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.

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“Step Out From the Old to the New”

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“The Right to Information, The Right to Live”

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“Knowledge is such a treasure which cannot be stolen”

“Invent a New India Using Knowledge”

है”ह”ह

IS 14950 (2001): Fish - Dried and Dry-Salted [FAD 12: Fishand Fisheries Products]

Is 14950:2001

( Superseding IS 2345:1985, IS 2883:1985, IS 2884:1979,

IS 3850:1973, IS 3851:1966, IS 3852:1985, IS 3853:1985,

IS 4302:1985, IS 5198:1985, IS 5199:1985, IS 5471:1969,

IS 5472:1985, IS 5736:1985 and IS 8836: 1985)

Wwh Ji/d*

Indian Standard

FISH — DRIED AND DRY-SALTED —SPECIFICATION

July 2001

ICS 67.120.30

0 BIS 2001

BUREAU OF INDIAN STANDARDSMANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG

NEW DELHI 110002

●

Price Group 5

Fish and Fisheries Products Sectional Committee, FAD 12

FOREWORD

This Indian Standard was adopted by the Bureau of Indian Standards, afler the drafi finalized by the Fish andFisheries Products Sectional Committee had been approved by the Food and Agriculture Division Council.

A variety of Indian fishes are sold internally and also exported in dried form and dry-salted form. Earlier, therequirements of individual fish were covered under separate standards namely, IS 2345 : 1985 ‘Dried prawns/shrimps ( second revision )’, IS 2883 : 1985 ‘Dried white baits ( STOLEPHORUS sp ) ( second revision )’,IS 2884 : 1979 ‘Dried and laminated Bombay Duck (first revision )’, IS 3850: 1973 ‘Dry-salted thread fin( DARA ) and dry-salted jewfish ( GHOL ) (first revision )’, IS 3851:1966 ‘Dry-salted catfish’, IS 3852:1985‘Dry-salted leather jackets ( CHORINEMUS sp ) (first revision )’, IS 3853: 1985 ‘Dry-salted horse mackerels( CARANX sp ) (first revision )’, IS 4302:1985 ‘Dry-salted mackerel (first revision )’, IS 5198:1985 ‘Dry-salted seer fish (first revision )’, IS 5199:1985 ‘Dry-salted shark (first revision )’, IS 5471 : 1969 ‘Dried sharkfins’, IS 5472:1985 ‘Fish maws (first revision )’, IS 5736:1985 ‘Dry-salted SURAI ( TUNA) (first revision)’and IS 8836: 1985 ‘Dry-salted DHONIA (first revision )’. While reviewing these, it was decided to amalgamatethese in one comprehensive standard to make it user friendly. Consequently this new standard would supersedeabove mentioned standards. Besides amalgamating the standards, requirements for microbiological and heavymetal limits, have also been added.

In the preparation of this standard, due consideration has been given to the provisions of the Prevention of FoodAdulteration Act, 1954 and Standards of Weights & Measure (Packaged Commodities) Ru[es, 1977. However,this standard is subject to the restrictions imposed under these, wherever applicable.

PFor the purpose of deciding whether a particular requirement of this standard is complied with the final value,observed or calculated, expressing the result of a test or analysis, shall be rounded off in accordance withIS 2: 1960 ‘Rules for rounding of numerical values ( revised )’. The number of significant places retained inthe rounded off value, should be the same as that of the specified value in this standard.

Is 14950:2001

Indian Standard

FISH — DRIED AND DRY-SALTED —SPECIFICATION

1 SCOPE

This standard prescribes the requirements and themethods of sampling and test for various types of driedand dry-salted fish.

2 REFERENCES

The following Indian Standards listed contain provisionswhich through reference in this text, constitute provisionof this standard. At the time of publication, the editionsindicatedwere valid. All standards are subject to revisionand parties to agreements based on this standard areencouraged to investigate the possibility of applyingthe most recent editions of the standards indicatedbelow

1SNo.

