Rice Storage Systems Joe Rickman and Martin Gummert, Agricultural Engineering, International Rice Research Institute, Philippines

Outline of today Discussion on storage Fill hermetic storage system Evaluate a seed store Determine density of different products Make small seed store Take grain samples and analysis for insects Discuss pest management in storage Set up some seed germination tests Seal grain ready for fumigation

(Total world cereal and pulse production 2,075 million tons) Rice production World – 589 million tons Asia - 534 million tons Bag storage - 500 million tons (Total world cereal and pulse production 2,075 million tons)

Present situation Between 25-50% of the total grain value (quantity+quality)is lost between harvest and consumption in developing countries

Quantity Losses in Cambodia (88 on farm studies) Post-harvest stage Mean (%) Range Cutting 3.0 2.2 – 3.8 Transportation 3.6 2.0 – 5.2 Threshing 1.6 1.0 – 2.2 Drying 2.0 1.0 – 2.0 Storage 10.7 3.5 – 18.0 Milling 14.7 7.5 – 22.0 TOTAL 35.6 17.2 - 53.2

Reasons for post harvest losses Poor product coming into storage Poor storage management Poor quality paddy + poor milling techniques

What is required of a good storage system Prevention of moisture re-entering the grain after drying Protection from insects, rodents and birds Ease of loading and unloading. Efficient use of space Ease of maintenance and management.

Present on farm storage situation in Asia

Traditional Bag Storage (Indonesia)

Granary (Laos)

Woven Basket ( Cambodia)

Clay Pots (Bangladesh)

Concrete Bin (Bhutan)

Steel Bins (Bhutan)

Bag storage (Philippines)

Equilibrium Moisture Content (Philippines) 12.5 13 13.5 14 14.5 15 15.5 16 16.5 17 January February March April May June July August September October November December Months Equilibrium Moisture Content (%)

Summarizing existing on farm storage situation Grain is stored in open systems in bags or open granaries Grain is exposed to insect,rodent and bird attacks High equilibrium moisture content >14.0 Grain is not always protected from rain

Farmers Present Practices Sell excess immediately after harvest (indebted or poor storage) Dry grain to 10-11% before storage Take grain out and re-dry during storage period Store seed in “sealed” containers

Present commercial storage situation in Asia

Commercial bag storage system Open to atmosphere moisture uptake, pest problems Store in batches Clear headways and walkways Relatively easy to fumigate

Commercial Bulk Storage Not popular in Asia Efficient use of space Easy to control pests?- sealed for fumigation Less problems with rodents and birds

Commercial hermetic system Grain stored in bags Protected against moisture uptake and insects Rat and pig damage? Use as harvest management aid Need O2 monitoring Big potential in Tropical areas 5-300 metric tons

Sealed Systems tested by IRRI

Parameters evaluated In store atmosphere (02) Grain moisture content Seed germination Insects Grain quality Farmer uptake

Storage atmosphere (0xygen level) 2 4 6 8 10 12 14 16 18 20 22 40 60 80 100 Claypot 200 l drum 25 l O2 (%) Days

Storage atmosphere after opening 6 12 18 24 30 60 90 120 150 180 210 240 270 Storage time (days) Oxygen concentration (%)

Storage atmosphere Plastic pouches (3kg) 5 10 15 20 25 30 40 50 60 70 80 Days Oxygen Content (%) Normal plastic Vacuum pouch

Moisture levels in stored grain 9 10 11 12 13 14 15 20 30 40 50 Storage period (weeks) % Moisture content control Hermetic cooled

Live Insect Counts (Insects/ kg) Months Open Storage (bags) Hermetic (5 ton) Hermetic (small) Cold room Air conditioner 3.2 8.8 7.4 8.4 3 234 1.4 1.6 6 114 0.4 3.0 9 54.4 1.2 3.4 12 27.2 2.2 9.0 8.4

Germination: certified seed

On farm Storage Bangladesh (7 months) 20 40 60 80 100 Farmer 1 2 3 4 5 Traditional Hermetic Germination (%)

Head Rice Yields (whole kernel) 20 25 30 35 40 45 3 6 9 12 Months of storage Head rice yield (%) Hermetic Open Storage

Grain Whiteness Index 40 42 44 46 48 50 52 54 Open Hermetic A/C Cold Room Storage treatment Whiteness index Start 3 months 6 months 15 months 18 months

Summary of results Hermetic storage: Works for 3kg “plastic bags” – 50ton Cubes Reduces insects activity (1/kg) Constant grain moisture content Increases the life of seed from 6 months to 12 months Maintains milling quality, Protects grain from birds and rodents? NEXT STEP

Adoption by farmers Problem Farmers will not share a larger storage system Farmers will not invest in large storage systems Needs to fit into existing system

Solution- Turn 50kg bag into a hermetic system

Characteristics needed of a storage bag Capacity 0.08 cubic meter (50kg) Low O2 permeability Low water vapor permeability High puncture strength High tensile strength Cost $ US 1/bag

“Plastic” Liner bag Fits into existing system Reusable if not punctured Easily sealed Use for all grain crops Reasonable cost

Storage at IRRI Seed Air conditioned room Grain Hermetic storage (longer than 1 month) Open pallets (less than 1 month) 50kg woven plastic bags

Storage Hygiene Keep storage areas clean. Clean storage rooms after they are emptied Placing rat-traps and barriers in drying and storage areas. Cats deter and help control rats and mice Inspect storage room regularly to keep it vermin proof. Inspect the stored seeds once a week for signs of insect infestation.

The End

PPTW - Storage activities Determine density of paddy, husk, milled rice, bran Evaluate seed storage systems at IRRI Load and sealing 5 t hermetic storage system (2 groups) Make small seed storage system (1 per group) Sample seed store and set up germination test Sample stored grain and identify insects Seal grain storage system ready for fumigation

Evaluating a seed store Evaluating Storage Facilities   Evaluating a seed store   Store 1 Store 2 Store 3 Grain Protection Moisture content Insects Rodents Birds In store Hygiene Storage above floor (pallets) Clearways (0.5m) Batch storing Clean Management strategies Store cleaning after season Bags cleaned, dipped Fumigation options