Final Test Manual Part I(16!08!2012)

8/12/2019 Final Test Manual Part I(16!08!2012)

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Food Safety and Standards Authority of India (FSSAI),FDA Bhavan, Kotla Road, New Delhi 110002 India.

EPABX: 011-23236975, Telefax: 011-23220994Eat Pure... Live Pure.....

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QUICK TEST FORSOME ADULTERANTS

IN FOOD 3TINSTRUCTION MANUAL- PART I (COMMONMETHODS FOR DETECTION AT HOUSEHOLDS)

3TFood is essential for nourishment and sustenance of l ife. Adulteration of food cheats the consumer and can pose serious risk to health in somecases. The purpose of this manual is to give the consumer an

opportunity to detect a few common adulterants in food. The manualcompiles testing methodology for common adulterants to be tested athouseholds

7TF OOD S AFETY ANDSTANDARDS A UTHORITY OF I NDIA

3T3/8/2012


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Quick Test For some Adulterants In Food- Instruction Manual Part 1

Eat Pure..... Live Pure....

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Adulteration of food Cheats the consumer and poses a serious risk to health. A common consumer may not havesufficient knowledge about purity and quality of food articles heconsumes. Mere visual inspection does not serve the purpose especiallywhen adulteration has assumed high degree of sophistication. With thisview Food Safety and Standards Authority of India has developedQUICK TEST FOR SOME ADULTERANTS IN FOOD which gives theconsumer to screen their day to day food articles.

This manual provides testing methods for common adulterants whichcan be easily performed in the households.


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Adulteration of food, a Deep Rooted Social Evil

Among mans everyday needs, food plays a major sustaining role. From thesimple dish to the most elaborate haute cuisine, food preparation is as varied and

rich as mans taste.

The lure of riches and general apathy towards mankind has led to adulterantsbeing added to food from the simple stones in rice to the more harmful brick andboric powder.

Adulteration of food commonly defined as the addition or subtraction of anysubstance to or from food, so that the natural composition and quality of foodsubstance is affected.

Adulteration is either intentional by either removing substances to food or alteringthe existing natural properties of food knowingly. Unintentional adulteration isusually attributed to ignorances, carelessness or lack of facilities for maintainingfood quality.

The common man, unfortunately, remains largely unaware of these adulterants andconsume food without thorough checks. Some of the common adulterated foodsare milk and milk products, atta, edible oils, cereals, condiments (whole and

ground), pulses , coffee, tea, confectionary, baking powder, non-alcoholic beverages,vinegar, besan and curry powder.

Adulteration of food cheats the consumer and can pose serious risk to health. Merevisual inspection does not serve the purpose especially when adulteration hasassumed high degree of sophistication. Consumer awareness is the remedy foreliminating the evil of adulteration and sale of substandard food article. The simpleand quick test which can be easily performed to ascertain the purity of a foodproduct are published here in view of the current food safety situation and hence,

Quick Test for some Adulterants in Food has been developed to protect thehouseholds/ small industries and common man in the country against foodadulteration.A set of two instruction manuals have been developed i.e. Part I and Part II. Part I incorporates simpletesting procedures which can be easily performed in the households and simplyhelp the consumer to screen their day to day food articles. Instruction manual Part IIhowever, incorporates testing procedures which require specific chemicals,reagents and glasswares and cover a wider range of adulterated food group. Thescope of this manual limits to small industries/ Food vendors / NGOs etc but fordetailed confirmatory test and quantification the analysis in a laboratory is a must


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and ground), pulses, coffee, tea, confectionary, baking powder, non-alcoholic beverages, vinegar, besan and currypowder.

Types of Adulterants:

Type Substances AddedIntentional Adulterants Sand, marble chips, stones, mud, other filth, talc, chalk powder, water, mineral oil

and harmful colour.Incidental adulterants Pesticide residues, droppings of rodents, larvae in foods.Metallic contaminants Arsenic from pesticides, lead from water, effluent from chemical industries, tin

from cans.