594:1981

2237:1997

4303

(Part 1): 1975

(Part2) :1975

11427:2001

Title

Common salt for fish curing (secondrevision )

Prawn — Frozen — Specification( third revision)

Code of hygienic condition for fishindustry:

Pre-processing stage ( j7rstrevision )

Canning stage (jlrst revision)

Fish and fishery products —Sampling (first revision )

3 VARIETY OF FISH

For the purpose of this standard, particular variety ofa fish or shell fish given in Annex A shall include allthe important commercial species of that fish or shellfish.

4 GRADES

Necessary grades designation for various types of fishmay be assigned based on size and mass of a singlepiece of fish as given in Annex B. A tolerance of 10percent by mass of the net mass of the next higher orlower grade or both grades put together in a pack shallbe included.

5 DESCRIPTION

5.1 The product, its skin and flesh shall havecharacteristics colour. The meat and stomach portionshould be firm.

1

5.2 The material shall be tlee from visible fhngal, insector mite infestation.

6 REQUIREMENTS

6.1 The material shall be prepared and processed asgiven in Annex C under hygienic conditions[seeIS4303 (Parts land2)].

6.2 The material shall be free from artificial colouringmatter and firming agents except common salt. Foodadditives for fish and fisheries products permitted underPFA Rules maybe used.

6.3 The material shallmeet the microbiological and heavymetal requirements as given in Table 1.

Table 1 Microbiological and Heavy MetalRequirements

( Clause 6.3)

SI Characteristic Requirement Method of Test,No.

(1) (2)

i) Total plate count,Mizxlg

ii) E.coli, Maxlg

iii) Coagulasepositive,Staphylococci, Maxlg

iv) Salmonella, per 25 g

v) Heavy metals:

a) Mercury,mgkg, Max

b) Zinc, mgkg, Max

c) Copper, mgkg, Max

d) Arsenic,mgkg, Max

e) Lead,mgilcg,Max

t) Tin, mg/kg,Max

1) For product packedin tin plate

2) For product packedin other packing

containers

(3)

100000

20

100

Absent

0.5

50.0

10.0

1.0

1.0

50.0

250.00

Ref to Annex of1S2237

(4)

B

c

E

F

L-3

L-4

L-4

L-5

L-6

L-7

6.4 Dry fish and dry-salted fish shall also conform tothe requirements given in Table 2 and Table 3respectively.

.

1s 14950:2001

7 PACKING AND MARKING

7.1 Packing

The material shall be packed in a suitable package/container as agreed between the purchaser and theprocessor. Intheabsence ofanysuch agreement thematerial shall be packed in packages which are leak-proof, impermeable to oxygen and moisture and preventdeterioration during transportation and storage. Incase polyester/polythene laminates are used, only foodgrade plastic materials shall be used.

7.2 Marking

7.2.1 Each container shall be marked or labelled withthe following particulars:

a)

b)

c)

d)

e)

Name of the material with indication of driedor dry-salted;

Name and address of the processor;

Batch number or code number;

Grade;

Net mass;

o

g)

h)

Date of packing;

The words ‘Best before ...... (month and year)’to be indicated; and

Any other requirements as specified underthe Standards of Weights and Measures(Packaged Commodities) Rules, 19771Prevention ofFoodAdulteration Rules, 1955.

7.2.2 BIS Certification Marking

The product may also be marked with the StandardMark.

7.2.2.1 The use of the Standard Mark is governed bythe provisions of the Bureau of Indian Standards Act,1986 and the Rules and Regulations made thereunder.The details of conditions under which the Iicence forthe use of the Standard Mark may be granted tomanufacturers or producers maybe obtained from theBureau of Indian Standards.

8 SAMPLING

8.1 The method of drawing representative samples ofthe material, both fresh and frozen for test and the criteriafor conformity shall be according to the methodprescribed in IS 11427.

. . .

