Capillarity proposed as the predominant mechanism of water and fat stabilization in cooked comminuted meat batters

Fat- and nonfat-containing meat gels structurally became coarser and porous by partial substitution of whey protein isolate for myofibrillar protein, creating a weaker texture plus greater cook loss (CL: fat + water) and expressible water (EW). Microstructure examinations revealed a tendency for fat to coalesce during cooking of the more coarse-structured gels. This tendency was unaffected by fat pre-emulsification prior to addition, arguing against a strong role of an interfacial protein film in stabilizing fat. Instead, a gel structure with evenly distributed small pores leads to lower CL and EW, thus controlling both water- and fat- holding since fat cannot readily permeate small water-filled hydrophilic pores. Only when large pores or continuous fissures are structurally present can water be released, allowing liquid fat to also migrate and coalesce. This changes the current paradigm of understanding regarding the mechanism of fat/water-holding in comminuted meat products: gel capillarity (gel structure), not fat emulsifying ability of protein, is the likely determining factor. (C) 2015 Elsevier Ltd. All rights reserved.