Quality testing of spices mainly chemical method of testing are covered

1. QUALITY TESTING OF
SPICES
V.SUNDARALAKSHMI
2014027036

2. Spices are added to food in small amounts but they make important
contribution to the sensory qualities due to the presence of volatile oils
and fixed oils.
Volatile oil example: clove oil, cardamom oil, cinnamon oil, nutmeg oil
Non-volatile oil example: spice oleoresin(contains volatile and non-
volatile constituents), palm oil, linoleic acid, linolenic acid.

3. Preparation of samples for proximate analysis
Grind the sample in a grinding mill to pass sieve with 1 mm
diameter aperture.
Reference: IS Specification No IS 1797 – 1985 Methods of
Test for Spices and Condiments/ AOAC 17th edition 2000,
Official Method 920.164 Preparation of Test sample).

4. Determination of moisture
The determination of moisture is one of the important aspects in
processing and quality testing of spices, since it is an index of
stability.

5. Determination of Moisture
Method of analysis:
Dean and Stark Toluene Distillation Method Karl Fischer Method
 The amount of water is determined by distilling the
material with an organic liquid not miscible with water
and collecting the distillate in a graduated tube.
 Simple distillation method is followed to determine the
water content in spices.
REAGENT: TOULENE
Moisture Content(% by weight) = 100V
M
Where, V = Volume in ml of water collected
M = Weight of sample
 REFERENCE: AOAC 17th edition 2000 Official
Method 986.21, Moisture in Spices/IS Specification
No IS 1797 – 1985 Methods of Test for Spices and
Condiments
 Karl Fischer Method is designed to determine water
content in substances.
 In the Volumetric Titration Method, water content is
determined by measuring the amount of iodine
consumed as a result of reaction with water in a
sample.
 REFERENCE: J. AOAC Int. 85, 318 (2002)

6. Reflux
condenser
Graduated tube
Flask
Dean and Stark toluene distillation
apparatus

7. Determination of total ash:
 This is a measure of the level of impurities in a product, obtained by burning off
the organic matter and measuring the residue of ash.
 Ashing is also recognised as a useful tool in determining the extent of mineral
constituents.
 This measurement is carried out by incinerating the herb or spice in muffle
furnace at 550ºC to constant weight.
Where, W = wt in gm of empty dish(g)
W1 = wt in gm of dish + sample (g)
W2 = wt in gm of dish + total ash (g)
M = Percent moisture content
(Reference: IS Specification No IS 1797 – 1985 Methods of Test for Spices and
Condiments/ AOAC 17th edn , 2000 Official Method 941.12 Ash of Spices)
Total ash on (dry basis) % by wt = (W 2 – W) x 100 x 100
W1 – W 100-M

8. Determination of Ash insoluble in dilute HCl :
 This determination helps in showing added mineral matter such as dirt or sand in
spices.
 Acid-insoluble ash(AIA)consists of indigestible mineral components, mainly
silica. AIA content of spice increases due to the addition of exogenous sources
of AIA such as sand. Therefore AIA content of the spice should be low.
PROCEDURE:
Incinerating the residue in muffle furnace (again at 550ºC) to a
constant weight.
The undissolved residue left is quantitatively filtered, and
Dissolve in 25 ml of dilute HCl and
Residue left behind in the determination of total ash

9. CALCULATION:
Where, W = wt of empty dish(g)
W1= wt of dish + sample (g)
W4 = wt of dish + acid insoluble ash (g)
M = Percent Moisture content
(Reference: IS Specification no IS 1797 – 1985 Methods of Test for Spices and
Condiments/ AOAC 17th edn 2000, Official Method 941.12 (b) Ash of Spices)
Ash insol. in dil HCl (on dry basis) % by wt = (W 4 – W) x 100 x 100
W1 – W 100 – M

10. Water-soluble ash determination:
 This helps in determining the added mineral matter and interpretation of
analysis of spices for their quality.
 Most of the mineral constituents are water soluble except silica. So water
soluble content of the spice should be high than that of AIA content.
 If the total ash and the water soluble ash are very low then probably the
chance of adulteration is high in the spice.
PROCEDURE:
measure the residue.
incinerate in muffle furnace at 550°C
evaporate the water carefully on a water bath
add distilled water,
To the reserved ash,

11. CALCULATION:
 Where M0 = Mass in g. of the empty dish
 M1 = Mass in g. of the dish and sample.
 M3 = mass in g. of the dish and water-soluble ash.
 H = moisture content of the sample in percentage.
(Reference: IS Specification no IS 1797 – 1985 Methods of Test for Spices and
Condiments/ AOAC 17th edn 2000, Official Method 941.12 (a) Ash of Spices)
Water-soluble ash(on dry basis)% by weight = (M3-M0) X 100/M1-M0 X
100/100-H

12. Non-volatile ether extract determination(NVEE):
 The non-volatile ether extract constitutes the non-volatile ether extractable matter
or fixed oil, etc.
 Chemically, NVEE contains the entire fixed oil, saponifiable as well as
unsaponifiable matter(USM).
 The USM contains sterols, pigment, waxes, fat soluble vitamins and alkaloids.
 This ethereal extract is desolventised under reduced pressure and residue is
called NVEE.