Table 2 lkqui~ments for Dry/Salted Fish and Fish Products

( Clause 6.4)

S1 Characteristics Dry-SaltedNo. Mackerel

(1) (2) (3)

i) Moisture, percent 30.0by mass, Max

ii) Sodium chloride 25.0-30.0(on moisture freebasis> percentby mass

iii) Acid insoluble ash 1.5(on moisture freebasis), percent by

mass, Max

Dry-SaltedSeer Fish

(4)

35.0

25.0 -30.0

1.5

Dry-SaltedLeatherJacket

(5)

35.0

25.0 -30.0

1.5

Dry-SaltedSurai(lima)

(6)

35.0

20.0-25.0

1.5

Dry-Salted Dry-Salted Dry-SaltedShark Cat Fish Threadfin

(Dara)

(7) (8) (9)

35.0 35.0 40.0

25.0-30.0 25.0 25.0Min Min

1.5 1.5 1.5

Dry-Salted Dry-Salted Dry- Method of Test,Jew Fish Horse Salted Ref to Annex

(Ghol) Mackerel Dhoma

(lo) (11) (12) (13)

40.0 35.0 35.0 D

25.0 25.0-30.0 10.0 -15.0 EMin

1.5 1.5 2.0 F

w

Table 3 Requirement of Dried Fish( Clause 6.4)

S1 CharacteristicsNo.

(1) (2)

i) Moisture, percent bymass, Max

ii) Sodium chloride( on moisture freebasis ), percentby mass, Max

iii) Acid insoluble ash(on moisture freebasis), percent by

mass, Max

Material— .——— ——. - .-— — ——. .—

Dried Laminated Dried Dried Dried DriedBombay Duck Bombay Duck White Baits Prawns Shark Fins Fish Maws

(3) (4) (5) (6) (7) (8)

15.0 15.0 15.0 20.0 10.0 8.0

7.5 6.0 2.5 5.0 — —

1.0 1.0 1.5 1.0 1.5 1.5

Method of Test,Ref to Annex

(9)

D

E

1 i

IS 14950:2001

.-L!_

4

VARIETY

1. Mackerel

2. Seer Fish

3. Leather Jackets

4. Surai (Tuna)

5. Shark

6. Cat Fish

7. Threadfin (Dara)

8. Jew Fish (Ghol)

9. Horse Mackerel

ANNEX A( Clause 3 )

VARIETY OF FISH WITH SPECIES

SPECIES

Rastrelliger SP.

a) Scomberomorus guttatusb) S. commersonc) S. lineolatusd) S. kuhillie) S. interruptus

a) Chlorinemus Iysanb) C. talac) c. told) S. sanctipetri

Thunnus sp.

a) Pristis sp.b] Galeocerdo sp.c) Sphyrna sp.d) Carcharinus sp.

a) Arius sp.b) Batrachocephalus sp.c) Osteogineosus sp.d) p[otosus Sp.

a) Polynemus sp.b) Polydactylus indicus

Pseudosciaenna diacanthus

a) Alectis sp.b) A[epes sp.c) Atropus sp.d) Carangoides sp.e) Caranx sp.f) Citula sp.

VARIETY SPECIES

Horse Mackerel g) Decapterus sp.( Contd ) h) EIagatis sp.

j) Gnathanoidon sp.k) Megalaspis sp.m) Naucrates sp.n) Scomberoides sp.p) Selar sp.q) Selaroides sp.r) Seriola sp.s) Trachinotus sp.t) Ura. spis sp.

10. Dhoma a) Johnieops sp.(Croakers or b) Johnius sp.Jew Fish) c) Nibea sp.

d] Otolithus sp.e) Protonibea sp.O Sciaena sp.

11. Bombay Duck Harpodon nehereus

12. White Baits Stolephorus sp.

13. Prawns a)b)c)

14. Fish Mawa) Eelb) Jew Fishc) Threadfind) Giant Croakere) Cat Fisht) Bektig) Lizard Fish

Penaeus sp.Metapenaeus sp.Parapenaeopsis sp.

