Know Your Commodity REFERENCES — Onions (Dry)

Know Your Commodity References — Onions (Dry) Page 1 of 6 Copyright © Blue Book Services 1992, 2012, 2015

Know Your Commodity REFERENCES — Onions (Dry)

Know Your Commodity References — Onions (Dry) Page 2 of 6 Copyright © Blue Book Services 1992, 2012, 2015

Know Your Commodity REFERENCES

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Onions (Dry)

There is no conclusive evidence as to the exact location and time the onion was discovered but many archaeologists, botanists, and food historians believe it originated in central Asia. Onions may have been the earliest cultivated crop; they were easy to grow, transportable, and less perishable than other foods of the time. As a cool-season vegetable, onions can be grown successfully throughout most of temperate North America. Onions contain sulphuric compounds that make your eyes water, but if you chill for thirty minutes then cut off the top and peel the outer layers leaving the root end intact, you can reduce tearing. The root end has the highest concentration of sulphuric compounds. Sources: National Onion Association, University of Illinois Extension.

TYPES, VARIETIES & CUTS Dry onions refer to large, bulbous onions with a shiny outer layer of skin and are sold in stores as yellow, red, or white. Short day varieties (Bermuda/Grano/Granex) are typically grown in southern states where temperatures are normally warmer year round. These onions have a higher concentration of water as opposed to solid fiber content, so they do not store well and should be eaten fresh. Long day varieties grow better in northern states, generally have a more pungent flavor, and store better than short day onions. The exception to this rule is Walla Walla onions; they are a sweet, long day yellow onion that does not store as well as other long day varieties. Sources: National Onion Association, Texas AgriLife Extension Service, Texas A&M System. Know Your Commodity References — Onions (Dry) Page 3 of 6 Copyright © Blue Book Services 1992, 2012, 2015

Know Your Commodity REFERENCES — Onions (Dry) SEASONAL AVAILABILITY - DOMESTIC ARIZONA CALIFORNIA COLORADO GEORGIA HAWAII IDAHO ILLINOIS INDIANA IOWA MICHIGAN MINNESOTA NEVADA NEW MEXICO NEW YORK NORTH DAKOTA OHIO OREGON TEXAS UTAH WASHINGTON WISCONSIN

SEASONAL AVAILABILITY - INTERNATIONAL ARGENTINA BOLIVIA CANADA CHILE CHINA COLOMBIA ECUADOR FRANCE GUATEMALA HONDURAS ITALY MEXICO NETHERLANDS NEW ZEALAND NICARAGUA PERU POLAND Know Your Commodity References — Onions (Dry) Page 4 of 6 Copyright © Blue Book Services 1992, 2012, 2015

Know Your Commodity REFERENCES — Onions (Dry) PESTS & DISEASE Common diseases: Botrytis neck rot is a watery-decay that initiates at the neck area and moves downward through the entire bulb. Gray fungal growth is visible at neck and outer scales. Black mold is often associated with bruising and characterized by black discoloration and shriveling at neck and outer scales. Black mold will lead to bacterial soft rot, characterized as a watery, fowl-smelling viscous liquidy rot. Harvesting at full maturity, proper drying and curing, minimal bruising and scraping, and maintaining proper storage conditions to prevent condensation will generally control these bacterial rots. Common pests: The onion fly looks similar to a small house fly and lays its eggs in seedlings or soil at the base of plants. The maggots cause the onion leaves to go pale, wilt, and die off; the inside of the bulb becomes rotten causing the plant to die. Lesser bulb fly is a similar, but smaller fly. The lesser bulb fly also works in patches so they are easy to spot. An infected plant has to be completely removed before maggots burrow back into the soil. Thrips cut the epidermis of the leaves or stems and eat the plant sap. They leave white silvery blotches on deformed leaves, are female, and can reproduce without a male. Sources: UC Davis Postharvest website, Clemson University Cooperative Extension Service.

CULTIVATION, STORAGE & PACKAGING Preharvest Climates with high temperatures and low humidity are advantageous. Plants should be spaced four to five inches apart to produce large-sized bulbs, as closer spacing significantly decreases bulb size. Onions have shallow roots and compete poorly with weeds and grasses. Timely weeding and hoeing is recommended during the growing season. Postharvest Onions are harvested in late July, early August when most of the tops have fallen over. To prevent damage and bruising, specially manufactured harvesters gently lift onions from the bed and either deliver them into long rows to dry in the field (weather permitting), or to a trailer for off-site drying. Optimum temperature for field curing is 75ºF (24ºC) with 75 to 80% relative humidity. Mild onions will store for up to 1 month at 32ºF (0ºC) while pungent onions will store for up to 6 to 9 months at 32ºF (0ºC). Optimum relative humidity in storage is 65 to 70% with adequate air circulation. Sources: University of Illinois Extension, UC Davis Postharvest website.

GOOD ARRIVAL GUIDELINES/TOLERANCES Good Arrival Guidelines in the United States for Bermuda/Grano/Granex onions permit 15% total average defects and 4% decay upon arrival at contract destination after five days in transit. Guidelines for other onions permit 8% total average defects and 4% decay upon arrival at contract destination after five days in transit. Good Arrival Guidelines in Canada permit 10% total defects allowed by grade, 5% total permanent defects, 5% maximum for any single permanent grade, 10% maximum condition defect and 4% maximum decay for all onions. Recommended transit temp is 32ºF. Sources: PACA, DRC, USDA. Know Your Commodity References — Onions (Dry) Page 5 of 6 Copyright © Blue Book Services 1992, 2012, 2015

Know Your Commodity REFERENCES — Onions (Dry) HEALTH & NUTRITION Onions are sodium, fat, and cholesterol free. They provide dietary fiber, Vitamin C, Vitamin B6, and potassium among other nutrients. Onions contain antioxidants that evidence suggests are effective against the common cold, heart disease, diabetes, osteoporosis, and other diseases. Source: Producepedia.com.

MISCELLANEOUS Onions are used to heal blisters and boils in many parts of the undeveloped world. In the United States, products used for the treatment of topical scars contain onion extract. In Egypt, onions symbolized eternity because of the circle-within-a-circle structure and were an object of worship. Lemon juice or vinegar will remove the smell of onion from your hands. Chewing parsley or a coffee bean will freshen onion breath. Source: Producepedia.com. Know Your Commodity References — Onions (Dry) Page 6 of 6 Copyright © Blue Book Services 1992, 2012, 2015

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