13. PROCEDURE:
Dry the flask until the loss in weight is less than 2mg.
Shake the residue with 2 ml diethyl ether at room temperature and is allowed
to settle and decant the ether. Repeat this until no more residue dissolves.
Weigh the flask until the loss in weight between the successive weighing is
less than 2mg.
Remove the ether by distillation followed by boiling the flask on a water bath
and drying it in an oven at 110°C
Extract 2 g of ground sample in a continuous extraction apparatus(soxhlet
extractor) with diethyl ether for 18 hours.

14. CALCULATION:
Where,W1 = Wt. of the flask wit non-volatile ether extract.
W2 = Wt. of the flask with ether insoluble residue after decantation.
W = wt. of the sample taken for test.
Reference: (BIS 1985 and IS Specification No IS 1797 – 1985 Methods of Test for
Spices and Condiments)
Non-volatile ether extract (% by weight) =100(W1-W2)/100

15. Determination of Volatile Oil:
 The determination of volatile oil in a
spice is made by distilling the spice
with water, collecting the distillate in a
graduated tube in which the aqueous
portion of the distillate is automatically
separated and returned to the distilling
flask, and measuring the volume of the
oil.
 Steam distillation is followed to
determine volatile oil in spices.
 The content of volatile oil is
expressed as a percentage v / w.
(Reference: FAO Manual of Food
Quality Control (1986)14 / 8 page 239)
/ AOAC 17th edn,2000 Official Method
962.17 and IS 1797 – 1985)

16.  Clevenger’s apparatus is a universally accepted as a official method for
determination of volatile oils in spices.
 Volatiles oils is insoluble in water so it is obtained by steam distillation.
PROCEDURE:
Note down the readings obtained.
Cool to 20˚C by immersing it in a suitable water bath
Reflux rate of 1 to 2 drops per second.
Heat the flask to boiling
Add 500 ml of water
Transfer it to the flask
Weigh the sample that could yield about 2 to 5 m of oil

17. Determination of crude fibre:
 The determination is based on acid and alkali hydrolysis and measurement of the residual
insoluble portion after proper ashing and weighing.
 The sample is treated with boiling dilute H2SO4, boiling dilute NaOH solution under
standardized condition. The organic residue remains is weighed and reported as crude
fibre.
 Helps in quality assessment and detection of adulteration of ground spices and spice
mixture with added cellulose material like twigs and cellulose powder.
Where, W1 = Wt. of gooch crucible + contents + asbestos before ashing (g)
W2 = Wt. of gooch crucible + ash and asbestos after ashing (g)
W = Wt. of sample taken for test (g)
M = Percent moisture content
(Reference: - IS Specification No IS 1797 – 1985 Methods of Test for Spices and
Condiments)
Crude fibre (on dry basis) (% by weight) = 100 (W1 – W2) x 100
W 100 – M

18. SPICE MOISTURE
CONTENT
%W/W
(MAX)
TOTAL ASH
CONTENT
%W/W
(MAX)
ACID
INSOLUBLE
ASH %W/W
(MAX)
VOLATILE OIL
ml/100g
(MIN)
CARDAMOM 12 9 2.5 4
CHILLI 11 1O 1.6 -
CINNAMON 14 7 2 0.72-1.0
CLOVE 12 7 0.5 14
CUMIN 13 14 3 1.5
CORIANDER SEED 12 7 1.5 0.6
FENNEL 12 10 2 1.5
FENUGREEK 11 7 1.5 TRACES
GINGER 12 8 2 1.5
MUSTARD 10 6.5 1 -
NUTMEG 10 3 0.5 5-6.5
PEPPER 12 7 1.5 2
SAFFRON 12 8 1 -
TURMERIC 12 8 2 2.5
SOURCE: ESA QUALITY MINIMA DOCUMENT

19. Determination of Extraneous Matter and other Refractions in Whole spices
Thoroughly mix the sample and weigh 100 – 200 gm depending on the nature of
the material (10 – 20 gm in case of small sized spices), note down the exact
weight and spread in an enameled tray. Separate extraneous matter and other
refractions by hand. Weigh each fraction and calculate percentage.
(Reference: IS Specification No IS 1797 – 1985 Methods of Test for Spices and
Condiments)

20. These methods will ensure repeatability and reproducibility of a test or
analysis thereby facilitating smooth operation of export-import trade and
reducing disputes. It will also help in grading of Spices and Condiments by
the statutory authorities.

21. THANK YOU…….