Author
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 12/28/2004 Publication Date: 7/16/2005 Citation: Avena Bustillos, R.D., Olsen, C.W., Olson, D.A., Chiou, B., Yee, E., Mc Hugh, T.H. 2005. Water vapor permeability of mammalian and fish gelatin films. Meeting Abstract No. 54D-4. IFT Annual Meeting. July 2005. New Orleans, LA. Interpretive Summary: Technical Abstract: Gelatin from marine sources (warm and cold water fish skins, bones and fins) is a possible alternative to bovine gelatin without the risk associated to BSE outbreak. However, low gelling and melting temperature, and low gel modulus makes fish gelatins unsuitable for most mammalian gelatin applications. Currently there is no research on water vapor permeability of fish gelatins and their excellent film-forming properties, and potential high barrier efficiency can have applications for edible films and coatings. Our objective was to evaluate water vapor permeability of different types of mammalian, warm and cold water fish skin gelatin films and to relate it to protein molecular weight distribution, amino acid composition and gel properties. Mammalian, warm and cold water gelatins were obtained from commercial sources. Alaskan pollock and salmon gelatins were also extracted from frozen skins for this study. Water vapor permeability of cast alone gelatin films was determined using the standardized gravimetric method. Molecular weight distribution, amino acid composition, gel strength, viscoelastic properties, pH and clarity were also determined for each gelatin. Water vapor permeability of warm and cold water fish gelatin films was 0.8 g.mm/m2.h.kPa and significantly lower than mammalian fish gelatin films (1.9 g.mm/m2.h.kPa) at 25°C, 0/80 %RH through 0.04 mm thickness films. This is related to its highest hydrophobicity due to reduced amount of proline and hydroxyproline in fish gelatins. As expected, gel strength and gel setting temperatures were lower for cold water fish gelatin than for warm water fish gelatins and mammalian gelatins as related to different polypeptide coils molecular weight distribution and amino acid composition. This study demonstrated significant differences in physical, chemical and rheological properties between mammalian and fish gelatins. Lower water vapor permeability of fish gelatin films can be useful particularly for applications related to reduce water loss in cold or frozen foods. |