Poisonous or Deleterious Substances

Generally, if a food contains a poisonous or deleterious substance that may render it injurious to health, it isadulterated. For example, apple cider contaminated with E. coli O157:H7 and Brie cheese contaminated withListeria monocytogenes are adulterated.

If a food contains a poisonous substance in excess of a tolerance, regulatory limit, or action level, mixing it with"clean" food to reduce the level of contamination is not allowed. The deliberate mixing of adulterated food withgood food renders the finished product adulterated

Filth and Foreign Matter

Filth and extraneous material include any objectionable substances in foods, such as foreign matter (for example,glass, metal, plastic, wood, stones, sand, cigarette butts), undesirable parts of the raw plant material (such as

stems, pits in pitted olives, pieces of shell in canned oysters), and filth (namely, mold, rot, insect and rodent parts,excreta, decomposition

Economic Adulteration

A food is adulterated if it omits a valuable constituent or substitutes another substance, in whole or in part, for avaluable constituent (for instance, olive oil diluted with tea tree oil); conceals damage or inferiority in any manner(such as fresh fruit with food coloring on its surface to conceal defects); or any substance has been added to it orpacked with it to increase its bulk or weight, reduce its quality or strength, or make it appear bigger or of greatervalue than it is (for example, scallops to which water has been added to make them heavier).

Microbiological Contamination and Adulteration

The fact that a food is contaminated with pathogens (harmful microorganisms such as bacteria, viruses, orprotozoa) may, or may not, render it adulterated. Generally, for ready-to-eat foods, the presence of pathogens willrender the food adulterated. For example, the presence of Salmonella on fresh fruits or vegetables or in ready-to-eat meat or poultry products (such as luncheon meats) wi ll render those products adulterated.

For meat and poultry products, which are regulated by USDA, the rules are more complicated. Ready-to-eat meatand poultry products contaminated with pathogens, such as Salmonella or Listeria monocytogenes, areadulterated. For raw meat or poultry products, the presence of pathogens will not always render a product

adulterated (because raw meat and poultry products are intended to be cooked and proper cooking should killpathogens). Raw poultry contaminated with Salmonella is not adulterated.


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Methods for Detection of common adulterants in food

SNO FOOD ARTICLE ADULTERANT METHOD FOR DETECTION REMARKS1. Milk Water

(i) The presence of water can be byputting a drop of milk on a polishedslanting surface. The drop of puremilk either or flows lowly leaving awhite trail behind it, whereas milkadulterated water will flowimmediately without leaving amark,

2. Starch Add a few drops of tincture of

Iodine or Iodine solution.Formation of blue colour indicatesthe presence of starch.

Iodine solution iseasily available in

the medicalstores.

3. Urea Take a teaspoon of milk in a testtube. Add teaspoon of soybean orarhar powder. Mix up the contentsthoroughly by shaking the test tube.After 5 minutes, dip a red litmuspaper in it. Remove the paper after a minute. A change in colour fromred to blue indicates the presence of

urea in the milk.4. Vanaspati Take 3 ml of milk in a test tube. Add

10 drops of hydrochloric acid. Mix upone teaspoonful of sugar. After 5minutes, examine the mixture. Thered colouration indicates thepresence of vanaspati in the milk.

5. Formalin Take 10 ml of milk in a tests tube andadd 5 ml of con sulphuric acid fromthe sides of the wall without shaking.

If a violet or blue ring appears at theintersection of two layers then itshows presence of formalin.

Formalinenhances the lifeof milk and thus is

added forpreservationpurpose.

6. Detergent Shake 5-10 ml. of sample with anequal amount of water latherindicates the presence of detergent.

7. Milk Synthetic milk Synthetic milk has a bitter aftertaste, gives a soapy feeling onrubbing between the fingers and

turns yellowish on heating.

8. Synthetic milk- test for protein The milk can easily be tested by


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Urease strips (available in theMedical stores) because Syntheticmilk is devoid of protein.

9. Test for Glucose/inverted sugar

Milk does not contain glucose /invertsugar, if test for glucose with ureasestrip found positive. It means milk isadulterated.