Miraemesox talabonoidesPseudosciaena spPolynemus indicusOtolithoides brunneusArius sp, Tachysures spLates sp, Psmoperca spSaurida sp

4

Is 14950:2001

ANNEX B( Clause 4 )

GRADES

B-1 DRY-SALTED MACKEREL

The material shall be of the following two grades:

Grade Mass, g

Large Above 50Standard 50 and below

B-2 DRY-SALTED SEER FISH

The material shall be of the following two grades:

Grade Length, cm’)

With Head Without Head

Small up to 45 up to 37.5Large Above 45 Above 37.5

NOTE — In the case of ‘large’ grade it may be eitherdried whole or may be cut into convenient piecestransversely before curing.

B-3 DRY-SALTED LEATHER JACKETS

The material shall be of the following two grades:

Grade Mass, g

With Head Without Head

Large 400 and above Above 350Standard Below 400 Below 350

B-4 DRY-SALTED SURAI ( TUNA )

The material shall be of the following two grades:

Grade Mass, g

Small upto1000Large Above 1000

B-5 DRY-SALTED SHARK

The material shall be of three grades:

Grade Mass, g

Large Above 3000Medium 3000-1000small Below 1000

B-6 DRY-SALTED CAT FISH

The material shall be of two grades:

Grade Mass, g

With Head Without Head

Large 500 and above 400 andabove

Standard Below 500 Below 400

1)Total lengthin centimetres of a single Salt cured seer

fish.

B-7 DRY-SALTED THREADFIN (DARA)

The material shall be of two grades:

Grade Mass, kg

With Head Without Head

Extra large Above 4 Above 3.5

Large 3t04 2t03.5

B-8 DRY-SALTED GHOL

The material shall be of two grades:

Grade Mass, kg

With Head Without Head

Extra large Above 3.5 Above 3

Large 2.5 to 3.5 2t03

B-9 DRY-SALTED HORSE MACKEREL

The material shall be of the following two grades:

Grade Mass, kg

With Head Without Head

Large 400 and above 350 andabove

Standard Below 400 Below 350

B-10 DRY-SALTED DHOMA ( CROAKERS OR,JEW FISH)

The material shall be of the following three grades:

Grade Mass, g

Large Above 150

Medium looto 150

small Below 100

B-11 DRIED BOMBAY DUCK

The material shall be of three grades basedand mass:

on size

Grade Size, cm’) Mass, kg2J

Large Above 20 Above 10

Medium 15t020 7.5 to 10

Small Below 15 Below 7.5

1) Length in Mntimetres measured from the tiP of the

snout to the base of the caudal fin in the case of thedried fish.

3 Mus of 1000 individual fish in kilograms.

.

5

IS 14950:2001

Grade Size, cm’ )

c 30 and below 40

D 40 and above

B-16 DRIED FISH MAWS

The material shall be of the following three grades:

Grade 1 — Clear to slightly discolored.

Grade 2 — Moderately mottled.

Grade 3 — Extensively discolored.

B -16.1 The material shall be of the size grades as givenin Table 4.

Table 4 Size Grades

( Clause 16.1)

B-12 LAMINATED BOMBAY DUCK

The material shall be of two grades based on size andmass:

Grade Size, cm’) Mass, kg2J

Large 15 and above 500 andabove

Small Less than 15 Less than 500

B-13 DRIED WHITE BAITS

The material shall be of two grades based on count:

Grade Count3)

Large Below 200

Small 200 and above

B-14 DRIED PRAWNSS1 No.

(1)

i)

Name of Species

(2)

Eel

Grades Count/kg

(4)

15 and below

16 to 30

31 to 45

Above 45

Broken

12 and below

13 to 25

Above 25

Broken

7 and below

8 to 15

16 and above

Broken

7 and below

8 to 15

16 and above

Broken

40 and below

41 to 100101 and above

Broken

12 and below

13 and above

Broken

15 and below

16 and above

Broken

The material shall be of the following four gradesdepending upon count:

(3)

a)

b)

c)

d)

e)

Grade Cound)

Large Below 50

Medium 50 to 250

small 251 to 500

Tiny Above 500 ii) Jew a)

b)

c)

d)

B-15 DRIED SHARK FINS

The material shall be of the following two types:

a) White fins, and iii) a)b)

c)

d)

b) Black fins.. .

