IS 15694: Paotassium iodate, food grade

2006·1.3 MB·English

by  Bureau of Indian Standards

इंटरनेट मानक
Disclosure to Promote the Right To Information
Whereas the Parliament of India has set out to provide a practical regime of right to
information for citizens to secure access to information under the control of public authorities,
in order to promote transparency and accountability in the working of every public authority,
and whereas the attached publication of the Bureau of Indian Standards is of particular interest
to the public, particularly disadvantaged communities and those engaged in the pursuit of
education and knowledge, the attached public safety standard is made available to promote the
timely dissemination of this information in an accurate manner to the public.
“जान1 का अ+धकार, जी1 का अ+धकार” “प0रा1 को छोड न’ 5 तरफ”
Mazdoor Kisan Shakti Sangathan Jawaharlal Nehru
“The Right to Information, The Right to Live” “Step Out From the Old to the New”
IS 15694 (2006): Paotassium iodate, food grade [FAD 8: Food
Additives]
“!ान $ एक न’ भारत का +नम-ण”
Satyanarayan Gangaram Pitroda
““IInnvveenntt aa NNeeww IInnddiiaa UUssiinngg KKnnoowwlleeddggee””
“!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता हहहहै””ै”
Bhartṛhari—Nītiśatakam
“Knowledge is such a treasure which cannot be stolen”

IS 15694:2006

IndianStandard
POTASSIUM IODATE, FOOD GWDE —
SPECIFICATION
lCS 67.220.20

0 BIS 2006
BUREAU OF INDIAN STANDARDS
,
MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG
I
NEW DELHI 110002

:)ctober 2006 Price Group 3
-.
.—. - ——-. .--— —
Food Additives Sectional Committee, FAD 8
FOREWORD
This Indian Standard was adopted by the Bureau of Indian Standards, afier the drafi finalized by the Food
Additives Sectional Committee had been approved bythe Food and Agriculture Division Council.
Potassium iodate iswidely used for ionization of edible common salt. This standard has been prepared to cover
the purity and identification of potassium iodate. This is extremely important, for it is extremely difficult to
detect the impurity once ithas been added to processed foods.
The requirement of foodgrade potassium iodate as given inthis standard was earlier a part-ofIS 13057:1991
‘Specification for potassium iodate’, wherein 3grades— analytical, food andtechnical were specified. Through
an amendment to 1S13057 in 2003, the foodgrade has been deleted from IS 13057 and, therefore, a separate
standard has been formulated to cover the foodgrade potassium iodate.
Inthe preparation ofthis standard, due consideration hasbeen given tothe provisions ofthe Prevention of Food
Atiulteration Act, 1954 and Rules framed thereunder. However, this standard is subject to restrictions imposed
under this Act, wherever applicable.
‘Forthe purpose of deciding whether aparticular requirement of this standard iscomplied with, the final value,
observed or calculated, expressing the result of a test or analysis; shall be rounded off in accordance
with IS 2 : 1960 ‘Rules for rounding off numerical values (revised’. The number of significant places retained
inthe rounded off value should bethe same asthat of the specified value inthis standard.
.—— ——.. ___ _
1S15694:2006
IndianStandard
POTASSIUM IODATE, FOOD GMDE —
SPECIFICATION
1 SCOPE 4 4 PACKING, STORAGE AND MARKING
This standard prescribes the requirements and the 4.1 Packing
methods of sampling and test for potassium iodate,
The material shall be packed inwell-filled containers
food grade.
withminimumaccesstomoisture. Thecontainers shall
be such as to preclude contamination of the contents
2 REFERENCES
with metals or other impurities.
The following standards contain provisions which,
4.2 Storage
through reference inthis text, constitute provisions of
this standard. At the time of publication, the editions The material shall bestored inacool, dry place so as
indicated were valid. All standards are subject to to avoid excessive exposure to heat.
revision and parties to agreements based on this
4.3 Marking
standard are encouraged to investigate the possibiIity
of applying the most recent editions of the standards 4.3.1 Each container shall be legibly and indelibly
indicated below: marked with the following information:
IS No. Title a) Name of the product including the words
I070:1992 Reagent gradewater (third revision) ‘Food Grade’;
1699:1995 Methods of sampling and test for b) Name and address ofthe manufacturer;
food colours (second revision) c) Source of manufacture;
4905:1968 Methods for random sampling d) Minimum net contents;
5741:1970 Method for determination ofpH e) Date of manufacture;
o Batch or code number;
3 REQUIREMENTS
g) The words ‘Best before .......’ (month and
3.1 Description year to be indicated); and
h) Any other requirements as specified under
The material shall be inthe form of white crystalline
the Standards of Weights and Measllres
powder, free from impurities.
(PachagedCommodities) Rules, 1977 andthe

