Physical quality of snacks and technological properties of pre-gelatinized flours formulated with cassava starch and dehydrated cassava bagasse as a function of extrusion variables

In cassava industrialization, starch is produced, but residues are generated, including bagasse, which has high moisture content and is generally not availed, creating a serious environmental problem. The objective of this work was to study the effects of moisture (12-20 g 100 g−1) and extrusion temperature (61.7-118.3 °C) on the expansion and color of snacks, and on functional properties of pre-gelatinized flours formulated with cassava starch and dehydrated cassava bagasse (70:30), to verify the possibility of extending the application of this co-product. Response surface methodology and analysis of variance were applied. The moisture of the mixture and the extrusion temperature significantly affected physical properties of snacks and functional properties of pre-gelatinized flours. Snacks lighter and yellowish with larger expansion index and intermediate specific volume were obtained at the extrusion temperature of 104.1 °C and moisture of 16 g 100 g−1. Pre-gelatinized flour with high absorption rates, solubility in water and oil absorption were obtained at extrusion temperatures of 90 °C and moisture of 16 g 100 g−1. It is viable to use the dehydrated cassava bagasse and cassava starch (30:70) in the production of snacks and pre-gelatinized flours.