Depending upon the size of the fins the material shallbe of the following grades:

ivj Giant croaker a)

b)

c)

d)

a) Dorsal, Ventral and Pectoral fins:

Grade Size, ems)

A Below 10

B 10 and below 20

c 20 and below 30

D 30 and above

v) Cat fish a)b)

c)

d)b) Caudal ( tail ) fins:

Bektivi)

vii)

a)b)

c)

Grade Size, cm5)

A Below 20

B 20 and below 30

l) Lengthin centimetres of the laminatedpiece.

z) Massof 100pieces in grams.

Lizard fish a)b)

c)

3, Count= Number of white baits per I 000 g.

4, Count = Number of prawns per 1000 g.

1) Length of a single dried shark fin in centimetres whenmeasured from the tip to upper or anterior corner.

-$)Length of a single dried shark fin in centimetres when

measured from the tip to upper or anterior corner.

Is 14950:2001

ANNEX C

( Clause 6.1 )

PREPARATION

C-1 DRY-SALTED FISH

In the preparation of dry-salted fish ( mackerel, leatherjacket, seer fish, surai, shark, cat fish, threadfin, jewfish, horse mackerel and dhoma ) the fresh fish is splitopen by a cut !lom dorsal side along the vertebml cohnnnand the entrails and gills are removed. The knife ispassed deep along the.vertebral column and the fishis flattened out. Scores are made pn the thick fleshyparts by passing the knife lengthwise. After washingthe fish, salt shall be smeared in proportion of not lessthan 1:4 by mass on the cut surface of the fish andthe fish is kept under cure for not less than 24 h. Saltused for curing shall conform to IS 594. The saltedfish is washed slightly to remove excess of undissolvedsalt and dirt. The fish is dried in sun spread over dryingracks for a period of 10 to 18 h over two to three days.During drying, the fish is turned upside downoccasionally to facilitate quicker and even drying. Thefish while drying shall be protected againstcontamination from dirt, sand, flies and insects. In thecase of large size fish, it maybe cut longitudinally intopieces of suitable size.

C-2 DRIED BOMBAY DUCK

In the preparation of dried Bombay duck, the freshfish as soon as it is landed is washed with clean waterto remove all adhering impurities and hung in pairson ropes between vertical poles, the jaws being usedfor locking in pairs. The tish is dried in the sun. Itmay also be dried in artificial driers.

C-3 LAMINATED BOMBAY DUCK

[n the preparation of laminated Bombay duck, the freshtish is thoroughly washed in clean water. The gutsare removed and then washed well again. The guttedtlsh are suspended from a scaffold for surface dryingfor about 2h. At this stage, remove the head, tail andtins using a sharp knife or scissors and splitlongitudinally along the belly portion. Bones can beremoved if required. Dip the fish thus laminated insufficient quantity of 1 percent brine (prepared fromrefined salt) for 20 min. Drain the fish and spread ondrying racks to a moisture level of 16-17percent. Flattenthe product by means of a roller press. Trim the sidesto get pieces of uniform size. Dry the product againfor 1-2 h so that the final moisture content is about 15percent. It is always advantageous to use a tunneldrier for drying the product to improve the quality ofthe finished product.

C-4 DRIED WHITE BAITS

In the preparation of dried white baits, the fish shall

be cleaned thoroughly with potable water and driedeither in the sun on clean raised platforms or dryingracks or in artificial driers.

C-5 DRIED PRAWNS

In the preparation of dried prawns, the material shallbe prepared from tlesh prawns characteristic in colourand shallbe flee from black discoloration. The materialshall be of the following four types:

a) Boiled, peeled and dried prawns;

b) Boiled, dried and deshelled prawns;

c) Peeled, boiled and dried prawns; and

d) Dried uncooked prawns shell-on.

