Nutritech - Rethinking the Food Chain

PhD work: Process-induced structural features of solid cereal foams

24.3.2015 8:15


Cellular solid cereal foams, such as extruded snacks are generally made of refined wheat flour, and lacking the protective factors of whole grains may increase the risk for obesity, type II diabetes and cardiovascular diseases. Adding fibre and bran and using wholegrain would benefit the nutritional quality of this kind of foods. It is important to understand the role of structural and textural factors of different types of cereals foods, as these influences the sensory perception and dictate cephalic phase and furthermore physiological responses.

Previously it has been shown that both food structure and texture affect the size of particles resulting from mastication in mouth. However, the exact mechanisms underlying oral processing are not fully understood. Moreover, the structural models are still far behind the reality and complexity of oral processing. Thus, the PhD work of MSc Syed Ariful Alam will focus on developing understanding of the mechanisms and factors defining the structure of cereal solid foams and further disintegration and digestion of food structure.


  • Understand the main structural and mechanical features of healthy solid foams made with endosperm rye flour and/or rye bran.
  • Assess effects of structural and mechanical properties of high fibre extruded products (puffs and flakes) on disintegration in mouth (in vivo) and bolus formation.
  • Elucidate mechanism of structural disintegration of healthy solid foams (in vivo mouth and in vitro stomach phase) in comparison to refined wheat based foams (puffs and flakes).


The first two years (2014−2015) of this PhD research were financially supported by the Academy of Finland and Raisio Plc. Research Foundation. This PhD work is supervised by Nesli Sozer, Kati Katina and Kaisa Poutanen.

For more information:

Alam, S. A., Järvinen, J., Kirjoranta, S., Jouppila, K., Poutanen, K., & Sozer, N. (2014). Influence of particle size reduction on structural and mechanical properties of extruded rye bran. Food and BioprocessTechnology, 7(7), 2121−2133.


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