Development of biodegradable films from whey proteins by cross-linking andentrapment in cellulose

Citation
C. Le Tien et al., Development of biodegradable films from whey proteins by cross-linking andentrapment in cellulose, J AGR FOOD, 48(11), 2000, pp. 5566-5575
Citations number
31
Categorie Soggetti
Agricultural Chemistry","Chemistry & Analysis
Journal title
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
ISSN journal
00218561 → ACNP
Volume
48
Issue
11
Year of publication
2000
Pages
5566 - 5575
Database
ISI
SICI code
0021-8561(200011)48:11<5566:DOBFFW>2.0.ZU;2-H
Abstract
When cross-linked by heating or by gamma -irradiation and entrapped in cell ulose, whey proteins can generate insoluble biofilms with good mechanical p roperties and high resistance to attack by proteolytic enzymes. Interchain cross-linking of proteins generated an increase in the puncture strength, a nd a decrease in water vapor permeability. Gelatin was added in film formul ation as a stabilizer to improve the puncture strength and film appearance. The structure of the biofilms was also analyzed. SDS-PAGE revealed that he ating and gamma -irradiation produce an increase of the molecular weight of the cross-linked protein. Size exclusion chromatography showed a molecular mass of 40 kDa for un-cross-linked whey proteins, whereas for the soluble fractions of the crosslinked proteins, molecular distributions were between 600 and 3800 kDa for the heated proteins and between 1000 and 2000 kDa for gamma -irradiated proteins. No major alteration of the structural conforma tion of the proteins was observed by FTIR for biofilms obtained after heat treatment, whereas gamma -irradiation induced some modifications in the pro tein structure. X-ray diffraction analysis suggests that cross-linking by g amma -irradiation seems to modify the conformation of proteins, which becam e more ordered and more stable.