Sunflower and Oilseed Storage

Stored Products Research and Education CenterOklahoma State University

Carol JonesBiosystems and Agricultural Engineering

Storage Concerns

• Sunflower• Canola• Soybean• Sesame• Safflower

Storage Concerns• Moisture Content

– Sunflower: 8 – 10% mc• Hulls dry faster than kernels• Overnight in a sealed jar

– Canola: 10 – 12% mc– Soybeans: 12%...seed at 10%– Sesame: less than 6%– Safflower: 5 – 8%

Storage Concerns

Why so dry????????Rancidity in Oklahoma heatOil content = microbial activityOil content = heatSweat period

Storage ConcernsSunflower:

hulls have hair-like fibersfibers can cause increase fire dangertest weight 28 – 32 lb/bu...cover when haulinglow speed augers to prevent damage

Storage ConcernsCanola:• seed is VERY small, hard to handle• sweat period is about 6 weeks• test weight 52 lbs/bu• oil content 40 – 50%• begin aeration immediately

Storage Concerns

Soybeans:• using a dryer? Keep air above 40% rh

and around 85 degrees F....• maybe ambient will work• run augers as full and slow as

possible• test weight 60 lbs/bu• aerate once a month after initial

cooling

Storage Concerns

Sesame:• Much like handling canola except...• Planted in spring, harvested in fall• Takes longer to dry in windrow than canola• Fewer inputs than canola• High fat (50% oil), 25% protein, 43 – 47 lb/bu• Small flat seed• Goes rancid quickly in heat at MC > 6%

Storage ConcernsSafflower:• 38 lb/bu test weight• 34 – 36% oil content• Seeds are white• Harvested and handled much like canola• Dries very quickly in windrows

Special Characteristics

• Bins with perforated floors work best• Ambient air/fan sufficient for drying/cooling• No aeration??? Move between bins

Prepare Bins for Storage

• Floor perforations must be protected– Line bottom of bins

• two layers of aluminum window screen• trampoline tarpaulin

• Leave opening for grain unloading

Store Clean Canola

• Debris can add moisture and attract insects

• Clean using– scalper aspiration– indent cylinder cleaning– sieve screening

• Clean to less than 2.3% foreign material

Temperature and Moisture

• Optimum temperature is 55°F• Double storage time for every 10° below 77°

and 1% reduction in moisture below 9%

6

7

8

9

10

11

12

13

0 20 40 60 80 100

Temperature, deg. F at Binning

% M

oist

ure

at B

inni

ng

Spoilage after 5 months

No spoilage for at least 5 months

Optimum storage

Temperature

• Above 77°F– Free fatty acids may form when

stored longer than a year (1-1.5% limit) and causes rancidity

– peroxide levels increase– oil darkens– Insect activity increases

Molds• Mold forms above 60% equilibrium relative

humidity (ERH)

ERH %

(40% seed oil content)

Temperature °F

20 30 40 50 60 70 80

20 4.9 4.5 4.1 3.8 3.6 3.4 3.2

30 6.5 5.9 5.5 5.1 4.8 4.5 4.3

40 8.1 7.4 6.8 6.3 6.0 5.6 5.3

50 9.6 8.8 8.1 7.6 7.1 6.8 6.4

60 11.3 10.3 9.6 9.0 8.4 8.0 7.6

70 13.1 12.1 11.2 10.5 10.0 9.3 8.9

80 15.4 14.2 13.2 12.3 11.6 11.0 10.5

90 18.6 17.2 16.0 15.0 14.2 13.5 12.8

ERH and temperature influence on seed moisture content (NDSU 2005)

Shaded area shows moisture content for optimum conditions

Aeration• Bin must have aeration system• Full floor perforation is best• Positive pressure is preferred• Grain surface should be leveled• Airflow rates for temperature management

– 0.08 – 0.15 cfm/bu– At 0.08 cfm, up to 150-200 hours for a 20° drop

• Airflow rates for natural air drying– 0.4 – 2.0 cfm/bu – increase static air pressure– run fans continuously until desired moisture

Aeration• Static pressure

– Sunflower• 30 Ft. deep at 1.0 cfm/bu...15.1 inches

– for canola is 2-3 times that of wheat• 30 ft. deep at 1.0 cfm/bu...75 inches!!!!• 10 ft. deep at 1.0 cfm/bu...7 inches

– Soybeans• 30 ft. deep at 1.0 cfm/bu...7.7 inches

– Sesame• Similar to canola

– Safflower• “Less than most other grains”

KEY THOUGHTS...• Monitor bins closely...weekly

• Temp control + MC control + insect control

= SUCCESSFUL

OILSEED STORAGE

Insect Pests Found in Bins

• Very few insects were found• Those found included:

– Rusty grain beetle– Red flour beetle– Lesser grain borer– Indianmeal moth– Booklice

• Predatory mites were

also found

Oilseeds..the market

• Another option• Rotation• Biodiesel• Crusher in OKC

Questions?

BIOSYSTEMS.OKSTATE.EDU/HOME/JCAROL