SLU news

Better storage of sugar beets

Published: 15 June 2023
A man in front of an audience. Photo.

Sugar beets are often stored in the field over winter, and it is important to minimise losses after harvest. William English’s doctoral thesis aimed to find out how to preserve the beets in the best way possible.

Every winter, mounds of sugar beet roots dot the landscape of southern Sweden. Built from the toil of the season, these field “clamps” have been adopted as the means of minimising food loss in the period between harvest and processing. Beneath their fleece coverings hide many secrets. It is not that sugar beet growers do not have an understanding of the general state of the clamp, it is just that the scale and complexity of the system makes it difficult to fully quantify.

–  In my project, I wanted to do more than just take a peek beneath the covers. It looked to deepen our understanding in two areas. The first area was what sugar beet growers can do to impact the physical robustness of their roots, what this means for storability, and how we can easily measure this. The second area was how temperature and moisture move and vary across the entire clamp profile, says William English.

William's project was part of SLU's industrial PhD program LivsID and he worked both at SLU and at the company Nordic Beet Research.

Water availability can impact storage durability

It turned out that growing season water and nitrogen availability do not have any marked impact on the mechanical properties of sugar beet roots.

– The benefit of this is that it means growers have one less agronomic relationship to worry about. However, we also found that water availability during the season did change how well roots tolerated being in storage, says William.

Ventilation without quality loss

Great effort is usually expended to avoid dehydration of fresh produce during post-harvest

storage, as it results in a loss of quality and value. Using forced ventilation over a short period, it was found that it is possible to achieve a high rate of dehydration in sugar beet roots without loss of quality, which in-turn could lead to increased payment per harvested tonne of the crop.

How’s the weather?

Using the same method used to model if tomorrow will be dry or wet, cold or warm, the beginnings of a model of the weather across the entire sugar beet clamp profile was developed.

– This model focused just on the temperature but could use the results of the above mentioned forced-ventilation project to expanded coverage to include moisture, concludes William.


LivsID is an industry PhD-program at SLU, dedicated to research and education within food-related topics. The program involves nine companies and seven departments at SLU. The industrial PhD students are employed by the company where the project is based and conducted research in food-related applied areas. Through LivsID's activities, they also interact with each other and create a network between academia and companies. William English is the second person to defend his thesis in the program.

The program was initiated with support of the government as part of the National food strategy and established in autumn 2018 with initially 10 projects. One more project is associated. The program is running in Alnarp, Umeå and Uppsala.

Read more about the LivsID program here.


Porträttfoto av en leende man. Foto.

William English