Stay informed of the latest news of NSure

Storage sweetening predictable in potatoes

NSure introduces an innovative assay for the potato processing industry

 An important quality characteristic of processing potatoes is the sugar content. Too much sugar results in a unwanted dark frying color. During storage the tubers will always convert part of the starch into sugars. It takes an expert’s skill to ensure that this storage sweetening remains within acceptable limits until the moment that the potatoes will be processed.

Farmers and industry rely on their expertise and on occasional frying tests. Still it remains difficult to estimate the quality of a batch. Misestimates often make necessary extra processing steps in the factory or ultimately may result in rejection of the batch.

NSure, an innovative company based in Wageningen, the Netherlands,  is now presenting an answer to these kind of problems. Last week NSure introduced a new decision support tool for potato growers and processing industry. It concerns a highly innovative assay that discriminates between potato batches that are low or high risk with respect to sweetening. The risk prediction can be done at harvest time  and is based on measuring the activity profile of a selected set of potato genes. NSure is specialized in this molecular test technology.  

Monique van Wordragen, NSure’s managing director, explains: “All biological processes in a potato tuber are ultimately driven by the genes that act as molecular switches. They can be turned “on” or “off” and thus direct the developmental changes. Maturation of a tuber is a highly complex process. Dozens of genes are involved that interact with each other and are influenced by conditions during growth and storage. NSure sort of reads out the ‘Black Box’ of the tuber. We determine which genes are active and use that information to draw conclusions on the quality of the tuber at harvest time.” 

This approach has resulted in an assay, called FryNSure, that gives much more information than is possible with the standard frying color of sugar measurements. The result communicated to the customer is a classification in one of three risk categories. The main advantage of the FryNSure test is that it predicts the risk for high-sweetening several months in advance. This allows for more efficient logistics with respect to storage and processing. High risk batches can be processed first.    Though the FryNSure test is a high tech achievement, it is very easy to use. An NSure sampling kit contains specially prepared sample cards that are loaded with a single drop of extract from the tubers. The card stabilizes the sample and allows it to be sent by regular mail to one of the NSure test laboratories. The result report is communicated within 2 working days.    

 

The FryNSure test is developed in co-operation with the Association of Potato Processing Industry (VAVI) and the Wageningen Research Institutes AFSG and CBSG.  At present the test is only available for  Agria potatoes, but will be extended to other varieties in the coming two years.