Bruise Control
University of Florida Research uses ‘Super Spud’ to measure impact forces on potatoes
Bruising leaves a heavy economic impact on many potato growers, resulting in the postharvest loss of thousands of dollars. But bruising is difficult to control because the bruises don’t appear until long after harvest, preventing growers from locating impact points.
At the University of Florida (UF) researchers are working to resolve this problem. At the department of Horticultural Science they are using a computer to find impact points from harvest through transportation and packing, offering growers a potential means to locate impact spots before bruising strikes.
“Most bruising won’t show up until you go into storage, so when (growers are) grading these potatoes the bruising shows up down the line,” said Steven Lands, UF/IFAS agricultural agent, St. Johns County. Lands has been a leader of the research project for the past three years.
“What we’re trying to do is determine the impact the bruising has had after the potato has gone from the farm on the truck, into storage, etc.”
The project, known as Super Spud, is in its third year of research at the Florida Partnership for Water, Agriculture & Community Sustainability at Hastings, a UF research center in the Tri-County area of northeastern Florida, which consists of St. Johns, Flagler and Putnam counties. The research is performed on both university and private lands.
Super Spud uses a potato-sized computer, known as an Impact Recording Device (IRD) to measures G-forces to locate bruising pressure from farm to packinghouse, whether on the truck or packinghouse conveyor belts.
The project begins in the field, where the IRD is harvested with the crop. The IRD is picked up by the harvester and measures impact forces throughout the harvesting and packing process, though it can be tailored to focus on either harvest or packing. As the G-forces impact the potatoes, those pressures are transmitted to a computer that records the location and pressure on the IRD, based on G-force settings calibrated in the potato-sized computer before harvest.
“We start with a minimum G-force rating of 50. Anything higher than 50 is usually recorded,” Lands said. “You want to stay between 50 Gs and 110; 120 and above is when you start to get bruising.”
The instant transmission of pressure points offers growers the opportunity to address these problem areas to lessen, or even prevent, bruising. Growers can create best management practices (BMPs) to improve potatoes before they even enter storage.
That includes widening the mouth of potato carts to prevent squeezing, adjusting conveyor belt drops and padding impact points in many places they occur. These BMPs may not solve all bruising, but they go a long way in increasing marketable potatoes.
Prim Parker is a grower who has seen a return on investment from Super Spud, and has been a part of the project from the beginning. Parker grows chip varieties, mostly Atlantics, on 400 acres near Hastings. Because of that he stores little of his crops, but that hasn’t stopped him from taking advantage of Super Spud or using the technology to create BMPs for better efficiency.
Parker ran the IRD through his harvester and packinghouse and found a drop on the harvester was problematic.
“What we saw was all the drops were excellent except for one drop on the harvester – it bumped into the sidewall of the boom,” he said. “(The IRD) let us know where we had some impact points and we remedied that. We put some padding in the location the potatoes were bumping up against.”
Super Spud has been focused primarily on potatoes, but the research has branched out into other crops, especially cucumbers, with similar results.
For all the success researchers have found through Super Spud the project is far from finished, and several more years of research are planned before the project is over.
“We will continue hopefully until we document all the farms in the Tri-County area, including both table stock and chip growers,” Lands said. “We want to work until everyone gets it that wants it.”
Whether that will boost Florida’s potato industry remains to be seen, but for each grower who has allowed the project into the fields that could result in thousands of dollars saved through marketable potatoes – potatoes that may have been rejected without the project.
“If we can reduce bruising on the potatoes by 1 percent we can make an economic impact between $10,000 and $30,000, depending on the size of the farm,” Lands said.
Photo courtesy of Stephen Lands
