Influence of composition and texture on in-mouth sodium release and saltiness perception during consumption of semi-hard cheeses

Sodium content in human diet being excessive in many industrialized country, health authorities recommended its progressive reduction in food products in order both to improve public health and to decrease health cost (1). Cheese is one of the most important sodium vectors. However, salt (NaCl) is not only responsible for saltiness but is also implied in other functionalities such as flavour enhancement, texture, preservation (2). Keeping a good acceptability of food by the consumer at lower sodium chloride concentration is a real challenge for cheese industry to avoid negative consequences. To reach this goal, it is necessary to understand the role of cheese structure and composition on the release and perception of salt. The objective of this study is to determine to what extent cheese composition and texture influence the release of sodium and the saltiness perception during eating, taking into account the oral behaviour of consumers. Semi-hard cheeses varying in composition (Fat in dry matter, water content in defatted cheese, calcium in defatted dry matter, salt content) were made according to an experimental design. The cheeses were characterized by a conventional sensory profile (taste, texture and global aroma intensity), composition parameters and rheological properties (uniaxial compression at constant displacement rate). Then, both temporal sodium release and temporal saltiness intensities were simultaneously evaluated for each cheese. Important differences were observed between cheeses for both rheological properties and sensory characteristics in term of saltiness and texture. Several significant effects were observed on the increasing phase and at the maximum of the sodium release and on saltiness time intensity curves according to cheese composition / texture. For example, the in-mouth maximum concentration of sodium and the maximum saltiness intensity decreased when fat content increased. These results will be discussed and compared to results obtained with the same approach on model lipoprotein matrices.