CN108489975A - A kind of accurate detection method of cassava HCN content simple and fasts - Google Patents
A kind of accurate detection method of cassava HCN content simple and fasts Download PDFInfo
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- CN108489975A CN108489975A CN201810212391.1A CN201810212391A CN108489975A CN 108489975 A CN108489975 A CN 108489975A CN 201810212391 A CN201810212391 A CN 201810212391A CN 108489975 A CN108489975 A CN 108489975A
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Abstract
The invention discloses a kind of accurate detection methods of cassava HCN content simple and fasts, take isometric NaCO3Picrate mixed liquor is made with picric acid, filter paper item immersion picrate mixed liquor is impregnated with；Equal 5min, the filter paper item for being soaked with mixed liquor is pressed from both sides out, is placed on blotting paper and is removed extra mixed liquor；It weighs tapioca root sample and is put into test tube bottom, toluene is measured to instill on the tapioca root sample of test tube bottom, the filter paper item for being soaked with picrate mixed liquor is placed on test tube mouth, with rubber stopper seal, it is put into incubator and cultivates, card is compared by color standard after the completion of culture and identification is compared, obtain tapioca root HCN contents.The present invention provides a kind of methods that can accurately detect tapioca root hydrogen cyanide content in a short time, and this method is simple and convenient, operability is strong, improves work efficiency.
Description
Technical field
The invention belongs to tapioca root detection technique fields, and in particular to a kind of cassava HCN content simple and fasts are accurate
Detection method.
Background technology
Cassava (ManihotesculentaCrantz) is that Euphorbiaceae (Euphorbiaceae) cassava (Manihot) is planted
Object, drought-enduring anti-barren, plantation extensively is known as " king of starch " in more than 100 a countries and regions such as Africa, America and Asia,
It is the grain that nearly 600,000,000 people in the world depends on for existence.Cassava is widely used, in addition to making grain, is also important the raw material of industry, such as wood
Potato wedge root starch, dry plate can converted starch, alcohol and sorbierite processed etc., and these products are food, medicine, weaving, papermaking
Etc. industries important source material.
Since content of starch is higher in tapioca root, account for about 70%, and the digestibility of starch is higher than cornstarch, per mu yield
Amount is 4 times of corn, cheap, and therefore, many country's researchs use cassava as animal and fowl fodder raw material, to supplement the energy such as corn
Measure the deficiency (Zhao Junming, 2010) of diet.Contain natural lactic acid bacteria and saccharomycete in cassava, is conducive to keep just in animal intestinal tract
Normal colony balance reduces case fatality rate, and reduce the stink and fly quantity of feed lot to reduce the generation of epidemic disease.But
Contain cyanogen glycosides in Manihot Esculenta, hydrolyzable is at extremely toxic substance hydrogen cyanide under the action of enzyme for cyanogen glycosides, so the cassava that feeding is fresh
Root tuber has to, by detoxification treatment, it is even dead otherwise to easily cause animal poisoning.
Currently, there are two types of China's cassava HCN detection method of content：Mercuric nitrate or silver nitrate titration method, pyridine benzidine ratio
Color method, and pyridine benzidine colorimetric method is suitable only for micro HCN, wherein mercuric nitrate or silver nitrate titration method specific steps are such as
Under：
Testing principle is：Cassava is immersed in the water, is allowed to ferment, hydrogen cyanide is precipitated, can obtain containing the water-soluble of hydrogen cyanide
Liquid.This solution is passed through steamed and distillates hydrogen cyanide, the hydrogen cyanide distilled is absorbed with excessive nitric acid mercury standard solution, most
Redundant nitric acid mercury is titrated with the potassium rhodanate demarcated afterwards, by the difference of mercuric nitrate dosage and remaining mercuric nitrate, you can calculate sample
In hydrogen cyanide content, chemical reaction it is as follows：
Hg(NO3)2+2HCN→Hg(CN2)+2HNO3
Hg(NO3)2+2KSCN→Hg(CNS)2+2KNO3
Detecting step：(1) accurately weigh cassava meat 50g (or 10~15g of cassava skin), after grinding, about with 100~
150ml distilled water washes in the round-bottomed flask of 500ml, beyond the Great Wall bottle stopper, and 6h is placed at 30~35 DEG C, the work through cassava glucosidase
With cassava glycocide containing cyanogen is hydrolyzed to dextrose, acetone and hydrogen cyanide.