3.2 Thematerialshallalsoconformtotherequirements Prevention of Food Adulteration Act, 1954
given inTable 1. and Rules framed thereunder.
‘Table 1 Requirements for Potassium -Iodate
(Clazlse 3.2)
SI Characteristic Requirement Method ofTest, Ref tu
No. / A 3
Annex ofthis Clause No.
Standard 1S1699
(1) (2) (3) (4) (5)
i) Potassium iodate (asK1OI), percent bymass,Min 99.8 A-2 —
ii) Matter insoluble inwater, percent bymass,Jfm 0.10 A-3 —
iii) Bromate, bromide, chlorate andchloride (asCl), percent 0.01 A-4 —
bymass, A[ax
iv) Iodide (as1),percent bymass,Mu 0.002 A-5 —
v) Sulphate (asS04), percent bymass,A4a 0.02 A-6 —
vi) hss ondrying, percent bymass, Max 0.1 A-8 —
vii) Iron, nl~kg, Ma 3 A-7 —
viii) Wavy metals (as Pb), mfig, Ma 10 — 16
ix) Arsenic, nlg/kg, Max 3 — 15
x) pH (5 percent solution) Neutral A-9 —
1S15694:2006
4.3.2 BISCertification Marking 5 SAMPLING
The product may also be marked with the Standard Representative samples ofthe material shall bedrawn
Mark. andthecriteria forconformity tothisstandard shall be
established according to the method prescribed in
4.3.2.1 Theweofthe Standard Mark isgovernedby
Annex B.
the provisions ofthe Bureau of Indian Standards ACI,
1986andthe Rules and Regulations madethereunder. 6 QUALITY OF REAGENTS
The detaiIsof conditions under which the Iicence for Unless specified otherwise, pure chemicals and
the use of the Standard Mark may be granted to di~tilledwater(seeIS 1070)shallbeemployed intests.
manufacturers or producers maybeobtained from the
NOTE — ‘Pure chemicals’ shall mean chemicals that donot
Bureau of 1ndian Standards.
contain impurities which affect the results of analysis.
ANNEX A
(Clause 3.2, Tuble 1)
METHOD OF TEST FOR POTASSIUM IODATE
A-1 PREPARATION OF SAMPLE A-2.3 Calculation
A-1.1 Sample for determination of potassium iodate Potassium iodate (as KIOJ),
(q-~)
content shall be the residual material obtained at the percent bymass = 3.567 ~
end of the test for losson drying.
where
A-1.2 Sample for Other Tests
VI = volume in ml of standard sodium
Crush 100g of the sample so that it passes through
thiosulphate solution used in titrating the
1.00 mm IS Sieve, and keep it in a clean glass-
sample,
stoppered weighing bottle in a desiccator for sub-
sequent tests. ~z = volume in ml of standard sodium
thiosulphate solution used in titrating the
A-2 DETERMINATION OFPO T ASSIUM IODATE blank, and

A-2.1 Reagents M = mass ing ofthe sample taken for the test.
A-2.1.1 Potassium iodide A-3 DETERMINATION OF MATTER
.INSOLUBLE IN WATER
A-2.1.2 Hydrochloric Acid — Approximately 5N.
A-3.1 Procedure
A-2.1.3 Siandard Sodium Thiosulphate Solution —
0.1 N. Dissolve20 gofthesample(seeA-1.2) inabout400 ml
of warm water. Cool the solution and set it aside for
A-2.1.4 Starch Indicator Solution — Mix 0.5 g of
1h. Filter through a weighed sintered glass crucible
soluble starch with 5 ml of cold water. Add this
mixture, with stirring, to-95 ml of boiling water and (GNo. 4). Wash the residue with water and dry to
heat ina boiling water bath for 5min. constant mass at 105°C.
A-2.2 Procedure A-3.2 Ca~ulation
Dissolve 1.5gofthedried material (at 130°C)inwater Matter insoluble inwater, ~ ~~O.
anddilute to 500 ml.To 50 mlofthis solution add3g percent bymass = 1
Mz
of potassium iodide and 10-nllof dilute hydrochloric
acidandtitrate the liberated iodinewith0.1Nstandard where
sodiutn thiosulphate solution, usingstarchasindicator.
Ml= mass ingof the residue, and
Perform a blank determination and make necessary
correction, ifany. M2= mass ing ofthe sample taken for the test.

