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NuSun Testing More Routine

Saturday, September 1, 2001
filed under: Utilization/Trade: NuSun

NuSun Testing Becoming Routine

More country elevators are sampling properly to ensure mid-oleic sunflower makes the grade, which this year includes a new 55% rejection point at processing plants

Testing and sampling for NuSun is becoming more of a routine task at country elevators in sunflower production areas, and that’s good news, because no one in the industry from seed companies and growers to country elevators and processors want surprises from seed that doesn’t make NuSun’s mid-oleic grade.

Lori Grieger, grain inspector for the North Dakota Grain Inspection Service, Enderlin, says the testing process to determine whether loads qualify for the NuSun premium went much smoother last year compared to 1999, when sunflower didn’t reach full maturity in some growing areas, and few elevators were equipped for testing. “A lot of elevators got burned in 1999. They took sunflower in as NuSun, brought them to the processing plants and they didn’t make it. And all of a sudden we had this huge interest in testing at the local level,” says Grieger.

Last year brought improved NuSun hybrids with more stable oleic acid levels, backed by guarantees by most seed companies that the hybrids would make the mid oleic grade. Also helping significantly was a plan put in place by the National Sunflower Association’s NuSun Committee to encourage the use of hand-held refractometers to test for NuSun as ‘flowers are brought in to country elevators. “I can say that if you want to find any complaints, you’ll have to talk with someone else, because I didn’t have any last year,” says Grieger. She adds that some loads were rejected by processors last year. However, most of the rejected loads were “on the bubble” and questionable in making the NuSun grade, so their rejection didn’t come as a surprise to most shippers.

The Sampling Process

The refractive index method of testing for oleic content was first developed by the companies purchasing high oleic sunflowers over a decade ago, says Grieger. Because the control of their highly specialized product was so closely monitored through seed sales and contracting, testing at the elevator level was generally not an issue. “This is not the case with NuSun, and a quick and inexpensive method of testing was a necessity,” she says. “Since that time we have adapted and refined those original testing methods to fit the needs of the elevators receiving NuSun at the local level.”

The NDGIS provides sample bottles of NuSun oil to country elevators, along with a brochure describing the sampling process. About 65 sampling kits went out to various elevators in the Northern Plains since last harvest, and about 20 in the High Plains. Grieger expects more to be distributed as the 2001 sunflower harvest gets underway.

Last year, samples of 50% and 55% oleic levels were sent out and elevators had the choice of which to use. This year, samples of 55% and 60% oleic levels will be distributed to elevators, to reflect the new 55% rejection point at the processing plants for NuSun. Loads failing at the elevator will be tested by the seed companies on a more precise basis to determine payment of guarantees, and the extra 5% gives the elevator a buffer zone for testing.

Elevators collect a representative sample of the load, probing to the bottom of the load in several locations, mixing the seed and selecting the sample size from that mix. The sample must be free from foreign seeds and at room temperature.

Oil is extracted from the sample using a small hydraulic press. Grieger credits Ron Rivenes, who has a welding and machine shop in Onida, S.D., for developing a press specifically for NuSun sampling.

In the NuSun sampling process, she suggests using the full volume of the press’s extraction cup to allow for a representative sample. Several drops of the oil are placed on the lens of a handheld refractometer, and the reading is compared to the reading taken from NuSun calibration oil provided by the NDGIS.

The pass/fail reading indicates if the sample is oleic or traditional linoleic seed. The refractometer doesn’t provide an exact numerical oleic number, but clearly indicates if the seed is traditional linoleic sunflower, or if the NuSun has been mixed in. If the reading is inconclusive, the elevator operator is advised to repeat the test or even resample the load. If the second test is inconclusive, Grieger recommends that the elevator send a seed sample to one of the crushing plants for a more sophisticated test, which can be done quickly.

IP Key to NuSun Quality, Premiums

Identity Preservation (IP) is the key to preserving the quality of NuSun oil, as well as premiums paid for it. Oleic acid is one of the major factors in the oil that provides shelf life, and supplying a consistent level of oleic acid in the mid 60s range is critical for continued use and market growth of the product, says industry leaders. “Putting NuSun sunflower seed into the right bin is not only important to the producer to ensure a premium, but it is equally important to the crusher and the oil buyer,” says Larry Kleingartner, executive director of the NSA.

It’s critical for ‘flowers to be sampled for NuSun at the country elevator level, says Grieger. “It takes one load of regulars to wreck a whole bin of NuSuns,” she says. It’s important to understand that regular sunflower can’t be blended with NuSun, the same way that wheat can be blended to arrive at a certain protein level. “Oleic on regulars is about 18%, and it needs to be about 55% for NuSuns. It’s not like percent protein where mixing 12.5% and 13% protein wheat is going to blend up to a 13%. It doesn’t work that way with oleic.”

More elevators are looking at NuSun testing equipment as an investment, realizing that it's worth the cost. An elevator will spend about $500 for the hydraulic press and around $275 for a refractometer. “If you ruin even one load at 50 cents/cwt, that’s $300. If you ruin a bin, that’s about three loads, and preventing that has more than paid for your equipment,” says Grieger.

Mark Pederson, grain merchandiser for Midwest Co-op, Pierre, S.D., agrees that the testing equipment is worth it. “We got it before last fall’s harvest, and it’s been working out good. Of the ‘flowers we’ve tested, we haven’t had anything go against us when we’ve delivered it.” Roger Larson, who manages the Karlstad (Minn.) Farmers Elevator, sees less sunflower volume than other country elevators, but invested in the NuSun testing equipment nonetheless. He agrees too that it has already paid for itself in catching sunflower that didn’t make the NuSun grade.

Ryan Hill, field representative with Northern Sun in Goodland, Kan., says more country elevators in the High Plains are investing in NuSun testing equipment. His company helps put elevator operators in touch with equipment suppliers. Hill points out that it can take up to 30 days for testing equipment to be shipped by suppliers, so elevators shouldn’t wait until the last minute to order.

For more information about NuSun sampling and testing, contact Grieger at the NDGIS, ph. 701-437-3000, ext. 202, or by email, More information about NuSun sampling and testing can also be found online at The NSA is also a resource, and can be contacted toll free at 1-888-718-7033.  Tracy Sayler

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