(2) will hydrolysis gained solution containing hydrogen cyanide, be passed through steam distillation, distillate is passed through to be added in advance
In the mercuric nitrate titer of 25ml0.007500mol/L (cassava skin should use 50ml), hydrogen cyanide is made to be fully absorbed (mercuric nitrate
Liquid answers pre-add 4mol/L nitric acid 1ml, makes in acidity), distillate can stop distilling after about collecting 200ml.
(3) in the distillate containing mercuric nitrate, add 40% ferriammonium sulfate { NH4Fe (SO4) 2.12H2O } indicator 2ml, then
Remaining mercuric nitrate in distillate is titrated with the potassium thiocyanate solution of standard 0.01500mol/L, until solution is in faint yellow.
It such as without mercuric nitrate, then can be used silver nitrate to replace, but potassium rhodanide titration end-point is not easy to find out, therefore ferriammonium sulfate instruction need to be added
Agent can just find out titration end-point.
As a result it calculates：The above results are substituted into following formula, the hydrogen cyanide content in cassava sample can be calculated：
HCN contents={ (V1-V2) xCx27x100 }/mx100%
V1-titrates 25ml (or 50ml) Hg (NO with KCNS in formula3)2When the volume (ml) that consumes
V2-titration residue Hg (NO3)2When the volume (ml) that consumes
The concentration (mol/L) of C-standard K CNS
The molal weight (g/mol) of 27-HCN
Pyridine benzidine colorimetric method be suitable only for HCN contents it is less when, be just not listed here, pyridine benzidine
Colorimetric method is the same cumbersome with mercuric nitrate or silver nitrate titration method step.
It can be seen from the above, the time that current China is all comparatively laborious, required about the method for detection tapioca root HCN contents
Long, cost is higher, but in relation to the method rare report of fast and accurately detection tapioca root HCN contents.
Invention content
It is an object of the invention to：For above-mentioned deficiency, the present invention provides providing, one kind is simple and convenient, can grasp
The strong tapioca root HCN detection methods of the property made, can detect the content of tapioca root hydrogen cyanide, improve work in a short time
Efficiency.
To achieve the goals above, the technical solution adopted by the present invention is as follows：
A kind of accurate detection method of cassava HCN content simple and fasts, described detection method includes the following steps：
(1) isometric 2.5% NaCO3 and 0.5% picric acid are taken, is uniformly mixed and picrate mixed liquor is made, it will
Filter paper item immerses in picrate mixed liquor and timing, and filter paper item is made to be impregnated with；
(2) after waiting for 5min, the filter paper item for being soaked with mixed liquor is pressed from both sides out, is placed on blotting paper and removes extra mixed liquor
It goes, it is spare；
(3) it weighs tapioca root sample and is put into test tube bottom, measure the cassava that 200~250ul toluene instills test tube bottom
On root tuber sample, the filter paper item that step (2) is soaked with to picrate mixed liquor is placed on test tube mouth, then with rubber stopper by test tube mouth
Sealing；
(4) test tube that step (3) is sealed is put into incubator and is cultivated, cultivation temperature is 26~28 DEG C, incubation time
For 2.5~3.0h, card is compared by color standard after the completion of culture and identification is compared, obtain tapioca root HCN contents.
Preferably, in step (3), the tapioca root sample is derived from nearly central part in the middle part of tapioca root.
Preferably, in step (3), the size of the tapioca root sample is：1cm×1cm×1cm.
Preferably, in step (4), the cassava HCN color standards colorimetric card (mg/kg) is as shown in table 1：
Table 1
| <10 | Glassy yellow |
| 10-20 | Yellow-buff |
| 20-30 | Buff-husky of common dye color |
| 30-50 | Husky of common dye color-rheum officinale |
| 50-100 | Rheum officinale-the colour of loess |
| 100-200 | The shallow Exocarpium Citri Rubrum of the colour of loess- |
| 200-400 | Shallow Exocarpium Citri Rubrum-autumn Exocarpium Citri Rubrum |
| 400-800 | Autumn Exocarpium Citri Rubrum-bronzing |
In conclusion the present invention is as the above scheme is adopted, the present invention has the positive effect that：The present invention provides
A kind of method that can accurately detect tapioca root hydrogen cyanide content in a short time, this method is simple and convenient, operability
By force, it improves work efficiency.This detection method handles simple, easy to operate, at low cost, 95% or more rate of accuracy reached, preferred embodiment
Accuracy rate can meet the routine testing needs of cassava hydrogen cyanide content up to 99% or more.
Specific implementation mode
Below in conjunction with the embodiment of the present invention, technical scheme in the embodiment of the invention is clearly and completely described,
Obviously, described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.Based in the present invention
Embodiment, every other embodiment obtained by those of ordinary skill in the art without making creative efforts, all
Belong to the scope of protection of the invention.
