How do you keep the kilos in the crate during the storage of the potatoes? ENGIE Refrigeration, specialist in refrigeration technology and partner of the Boerenbusiness Crop tour, has the answer. Condensation drying allows potatoes to overwinter with minimal weight loss.
In part 2 of this diptych ENGIE project leader Marcel Bennink explains how this is possible about this technology. Keep the kilos in the box for a winter. Get on it. With conventional storage technology, you as a grower are dependent on the outside air.
Constant temperatures
The outside air appears to be the culprit. "If you want to stop the activity in the potato, a constant storage temperature is required. But the outside air temperature varies. Too much heat causes condensation and loss of moisture and when it is cold, the potato produces sugars to bring it up to temperature again. Is the potato cooling too far? and a period of warm weather follows, then you can no longer ventilate without the potato heating up again. The product temperature is therefore often forced to be (too) high," says Bennink.
Depending on the weather, potatoes lose up to 15% of their weight in a conventional storage facility. This increases with a warm winter. In addition, the unpredictability of the weather is increasing. Farmer Jan Goense knows all about it. ENGIE made sure that its storage space is no longer dependent on the outside air. "Last winter it was an average of 10 degrees Celsius. I was happy that I no longer had to cool with outside air, then I would have seen my products dry out under my nose."
Dealing with uncertainties
With condensation drying, ENGIE eliminates the outside air and eliminates uncertainties. The potatoes are stored in an almost closed space (at a constant temperature and maximum CO2values). By blowing in only slightly cooler air, the storage area is brought to the desired temperature. Because CO2 heavier than air, it sinks to the bottom. The system monitors the conditions and pulls the blanket of CO2 away. The conditions of the outside air no longer determine the quality of the potatoes, but the potatoes determine the conditions.
Bennink: "Due to the stable conditions, the potatoes remain of the best quality, with a maximum of 3% dehydration. Organic products in particular benefit from this, because they are more sensitive to storage losses. The longer growers can store the potatoes without loss of quality, the greater the chance that they can trade them when the price is highest. The trick is not only to limit weight loss, but also to use energy-efficient cooling. Due to the constant and predictable energy consumption, the energy bill is also much lower."
Future-proof
Jilles Boer of potato company Boer de Jong shares his experience: "Since one variety germinates faster than the other, I have 2 cold stores with different temperatures. One cools at 4,5 degrees Celsius, the other at 6 degrees Celsius. my potatoes at the temperature that is appropriate for their species and they retain the quality they have when they come off the land, they do not germinate, do not lose size and weight. this installation."
More kilos
Arable farmer Eugen Borgmann from Bottrop in Germany also enjoys more kilos after storage thanks to the condensation drying system. "We've achieved less than 3% dehydration," he says. "Damaged or rotten potatoes are mummified in the crate, preventing them from contaminating the surrounding good potatoes."
Borgmann continues: "This season we have been able to process and trade 30% more marketable product. Due to the excellent quality, we received a good price for our potatoes until late in the season. And because they retain their moisture and remain much firmer, we have less loss during the peeling of the potatoes. Previously, cooling in a mild winter cost a lot of electricity. Because mechanical cooling keeps the temperature constant all year round, energy costs have fallen significantly."