Included Water Phase as Determinant for Perception of Gelled Food Structures

• Published in: Food biophysics Vol. 6; no. 2; pp. 303 - 312
• Main Author: de Jongh, Harmen H. J
• Format: Journal Article
• Language: English
• Published: Boston Boston : Springer US 01.06.2011; Springer US; Springer Nature B.V
• Subjects: Analytical Chemistry; Biological and Medical Physics; Biophysics; Chemistry; Chemistry and Materials Science; deformation; energy; Food chains; Food Science; foods; Gels; Perceptions; polysaccharides; rheological properties; Saccharides; sensory evaluation; Special Issue Article; sweetness; Taste; Water; water activity; Water content; whey protein; Water phase; Gelled products; Sensory mouthfeel; Food microstructure; Taste; Serum release
• ISSN: 1557-1858; 1557-1866
• DOI: 10.1007/s11483-011-9207-2

This work underlines that the role of water, its flow properties and its expulsion from the spatial network during oral processing, cannot be neglected in understanding the relation between gelled food structures and its sensory perception. It is shown that the properties of the included water phase of semi-solids are important as this phase can boost the water content in the oral cavity, and thereby increase taste sensations like sweetness. Moreover, the included water phase also plays a crucial role in how the energy exerted onto the gel during palating is used for either fracture, stored or dissipated in or by the network. To demonstrate this, a series of mixed whey protein/polysaccharide cold-set gels have prepared that were studied for a number of rheological and sensorial properties. Also, information on the expulsed serum volume during uniaxial compression and the breakdown pattern of these gels in the oral cavity was determined. It is shown that expulsion of serum from a gel during oral processing can be substantial and set by the morphology of the formed gel and the stiffness of the matrix. This expulsed serum volume is directly proportional to taste response. Moreover, it is found that both the viscous and elastic flow of serum through the gel upon deformation contribute to the perceived crumbliness of gels by lowering the recoverable energy. The elastic contribution of polysaccharides in the serum impairs with the energy available for fracture during oral processing, thereby affecting the sensory spreadability of the product.