2
IS 15694:2006
A-4 TEST FOR BROMATE, BROMIDE, A-6 TEST FOR SULPHATE
CHLORATE AND CHLORIDE
A-6.1 Method A(Turbidimetric Method)
A-4.1 Reagents
A-6. 1.1 Reagents
.
A-4.1.1 Sulphur Dioxide
A-6. 1.1.1 Industrial methylated spirit (absolute,
A-4.1.2 Dilute Ammonia Solution — Approximately 74 OP)
5N. Add 280 ml of strong ammonia solution (AR or
A-6. 1.1.2 Industrial methylated spirit PO percent)
GR grade, rd 0.88) to sufficient water to-makeupthe
— Dilute 20 ml of absolute industrial methylated
volume to 1000 ml.
spirit with water to produce a final volume of
A-4. 1.3 Silver Nitrate Solution — 0.1 N. Dissolve 100 ml.
16.087gofsilvernitrate(ARorGR grade) insuticient
A-6.1.1.3 Barium chloride solution — Approximately
water to make upthe volume to 100ml.
1N. Dilute 430 ml of hydrochloric acid (AR or GR
A-4.1.4 Dilute Nitric Acid— Approximately 5N.Add grade, rd 1.18) with sufficient water to make up the
320 ml of nitric acid (AR or GR grade, rd 1.42) to volume to 1000 ml.
sufficient water and make upthe volume to 1000 ml.
A-6.1. 1.4 Standard sulphate solution — Dilute
A-4.1..5 Standard Chloride Solution — Dissolve 20.8 ml of 0.1N sulphuric acid with sufficient water
O.i64 gof sodium chloride (NaCl) inwater anddilute to make up the volume to 1 000 ml. This solution
to 1 000 ml. One mi[lilitre of this solution contains contains 0.1 mgof SO~per ml.
0.1 mg of chloride (as Cl).
A-6. 1.2 Procedure
A-4.2 Procedure
A-6. 1.2.1 Dissolve 1gofthesamplein40ml ofwater,
A-4.2.1 Dissolve 0.5 gofthesample-in50mlofwater add 0.6 gofhydroxy ammonium chloride and boil till
and pass sulphur dioxide into the solution until the the liberated iodine isexpelled. Cool, dilute to 40 ml
precipitate ofiodineredissolves.Evaporate thesolution withwater, add 10mlofdilute hydrochloric acid. Mix
to about 2 ml, cool, add 6 ml of dilute ammonia the resulting solution after adding 1ml of barium
solution, transfer to astoppered testtube anddilute to chloride solution, and allow to stand for 1h. Any
15mlwith water. Add 15mlofsilver nitrate solution, turbidity producedshallnotbegreaterthanthestandard
shake well andfilter. To 15mlof filtrate, add30 mlof turbidity produced as inA-6.1.2.2.
water and 5ml of dilute nitric acid. Any opalescence
A-6.1.2.2 Standard turbidity
produced shall not be greater than the standard
opalescence produced as inA-4,2.2. Take 2 mlof standard sulphate solution. Add 37 mlof
water, 10ml of absolute industrial methylated spirit,
A-4.2.2 Standard Opalescence
1mlofdilute hydrochloric acid and mix. Add 1ml of
To 50 ml of water, add 0.5 ml of standard chloride barium chloride solution, mix immediately and allow
solution, 1ml of dilute nitric acid and 1ml of silver to stand for 1h.
nitrate solution, mixing afier each addition. Use as
comparison standard afier 5min. A-6.2 Method B (Gravimetric Method)
A-6.2. 1 -Reagents
A-5 TEST FOR 10D1DE
A-6.2. 1.1 Dilute hydrochloric acid— Approximately
A-5.1 Reagents
4N.
A.5. 1.1 Dilute Sulphuric Acid
A-6.2. 1.2 Barium chloride — Approximately
A-5. 1.2 Starch Indicator Solution — Triturate 1gof 10percent.
arrowroot starch with 10ml of cold water and pour
slowly, with constant stirring, into 200 ml of boiling A-6.2.2 Procedure
water. Boil the mixture until athin translucent fluid is Dissolve 1gofthesample in40 mlofwater, add0.6 g
obtained. Allow to settle and use only the clear,
of hydroxy ammonium chloride and boil till the
supernatant liquid. Prepare this solution fresh.
liberated iodine isexpelled. Cool anddilute to400 ml
with water.Add one drop ofmethyl orange and about
A-5.2 Procedure
10mlofdilute hydrochloric acid till itbecomes pink
Dissolve I gofthe material in 10mlofwater andadd and then boil. To the boiling solution add barium
1ml of dilute sulphuric acid and 1 drop of starch chloride solution drop bydrop sothat the addition is
solution. No blue colour shall be formed. in slight excess and continue boiling for 4 min .to

