Manual on Simple Paddy Quality Checking

in the Fields/Storages of Farmers/Traders

March 2016

Federal Ministry of Agriculture and Rural Development (FMARD)

Japan Interna�onal Coopera�on Agency (JICA)

Table of Contents

1. Importance of Simple Paddy Quality Checking in the Fields/Storages of

Farmers/Traders … ……………………………………………………………………………………………11

2. Sample Photos………………………………………………………………………………………………….2

3. Procedure of Paddy Grading……………………………………………………………………………..8

Reference – Dra� paddy (Rough) Rice – Specificaa�ony SON………………………….15

4. List of Equipment…………………………………………………………………………………………….16

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1. Importance of Simple Paddy Quality Checking in the Fields/Storages of Farmers/Traders

For Farmers/Paddy Traders · Paddy grading can be conducted only in the grading laboratories of mills with a

set of equipment.

· Since the grade affects the procurement price of paddy, farmers want to

the grade before paddy sales.

· With the simple paddy quality checking methods in this manual, farmers can

the grade of their paddy with a set of less expensive equipment, so

that they can verify the grade prescribed by mills.

· Farmers can also conduct the simple checking for finding out what they have

to do, in order to improve their cul�va�on and /or post-harvest ac�vi�es.

For Traders · Traders can conduct the simple checking for their decision making on

procurement and sale of paddy.

For Mills · The procurement officers of mills can conduct simple checking for decision

making on procurement in the fields.

· Mills that do not have grading laboratories, for a while, can check the quality

with methods in this manual.

Limita�on of methods in this manual

Through the methods in this manual, percentages of some characteris�cs (pest

damaged and discolored grains) in page 15 can be given only up to 1 % while grading

requires concluding the percentage by 0.5 %. Therefore, methods in this manual

cannot be used to grade paddy but can be used only to es�mate the grade. For

grading, use methods in Paddy Grading Manual.

1

2. Sample Photos Empty shell and sound grains

Empty Shells Sound Grain

2

Discolored 1

Sound Grain

Discolored Grain 1

4

3

Discolored 2

Sound Grain

Discolored Grain 2

5

4

Damaged

Sound Grain

Damaged Grain

6

5

Pinpoint Damaged

Sound Grain

Pinpoint Damaged Grain

7

6

Red*

Sound Grain

Red Grain

*Note: Red rice is not included in SON characteris�cs

8

7

Paddy

A. Sampling

Paddy Sample (23 g)

B. Moisture contents (I)

Paddy sample (Minimum 20 g) (II)

C. Sieving

Complete Paddy Inorganic foreign maters ( FMs)

Empty (thinner) shells/Organic FMs

D. Manual separa�on

Complete Paddy Inorganic FMs

Organic FMs

E. Aggrega�on of FMs

Inorganic FMs (IV)

Organic FMs (III)

F. Husking

Husked grain (10 - 11 g) (V) Husk

G. Sieving

Complete Grain Immature/Shrivelled grain (VI)

H. Separa�on

Complete grain Broken grain

I. Grain coun�ng

Complete grain (100 grains) (VII)

Back up

Count good, pest damaged (VIII), discolored (IX) and red grains

3g

3. Procedure of Paddy Grading - Work Flow

8

Methods in Each Step A. Sampling

• Take samples from selected paddy in the fields/bags in the storages.

• From the sample, take 3 g for checking moisture contents, and 20 g (II in the work flow) for other checks. (Total 23 g)

Number of bags and amount to be sampled

Remark: If inconsistency among the bags is found, all the bags should be checked.

Number of bags received Number of bags to be checked

2 ~ 15 all

15 ~ 25 13

26 ~ 50 15

51 ~ 100 18

101 ~ 200 20

201 ~ 1,000 32

1,001 ~ 3,000 50

3,001 ~ 10,000 80

10,001 ~ 35,000 125

35,001 ~ 200

B. Moisture content (MC) check

• Although farmers /traders usually es�mate the MC of paddy through bi�ng, a group should possess a handy moisture meter and use it some�mes. (Use the moisture meters made by reputable manufacturers.)

• Follow the instruc�ons of the moisture meter.

9

C. Sieving paddy

• Sieve the paddy sample in 30 seconds with the sieve having 1.7 mm holes. Grains and others which pass through the holes can be regarded as empty (thinner) shells and foreign ma�ers (FMs).

• Separate those into organic and inorganic.

D. Manual separa�on of FMs

• Since sieved grains s�ll include FMs, manually separate these (organic and inorganic separately) from sound grains.

10

E. Aggrega�on of FMs

• Combine organic FMs from (Ac�vity C.) and (D.) into one.

• Also, combine inorganic FMs from (C.) and (D.) into one.

• Weigh organic (III) and inorganic (IV) respec�vely.

F. Husking

• Husk all sieved grains. (If you do not need to conduct (H.), 5 g is enough.)

• With a test husker, husk sample paddy.

• A�er husking, weigh husked brown rice (V).

11

G. Sieving for separa�on of immature / shrivelled grains - 1

• Sieve brown rice in 30 seconds with the sieve having 1.6 mm holes. The rice which passes through the holes include immature /shrivelled grains, and broken grains.

G. Sieving for separa�on of immature/shrivelled grains - 2

• Separate immature/ shrivelled grains and bigger broken grains (bigger than half of whole grains).

• Weigh separated immature/shrivelled grains (VI).

Immature grains

others

12

H. Separa�on of broken rice

• Brown rice which did not pass the sieve in (G.) includes some broken grains. For proper coun�ng of problema�c grains in (I.), manually separate broken grains.

• If you can see more than 200 whole grains in the sample, before separa�on, divide the sample into two.

whole grain

broken

I. Coun�ng the number of grains with problems

• Put the brown rice grains on the pan, and remove grains, which are not in the concaves, from the pan. Since the pan has 100 concaves, you can get % of each problema�c grain types through coun�ng them.

13

Proper threshing and winnowing

• Proper threshing and winnowing are cri�cal in obtaining be�er quality paddy.

Manual Winnowing Manual Threshing

14

Reference: Draft Paddy (Rough) Rice – Specification by SON

Table 1 — Specific requirements

S/No

Characteristics

Grade 1

Grade 2

Grade 3

Test Method

1 Purity, %m/m (weight basis.) mim (100 %– (2+3+4+6))

Minimum Limits ISO 605

98

95

95

Maximum Limits 2 Foreign

matter, % m/m

Organic (empty shell + other organic.) [(III/II) x 100 %]

1.0

1.5

2.0

Inorganic [(IV/II) x 100 %]

0.25

0.25

0.5

3 Pest damaged grains, % m/m, max [(VIII/VII) x 100 %]

0.5

0.75

1.0

4 Discoloured grains, % m/m, max [(IX/VII) x 100 %]

0.5

2.0

4.0

5 Moisture, % m/m, max [ I ]

14.0 14.0 14.0 ISO 711; ISO 712

6 Immature/shrivelled grains, % m/m (thinner grain (less than 1.6 mm)) [(VI/V) x 100 %]

1.0

3.0

5.0

ISO 605

Paddy can be categorized into wholly long, medium and short grain.

Notes with Italic and Underline were made by FMARD/JICA

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