Film blowing of pea, wheat and oat starch

Research Project, 2025 – 2026

Background
A sustainable mix of starch, plasticizer, heat and mechanical energy can transform starch starch to a thermoformable bioplastic. RISE and Chalmers have previously cooperated on such thermoplastic potato starch and even been able the industrial technique film blowing which is difficult for native biopolymers. These films were strong and dissolved in water over time and are therefore good for applications as mulch films, packaging for oily additives (e.g. pesticides) and
even laundry handling in hospitals. High amylose content was found to be advantageous and both wheat and pea starch should therefore be suitable for film blowing due to their high contents of amylose.
Aim
To develop thermoplastic starch films based on pea, oat and wheat starch, utilizing film-blowing techniques to produce starch-based films.
Objectives
Processing Window: Determine optimal conditions for film-blowing pea and wheat starch, including water and plasticizer content, and processing conditions.
Material Properties: Evaluate the strength and water dissolution of the films.
Side stream evaluation: Assess the effect of adding fiber and protein to simulate a biorefinery stream.
Impact
Wheat starch is an existing side stream in the Lantmännen plants in Lidköping and Norrköping, oat starch in Kimstad and pea starch will be another one when pea protein production starts.
Utilisation of these streams as bioplastics will potentially be more profitable than for feed or ethanol production. In addition, if the EU decreases profitability of ethanol production, materials
applications would be even more important.

Film blowing is scalable and an industrial technique. The films produced have commercial value and applications of dissolvable films exist within the Lantmännen business areas (mulch films, packaging for oil-based agricultural additives etc.) as well as in other areas. The introduction of inexpensive bioplastic films in agriculture will improve yield of crops like vegetables which benefit from mulch films. Handling of concentrated pesticides can also be safer after introduction of dissolvable packaging which can be placed directly in water for further dilution. Water dissolvable bioplastic films also have uses in clinical handling of contaminated material as wash bags and in personal care products such as bath oils.
The findings will be disseminated through high-impact scientific journals and conferences, promoting further research and development and industrial application.