Table 4.0.1. Possible losses of rice, theoretical estimated percentages.
|
Paddy (%) |
Milled rice (%) | |||||
|
Harvesting |
Transport to |
Storage at |
Processing at |
Transport to |
Retail | |
|
Reaping |
Threshing |
mills |
mills |
mills |
storage |
Storage |
|
2-3.5 |
1.5-2.0 |
0.5-1 |
0.5-1.5 |
0.2-0.5 |
ca. 0.5 |
0.5-1.5 |
Overall average losses: about 6-10%.
Note: Bird losses before reaping can be up to 20% by weight.
Table 4.0.2. Quantitative loss ranges of grain postharvest system for three seasons, Zeijiang, China, 1987-1989.
|
Postharvest operation and method |
Loss range, % |
Average share of | |||
|
Min |
Max |
% |
Total loss, % | ||
Harvesting |
0.29 |
2.34 |
0.85 |
5.81 | |
By sickle |
0.29 |
0.58 |
0.43 |
||
Combine harvester-thresher |
2.73 |
4.29 |
3.38 |
||
|
Threshing |
0.62 |
2.68 |
1.31 |
8.85 | |
By pedal thresher |
0.62 |
1.08 |
0.80 |
||
By motor thresher |
0.92 |
2.68 |
1.52 |
||
|
Drying and cleaning |
1.72 |
7.36 |
3.47 |
23.43 | |
Sun dried on bamboo mat, re-threshed by hand and use of
|
2.59 |
4.32 |
3.35 |
||
Sun dried on cement yard, bamboo sieve plus electric blower |
2.61 |
5.61 |
4.10 |
||
Sun dried on cement yard,, mechanical vibrating screen with
|
2.58 |
3.05 |
2.90 |
||
|
Storage |
2.89 |
8.124 |
5.46 |
36.87 | |
Moulds |
1.27 |
2.02 |
1.59 |
||
Insects |
0.43 |
2.18 |
1.15 |
||
Rats |
1.00 |
3.98 |
2.72 |
||
|
Transportation |
0.59 |
1.11 |
0.97 |
6.55 | |
|
Milling |
1.95 |
4.39 |
2.74 |
18.5 | |
|
Total |
8.02 |
26.02 |
14.81 |
100.01 | |
Source: Ren-Yong et al., 1990.
Table 4.0.3. Typical values of quantitative postharvest grain losses in Indonesia.
|
Operation |
Loss, % |
|
Harvesting |
0.89 |
|
Threshing |
0.99 |
|
Drying |
3.16 |
|
Storage |
3.74 |
|
Milling |
4.78 |
|
13.56 |
Source: FAO, 1981.
Table 4.0.4. Average physical losses among alternative postharvest systems in two regions, Philippines, 1975-1977.
|
Operation |
Manual, % |
Mechanical, % |
Difference, % |
|
Threshing |
|||
Central Luzon (threshing frame vs axial-flow) |
2.4 |
1.1 |
1.3 |
Bicol (flailstick vs axial-flow) |
1.2 |
0.5 |
0.7 |
(threshing frame vs axial-flow) |
1.6 |
0.5 |
1.1 |
|
Cleaning |
|||
Central Luzon (winnowing basket) |
1.1 |
a |
1.1 |
Bicol (wooden winnower) |
1.1 |
a |
1.1 |
|
|||
Central Luzon |
1.2 |
0.1 |
1.1 |
Bicol |
1.2 |
0.4 |
0.8 |
a With mechanical threshing using the axial-flow thresher, the threshing and cleaning operation s accomplished simultaneously during threshing.
Source: Toquero and Duff, 1985.
Table 4.0.5. Losses of rice within the postharvest system.
|
Region and
|
Total weight loss
|
Remarks |
|
WEST AFRICA |
6 - 24 |
Drying 1-2; on-farm storage 2-10; parboiling 1-2; milling 2-10 |
Sierra Leone |
10 |
|
Uganda |
11 |
|
Rwanda |
9 |
|
Sudan |
17 |
Central storage |
Egypt |
2.5 |
|
|
ASIA |
||
Bangladesh |
7 |
|
India |
6
|
Unspecified storage
|
Indonesia |
6 - 17 |
Drying 2; storage 2-5 |
Malaysia |
17 - 25
|
Central storage 6; threshing 5-13;
|
Nepal |
4 - 22 |
On-farm 3-4; on-farm storage 15;
|
Pakistan |
7
|
Unspecified storage 5
|
Philippines |
9 - 34 up to 30
|
Drying 1-5; unspecified storage 2-6; threshing 2-6
|
Sri Lanka |
13 - 40
|
Drying 1-5; central storage 6.5; threshing 2-6
|
Thailand |
8-14
|
On-farm storage 1.5-3.5; central storage 1.5-3.5
|
|
LATIN AMERICA |
||
Belize |
20-30 |
On-farm storage |
Bolivia |
16 |
On-farm 2; drying 5; unspecified storage 7 |
Brazil |
1-30 |
Unspecified storage 1-30 |
Dominican Republic |
6.5 |
On-farm storage 3; central storage 0.3 |
Source: FAO
Table 4.0.6. Losses in drying and storage.
|
Method
|
Range of losses, % |
Average losses, % |
|
Harvesting |
0.29-2.34 |
0.86 |
|
Sickle |
0.29-0.53 |
0.43 |
|
Combine |
1.54-2.34 |
1.82 |
|
Threshing |
0.2-2.68 |
1.31 |
|
Pedal thresher |
0.62-1.03 |
0.80 |
|
Motor thresher |
0.90-2.68 |
1.52 |
|
Cleaning and drying |
3.47 | |
|
2.59-4.32 |
3.35 |
|
2.61-5.16 |
4.10 |
|
2.58-3.05 |
2.90 |
|
Storing |
5.23 | |
|
1.9-3.88 |
2.89 |
|
3.17-5.17 |
4.67 |
|
6.04-10.24 |
8.14 |
Source: Yong et al., 1997.
