21 February 2020

The quality of potatoes in every sense

The culinary and technological quality of a potato grown for consumption is an indication of its suitability for eating, preparing or processing according to an expected use. This is a crucial data set for marketing.

The quality of potatoes in every sense

As with the production of other vegetables, the quality of potatoes is dependent on a series of factors, some of which relate to choices made by the producer (variety, crop management) and some of which do not (climatic conditions). To obtain a quality potato it is therefore essential to meet the final requirements expected for a given variety. This calls for detailed knowledge of production and conservation techniques, regular monitoring at the end of the cultivation period and uprooting under favourable conditions.

At the CRA-W Haute Belgique building in Libramont, a laboratory has been specialising, since the 1970s, in the development and implementation of sensory analysis dedicated to potatoes. This involves analysing the organoleptic properties of samples using the 5 senses: sight, smell, touch, taste and, in rare cases, hearing. What sets the laboratory apart is the wide range of analytical methods offered and the expertise of a team that can adapt to changing analytical needs. This is because, in the past fifteen years, the valuation of potatoes has become divided and diversified, with increasingly complex, specific demands: new potatoes, French fries, varieties for microwave cooking, etc.

In practice, the analysis is carried out by expert staff according to rigorous protocols developed at the CRA-W (assessment of sub-epidermal spots or "blue bruises", definition of 9 sensory descriptors) or more widely shared criteria (colour after frying ). A tasting jury made up of CRA-W staff members has also been trained and is mobilised according to requirements.

The laboratory was originally established to meet the needs of the potato breeding programme of the time. On the one hand, the analysis currently forms part of the research programme: improving the potato, studying the impact of cultivation or conservation practices on quality, the description of new varieties; on the other hand, a number of private customers are requesting CRA-W expertise: mass distribution, specifications of differentiated quality (Plate de Florenville), potato packers/preparers, producers, etc. As a result, 460 samples were analysed in this laboratory during 2019.