If it is madesynthetically byadding whilecolour waterpaint. Oils, alkali,urea anddetergent etc.Glucose, invertedsugar syrup isadded in milk toincrease theconsistency andtest

10. Ghee, cottagecheese, condensedmilk, khoa, milkpowder etc,

Coal Tar Dyes Add 5 ml of dil. H 2 SO4 or conc. HCL toone teaspoon full of melted samplein a test tube. Shake well. Pink colour(in case of H 2 SO4 ) or crimson colour(in case of HCl) indicates coal tardyes. If HCl does not give colourdilute it with water to get the colour.

MILK AND MILKPRODUCTS

1. Sweet Curd Vanaspati Take1 teaspoon full of curd in a test tube.Add 10 drops of hydrochloric acid. Mix upthe contents shaking the test tube gently.After 5 minutes, examine the mixture. Thered colouration indicates the presence ofvanaspati in the curd.

2. Rabdi Blotting paper Take a teaspoon of rabri in a test tube. Add3 ml of hydrochloric acid and 3 ml ofdistilled water. Stir the content with a glassrod. Remove the rod and examine.Presence of fine fibres to the glass rod willindicate the presence of blotting paper inrabri.

3. Khoa anditsproducts

Starch Boil a small quantity of sample with somewater, cool and add -a few drops of Iodinesolution. Formation of blue colourindicates the presence of starch

4. Chhana orPaneer

Starch


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Mashed Potatoes,Sweet Potatoes andother starches.

The presence of mashed potatoes andsweet potatoes in a sample of ghee caneasily be detected by adding a few dropsof Iodine, which is brownish in colourturns to blue if mashed potatoes/sweetpotatoes/other starches are present.

3. Butter Vanaspati or

MargarineTake about one teaspoon full of meltedsample of butter with equal quantity ofconcentrated Hydrochloric acid in astoppered test tube and add to it a pinchof sugar. Shake for one minute and let itfor five minutes. Appearance of crimsoncolour in lower (acid) of Vanaspati or

Margarine.

The test isspecific forseasame oilwhich iscompulsorilyadded toVanaspati and

Mrgarine.Some coal tarcolours alsogive a positivetest.

If the test ispositive i.e.red colourdevelops onlyby addingstrongHydrochloricacid (withoutadding crystalsof sugar) thenthe sample isadulteratedwith coal tardye. If thecrimson or redcolourdevelops afteradding andshaking withsugar, thenaloneVanaspati orMargarine ispresent

4. Mashed potatoesother starches

The presence of mashed potatoes andsweet potatoes in a sample of butter caneasily e detected by adding a few drops ofiodine (which is brownish in colour), turnsto blue.

5. Edible oil Prohibited colour Take 5 ml of sample in a test tube and add


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5 ml of concentrated hydrochloric acid.Shake gently, let it stand for 5 minutes.Colour will separate in the upper layer ofthe solution.

6. Coconut oil Any other oil Place a small bottle of oil in refrigerator.Coconut oil solidifies leaving the adulterantas a Separate layer.

SWEETENING AGENTS

1. Sugar

Chalk powderDissolve 10 gm of sample in a glass ofwater, allow settling, Chalk will settledown at the bottom.

2. Urea On dissolving in water it gives a smell ofammonia.3.

Chalk powder Dissolve 10 gm of sample in a glass ofwater, allow to settle, chalk will settledown at the bottom.

4. ellow colour (Non-permitted)

Take 5 ml in a tests tube from the abovesolution and add a few drops of conc.Hcl. A pink colour in lower acid layersshows the presence of non- permitted

colour.5. Honey

Sugar solution A cotton wick dipped in pure honeywhen lighted with a match stick burnsand shows the purity of honey. Ifadulterated, the presence of water willnot allow the honey to burn, If it does;it will produce a cracking sound.

This test isonly foradded water.

6. Jaggery Washing soda Add a few drops of solution HCL.Effervesence shows presence of washingsoda.

7. jaggery Chalk powder Dissolve a little amount sample in waterin a test tube, chalk powder settlesdown.-Or-Add a few drops of conc Hcl solution,effervescence indicates the presence ofadulterant.

