On Processing Potato 2. Survey of Products, Processes and Operations in Manufacturing


In supermarkets in the Netherlands, well over 150 potato products are displayed. They can be distinguished by heating characteristics (boiled or fried), appearance (e.g., intact tuber pieces or formed hash browns), dehydrated (e.g., snacks and flour) and storage temperature (e.g., ambient and frozen). Fancier products (frozen formed versus chilled blanched) require more processes and operations in factories and are more expensive; consumers appreciate them because they offer more convenience. Heatmapping and hierarchical clustering were carried out twice within the domain of classes of products and their attributes. In a theoretical triangulation, consumers give high scores to low prices and a wide range of products, tastes and sizes where processors give these attributes a low score. Processes in factories include dehydration, heating, cooling and transformation. Examples of the latter are modification of starch to increase the range of applications in the food industry, forming of mash and shreds to produce croquettes and hash browns and expansion to make snacks. Processes require operations such as washing, cutting, blanching and packing. In total, between the arrival of the tubers at the gate and leaving as packed products to outlets, 66 operations are distinguished. French fries undergo some 30 operations and to produce flakes, 8 suffice. Heatmapping and hierarchical clustering differentiate a group of physical operations (with attributes associated with heating and cooling that require much energy) and mechanical ones (related to separation, grading, sorting for instance and size reduction of which shredding is an example that require little energy). The wide range of operations in large factories, reducing the moisture content and longtime storage at low temperatures, distinguishes potato from wheat that has fewer operations while increasing the moisture content in relatively small bakeries and the product, bread, stored for about one day in ambient conditions.