MANUAL ON STANDARDS OF MAIZE
1. INTRODUCTION
Promotion
of standardization and grading of agricultural commodities is an important
aspect of agricultural marketing. The agricultural commodities are
heterogeneous and hence it is very essential to grade these commodities as per
standards to command better price either at domestic or international market. Sale of Maize is offered on the basis of
variety, wholesomeness, appearance, colour, presence of foreign matter, damaged
grains, broken grains, admixture of inferior variety, moisture, harmful
contaminants, etc. A quality grain is
that which meets the end user specifications with respect to range of pre-determined
Quality and Safety standards.
2. OBJECTIVE
The
Manual has been designed with the objectives to
(i)
Create
awareness about standards prescribed by various organizations for domestic and
international markets so as to raise quality consciousness among the farmers,
entrepreneurs and other market functionaries with the objective to equip them
better to face the global competition in the post WTO era.
(ii)
provide
details of various parameters responsible for quality; and
(iii)
describe
the advantages of grading & standardization so that farmers may get prices
commensurate with the quality produced by them.
3. IMPORTANT PARAMETERS RESPONSIBLE FOR QUALITY
3.1 Following Parameters are important in determination of QUALITY
of Maize
·
Foreign
matter(organic and inorganic)
·
Damaged
grains
·
Immature/Shriveled
grains
·
Weevilled
grains
·
Other
edible grains
·
Admixture
of different varieties
·
Moisture
content
3.2 Following SAFETY parameters are important:
·
Residue of Pesticides
·
Poisonous/Heavy metals
·
Aflatoxin
·
Uric acid
·
Microbial
load
3.3 Parameters by which grades of Maize are differentiated:
Important parameters by which
grades can be differentiated in case of Maize are
4. STANDARDS APPLICABLE FOR PURCHASES BY FOOD CORPORATION OF
4.1 The main objectives
of the FCI are
(a) Effective price support operations for
safeguarding the interests of the farmers.
(b)
Distribution of food grains
throughout the country for Public Distribution system and other Govt. of India
schemes, and
(c)
Maintaining satisfactory
level of operational/buffer stocks of food grains to ensure national food
security.
4.2 To meet these
obligations, the FCI make purchases of Maize and for this purpose following standards for all varieties of Maize
are applicable (Marketing Season 2005-06)
The Maize shall be the dried and matured grain of Zea mays. The grain shall have uniform size, shape and
colour. It shall be in sound
merchantable condition and shall conform
to standards framed under Prevention of
Food Adulteration Rules.
SCHEDULE OF SPECIFICATIONS
S.No Refractions
Maximum Limit (%)
1 Foreign
matter* 1.0
2 Other foodgrains 2.0
3 Damaged
grains 1.5
4 Slightly
damaged, discoloured and 4.5
touched grains
5 Shrivelled
& Immature grains 3.0
6 Weevilled
grains 1.0
7 Moisture
14.0
* Not more than 0.25% by weight shall be
mineral matter and not more than 0.10% by weight shall be impurities of animal origin.
N.B:
3. Within the overall limit of 1.0% for
foreign matter, the inorganic matter shall not exceed 0.25% and poisonous
seeds too shall not exceed 0.5% of which Dhatura and Akra Seeds (Vicia species) not to exceed 0.025% and 0.2%
respectively.
DEFINITIONS:
Foreign Matter : Includes inorganic
and organic matter. The inorganic matter
shall include sand, gravel, dirt, pebbles, stones, glass and metallic pieces,
lumps of earth, clay and mud. Organic
matter shall include husk, chaff, straw, weed seed and other inedible
grains.
Other
Foodgrain
: food grains other than the grain under
consideration.
Damaged : Kernels or pieces of
kernels that are sprouted or internally damaged as a result of heat, moisture,
weather or microbes.
Slightly damaged or touched : Kernels or pieces of kernels that are damaged or discoloured, superficially so as not to affect the quality of the
material.
Discoloured: Kernels or pieces of kernels that have changed
the colour as a result of deteriorative changes.
Brokens : Pieces of sound kernels that are less than three-fourths of the size of the full kernels. In case of dals, pieces that are less than the size of
three-fourths of the split pulses shall be considered as brokens.
Immature : Kernels or pieces of
grain kernels that are not fully developed.
Weeviled Grains : Weeviled grains are grain kernels that are partially or wholly bored by insects injurious to grain but do not include germ-eaten grains
and egg-spotted
grains.
