Title: HPMC reinforced with different cellulose nanoparticles Authors
Submitted to: Carbohydrate Polymers
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 21, 2011
Publication Date: October 15, 2011
Repository URL: http://www.elsevier.com
Citation: Bilbao-Sainz, C., Bras, J., Williams, T.G., Senchal, T., Orts, W.J. 2011. HPMC reinforced with different cellulose nanoparticles. Carbohydrate Polymers. 86(4): 1549-1557. Interpretive Summary: In the food, agricultural, pharmaceutical and cosmetic industries there is strong interest in creating new products based on starch and oil systems in which emulsions and nano-emulsions can be used as delivery systems for non-polar functional components. These systems require microbial, chemical and physical stability as an important quality criterion. We obtained a stable starch-lipid composite by mixing a completely gelatinized HACS solution with emulsions containing cinnamaldehyde as antimicrobial agent. We observed an increased stability when using emulsifier. In this case, the homogenizer was capable of forming smaller droplets, as the size of the oil droplet decreased, the starch-lipid interface increased facilitating the formation of amylose-lipid inclusion complexes. We also proved the antimicrobial properties of the composites against Listeria monocytogenes. The composites produced from nanoemulsions were more efficient in killing the bacterial cells as compared with the composites produced from emulsions. The effectiveness of the nanoemulsion was attributed to the higher surface area of the lipid droplets containing cinnamaldehyde in contact with the microoganisms.
Technical Abstract: The formulation of a starch-lipid composite containing cinnamaldehyde as antimicrobial agent has been studied. Cinnamaldehyde was incorporated as an emulsion using Acetem 90-50K as a carrier and Tween 60 as the emulsifier. Oil in water emulsions were prepared by direct emulsification using a high shear mixer or a high pressure homogenizer (Microfluidizer). Oil in water emulsions containing cinnamaldehyde were further used to prepare starch-oil composites by mixing the emulsions with a completely gelatinized starch solution (waxy starch, native corn dent starch and high amylose corn starch). Results demonstrated that in the presence of the emulsifier Tween 60, stable composites could be obtained when sufficient amount of amylose was present in the sample. Finally, stable composites were tested for its biocidal activity against Listeria monocitogenes; no survivors reminded after 1 day of incubation with 0.25 % cinnamaldehyde or after 7 days with 0.025% cinnamaldehyde.