bisulfate (20g/L), the 1min that fully vibrates absorbs lower floor with sharp mouth suction pipe, repeats this step once.Add the 5g anhydrous sodium sulfate, fully vibration in solution impouring round-bottomed flask, places that nitrogen flushing is concentrated into about 0.5ml in 45 ℃ of water-baths, adds 2.0ml acetone along wall, moves in the 2ml sample bottle, keeps supplying machine usefulness.
4. sample determination
Using under the identical chromatographic condition of solution with standard, choosing corresponding interior mark analytical approach, sample introduction is measured, and reads the mensuration result from chromatographic work station, and is as shown in Figure 1.
Embodiment two
1. chromatographic condition:
The gas chromatograph of configuration fid detector;
Capillary chromatographic column is DB-WAX (30m * 0.32mm * 0.25 μ m)
210 ℃ of column temperatures, vaporizer is 230 ℃ with detecting room temperature
Hand sampling 0.5 μ l
Carrier gas is a high pure nitrogen, and column cap is pressed 0.07Mpa, split ratio 100: 1
2. correction factor is measured
Preparing standard solution: accurately take by weighing benzoic acid, sorbic acid, dehydroactic acid, methyl p-hydroxybenzoate, ethyl-para-hydroxybenzoate, each 0.2g of propylparaben, with acetone solution and be settled to 100ml;
Preparation inner mark solution: accurately take by weighing methyl margarate 0.2g, with acetone solution and be settled to 100ml;
The preparation standard is used solution: get an amount of standard solution and mix with inner mark solution; Interior mark concentration is 0.4g/L; The concentration of benzoic acid and sorbic acid then is respectively 0.2,0.4,0.6,0.8,1.0g/L, and the concentration of methyl p-hydroxybenzoate, ethyl-para-hydroxybenzoate, propylparaben then is respectively 0.05,0.1,0.15,0.2,0.25g/L.
Under above-mentioned chromatographic condition; Use the solution sample introduction with series standard; With peak area ratio and concentration ratio drawing standard curve, obtain the correction factor of benzoic acid, sorbic acid, methyl p-hydroxybenzoate, ethyl-para-hydroxybenzoate, propylparaben, set up corresponding interior mark analytical approach.
3. sample preparation
Take by weighing light soy sauce sample 2.5g, be accurate to 0.001g, place 25ml tool plug test tube; Accurately add the 0.5ml inner mark solution, add 0.5ml hydrochloric acid solution (1+1) again, mixing; Divide 2 extractions with the 25ml ether, each jolting 1min incorporates upper solution in another 50ml tool plug test tube into.Add 5ml sodium bisulfate (20g/L), the 1min that fully vibrates absorbs lower floor with sharp mouth suction pipe, repeats this step once.Add the 5g anhydrous sodium sulfate, fully vibration in solution impouring round-bottomed flask, places that nitrogen flushing is concentrated into about 0.5ml in 45 ℃ of water-baths, adds 2.0ml acetone along wall, moves in the 2ml sample bottle, keeps supplying machine usefulness.
4. sample determination
Using under the identical chromatographic condition of solution with standard, choosing corresponding interior mark analytical approach, sample introduction is measured, and reads the mensuration result from chromatographic work station, and is as shown in Figure 2.
More than method provided by the present invention has been carried out detailed introduction, used concrete example among this paper principle of the present invention and embodiment set forth, the explanation of above embodiment just is used for helping to understand method of the present invention and core concept thereof; Simultaneously, for one of ordinary skill in the art, according to thought of the present invention, the part that on embodiment and range of application, all can change, in sum, this description should not be construed as limitation of the present invention.
Claims (10)
1. a capillary gas chromatography internal standard method is measured the method for various antiseptic contents in the soy sauce simultaneously, it is characterized in that it may further comprise the steps:
(1) takes by weighing soy sample;
(2) in sample, add internal standard substance solution, carry out acidifying, extracted by ether then successively, purification dewaters and concentration, obtains sample solution;
(3) sample solution of getting in the step (2) carries out gas chromatographic analysis, obtains chromatogram analysis data;
(4), obtain the content of various antiseptics in the soy sauce with the chromatogram analysis data and the comparison of predetermined antiseptic normal data of the acquisition of step (3).
2. capillary gas chromatography internal standard method according to claim 1 is measured the method for various antiseptic contents in the soy sauce simultaneously, it is characterized in that, takes by weighing the consumption of described soy sample in the described step (1) according to different soy sauce classifications.
3. capillary gas chromatography internal standard method according to claim 1 is measured the method for various antiseptic contents in the soy sauce simultaneously, it is characterized in that, when the soy sauce in the described step (1) is dark soy sauce class soy sauce, needs dark soy sauce class soy sauce is carried out pre-service.
4. capillary gas chromatography internal standard method according to claim 3 is measured the method for various antiseptic contents in the soy sauce simultaneously, it is characterized in that, described pre-service is: in dark soy sauce class soy sample, add 1～2.5 times of sodium chloride solution dilution.
5. capillary gas chromatography internal standard method according to claim 1 is measured the method for various antiseptic contents in the soy sauce simultaneously; It is characterized in that the concrete operations of described step (2): soy sample is placed tool plug container, accurately add 0.3～0.7ml inner mark solution; Add 0.3～0.7ml hydrochloric acid solution again; Mixing divides 2 extractions with 20～40ml ether, merges upper solution twice; Add 3～5ml sodium bisulfate, washing, purifying is removed lower floor's solution then, in upper solution, adds then after 3～7g anhydrous sodium sulfate dewaters, and nitrogen flushing concentrates, and uses acetone diluted again, and is subsequent use.