Cooked material shall be prepared by cooking the wholeprawns/peeled prawns in brine. It is then dried.Alternatively, it shall also be prepared by peeling,cooking and then drying. Dried, uncooked, shell-onprawns are prepared by simple drying.

The strength of the brine shall be such that it shallnot impart too much saltiness to the material. The saltused shall conform to IS 594. The cooking time shallbe such that the shells get loosened from the meatand the material acquires a firm texture. The materialshall be dried either in the sun or in artificial driersunder hygienic conditions.

The limitsfor the presence of shell material in the cookedtypes and grades of the material shall be as follows:

a) Peeled, boiled :and dried prawns

b) Boiled, peeled :and dried prawns

c) Boiled, dried :and deshelled

Absent for all grades

Not more than 0.5 percentby mass

Large and mediumprawns grades — below1.0mrcent. Small and tinygra~es below 5.0 percentby mass

The limits for broken pieces of meat in the material shallbe as follows:

a) Peeled, boiled

I

Not more than 1.0and dried prawns

percent by mass for all

b) Boiled, peeled

I

grades

and dried prawns

/ ,—

. .d

{

-. ‘-“,

4.

,..,:

7

.4_.&

1s 14950:2001

c) Boiled, dried anddeshelled prawns

d) Dried, uncookedprawns withshell-on

Large and mediumgrades — below3.Opercent, small and tinygrades below 5.0percent by mass

C-6 DRIED SHARK FINS

In the case of dried shark fins, the dorsal, ventral andpectoral or caudal fins of edible sharks shall be usedfor the preparation of the product. The material shallbe prepared from fresh sharks. The fins maybe cut assoon as the sharks are landed. While cutting, avoidas much flesh as possible. Any flesh attached to thecut fins should be removed. The fin shall be washedwith clean water. The tins may be dusted with salt inthe ratio 1: 10( salt: fins). The cut portions maybedusted with salt and a little lime and treated fins shouldbe kept for 24 h, The fins should again be washed with

clean water and dried in the sun preferably by hangingon poles or ropes or by spreading on mats or by artificialdriers till the moisture is reduced to 10 percent. Thematerial shall not have salt or lime excrescence on thesurface.

C-7 FISH MAWS

Fish maws is prepared from the air bladder of fishes,such as cat fish, jew fish, eel and Indian salmon. Theair bladder afler removal shall be washed thoroughlyin clean water and shall be free from stains, bloodvessels, shreds, blood spots, etc. The material shallbe dried in the sun by spreading on drying racks/platforms or by artificial driers till a satisfactory productis obtained. Fish maws shall be in split, chunk or anyother form as agreed to between the purchaser andthe vendor. The material shall be well-dried not stickingto each other.

ANNEX D

[Tables 2 and 3, S1No. (i)]

DETERMINATION OF MOISTURE~

D-1 PREPARATION OF SAMPLE

Cut the large pieces into small size and mix. Grind thepieces as finely as possible preferably using an electricgrinder so that a homogeneous sample is obtained.Keep the material in an airtight container in order toprevent loss of moisture during subsequent handling.Use this material for testing.

D-2 PROCEDURE

Weigh about 5 g of the prepared (see D-1) sample intoa tared silica crucible or dish. Dry the dish in an air

oven at 100+ 1“C for 6 h. Cool in a desiccator andweigh. Retain the dried material for the determinationof sodium chloride ( see Annex E ) and acid insolubleash ( see Annex F ).

D-3 CALCULATIONM, x 100

D-3,1 Moisture percent by mass= ~2

where

Ml= loss in massing of the sample, and

M2= mass in g of the sample taken for test.

8

Is 14950:2001

ANNEX E

[ Tables 2 and 3, S1No. (ii)]

DETERMINATION OF SODIUM CHLORIDE

E-1 REAGENTS

E-1.1 Standard Silver Nitrate Solution —0.1 N.

E-1.2 Dilute Nitric Acid — 1:4..

E-1.3 Ferric Alum Indicator Solution

A saturated solution of ferric alum[Fe NH, (S0,)2.12 H,O].