8. Metanil yellow colour Take of a teaspoon of the jaggery in atest tube. Add 3 ml of alcohol and shake

the tube vigorously to mix up thecontent. Pour 10 drops of hydrochloric


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acid in it. A pink colouration indicates thepresence of metanil yellow colours in

jaggery.9. Sugar solution Add a drop of honey to a gla ss if wa ter,

if the drop does not disperse in water it

indicates that the honey is pure.However, if the drop disperses in waterit indicates presence of added sugar.

10. Bura sugar Washing soda Add 1 ml o f HCl to a li ttl e of bu ra sugar.Effervescence occurs if washing sodais pre sent. Di ssolve 2 gm of sugar i nwater; dip a red litmus paper in thesolution. If washing soda is present, itwill turn blue.

11. Sweetmeats,Ice-creamandbeverages

Metanil yellow (a non-permitted coal tarcolour)

Extract colour with luke-warm waterfrom food articles. Add few drops ofconcentrated Hydrochloric acid. Ifmagenta red colour develops thepresence of metanil yellow isindicated.

Saccharin i. Taste a small quantity. Saccharinleaves a lingering sweetness on tonguefor a considerable time and leaves a

bitter taste at the end.

FOOD GRAIN AND THEIR PRODUCTS

1. Wheat, Rice,Maize, Jawar,Bajra, chana,Barley etc.

Dust, pebble,stone, straw,weed seeds,damaged grain,weevilled grain,insects, rodenthair and excreta

These may be examined visually to seeforeign matter, damaged grains,discoloured grains, insect, rodentcontamination etc.

Damaged /discolouredgrains shouldbe as low aspossible sincethey may beaffected byfungal toxins,argemoneseeds, Dhaturaseeds etc. Inmoderatelyexcessiveamount canresult in risk tohealth, Discardthe damaged


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undesirablegrains beforeuse

2. Maida Resultant atta orcheap flour

When dough is prepared from resultant orleft out atta, more water has to be used.The normal taste of chapattis prepared outof wheat is somewhat sweetish whereasthose prepared out of adulterated wheat

will taste insipid.3. Maida/ Rice Boric Acid Take a small amount of sample in a testtube, add some water and shake. Add afew drops of HCl. Dip a turmeric paper stripif i t turns red, boric acid is present.

4. Wheat bajraand othergrains

Ergot (a funguscontainingpoisonoussubstance)

(i) Purple black longer sized grains inBajra show the presence of Ergots.(ii) Put some grains In a glass tumblercontaining 20 per cent salt solution (20gm common salt to 100 ml water)purple

black longer size grain Ergot floats overthe surface while sound grains settledown.


DhaturaDhatura seeds are flat with edges withblackish brown colour which can beseparated out by close examination.


Karnel Bunt The affected wheat kernel have a dullappearance, blackish in colour and rottenfish smell,

7. Sella Rice(ParboiledRice)

Metanil yellow(a non-permittedcoal tar colour)

Rub a few grains in the palms of twohands. Yellow would get reduced ordisappear. Add a few drops of diluteHydrochloric acid to a few rice grainsmixed with little water, presence of pinkcolour indicates presence of Metanilyellow

8.


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Turmeric(colouring forgoldenappearance)

Take a small amount of sample in a testtube, add some water and shake.Dip Boric acid paper (filter paper dippedin Boric acid solution) If it turns pinkturmeric is present(ii) Take some rice and sprinkle on it asmall amount of soaked lime for sometime, grains will turn red if turmeric ispresent.

9. Parched rice Urea Take 30 numbers of parched rice in a testtube. Add 5ml of distilled water in it. Mix upthe contents thoroughly, by shaking the testtube. After 5 minutes, filter the water-contents, and add teaspoon of powder ofarhar or soybean in it. Leave it for 5minutes, and then dip a red litmus paper inthe mixture. Take out the litmus paper after30 seconds and examine it. A bluecolouration indicates the presence of ureain the parched rice.