6. capillary gas chromatography internal standard method according to claim 1 is measured the method for various antiseptic contents in the soy sauce simultaneously; It is characterized in that; The chromatographic condition of described step (3) is: described capillary chromatographic column adopts polarity capillary chromatographic column or nonpolar capillary chromatographic column, and requirement can realize good separation simultaneously to each component to be measured and internal standard compound matter; Constant temperature or suitable temperature programme; Constant current or constant voltage, manual or auto injection, carrier gas is a high pure nitrogen.
7. capillary gas chromatography internal standard method according to claim 6 is measured the method for various antiseptic contents in the soy sauce simultaneously, it is characterized in that, described polarity capillary chromatographic column adopts HP-20M, DB-WAX or PEG-20M, and length is more than 30m.
8. capillary gas chromatography internal standard method according to claim 1 is measured the method for various antiseptic contents in the soy sauce simultaneously, it is characterized in that, the internal standard substance solution in the described step (2) adopts the acetone soln of fatty acid ester.
9. capillary gas chromatography internal standard method according to claim 8 is measured the method for various antiseptic contents in the soy sauce simultaneously, it is characterized in that, the acetone soln concentration of described fatty acid ester is between 2～3g/L.
10. capillary gas chromatography internal standard method according to claim 8 is measured the method for various antiseptic contents in the soy sauce simultaneously, it is characterized in that, described fatty acid ester is that carbon number is 16～24 fatty acid methyl ester.
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| CN201110140922A CN102323367A (en) | 2011-05-27 | 2011-05-27 | Method for simultaneously determining contents of various preservatives in soy by capillary gas chromatography internal standard method |
| CN201210165411.7A CN102707002B (en) | 2011-05-27 | 2012-05-25 | The method of various antiseptic content in capillary gas chromatography internal standard method Simultaneously test soy sauce |
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| CN102662009A (en) * | 2012-04-25 | 2012-09-12 | 辽宁省食品药品检验所 | Method for quickly determining content of additive of plurality of types in food |
| CN102998389A (en) * | 2012-11-23 | 2013-03-27 | 浙江赞宇科技股份有限公司 | Gas chromatography detection method of corrosion removers in food |
| CN103076407A (en) * | 2012-12-26 | 2013-05-01 | 通标标准技术服务有限公司 | Fast detection method for food preservative agent and antioxidant |
| CN103134870A (en) * | 2013-02-01 | 2013-06-05 | 浙江工业大学 | Method for measuring sorbic acid and benzoic acid in foodstuff |
| CN103743831A (en) * | 2013-12-21 | 2014-04-23 | 广西科技大学 | Method for detecting sorbic acid serving as food preservative |
| CN103760249A (en) * | 2013-12-23 | 2014-04-30 | 广西科技大学 | Detection method of deoxidation acetic acids of food antiseptics |
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| KR100942314B1 (en) * | 2009-03-18 | 2010-02-17 | 대한민국 | Measurement method for purity of didecyl-dimethyl-ammonium chloride using hplc-ms |
| CN101526509B (en) * | 2009-05-04 | 2012-11-21 | 佛山市海天调味食品股份有限公司 | Method for rapidly determining content of preservatives in condiment |
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| CN102662009A (en) * | 2012-04-25 | 2012-09-12 | 辽宁省食品药品检验所 | Method for quickly determining content of additive of plurality of types in food |
| CN102662009B (en) * | 2012-04-25 | 2014-02-26 | 辽宁省食品药品检验所 | Method for quickly determining content of additive of plurality of types in food |
| CN102998389A (en) * | 2012-11-23 | 2013-03-27 | 浙江赞宇科技股份有限公司 | Gas chromatography detection method of corrosion removers in food |
| CN102998389B (en) * | 2012-11-23 | 2014-07-09 | 浙江赞宇科技股份有限公司 | Gas chromatography detection method of corrosion removers in food |
| CN103076407A (en) * | 2012-12-26 | 2013-05-01 | 通标标准技术服务有限公司 | Fast detection method for food preservative agent and antioxidant |
| CN103076407B (en) * | 2012-12-26 | 2014-07-09 | 通标标准技术服务有限公司 | Fast detection method for food preservative agent and antioxidant |
| CN103134870A (en) * | 2013-02-01 | 2013-06-05 | 浙江工业大学 | Method for measuring sorbic acid and benzoic acid in foodstuff |
| CN103134870B (en) * | 2013-02-01 | 2014-09-03 | 浙江工业大学 | Method for measuring sorbic acid and benzoic acid in foodstuff |
| CN103743831A (en) * | 2013-12-21 | 2014-04-23 | 广西科技大学 | Method for detecting sorbic acid serving as food preservative |
| CN103760249A (en) * | 2013-12-23 | 2014-04-30 | 广西科技大学 | Detection method of deoxidation acetic acids of food antiseptics |
| CN106404936A (en) * | 2016-08-25 | 2017-02-15 | 宁波检验检疫科学技术研究院 | Method used for detecting pentyl p-hydroxybenzoate in washing products |
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| CN102707002A (en) | 2012-10-03 |
| CN102707002B (en) | 2015-08-05 |
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