Table 4.0.7. Estimated losses in caloric value, protein and thiamin in rice samples infested by Sitophilus oryzae.
Losses per kg of Grain* | ||||||
Infestation period
|
Infested Grains % |
Weight Loss
|
Caloric Value |
Protein,
|
Thiamine
| |
Raw milled rice |
||||||
2 |
1.1 |
0.2 |
7 |
0.15 |
0.05 | |
4 |
7.9 |
1.65 |
58 |
1.2 |
0.03 | |
6 |
11.0 |
2.9 |
103 |
2.2 |
0.03 | |
8 |
13.5 |
4.7 |
163 |
3.5 |
0.03 | |
Raw handed-pounded rice |
||||||
2 |
8.7 |
0.3 |
11 |
0.2 |
0.04 | |
4 |
26.1 |
2.5 |
86 |
1.9 |
0.12 | |
6 |
42.5 |
6.1 |
213 |
4.6 |
0.18 | |
8 |
49.6 |
14.2 |
497 |
10.6 |
0.26 | |
Raw husked rice |
||||||
2 |
6.6 |
1.1 |
38 |
0.8 |
0.14 | |
4 |
19.0 |
6.9 |
243 |
5.2 |
0.22 | |
6 |
31.5 |
16.0 |
561 |
12.0 |
0.29 | |
8 |
39.0 |
22.8 |
800 |
17.1 |
0.36 | |
Parboiled milled rice |
||||||
2 |
0.6 |
0.1 |
4 |
0.1 |
0.03 | |
4 |
2.5 |
1.0 |
36 |
0.8 |
0.06 | |
6 |
6.9 |
3.0 |
106 |
2.3 |
0.12 | |
8 |
12.7 |
4.6 |
160 |
3.4 |
0.11 | |
Source: Pingali et al. 1957.
Table 4.0.8. Estimated losses of paddy and rice at each stage of production and processing (a suggested format)
Region/Country |
Stage of production and post production/ Source of losses |
Grain loss, % of yield |
Sources |
Pre-harvest - field shattering at maturity
|
|||
Low-shattering variety |
|||
Medium-shattering variety |
|||
High-shattering variety |
|||
as attacked by birds and rodents |
|||
Harvesting |
|||
Traditional manual gathering of panicles
|
|||
_________________________________________________________________
Stage of production and post production/ Grain loss, Source
Source of losses % of yield
_________________________________________________________________
Pre-harvest - field shattering at maturity
due to wind, rain and natural dehiscence
as influenced by varietal characteristics
Low-shattering variety
Medium-shattering variety
Medium-shattering variety
as attacked by birds and rodents
________________________________________________________________
Harvesting
Traditional manual gathering of panicles
of low-shattering variety
Traditional cutting of stalks, piling in
small bundles and stacking
Traditional cutting of stalks and windrowing
or laying to field dry
Two-wheeled tractor-mounted reaper
Sri Lanka
Four-wheeled tractor-mounted reaper
Pakistan
Self-propelled reaper binder
Self-propelled stripper gatherer
Rice combine
Thailand
Malaysia
Japan, Rep. of Korea, Taiwan prov. of China
USA
Italy
Spain
Africa
Latin America
____________________________________________________________
Threshing
Human treading, manual winnowing and bagging
Animal treading, manual winnowing and bagging
Four-wheeled tractor treading, manual winnowing
and bagging
Throw-in type, engine-powered portable thresher
and bagging
Philippines, Indonesia (1-2 t/h capacity)
Thailand (2-3 t/h capacity)
Vietnam (2 t/h capacity)
Hold-on type thresher and bagging
Pedal-powered (Philippines, some areas)
Engine-powered (Japan and Rep. of Korea)
___________________________________________________________
Handling and transporting
Traditional cut stalk, windrow or lay on field
to dry, bundle and carry on back
Preparation of bundle and loading
Carrying on back, loss on trails
Carrying on back, loss on resting points
Traditional cut panicle, bundle and carry on head
by women; low shattering variety
Traditional cut panicle, bundle, balance bundles at ends
of pole and carry on shoulder by men
Bagging paddy output from threshing and cleaning
From pedal thresher
From mat after beating paddy against wood block,
rock or bamboo slats or beating paddy with
stick or flail
From hold-on type thresher (engine-powered)
From throw-in type thresher (engine-powered)
From small combine (Japan, Rep. of Korea)
From stripper harvester-gatherer and re-thresher
Bulk transfer from combine to lorry or wagon and
transport to drying compound or rice mill
____________________________________________________________