Moisture: The loss in mass caused as a result of heating for two hours at 130 to 133 degree centigrade under specified conditions and expressed as
percentage,
5. STANDARDS APPLICABLE
FOR STORAGE OF MAIZE
5.1 CENTRAL WAREHOUSING CORPORATION (CWC) : The CWC works as an
agent of the government for purchase,
sale, storage and distribution of agricultural and industrial commodities,
seeds, fertilizers and notified commodities for individual, cooperatives and
other institutions in the country. CWC
provides modern efficient warehousing to ensure maximum returns to the growers
with better opportunities. It provides scientific facilities to the farmers for
the stock of agricultural produce at a reasonable cost. CWC issues Warehouse Receipts to a person
depositing goods in the warehouse. The
banking institutions accept the Warehouse Receipts as co-lateral security for
grant of loans to the holder of the Warehouse Receipt on its being endorsed and
delivered to them. Thus, warehousing
plays an active role in marketing and also provides socio-economic gains to the
farmers, who otherwise get exploited by the middlemen and are forced to have
distress sales.
5.1.1 Standards of
Central Warehousing Corporation
Central
Warehousing Corporation follows standards given in item 4.2 for accepting Maize
for storage in Warehouses.
Central Warehousing Corporation has following
categorization for deciding the period of storability of Maize in the Warehouses.
Percentage
of Weevilled grains :
Up
to 1% A
Above
1% up to 4% B
Above
4% up to 7% C
Above
7% up to 15% D
In order to have better
storability of maize, farmers are advised to ensure that maize for storage has
Weevilled grains less than 1% (by count).
6. STANDARDS APPLICABLE FOR DOMESTIC MARKET
6.1 The Prevention of Food Adulteration Act, 1954 (PFA
Standards)
Prevention of Food Adulteration Rules, 1955 (PFA Rules) have been
notified to carry out the provisions of the Prevention of Food Adulteration
Act, 1954. These Rules define the standards of quality and fix the limit of
variability permissible in respect of article of food. These Rules also provide
guidelines for packing and labeling of an article of food. Standards framed
under the provisions of the Rules are popularly called PFA standards. PFA
standards prescribe minimum limit for Quality as well as Safety parameters. PFA
standards are minimum standards and are
mandatory. However, they do not differentiate between Quality. Food articles being sold in the
market should comply with PFA standards.
Standards of Maize
prescribed in PFA Rules, 1955 are as follows :
6.1.1. QUALITY PARAMETERS:
Description: Maize shall be the dried mature grains of Zea mays Linn. It shall be sweet, hard, clean and wholesome. It shall also conform to the
following standards, namely :-
(i)
Moisture
- Not more than 16.0 per cent by weight (obtained
by heating the pulverized grains at 130 C – 133 C for two hours).
(ii) Foreign matter - Not more than 1 per cent by weight of
which not more
Extraneous matter)
than 0.25 per cent by weight shall be mineral
matter . and not more than 0.10 per cent by weight
shall be
impurities of animal origin .
(iii) Other edible grains -
Not more than 3 per cent by weight.
(iv) Damaged
grains - Not more than 5 per cent by weight
(v) Weevilled
grains - Not more than 10 per cent by count
Provided that the total
of foreign matter, other edible grains and damaged grains shall not exceed 9
per cent by weight.
6.1.2 SAFETY PARAMETERS:
Uric Acid: Not
more than 100 mg. per kg.
Aflatoxin: Not
more than 30 micrograms per kg.
Limits for
insecticides and pesticides
Following
maximum limits are prescribed for residues of insecticides and pesticides
|
Sl.No. |
Name of insecticides |
Tolerance Limit mg/kg.
