Insights from American Crystal’s Kelly Thomas
If you are a sugarbeet grower, the growing season can be a long, hard road — from planting in the spring, to spraying in the summer, to the grueling grind of harvest in the fall. If you’re a harvested sugarbeet root, however, once you get dumped out of the trailer at the piling station, your battle is only about half over.
Click here to check out the entire current issue!
Sugarbeets can remain at the piling stations in storage for up to five or six months. If temperatures are not perfect for the beets, their quality can diminish rapidly.
“The kind of weather we’ve been having is not good. We like to see it cooler. We had some fairly warm temperatures during harvest, too, which we don’t like to see either,” said Kelly Thomas, storage research supervisor for American Crystal Sugar Company. As of early November, temperatures were far above average with more of the same forecasted for the following two weeks in Thomas’ region. “On top of that, we have a huge crop this year, which makes it so the piles don’t ventilate as well. So it’s kind of a three-edged sword we’re having to fight this year.”
Once the Red River Valley harvest is complete and all the beets are placed into storage, a very methodical and systematic approach is put in place to maximize the sugar contained within those beets and to minimize beet respiration.
Ventilation fans are turned on right away for select outdoor piles. The ventilation immediately and effectively begins to lower the core temperature of the beet and slow respiration. As a result, these beets will be among the last to be picked up and hauled to the factory for processing.
For the large percentage of beets that are not placed under ventilation, that is where the work begins. “First, we split our deep freeze piles,” Thomas continued. “They start at about 200-300 feet wide and we go right down the center and split them up so then you have two smaller piles that ventilate a lot better. With the big crop we had this year, some of our piles have reached up to 28 feet high. So we are also shoving the top off on those tall piles to get them around 20 feet tall.
“We won’t finish splitting piles until the end of December. We begin by dealing with the piles that we think are going to be troublesome earlier and we go take care of them first. Then you deal with the others as things move along.”
Thomas’ ultimate goal is to stop or slow respiration as much as possible while the beets are in storage. This preserves the sugar content of the beet and is done so by freezing the beet itself. “During the winter we freeze our ventilated piles. As soon as the temperature gets below zero, we turn the fans on and deep freeze the entire pile solid. This stops respiration completely. That saves a bunch of sugar and allows us to extend our campaign many more months than we normally would. The day you turn the fans on is the quality of beet you’ll have at the other end when you process it.
“Under normal circumstances [without deep freezing], we’d better be done processing by the first of March. But because of deep freezing, we have been able to run as late as the first of June. So it allows us to process more beets, which ultimately allows the growers to grow more beets. However, you want to be [done with the outdoor piles and] into the refrigerated sheds by the beginning of May because things are melting down pretty good by then.”
A lot of work is done to insure the beets remain frozen that late into the spring. Tarps are placed over the piles and storage sheds are insulated. Beets within storage sheds are also covered with a pillow tarp that has tubes run up over the pile. Air that is chilled below zero is blown up through the tubes on top of the insulation, which acts as another barrier for the beets.
This year American Crystal is also utilizing another tactic to keep their outdoor piles as cool as possible in the fall. Passive ventilation is used for smaller piles and employs natural airflow to cool the beets. “We’ve actually had passive ventilation for a number of years, but we are now just trying it under smaller split piles. We are putting the ventilation under the piles with no fan, and it is working pretty good so far.”
There are obvious differences between storing outdoors and in a storage shed. Beyond that, however, both have their benefits.
“The big thing with the shed, compared to an outside deep freeze, is the outside layer of beets is not affected as much. With outdoor storage, you have less control of the air flowing in and out of the pile because there is natural ventilation. When you put them in a shed, you have ultimate control. You can keep the sun off the pile, it doesn’t freeze-thaw, you can control the air and the temperature in and out of it, so you can control the beets in a very specific range. You do not have as much control with an outside pile so you will develop a layer on the outside called ‘rim beets.’ Those beets get pretty beat up; there is virtually no sugar in the outside layer because they freeze-thaw and have high respiration. They basically burn up all the sugar within the beet. When the temperature gets below freezing at night and warm during the day, rim beets are made like crazy.”
Despite all of those advantages, storage sheds are costly to put up and maintain, which make them less available than the traditional outdoor storage facility.
In a follow up interview in late November, Thomas gave an update on how the beets stood following those unseasonably warm temperatures.
“The non-ventilated stuff...it has taken a hit,” he said. “Any time you get warmer temperatures like that, it’s not good. We lost a little more sugar, but it hasn’t been anything too terrible. As far as the ventilated beets, we are in really good shape. We’ve been able to keep the temperatures in those piles down pretty decent.”
Now that the temperatures have leveled off consistently near or below freezing, at least for the time being, there is a good outlook for the beets contained in outdoor storage.
“We pretty much have the ventilated beets right where we want them. In the non-ventilated, we are still trying to get them split open and cooled down a little more. We are certainly happy about the cooler temperatures, it is definitely helping us out. But it’s as good as it’s going to get. That’s the thing with this storage stuff. You take the weather you get and try to make the best of it.” – Mike Spieker
Editor & General Manager of The Sugarbeet Grower