Embodiment 1
A kind of accurate detection method of cassava HCN content simple and fasts, described detection method includes the following steps：
(1) 2.5% isometric NaCO is taken3With 0.5% picric acid, it is uniformly mixed and picrate mixed liquor is made, it will
Filter paper item immerses in picrate mixed liquor and timing, and filter paper item is made to be impregnated with；
(2) after waiting for 5min, the filter paper item for being soaked with mixed liquor is pressed from both sides out, is placed on blotting paper and removes extra mixed liquor
It goes, it is spare；
(3) it weighs about 1cm × 1cm × 1cm (1g or so) fritter tapioca root sample and is put into test tube bottom, measure 200~
250ul toluene instills on the tapioca root sample of test tube bottom, and the filter paper item that step (2) is soaked with to picrate mixed liquor is placed on
Then test tube mouth will try ferrule with rubber stopper；The tapioca root sample is derived from nearly central part in the middle part of tapioca root；
(4) test tube that step (3) is sealed is put into incubator and is cultivated, cultivation temperature is 28 DEG C, and incubation time is
3.0h compares card by color standard after the completion of culture and identification is compared, and testing result is as shown in table 2.
Table 2
In order to better illustrate the method for detecting tapioca root HCN contents of the present invention, have simple and convenient, quick, accurate
Really, the strong advantage of feasibility makees following experiment.
1, the time measured needed for HCN contents is probed under different temperatures
Experiment process：Take 2.5% isometric NaCO3It is mixed with 0.5% picric acid and picrate mixed liquor is made, it will
Filter paper item is immersed in picrate mixed liquor and is impregnated with；The filter paper item for being soaked with mixed liquor is pressed from both sides out after 5min, being placed on blotting paper will
Extra mixed liquor is for use after removing.Weigh 1g or so (about 1cm × 1cm × 1cm fritters) tapioca root (nearly central part in middle part
Position) sample, it is put into test tube bottom, the toluene for measuring 200~250ul instills on the sample to be tested of test tube bottom.Bitter taste will be soaked with
Hydrochlorate mixed liquor filter paper item is placed on nozzle, is respectively placed in the detection institute that HCN contents are carried out at a temperature of 18 DEG C, 23 DEG C, 28 DEG C, 30 DEG C
It takes time.HCN contents required time is measured under different temperatures, and the results are shown in Table 3.
Table 3
By 3 experimental data of table it is found that when cultivation temperature is 28~30 DEG C, detection tapioca root HCN contents reach standard value
The required time is most short, but due to adding toluene in experimentation, the excessively high toluene of temperature can volatilize, be unfavorable for testing into
Row, the time measured needed for HCN contents at 26~28 DEG C are most short.
2, tapioca root HCN contents under the different disposal time are probed into
Experiment process：Take 2.5% isometric NaCO3It is mixed with 0.5% picric acid and picrate mixed liquor is made, it will
The filter paper of 1cm*6cm long is immersed in picrate mixed liquor and is impregnated with；The filter paper item for being soaked with mixed liquor is pressed from both sides out, is placed on blotting paper
It is for use after extra mixed liquor is removed.Weigh 1g or so (about 1cm × 1cm × 1cm fritters) tapioca roots (nearly center in middle part
Position) sample, it is put into test tube bottom after sample is shredded, after 200~250ul toluene is added, picrate mixed liquor will be soaked with
Filter paper item is placed on nozzle, after test tube is sealed with rubber stopper, be placed at a temperature of 28 DEG C handle respectively 0.5h, 1.5h, 2.0h,
2.5h, 3.0h, 3.5h, 4.0h observe the content of tapioca root HCN under different detection times.Cassava block under the different disposal time
The testing result of root HCN contents is as shown in table 4.
Table 4
By 4 experimental data of table it is found that detection tapioca root HCN contents reach the Best Times needed for standard value be 2.5~
3.0h, overlong time or the too short HCN contents detected are inaccurate.
3, the measurement of different tapioca root position HCN contents is probed into
Experiment process：Take 2.5% isometric NaCO3It is mixed with 0.5% picric acid and picrate mixed liquor is made, it will
The filter paper of 1cm*6cm long is immersed in picrate mixed liquor and is impregnated with；The filter paper item for being soaked with mixed liquor is pressed from both sides out, is placed on blotting paper
It is for use after extra mixed liquor is removed.Weigh the sample of 1g or so (about 1cm × 1cm × 1cm fritters) tapioca root different parts
Sheath portion, tapioca root middle part nearly central part, tapioca root head center part, wood in the middle part of product, respectively tapioca root
Potato wedge root tail portion central part.It is put into test tube bottom after sample is shredded, after 200~250ul toluene is added, picric acid will be soaked with
Salt mixed liquor filter paper item is placed on nozzle, is put into after being sealed test tube with rubber stopper after 28 DEG C of incubator 3.0h by color standard ratio
Card is compared.The testing result of different tapioca root position HCN contents is as shown in table 5.