10. Wheat flour Excess bran Sprinkle on water surface. Bran will float onthe surface.

11. Wheat flour Chalk powder Shake sample with dil. HCl Effervescenceindicates chalk.

Chalk powder isused as anadulterant due to

its weight.12.Dal wholeand spilt

Khesari Dal(i) Khesari dal has edged type appearanceshowing a slant on one side and square inappearance in contrast to other daIs.

13(ii) Add 50 ml of dilute Hydrochloric acidto the sample and keep on simmeringwater for about 15 minutes. The pink

colour developed indicates the presenceof Khesari dal.

The test is onlyfor Khesari dal.(Metanil

yellow ifpresent willgive a similarcolourimmediatelyeven withoutsimmering).

14.Clay, stone,gravels, webs,insects, rodent

hair and excreta

Visual examination will detect theseadulterants

Reject if thenumber ofInsects is large

or if the odouris unpleasant


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and tastebitter or gritty

15.Metanil yellow(a non permittedcoaltar colour)

Take 5 gms of the sample with 5 ml. ofwater in a test tube and add a few dropsof concentrated Hydrochloric acid. A pinkcolour shows presence o Metanil yellow

16.Atta, MaidaSuji (Rawa)

Sand, soil, insects,webs, lumps.rodent hair andexcrete

These can be identified by visualexamination.

17.Iron fil ings By moving a magnet through the sample,

iron fil ings can be separated.

18. Bajra Ergot infested Bajra. Soak bajra in water, swollen and black Ergotinfested grains will turn light in weight andwill float in water

Sago Sand or talcum Put a little quantity of sago in mouth, it willhave a gritty feel, if adulterated. Burn thesago, if pure, it will swell and leave hardlyany ash. Adulterated sago will leave behindappreciable quantity of ash.

19. Besan Metanil Yellow Take teaspoon of the besan in a test tube.Pour 3 ml of alcohol in the test tube. Mix upthe contents thoroughly by shaking the testtube. Add 10 drops of hydrochloric acid it. Apink colouration indicates presence ofmetanil yellow in the gram powder.

20. Khesari Flour Add 50 ml of dilute Hydrochloric acid to10 gms of sample and keep on simmeringwater for about 15 minutes. The pinkcolour, if developed, indicates, thepresence of Khesari flour

The test is onlyfor Khesari dal(Metanilyellow, ifpresent willgive a similarcolour evenwithoutsimmering).

21. Pulses Lead Chromate Shake 5 gm. Of pulse with 5 ml. Of

water and add a few drops of HCl. Pinkcolour indicates Lead Chromate.


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SPICES

1. Whole spices Dirt, dust, straw,

insect, damagedseeds, other seeds,rodent hair andexcrete

These can be examined visually.

2. Black pepper Papaya seeds Papaya seeds can be separated out

from pepper as they are shrunken,oval in shape and greenish brown orbrownish black in colour.

3. Light black pepper Float the sample of black pepper inalcohol (rectified spirit). The blackpepper berries sink while the papayaseeds and light black pepper float.(ii) Press the berries with the help offingers light peppers will break easilywhile black berries of pepper will notbreak.

4. Coated with

mineral oil

Black pepper coated with mineral oil

gives Kerosene l ike smell.

5. Cloves Volatile oil

extracted(exhausted cloves)

Exhausted cloves can be identified byits small size and shrunken appearance.The characteristic pungent of genuinecloves is less pronounced in exhaustedcloves

6. cloves Coated with mineraloil

Cloves coated with mineral oil giveskerosene like smell

7. Mustard seed Argemone seed Mustard seeds have a smooth surface

The argemone seed have grainy andrough surface and are black and hencecan be separated out by closeexamination. When Mustard seed ispressed inside it is yellow while forArgemone seed it is white

Use magnifyingglass foridentification.

8. Powderedspices

Added starch Add a few drops of tincture of Iodine orIodine solution. Indication of blue colourshows the presence of starch.

Iodine test foradded starch is notapplicable for


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turmeric powder.

9. Powderedspices

Common Salt Taste for addition of common salt.

