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Nesho Georgiev Toshkov Ventsislav Nenov Nenov Bojidar Bozadjiev Naiden Delchev Erik Valov


Extrusion of wheat semolina and milled cocoa shells using a single screw extruder Brabender 20DN was carried out. Full factorial experiment 23 was used to investigate the effect of the quantity of cocoa shells, moisture of the material and temperature of the matrix on the density and expansion index of extrudates. Feed screw speed and screw speed were fixed at 30 and 200 rpm, respectively. Compression ratio of the screw was 4:1. Expansion index values range between 2.0 and 3.36 and a density between 0.099 and 0.223 g/cm3. The increase in moisture content and quantity of cocoa shells leads to a decrease expansion index, while density of extrudates an increase.

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How to Cite
TOSHKOV, Nesho Georgiev et al. Extrusion of wheat semolina and cocoa shells. Food Science and Applied Biotechnology, [S.l.], v. 4, n. 2, p. 177-182, oct. 2021. ISSN 2603-3380. Available at: <>. Date accessed: 28 oct. 2021. doi: