Sensory attributes and physicochemical features of corn snacks as affected by different flour types and extrusion conditions

• Pumpkin flour strongly increased polyphenols level and colour intensity of corn snack.
• Pumpkin and Jerusalem artichoke flour highly increased antioxidant capacity of snacks.
• Jerusalem artichoke and pumpkin flour negatively changed the corn snack structure.
• Amaranth flour was beneficial additive in corn snacks extruded in 160 °C and 300 rpm.

The development of functional corn snacks by adding nutritional rich additives is an interesting strategy to promote the consumption of antioxidant rich ingredients, such as polyphenols. Flours made from Jerusalem artichoke tubers, amaranth seeds, and pumpkin flesh were added at level of 10% to corn grits in twin-screw extrusion at the head zone temperatures of 120, 140, or 160 °C and two levels of screw rotation speed (200 and 300 rpm). The use of amaranth seeds flour and in a lower degree of Jerusalem artichoke flour is recommended. Amaranth flour did not change significantly sensory attributes (especially the appearance and texture) of regular corn snacks and significantly increased the total polyphenols content, TPC up to 3449 mg 100 g−1 dry matter (dm), particularly when extruded at a temperature of 160 °C and a screw rotation speed of 300 rpm. The effects of Jerusalem artichoke and pumpkin on the structure of the corn snacks were so negative that preclude their used in this industrial application, even though drastic increases in the antioxidant capacity and TPC were observed.