3
IS 15694:2006
obtain agranular precipitate. Allow ittostand for4 h dioxide through the solution until the precipitate of
and filter through a weighed sintered glass crucible iodine redissolves. Evaporate the solution to dryness
(G No.4). Wash the precipitate till it is free from on a hot pIate, mix the residue with 10ml of dilute
chloride and dry to constant mass at 105 to 11O°C. hydrochloric acidandevaporate to dryness onasteam
Alternatively, filter through Whatman filter paper No. bath. Dissolve the residue bywarming with a mixture
42 and wash till it is free from chloride. Ignite and of3mlofdilute hydrochloric acid and27 mlofwater.
weigh as barium suiphate. Retain 20 ml for the heavy metals test and to 10ml
apply the irontest asgiven inA-7.3.1.
A-6.2.3 Calculation
A-7,3. 1 Take 10ml of solution in a 50 ml Nessler
Sulphate (as SOa), 41.13M, cylinder obtained in A-7.3, add 1drop of potassium
percent by mass= ~ permanganate solution and mix. Add 5 ml of
2 ammoniumthiocyanate solutionand 10mlofamixture
of equal volumes of amyl alcohol and amyl acetate.
where
Shakevigorously andallowtoseparate.Anyredcolour
Ml= mass ingofthe barium sulphate precipitate, produced inthe upper layer shall not be deeper than
and that produced in the upper layer of the standard as
inA-7,3.2.
M2=mass ingof the sample taken for the test.
A-7.3.2 To I mlofstandard iron solution ina50 ml
A-7 TEST FOR IRON
Nessler cylinder, add 1ml of dilute hydrochloric
A-7.1 Apparatus acid and dilute with water to the same volume as
the acidified solution ofthe test sample. Add Idrop
A-7. 1.1 Nessler Cylinder — 50 ml capacity.
of potassium permanganate solution and mix. Add
A-7.2 Reagents 5 mlof amixture of equal volumes ofamyl alcohol
and amyl acetate. Shake vigorously and allow to
A-7.2.1 Dilute Sulphuric Acid— Approximately 5N.
separate.
Pour 136ml of sulphuric acid (AR grade, 36 N) in
sufficient quantity of water, mix and allow to cool. A-8 DETERM1NATION OF LOSS OF MASS ON
Make the volume to 1000 ml. DRYING AT 130°C
A-7.2.2 Dilute Hydrochloric Acid — Approximately A-8.1 Apparatus
5N. Dilute 430 mlofhydrochloric acid(ARgrade, rd
A-8.1. 1 Weighing Bottle — Approximately 100 ml
1.18)with sufficient water to make up the volume to
capacity, 75 mm in diameter, with ground glass
1000 ml.
stopper.