(p.p.m) |
|
1. |
Alachor |
0.10 |
|
2 |
Aldrin, dieldrin, (The
limits apply to aldrin and dialdrin singly or in any combination and are
expressed as dieldrin) |
0.01 |
|
3 |
Benomyl |
0.50 |
|
4 |
Carbaryl |
0.50 |
|
5 |
Chlordane (residue to be
measured as cis plus trans chlordane) |
0.02 |
|
6 |
Chlorfenvinphos (residues
to be measured as alpha and beta isomers of chlorfenvinphos) |
0.025 |
|
7 |
Chlorpyrifos |
0.05 |
|
8 |
Carbendazim |
0.50 |
|
9 |
Carbofuran(Sum of
carbofuran and 3-hydroxy carbofuran expressed as carbofuran) |
0.10 |
|
10 |
Diazinon |
0.05 |
|
11 |
Dichlorvos (Content of
dichloracetaldehyde (D.C.A) be reported where possible |
1.0 |
|
12 |
Decamethrin/Delta methrin |
0.50 |
|
13 |
2,4-D |
0.01 |
|
14 |
Dithiocarbamates(The
residue tolerance limits are determined and expressed at mg/CS2/kg and refer
separately to the residues arising from any or each groups of
dithiocabamates; (a) Dimethyl
dithiocarbamates residue resulting from the use of ferbam or Ziram, and (b) Ethylene bis
dithiocarbamates resulting from the use of mancozeb maneb or Zineb(including
Zineb derived from nabam plus Zinc sulphate) |
0.20 |
|
15 |
Diuron |
0.50 |
|
16 |
Ethion (Residues to be
determined as ethion and its oxygen analogue and expressed as ethion) |
0.025 |
|
17 |
Fenitrothion |
0.02 |
|
18 |
Fenthion (Sum of fenthion, its oxygen analogue and
their sulphoxides and sulphones, expressed as fenthion) |
0.10 |
|
19 |
Heptachlor (combined residues of heptachlor and epoxide
to be determined and expressed as heptachlor) |
0.01 |
|
20 |
Hexachlorocyclohexane and its isomers(Gamma isomer known as
Lindane) |
0.10 |
|
21 |
Hydrogen cyanide |
37.5 |
|
22 |
Inorganic bromide
(determined and expressed as total bromide from all sources) |
25.0 |
|
23 |
Malathion (Malathion to be
determined and expressed as combined residue of malathion and malaoxon) |
4.0 |
|
24 |
Metalyxyl |
0.05 |
|
25 |
Monocrotophos |
0.025 |
|
26 |
Oxydemeton methyl |
0.02 |
|
27 |
Paraquat-Dichloride(Determined
as paraquat cations) |
0.1 |
|
28 |
Phosphamidon residues
(expressed as the sum of phosphamidon and its desethyl derivative). |
0.05 |
|
29 |
Phenthoate |
0.05 |
|
30 |
Phorate (sum of phorate,
its oxygen analogue and their sulphoxide and sulphones, expressed as phorate) |
0.05 |
|
31 |
Pirimiphos-methyl |
5.00 |
|
32 |
Trichlorfon |
0.05 |
|
33 |
Thiometon (residues
determined as thiometon its sulfoxide and sulphone expressed as thiometon) |
0.025 |
Poisonous
Metals:
Following limits are prescribed for poisonous metals
Name of the parts
per million
Poisonous metal by weight
1 Lead 2.5
2 Copper 30.0
3 Arsenic 1.1
4 Tin 250.0
5 Zinc 50.0
6 Cadmium 1.5
7 Mercury 1.0
8 Methyl Mercury 0.25
(Calculated as the element)
7. STANDARDS FOR GRADING :
7.1 GRADING - Grading provides
description of the quality of the consignment and assists in the formation of a
legally binding agreement. It facilitates proper marketing of agricultural
commodities. It also ensures that
agricultural commodities move through the market faster and without obstructions. This also facilitates transactions without
physical verification by the distant buyers.
Advantages of Grading:
-
It brings confidence between the buyer and
the seller.
-
It facilitates interstate and
international marketing.
-
Disputes in the market can be solved
amicably.
-
Stability of the price is ensured.
-
Farmers can take loans easily from the
banks on the basis of grades of produce stored in the godown
-
Arbitrary fixation of price by middlemen
is eliminated.
-
Brings about improvement of the crop.
-
Reduces risk of producer and seller in
transactions.
-
Future marketing is facilitated. Grades
become a commercial measure of quality.
- It also helps in implementation of
contract farming.
7.2. AGRICULTURAL
PRODUCE (GRADING & MARKING) ACT, 1937 (AGMARK STANDARDS).
Standards of various
agricultural commodities prescribed under the provisions of the Agricultural Produce (Grading & Marking)
Act, 1937 are popularly known as AGMARK Standards. AGMARK standards comply with minimum
standards of quality & safety prescribed in Prevention of Food Adulteration
Rules, 1955. In addition AGMARK
standards differentiate between quality by having four grades for Maize . The grades are differentiated on the basis of
moisture, foreign matter, other edible grains, admixture of different
varieties, damaged grains, immature and shriveled grains, weevilled grains etc.
