Aleksander Hejna1, Mariusz Marć2, Daria Kowalkowska-Zedler3, Agnieszka Pladzyk3, Mateusz Barczewski4. 1. Department of Polymer Technology, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland. 2. Department of Analytical Chemistry, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland. 3. Department of Inorganic Chemistry, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland. 4. Institute of Materials Technology, Poznan University of Technology, Piotrowo 3, 61-138 Poznań, Poland.
Abstract
This paper investigated the impact of twin-screw extrusion parameters on the properties of brewers' spent grain. The chemical structure, antioxidant activity, particle size, and color properties, as well as the emission of volatile organic compounds during extrusion, were investigated. The main compounds detected in the air during modifications were terpenes and terpenoids, such as α-pinene, camphene, 3-carene, limonene, or terpinene. They could be considered as a potential threat to human health and the environment. Changes in the chemical structure, antioxidant activity, and color of materials after modification indicated the Maillard reactions during extrusion, which resulted in the generation of melanoidins, especially at higher temperatures. This should be considered an exciting feature of this treatment method because modified brewers' spent grain may improve the thermooxidative stability of polymer materials. Moreover, the impact of the brewers' spent grain particle size on color and browning index used to determine the melanoidins content was investigated. The presented results show that proper adjustment of extrusion parameters enables the preparation of brewers' spent grain with the desired appearance and chemical properties, which could maximize the efficiency of the modification process.
This paper investigated the impact of twin-screw extrusion parameters on the pron class="Chemical">perties of brewers' spent grain. The chemical structure, antioxidant activity, particle size, and color properties, as well as the emission of volatile organic compounds during extrusion, were investigated. The main compounds detected in the air during modifications were terpenes and terpenoids, such as α-pinene, camphene, 3-carene, limonene, or terpinene. They could be considered as a potential threat to human health and the environment. Changes in the chemical structure, antioxidant activity, and color of materials after modification indicated the Maillard reactions during extrusion, which resulted in the generation of melanoidins, especially at higher temperatures. This should be considered an exciting feature of this treatment method because modified brewers' spent grain may improve the thermooxidative stability of polymer materials. Moreover, the impact of the brewers' spent grain particle size on color and browning index used to determine the melanoidins content was investigated. The presented results show that proper adjustment of extrusion parameters enables the preparation of brewers' spent grain with the desired appearance and chemical properties, which could maximize the efficiency of the modification process.