The Effect of Onion Skin Powder Addition on Physical Parameters of Extrudates

Extrusion is one of the popular processes to produce functional foods with different texture and structure. The addition of onion skin to the wheat extruded product can improve the nutritional quality in the terms of fiber. The effect of onion skin addition on the physical parameters of extruded products was investigated. For the study, the non-onion skin added control samples were compared with the 3, 6 and 9% (w/w) onion skin added extrudates. The extrusion conditions were 150ºC final zone temperature and screw speed of 250 rpm. Bulk density, volume expansion index, longitudinal expansion index and porosity results showed significant difference between samples. When the onion skin amount increased, the bulk density increased while SEI (sectional expansion index) and VEI results decreased. The L*, a* and b* color analyses indicated a difference with increasing onion skin amount. According to texture analysis, control had lower hardness and higher fracturability compared to onion skin added products.
Citation Formats
B. Tonyalı, İ. Şensoy, and B. Mert, “The Effect of Onion Skin Powder Addition on Physical Parameters of Extrudates,” presented at the 4th International Conference and Exhibition on Food Processing & Technology. ( August 10-12, 2015), London, UK., 2015, Accessed: 00, 2021. [Online]. Available: