POTATO EXTRUDATES (Solanum Tuberosum L. cv. Orchestra): TECHNOLOGICAL PROPERTIES

The search for regional raw materials has led to the development of products with greater added value, which are versatile, sustainable, innovative and contribute to the technological properties of the products. The study evaluated the extrusion process parameters, microstructure and technological properties of potato extrudates of the Orchestra variety, with a view to potential applications. The results of the Orchestra potato extrudates were determined using the mean and standard deviation. The potato from the city of Pouso Alegre, MG, Brazil, was processed into flour and then put through a twin-screw extruder with a humidity of 18% and a process temperature varying between 70 and 120°C until the extrudates were obtained. The potato extrudates had an area of 92.40 mm, porosity of 14.43%, presence of native starch granules, hardness of 127.50 N, expansion of 2.63 and medium brown color (L* of 39.91; a* of 8.29 and b* of 28.26). The characteristics of the extrudates are possibly related to the low humidity of the feed, the temperatures of the zones and the structure of the starch of the Orchestra variety. Potato starch is usually resistant to the extrusion process due to its semi-crystalline structure, which, together with the low humidity, causes partial gelatinization on the surface of the starch. This explains the glassy, expanded, rigid appearance, thick walls and low porosity of the potato extrude. Water acts directly on the plasticization of starch, where a greater amount of water reduces the glass transition temperature and accelerates the transformation of the state of the starch from glassy to plasticized. Potato extrudates have relevant technological properties and can easily be transformed into new raw materials such as pregelatinized flours, providing practicality for the consumer, as well as acting mainly as a thickener in food products.