10. Turmericpowder

Coloured saw dust Take a tea spoon full of turmericpowder in a test tube. Add a fewdrops of concentrated Hydrochloricacid. Instant appearance of pinkcolour which disappears on dilutionwith water shows the presence ofturmeric If the colour persists, metanilyellow (an artificial colour) a notpermitted coal tar colour is present.

This test is onlyfor Metanilyellow

11. Turmeric whole Lead chromate Appears to be bright in colour whichleaves colour immediately in water.

12. Chalk powder oryellow soap stonepowder

Take a small quantity of turmericpowder in a test tube containingsmall quantity of water. Add a fewdrops of concentrated Hydrochloricacid, effervescence (give offbubbles) will indicate the presenceof chalk or yellow soap stonepowder

13. Chillies powderBrick powder, saltpowder or talc,powder

Take a tea spoon full of chillies powderin a glass of water. Coloured waterextract will show the presence ofartificial colour.

This test is onlyfor earthymaterial


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Any grittiness that may be felt onrubbing the sediment at the bottom ofglass confirms the presence of brickpowder/sand, soapy and smoothtouch of the white residue at thebottom indicates the presence of soapstone.

To a little powder of chilli add smallamount of conc HCl and mix to theconsistency of paste, dip the rear endof the match stick into the paste andhold over the flame, brick red flamecolour due to the presence of calciumslats in brick powder.

14. Artificial colours Sprinkle the chilli powder on a glass ofwater. Artificial colorants descend ascoloured streaks.

15. Water soluble coaltar colour

Water soluble artificial colour can bedetected by sprinkling a smallquantity of chillies or turmeric powderon the surface of water contained in aglass tumbler. The water solublecolour will immediately startdescending in colour streaks

16. Asafoetida

(Hing)Soap stone or otherearthy material

Shake little portion of the sample withwater and allow to settle. Soap stoneor other earthy mailer will settledown at the bottom.

In compoundedasafoetida dueto presence ofstarch, a slightturbid solutionmay beproduced.However, thiswill settle downafter keeping

17.

Starch Add tincture of iodine, appearance ofblue colour shows the presence ofstarch.

Compound ofasafoetida containsstarch which isdeclared on thelabel. This test isnot applicable forcompoundasafoetida.

18. Foreign resin Burn on a spoon, if the sample burns likecamphor, it indicates the sample is pure.

Pure hing burnslike aromaticcamphor

19. Spices Powdered bran andsaw dust

Sprinkle on water surface. Powderedbran and sawdust float on the surface.


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20. Cinnamon Cassia bark Cinnamon barks are very thin and can berolled. It can be rolled around a pencil orpen. It has a distinct smell. Whereascassia ark comprise of several layers inbetween the rough outer and inner mostsmooth layers. On examination of theark loosely, a clear distinction can bemade.

21. Cumin seeds Grass seeds colouredwith charcoal dust

Rub the cumin seeds on palms. If palmsturn black adulteration is indicated.

22. Green chilli andgreenvegetables.

Malachite green Take a cotton piece soaked in liquidparaffin and rub the outer green surfaceof a small part of green vegetable. If thecotton turns, green, we can say thevegetable is adulterated with malachite

green.

23. Green peas Artificially coloured Take a little amount of green peas in a250 ml beaker add water to it and mixwell. Let it stand for half an hour. Clearseparation of colour in water indicatesadulteration.

24. Saffron Dried tendrils of

maizecobGenuine saffron will not break easilylike artificial. Artificial saffron isprepared by soaking maize cob in

sugar and colouring it with coal tarcolour. The colour dissolves in water ifartificially coloured. A bit of puresaffron when allowed to dissolved inwater will continue to give its saffroncolour so long as it lasts

MISCELLENIOUS PRODUCTS

1. Common

saltWhite powdered Stir a spoonful of sample of salt

in a glass of water. Thepresence of chalk will makesolution white and otherinsoluble impurities will settledown.

2. Iodized salt Common salt Cut a piece of potato, add salt and wait

minute and add two drops of lemon juice. If iodized salt blue colour will


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develop. In case of common salt, therewill be no blue colour.

