Cheeses taste perception

The objective of this paper is to bring together original results on flavor release of soft cheese obtained over tiie last few years. First, results about the evolution of cheese taste during ripening are presented. The effect of the cheese matrbc on the evolution of taste-active compounds of the WSE are described. The second part deals with attempts to relate taste- and aroma release parameters with perception parameters in a range of cheeses. 

Bitter peptides have been identified in hydrolyzates of casein (12,13), cheese (13a,b), and soy bean (14,15,15a). The bitter taste has been related to the hydrophobic amino acid content (16-20) and to chain length. Ney and Retzlaff (21) established a formula relating the bitterness of peptides to their amino acid composition and chain length. Too large a proportion of hydro-phobic amino acids gives rise to bitterness yet above a certain molecular weight, bitterness is not perceptible even when there are hydrophobic amino acids (21). Peptides that were responsible for bitterness in Cheddar cheese were rich in Pro, which occurred predominantly in the penultimate position (21a). 

Formation, Release, and Perception of Taste and Aroma Compounds from Cheeses as a Function of Matrix Properties... 

This part concerned attempts to relate taste- and aroma release parameters with perception parameters from a complex matrix such as soft cheeses. 

This acid has a particularly pungent and acrid odor reminiscent of Roquefort cheese and of other cheeses. The taste is acrid-acid but becomes fruity-sour below 10 ppm (Arctander, 1967). By GC-olfactometry, the odor perception, in the evaluation of the aroma of a roasted Columbian coffee, is sweaty, fermented together with the 3-methyl isomer, the contribution to coffee flavor is very important (Holscher et al., 1990). In the aroma of a green coffee, it is described as weak, fermented (Holscher and Steinhart, 1995). Karl et al. (1992) showed that the enantiomers have different odors, the (R)-isomer being cheesy and the (5)-isomer fruity. 

Taste compounds, which may elicit acid, sweet, salty or bitter tastes, must pass into the aqueous phase before they are sensed by the taste receptors in the mouth. The aqueous phase is composed of the water from the food mixed with saliva in the mouth. Thus, factors such as water solubility, pH and salt formation, which influence the partitioning of taste compounds between aqueous and fat phases, influence flavour perception. For example, the presence of fat may retard their passage into saliva and thus limit the perception of taste. The way in which fat and water are distributed in a food, and the proportions of each, influence flavour perception. Many foods have a poor flavour if they contain too little fat (cheese is a good example). The effect, while very obvious to the consumer, is not fully understood scientifically but may be related to the state of dispersion of the fat. 

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