Publication no. C-2001-0608-02R |  VIEW ARTICLE

Influence of Sodium Caseinate and Whey Protein on Baking Properties and Rheology of Frozen Dough.

S. Kenny (1), K. Wehrle (1), M. Auty (2), and E. K. Arendt (1,3). (1) Department of Food Technology and National Food Biotechnology Centre, University College Cork, National University of Ireland. (2) Teagasc Dairy Products Research Centre, Fermoy, Co. Cork, Ireland. (3) Corresponding author. Phone: +353-21-4902064. Fax: +353-21-270213. E-mail: <e.arendt@ucc.ie> Cereal Chem. 78(4):458-463. Accepted March 15, 2001. Copyright 2001 American Association of Cereal Chemists, Inc.

Dairy ingredients are added to bakery products to increase nutritional and functional properties. Sodium caseinate (SC) and whey protein concentrate (WPC) were incorporated into frozen dough. WPC was subjected to heat treatment (WPCHT) to eliminate undesirable weakening of the gluten network. 2% SC or 4% SC decreased proof time, increased loaf volume, and improved texture. Effects of adding 4% SC on baking quality were similar to adding ascorbic acid (AA) and diacetyl tartaric acid esters of monoglycerides (DATEM). WPC increased proof time, decreased volume, and negatively affected texture. Heat treatment of WPC improved baking performance. Bread with WPCHT had volume similar to that of the control without dairy ingredients. Adding 4% SC decreased resistance to extension (R(5cm) measured with the extensigraph), while adding 4% WPC increased extensibility. Dynamic oscillation testing determined the effects of the ingredients on fundamental rheological properties. WPC decreased storage modulus (G(prime)) and loss modulus (G(double prime)), while heat treatment of WPC increased G(prime) and G(double prime). Confocal laser scanning microscopy (CLSM) showed that milk proteins affect frozen dough ultrastructure. Frozen doughs with SC had an enhanced gluten network compared with the control, while untreated WPC appeared to interfere with the gluten network.