Ancient grains can improve extruded snacks: Study

Gluten-free grains amaranth, quinoa and kañiwa can be used to develop novel corn-based extruded snacks with improved expansion and softness, finds new research.

The study published in the Journal of Cereal Science investigated the use of the three gluten-free grains in extruded corn-based snacks to see if parameters like expansion and texture were impacted.

Amaranth, quinoa and kañiwa have gained industrial and scientific attention not just because of their potential as gluten-free cereal substitute, but also due to their high protein and fiber content, the researchers said.

“This study proved that it was possible to increase sectional expansion index [of the extruded snacks] by adding amaranth, quinoa and kañiwa to pure corn flour,” the researchers wrote.

Findings showed that the amaranth created the best expansion in the corn snacks, but quinoa and kañiwa still showed better expansion than regular corn snacks.

In terms of storage, all snacks made using the ancient grains showed “remarkable stability” when exposed to high relative humidity.

“This investigation was a step forward in the understanding and developing of novel gluten-free snack products,” the researchers said. They added the findings were particularly interesting given the use of extrusion technology which is low energy.

Extrusion processing impacts

When using the three grains to make extruded snacks, water content and screw speed had important impacts on the level of expansion and hardness.

“Sectional expansion index increased with increasing screw speed and decreasing water content mass,” the researchers wrote.

Decreasing the water content mass had the greatest impact on the extrudates, they said, as it increased expansion and decreased hardness.

Study details

The ancient grains were cleaned and milled into flours and mixed with corn flour; gluten-free according to EU legislation as it contained less than 20 ppm of gluten.

The flours were mixed with a 80:20 ratio of corn flour and each ancient grain flour - amaranth, quinoa and kañiwa.

 

Source: Journal of Cereal Science

Published online ahead of print, doi: 10.1016/j.jcs.2013.04.003

“Use of amaranth, quinoa and kañiwa in extruded corn-based snacks”

Authors: JMR. Diaz, S. Kirjoranta, S. Tenitz, PA. Penttila, R. Serimaa, A. Lampi and K. Jouppila