3. Tea

leavesExhausted tea Take a fil ter paper and spread a few tea

leaves. Sprinkle with water to wet the

filter paper. If coal tar colour is present itwould immediately stain the filter paper.Wash the filter paper under tap water andobserve the stains against light

Spread a little slaked lime on whiteporcelain tile or glass plate; sprinkle a littletea dust on the lime. Red, orange or othershades of colour spreading on the lime willshow the presence of coal tar colour. Incase of genuine tea, there will be only a

slight greenish yellow colour due tochlorophyll, which appear after some time.

4. Iron fill ings By moving a magnet through the sample,iron fill ing can be separated.

5. Chicory Gently sprinkle the coffee powder

sample on the surface of water ina glass. The coffee floats over thewater but chicory begins to sinkdown within a few seconds. Thefalling chicory powder particlesleave behind them a trail ofcolour, due to large amount ofcaramel

6. Supari

PanMasala

Colour

Colour dissolves inwater7.

Saccharin Saccharin gives excessive andlingering sweet taste and leavesbitter taste at the end.

8. Catachupowder

Chalk Chalk gives effervescence (givesoff bubbles) with concentratedHydrochloric acid

This test is onlyfor Chalk.

9. Lemonadesoda

Mineral acid Pour 2 drops of the lemonade soda on ametanil yellow paper- strip. A violetcolouration indicates the presence of


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mineral acid in aerated water. The colourimpression gets retained even after dryingthe paper (you can prepare metanil yellowpaper strips by soaking filter paper strips in0.1 % aqueous solution and then drying the

paper strips).10. Sweet Potato Rhodamine B colour Take a cotton piece soaked in liquid

paraffin, and rub the outer red surfaceof the sweet potato. If the cottonabsorb colour, it indicates the use ofrhodamine B colours on the outersurface of the sweet potato.

11. Pulses Lead Chromate Shake 5 gm. Of pulse with 5 ml. Ofwater and add a few drops of HCl. Pink

colour indicates Lead Chromate.12. Iodized salt Common salt Cut a piece of potato, add salt and wait

minute and add two drops of lemon juice. If iodized salt blue colour willdevelop. In case of common salt, therewill be no blue colour.

13. Silver leaves Aluminium leaves

(i). On ignition, genuine silverleaves burn away completely,leaving glistering white spherical

ball of the same mass whereasaluminium leaves are reduced toashes of dark grey blackish colour.(ii), Take silver leaves in test tube,add diluted Hydrochloric acid.Appearance of turbidity to whiteprecipitate indicates the presenceof silver leaves. Aluminium leavesdo not give any turbidity orprecipitate.

(iii) Take aluminium leaves in palmand rub between both the palms ofthe hand, silver leaves completelydisappear in the hand; howeverpresence of small ball in the palmindicates adulteration withaluminium leaves.

14. Vinegar

Mineral Acid

Test with the Metanil yellow indicatorpaper, in case, the colour changes fromyellow to pink, mineral acid is present


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ANNEXURE I

Reagents in Instruction manual Part I

REAGENT NO. CHEMICAL

1. Conc HCL.2. Tincture of Iodine3. Iodine solution4. Conc Sulfuric Acid.5. Liquid Paraffin.6. Slake Lime (Chuna)

7. Boric Acid.8. Metanil yellow colours.9. Red litmus paper.10. Urease strip11. Alcohol.12. Carbon tetra chloride

Apparatus in the Instruction Manual Part I

1.

Test Tubes2. Burner3. White Tile4. Filter paper 5. Magnet. 6. Test tube holder 7. Glass cylinder 8. Dropper 9. Spatula 10. Magnifying glass


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Annexure IIPRECAUTIONS TO BE TAKEN

Chemical no: 1,2,3,4 are corrosive use gloves and handle with care. Chemical No 11 is highly inflammable. Keep away from fire. Chemical No: 6- avoid inhalation. Always keep the chemicals away from the reach of children.

In case of spillage of chemical reagents on body or cloth, wash with plenty ofcold water till the reagent is completely washed away.


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Final Test Manual Part I(16!08!2012)

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Transcript of Final Test Manual Part I(16!08!2012)