7.2.1 AGMARK
Standards of Maize:
Grade designation and definition of quality of Maize
Grade Definition of quality
designation --------------------------------------------------------------------------------------------------------------------------------
Special requirements
--------------------------------------------------------------------------------------------------------------------------------
Maximum limit of tolerance
(per cent by weight)
--------------------------------------------------------------------------------------------------------------------------------
Foreign matter
-----------------------------------
Moisture Organic Inorganic Other Admixture Damaged Immature and Weevilled
edible of different grains Shrivelled grains
Grains varieties grains (per cent by
Count)
1 2 3 4 5 6 7 8 9
Grade I 12.0 0.10 Nil 0.5 5.0 1.0 2.0 2.0
Grade – II 12.0 0.25 0.10 1.0 10.0 2.0 4.0 4.0
Grade –
III 14.0 0.50 0.25 2.0 15.0 3.0 6.0 6.0
Grade – IV 14.0 0.75 0.25
3.0 15.0 4.0 6.0 8.0
General
requirements
10
Maize
Shall :-
(a) be the dried mature grain of Zea mays L.;
(b) be sweet, hard, clean, wholesome, uniform
in size, shape, colour and in sound merchantable condition;
(c) be
free from added colouring matter, moulds, weevils, obnoxious substances,
discolouration, poisonous seeds and
all other impurities except to the extent indicated in the schedule;
(d) uric
acid and aflatoxin shall not exceed 100 milligrams and 30 micrograms per
kilogram respectively;
(e)
be free from rodent hair and excreta;
(f) comply with the restrictions in regard to
pesticides/insecticides residue (Rule 65), poisonous metals (Rule 57), naturally occurring toxic substances
(Rule 57-B) and other provisions prescribed under the Prevention of Food
Adulteration Rules, 1955 and as amended from time to time.
Note: In foreign matter, the impurities of animal origin
shall not be more than 0.10 per cent by weight.
DEFINITIONS :
(1)
“Foreign
matter means any extraneous matter than other food grains comprising of;
(a)
“Inorganic matter” includes metallic pieces, dust,
sand, gravel, stones, dirt, pebbles, lumps of earth, clay and mud and animal filth etc;
(b)
“Organic matter” consisting of husk, straws, weeds and
other inedible grains etc.;
(2)
“Other Edible
grains” means any edible grains (including oil seeds) other than the one which
is under consideration;
(3)
“Damaged
grains” means grains that are sprouted or internally damaged as a result of
heat, microbe, moisture or weather viz., ergot affected grains and kernel bunt
grains;
(4)
“Immature
and shrivelled grains” means grains that
are not properly developed;
(5)
“Weevilled
grains” means grains that are partially or wholly bored by insects injurious to
grains but does not include germ eaten grains and egg spotted grains;
(6)
“Poisonous,
toxic and/or harmful seeds” means any seeds which if present in quantities
above permissible limit may have damaging or dangerous effect on health,
organoleptic properties or technological performance such as dhatura (D. fastuosa linn and D.stramonium linn.) corn cokle (Agrostemma githago L.Machai Lallium
remulenum linn.) Akra (vicia
species).
as prescribed in Prevention of Food
Adulteration Rules, 1955.
8. STANDARDS APPLICABLE
FOR INTERNTIONAL TRADE.
8.1 CODEX ALIMENTARIUS
COMMISSION (CAC)
Codex Alimentarius Commission (CAC)
implements joint FAO/WHO Food Standards Programme. The purpose of the CAC programme is to
protect the health of consumers and ensure fair practices in the food
trade. The CAC is a collection of
internationally adopted food standards presented in a uniform manner. Sanitary and Phyto-Sanitary Agreement and
Technical Barriers to Trade Agreement of World Trade Organisation recognizes
standards framed by CAC with respect to safety and quality aspects of food
items. Thus for international trade
standards framed by CAC are recognized.
8.1.1
Codex Standard For Maize (Corn)
SCOPE
This standard applies to Maize (corn) for human
consumption, i.e. ready for its intended use as human food, presented in
packaged form or sold loose from the package directly to the consumer. This standard specifies requirements for
whole grain shelled dent maize, Zea mays
indentata L., and/or shelled flint maize, Zea mays indurata L., or their hybrids. It does not apply to processed Maize.
Product Definition:
Maize (corn) is the shelled grains of the
species defined in the Scope.
