| Summary: | This PhD dissertation focuses on the development of renewable and
biodegradable active films based on chemically-modified wheat gliadin
proteins endowed with antimicrobial capacity owing to the incorporation
of naturally-occurring bioactive compounds, namely cinnamaldehyde,
natamycin, and lysozyme.
Gliadin proteins were treated with cinnamaldehyde at acidic pH and films
were produced by casting. The resulting protein-based films presented
improved functional properties (mechanical, barrier, and water
resistance), and biochemical evidence of the formation of a more
compact network whose degree of cross-linking increased with the
amount of cinnamaldehyde incorporated into the gliadin-ethanolic
solution.
Free cinnamaldehyde not participating in the cross-linked reaction
remained entrapped in the protein matrix at low relative humidity
conditions. The sensitivity of the films to moisture owing to the
hydrophilic character of gliadins provided a trigger and control
mechanism for the release of cinnamaldehyde in moderate and high
relative humidity environments, similar to conditions occurring in
packaged food products.
The antimicrobial properties of the films developed were tested in vitro
by vapor diffusion assays against common food spoilage fungi (Penicillium
expansum and Aspergillus niger), showing great effectiveness. Application
of these active films to the preservation of two foodstuffs, sliced bread
and cheese spread, gave promising results, lengthening fungal growth lag
phase and minimizing fungal growth extension. === Balaguer Grimaldo, MDLP. (2015). Development of active bioplastics based on wheat proteins and natural antimicrobials for food packaging applications [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48520 === TESIS === Premiado
|
|---|
