Minn-Dak's  shareholders produce sugarbeets for processing at the cooperative's plant in Wahpeton

Minn-Dak Farmers Cooperative members have processed their sugarbeets at the plant in Wahpeton since 1974. But before that process starts, the annual sugarbeet harvest needs to be completed.

Rainy weather made for a rocky start to the main sugarbeet harvest that got underway at 7 a.m. on Oct. 4. However, crops look good, said sugarbeet analysts. Although the final production numbers aren't in, the year looks better than expected.

“It’s a tricky thing weather-wise,” Minn-Dak Farmers Cooperative Agriculturist Mike Metzger said Tuesday in reference to the annual sugarbeet harvest. “We like weather to be cool, but not freezing. If it’s too wet the beet farmers can’t get into their fields. And we don’t want to see temperatures too high.”

Minn-Dak is a member/owner of two marketing cooperatives — United Sugars Corporation (USC) in Minneapolis and Midwest Agri-Commodities (MAC) in San Francisco. Minn-Dak markets its sugar through USC and markets co-products, including beet molasses and beet pulp pellets, through MAC.

USC is the second largest sugar marketing organization in the country, consisting of Minn-Dak, American Crystal Sugar Company of Moorhead and United States Sugar Corporation of Clewiston, Fla.

At the factory in Wahpeton, sugarbeets are washed and sliced into thin strips called cossettes. The cossettes go through a large tank called a diffuser where raw juice is extracted.

The cossettes are gently lifted from the bottom to the top of the diffuser as hot water washes over them — absorbing the sugar. After the sugar-laden raw juice is drawn off, the beet pulp is left behind. This pulp is processed separately into pellets for livestock feed and other products.

The raw juice is mingled with milk of lime and carbon dioxide gas in carbonation tanks. The carbon dioxide bubbles through the mixture forming calcium carbonate. The non-sugar particles attach themselves to the calcium carbonate and settle to the bottom of the tanks.

The juice is then filtered, leaving a golden light brown clarified thin juice. This juice is boiled under vacuum where much of the water is evaporated, forming a thicker juice similar to pancake syrup.

After a second filtration to ensure that all non-sugar materials are removed, the juice goes to the boiling pans. Once again the juice is boiled under vacuum and crystals begin to form. The resulting sugar crystal and syrup mix is called massecuite.

The massecuite is then sent to centrifuges for separation. By spinning rapidly in a perforated cylindrical basket, the syrup is thrown off through the screen holes. Clean hot water is used to wash the sugar, producing pure white sugar crystals.

The damp crystals are dried with filtered air in a rotating drum granulator and the dried sugar passes over screens which separate the various sizes of sugar crystals. The products are then packaged and shipped to grocery stores and food manufacturers.