Quality factors – General
Maize shall be safe and
suitable for human consumption.
Maize shall be free from
abnormal flavours, odours and living insects.
Quality
factors - Specific
|
Parameter |
Maize(corn) |
|
Moisture
content, Max. |
15.5%
m/m |
|
Organic
extraneous matter, Max. |
1.5%
m/m |
|
Inorganic
extraneous matter, Max. |
0.5%
m/m |
|
Filth
(impurities of animal origin, including dead insects) Max. |
0.1%m/m |
|
KERNELS OF OTHER COLOURS
·
In yellow maize.
Maize grains which are yellow and/or light red in colour are
considered to be yellow maize. Maize
grains which are yellow and dark red
in colour, provided the dark red colour covers less than 50% of the surface of the grain,
are also considered to be yellow maize.
·
In white maize.
Maize grains which are white and/or light pink in colour are considered
to be white maize. White maize also
means maize grains which are white and pink in colour, provided the pink
colour covers less than 50% of the surface of the grain.
·
In red maize. Maize
grains which are pink and white or dark red and yellow in colour are
considered to be red maize, provided the pink or dark red colour covers 50%
or more of the surface of the grain.
·
Mixed maize KERNELS OF
OTHER SHAPE
·
In flint maize
·
In dent maize
·
|
MAX:
5.0% by weight of maize of other colours MAX:
2.0% by weight of maize of other colours. MAX:
5.0% by weight of maize of other colours. MAX:
5.0% by weight of maize of other shapes. MAX:5.0%
by weight of maize of other shapes. RANGE:
5.0% to 95% by weight of flint maize. |
|
DEFECTS
·
Blemished grains: (grains which are insect or vermin damaged, stained diseased ,discoloured ,germinated frost
damaged or otherwise materially damaged) ,Max.
·
Broken kernels, Max.
·
Other grains, Max. |
7.0
% of which diseased grains must not exceed 0.5%. 6.0%
2.0% |
Toxic
or Noxious Seeds
The maize(corn) shall be
free from the following toxic or noxious seeds in amounts which may represent a
hazard to human health.
Crotolaria (Crotalaria spp.), Corn cockle (Agrostemma githago L.) Castor bean (Ricinus
communis L.), Jimson weed (Datura
spp.) and other seeds that are commonly recognized as harmful to health.
HYGIENE
The maize(corn):
·
Shall be free from microorganisms in amounts which
may represent a hazard to health.
·
Shall be free from parasites which may represent a
hazard to health.
·
Shall not contain any substance originating from
microorganisms, including fungi, in amounts which may represent a hazard to
health.
Heavy
Metals
Maximum
level of Lead 0.2 Mg/Kg
Maximum
level of Cadmium 0.1
Mg/Kg
Pesticide Residues:
The maize(corn) shall
comply with following maximum pesticide
residue limits.
|
Sl.No. |
PESTICIDE |
MRL (mg/kg) |
|
1 |
2,4-D |
0.05 |
|
2 |
ALDICARB |
0.05 |
|
3. |
BENTAZONE |
0.2 |
|
4 |
BIFENTHRIN |
0.05 |
|
5. |
CARBARYL |
0.02 |
|
6. |
CARBOFURAN |
0.05 |
|
7. |
CARBOSULFAN |
0.05 |
|
8. |
CHLORDANE |
0.02 |
|
9. |
CHLORPYRIFOS |
0.05 |
|
10. |
CYFLUTHRIN |
0.05 |
|
11. |
CYPERMETHRIN |
0.05 |
|
12. |
DIAZINON |
0.02 |
|
13. |
DIQUAT |
0.05 |
|
14. |
DISULFOTON |
0.02 |
|
15. |
ENDOSULFAN |
0.01 |
|
16 |
ETHOPROPHOS |
0.02 |
|
17. |
FIPRONIL |
0.01 |
|
18. |
GLUFOSINATE-AMMONIUM |
0.1 |
|
19. |
GLYPHOSATE |
1 |
|
20. |
LINDANE |
0.01 |
|
21. |
METHIDATHION |
0.1 |
|
22. |
METHOMYL |
0.02 |
|
23 |
METHOXYFENOZIDE |
0.02 |
|
24. |
PARAQUAT |
0.1 |
|
25. |
PHORATE |
0.05 |
|
26. |
PROPARGITE |
0.1 |
|
27. |
QUINTOZENE |
0.01 |
|
28. |
TERBUFOS |
0.01 |