Table 5
By 5 experimental data of table it is found that the measurement of tapioca root different parts HCN contents, takes nearly center in the middle part of tapioca root
Part, the data measured are closest to the content of tapioca root HCN.
In conclusion can accurately detect tapioca root hydrogen cyanide content in a short time the present invention provides a kind of
Method, this method is simple and convenient, operability is strong, improves work efficiency.This detection method handles simple, easy to operate, cost
Low, 95% or more rate of accuracy reached, preferred embodiment accuracy rate can meet the routine testing of cassava hydrogen cyanide content up to 99% or more
It needs.
It is obvious to a person skilled in the art that invention is not limited to the details of the above exemplary embodiments, Er Qie
In the case of without departing from spirit or essential attributes of the invention, the present invention can be realized in other specific forms.Therefore, nothing
By from the point of view of which point, the present embodiments are to be considered as illustrative and not restrictive, although this specification is according to reality
It applies example to be described, every embodiment includes only a single technical solution, this narrating mode of specification
It is merely for the sake of clarity, the skilled in the art should refer to the specification as a whole, the technical solutions in the embodiments
It may also be suitably combined to form that other embodiments which can be understood by those skilled in the art.
Claims (4)
1. a kind of accurate detection method of cassava HCN content simple and fasts, it is characterised in that：The detection method includes following step
Suddenly：
（1）Take 2.5% isometric NaCO3With 0.5% picric acid, it is uniformly mixed and picrate mixed liquor is made, filter paper item is soaked
Enter simultaneously timing in picrate mixed liquor, filter paper item is made to be impregnated with；
（2）After waiting for 5min, the filter paper item for being soaked with mixed liquor is pressed from both sides out, is placed on blotting paper and removes extra mixed liquor, it is standby
With；
（3）It weighs tapioca root sample and is put into test tube bottom, measure the tapioca root that 200~250ul toluene instills test tube bottom
On sample, by step（2）The filter paper item for being soaked with picrate mixed liquor is placed on test tube mouth, then with rubber stopper that test tube mouth is close
Envelope；
（4）By step（3）The test tube being sealed, which is put into incubator, to be cultivated, and cultivation temperature is 26~28 DEG C, incubation time 2.5
~3.0h compares card by color standard after the completion of culture and identification is compared, obtains tapioca root HCN contents.
2. a kind of accurate detection method of cassava HCN content simple and fasts according to claim 1, it is characterised in that：
Step（3）, the tapioca root sample is derived from nearly central part in the middle part of tapioca root.
3. a kind of accurate detection method of cassava HCN content simple and fasts according to claim 1, it is characterised in that：
Step（3）, the size of the tapioca root sample is：1cm×1cm×1cm.
4. a kind of accurate detection method of cassava HCN content simple and fasts according to claim 1, it is characterised in that：
Step（4）, the cassava HCN color standard colorimetric cards are：<10, it is in glassy yellow；10-20 is in yellow or buff；20-30,
In buff or husky of common dye color；30-50 is in husky of common dye color or rheum officinale；50-100 is in rheum officinale or the colour of loess；100-200 is in the colour of loess or shallow
Exocarpium Citri Rubrum；200-400 is in shallow Exocarpium Citri Rubrum or autumn Exocarpium Citri Rubrum；400-800 is in autumn Exocarpium Citri Rubrum or bronzing.
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| JP6117009B2 (en) * | 2013-06-12 | 2017-04-19 | 鹿島建設株式会社 | Cyan density measurement method |
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2018
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|---|---|---|---|---|
| US20080280372A1 (en) * | 2007-05-11 | 2008-11-13 | Walker Jeremy P | Continuous monitor for cyanide and cyanogen blood agent detection in water |
| CN202433306U (en) * | 2011-12-16 | 2012-09-12 | 江苏警官学院 | Toxic gas safety test box in tank and pipeline |
| CN203502354U (en) * | 2013-04-22 | 2014-03-26 | 江西中烟工业有限责任公司 | Device for detecting releasing amount of hydrogen cyanide in cigarette smoke |
| JP6117009B2 (en) * | 2013-06-12 | 2017-04-19 | 鹿島建設株式会社 | Cyan density measurement method |
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