Determination of expansion ratio and diameter of extrudates with the addition of selenium enriched wheat

Ekstruzijsko kuhanje predstavlja jedan od najznačajnijih jediničnih procesa u proizvodnji hrane, gdje se vrlo često kao osnovna sirovina upotrebljava kukuruzna krupica. Zbog poboljšanja fizikalno-kemijskih osobina i nutritivne vrijednosti proizvoda, u kukuruznu krupicu se mogu dodavati brašna različitih žitarica, osušeno voće, povrće i dr. Cilj ovog rada bio je utvrditi utjecaj dodatka pšenice obogaćene selenom u kukuruznu krupicu (omjer krupica:pšenica=90:10; 80:20; 70:30; 60:40) na ekspanzijski omjer i dijametar ekstrudata. Smjese vlažnosti 15 % ekstrudirane su pri tri temperaturna profila: 140/170/170 °C; 150/180/180 °C i 160/190/190 °C, uz upotrebu puža konfiguracije 4:1 i sapnice promjera 4 mm. Dobiveni rezultati su pokazali da su se povećanjem dodatka pšenice obogaćene selenom smanjili ekspanzijski omjer (EO) i dijametar ekstrudata (de).Extrusion cooking is one of the most important processes in food production, where corn grits are often used as a main raw material. In order to improve physical and chemical properties and to increase nutritive value of the product, corn grits are often enriched with different types of flour, dried fruits, vegetables etc. The aim of this study was to determine the effect of selenium enriched wheat addition to corn grits (ratio grits:wheat = 90:10; 80:20; 70:30; 60:40) on the expansion ratio and extrudate diameter. Prepared samples with 15% of moisture content were extruded at three temperature profiles: 140/170/170 °C; 150/180/180 °C and 160/190/190 °C, using screw with compression ratio 4:1 and die with 4 mm diameter. The obtained results showed that increasing the addition of selenium enriched wheat resulted in decrease of both expansion ratio (EO) and extrudate diameter (de)