A-7.23 Polassium Permanganat e Solution — O.i N.
A-8.1.2 Electric Oven — Capakle of maintaining a

A-7.2.4 Ammonium Thiocyanate Solution — temperature of 130*2°C.
Approximately 7.5 N. Dissolve 570 g of ammonium
thiocyanate (AR grade) in suficient water and make A-8.2 Procedure
up the volume to 1000 ml. Weigh5gofthematerial tothenearest 0.1 mg.Spread
thin layersofthe material intheweighing bottle which
A-7.2.5 AiuY/ Acetate — AR or GRgrade.
shall be previously dried for 30 min in the oven
A-7.2.6 Amyl Alcohol — AR or GR grade. controlled at a temperature of 130°C, cooled in a
desiccator and weighed. Place the weighing bottle in
A-7.2.7 Standard Iron Solution — Dissolve0.0702 g theovenwithitsground glassstopper placedslantwise.
of ferrous ammonium sulphate .[FeSOd.(NHt)z SOd.
Gradually heat the oven from the starting temperature
6HZO] inwater, andadd 10mlofdilute sulphuric acid
(which should not exceed 100°C) to 130tiJC and
(10 percent v/v). Dilute to exactly 100 ml in a
maintainthistemperature for 1h.Removetheweighing
volumetric flask. Take 25 ml of this solution into a
bottle, place it inadesiccator and cool. Afier cooling
250 ml volumetric flask and dilute to the mark with
-toroomtemperature, weigh itagainwiththestopper in
water. One millilitre of this solution contains 0.01 mg
position.
of iron (as Fe).
A-8.3 Calculation
A-7.3 Procedure
Lossofmassondrying
Dissolve 3g of the sample in a mixture of 30 ml of (M, -M2)XI00
at 130°C,percent by mass=
waterand5mlofdilutesulphuric acidandpasssulphur M

4
1S15694:2006
where A-9 DETERM1NATION OF PH OF AQUEOUS
SOLUTION
M, = massing ofthematerial andweighingbottle
before heating, Dissolve 5.0 g of the material in 100ml of freshly
M2= massing ofthematerial andweighingbottle boiled and cooled water (the water shall be protected
after heating, and withsoda limetube while cooling). Determine thepH
M = mass ing ofthe material taken for thetest. ofthesolution usingasuitablepH meter (see1S5741).
ANNEX B
(C/ause 5)
SAMPLING OF POTASSIbM IODATE
,
B-1 GENERAL REQUIREMENTS OF Table 2 Number of Containers to be
SAMPLING Selected for Sampling
(Clause B-2.2)
B-1.0 In drawing samples, the following precautions
and directions shall be observed. Lot Size NumberofContainerstobeSelected
N n
B-1.1 Precautions shallbetakentoprotectthesamples, (1) (2)
the material being sampled, the sampling instrument
and the containers for samples from adventitious 4-50 3
51-100 4
contamination.
101-150 5
B-1.2 The samples shall be placed in suitable clean 151-300 1
and dry containers. 30I andabove 10
NOrE — When the size of the lot is3 or less, the number of
B-1.3 The sample containers shallbeofsuchsizethat containers tobe selected and the criterion or judging the
they are almost completely filled by sample. conformity of the lottothespecification shall beasagreed to
between the purchaser and thesupplier.

B-1.4 Each sample containers sh all be sealed airtight
after filling and marked with full de t ails of sampling B-2.3 These containers shall be selected at random
and the date of sampling. from the lot. For random selection procedure,
guidelines can behad from IS 4905. In case 1S4905
B-2 SCA”LEOF SAMPLING is not available, the following procedure shall be
adopted:
B-2.1 Lot
Arrange allthecontainers inthe lotinasystematic
All the containers in a single consignment of the
manner and starting from any one, count them
material drawnfromasinglebatchofmanufactureshall
1,2, 3,..., etc, up to r and so on, where r isthe
constitute alot. Ifaconsignment isdeclared orknown
integral part of N/n. Every rth container thus
to consist of different batches of manufacture, the
counted shallbetaken out.
containers belongingtothesamebatchshallbegrouped
together andeachsuchgroupshallconstitute aseparate B-3 PREPARATION OF TEST SAMPLES AND
lot. REFEREE SAMPLE
B-2.2 Samples shallbetested fromeachlotseparately B-3.1 For drawing samples, an auger shall be used.
Introducetheauger indifferent parts ofeach container
for ascertaining conformity of the material to the
todrawanappropriate quantityofthesamplefromeach
requirements of this specification. The number of
container.
containers to be selected from a lot (n) shall depend
on the size of the lot (~ and shall be in accordance B-3.2 Out of portions collected from all the selected
with Table 2. containers, an equal quantity of the material shall be
5