Coagulated protein obtained by alkali extraction and acid precipitation from the bone containing residues discarded after mechanical separation of chicken was textured by freezing in semi-infinite cylinders followed by heat-setting in a microwave oven. Macrophotography was used to illustrate textural differences resulting from pH variations (4.5-6.0) in the precipitated protein, and changes in the ambient temperature used for freezing (-5°C to -32°C). Well identified, permanent fibres were fanned by the process under all conditions studied. The thickness of the fibres decreased and their radial orientation increased with increasing pH and decreasing ambient temperature of freezing. Cross-linkages between parallel fibres of the main fibre structure were observed primarily as a function of pH, high pH samples showing the highest tendency for formation of these cross-links.
Lawrence, R. A. and Jelen, P.
"Freeze-Induced Fibre Formation in Protein Extracts from Residues of Mechanically Separated Poultry,"
Food Structure: Vol. 1
, Article 10.
Available at: http://digitalcommons.usu.edu/foodmicrostructure/vol1/iss1/10