E-1.4 Standard Potassium Thiocyanate Solution—0.1 N,

E-2 PROCEDURE

Take 1 to 2 g of the dried material ( see D-2.1 ) in a250-ml beaker and add 50 ml of distilled water tie fromchloride and heat on a water bath till all the sodiumchloride goes into solution. Filter in a 250-ml conicalflask and wash with distilled water, free from chloridetill the washings are free from chlorides. Add 20 ml ofdilute nitric acid and a known volume of standard silvernitrate solution, sutllcient to precipitate all the chlorides.Add 5 ml of nitrobenzene and shake vigorously for

2 min. Add 1ml of ferric alum indicator and titrate withstandard potassium thiocyanate solution until apermanent light brown colour appears.

E-3 CALCULATION

Sodium chloride (on moisture-free basis ),5.85 X (V,N, – V2N2)

p~rcent by mass =M

where

V,= Volume, in ml, of the standard solution ofsilver nitrate used;

Nl = Normality of the standard silver nitratesolution;

Vz = Volume, in ml, of the standard potassiumthiocyanate solution used;

N2 = Normality of the standard potassiumthiocydnate; and

M = Mass, in g, of the dried material taken forthe test.

ANNEX F

[ Tables 2 and3, SINO. (iii) ]

DETERMINATION OF ACID INSOLUBLE ASH

F-1 REAGENT

F-1.l Dilute Hydrochloric Acid — 1:1.

F-2 PROCEDURE

Weigh accurately about 2 g of the dried material( see D-2 ) in a tared porcelain, silica or platinumdish. Ignite with a Mekerbumer for about 1h. Completethe ignition by keeping in a muffle furnace at600 +20 ‘C until grey ash results. Cool and add 25 mlof dilute hydrochloric acid, cover with a watch glassand heat on water bath for 10 min. Cool and filterthrough Whatman filter paper No.42 or itsequivalent. Wash the residue with hot water until thewashings are free from chlorides as tested with silvernitrate solution and return the filter paper and residueto the dish. Keep it in an electric air oven maintainedat 135 + 2 ‘C for about 3 h. Ignite in a muffle furnace

at 600+20 “C for 1h. Cool in a desiccator and weigh.Ignite the dish again for 30 rein, cool and weigh. Repeatthe process till the difference between two successiveweighings is less than one milligram. Note the lowestmass.

F-3 CALCULATION

F-3.1 Acid insoluble ash (on moisture-free basis),100x( M2-M)

percent by mass =(MI-M)

where

Mz = Lowest mass, in g, of the dish with the acidinsoluble ash;

M = Mass, in g, of the empty dish;

Ml= Mass, in g, of the dish with the dried materialtaken for the test.

9

4J.L-

Bureau of Indian Standards

BIS is a statutory institution established under thelhmeau oflndian Standards Act, 1986 to promoteharmonious development of the aetitities of standardization, marking and quality certification of goods andattending to connected matters in t.lie country.

Copyright

BIS has the copyright of all its publications. Nopartof thesepublicatio~ maybe reproduce(l in anyform withoutthe prior permission in writing of BIS. This does not preclude the free use, in the course of implementing thestandard, of necessary details, such as symbols and sizes, type or grade designations. Enquiries relating tocopyright be addressed to the Director (Publications), BIS.

Review of Indian Standards :!

iiAmen@nents are issued to standards as the need arises onthebasis of comments. Standards are also reviewed $periodically; astandarcljalong with amendments is reaffkrned when such review indicateM.hat no changes areneeded; if the review indicates that changes are needed, it is taken up for revision. Users of Indian Standards i’/should ascertain that they are in possession of the latest amendments or edition by referring to the latest issue

1’

[’

of ‘BIS Catalogue’ and’ Standards: Monthly Additions’,

This Indian Standard has been developed from Doc : No. FAD 12 ( 911 ). (~/

Amendments Issued Since Publication

.,Amend No. Date of Issue Text AfTected

,.. .I1.

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