Flavor-matrix interaction

This paper reviews the interactions between aroma compounds and other components of a wine matrix colloids, fining agents and ethanol. Studies are carried out with model systems and instrumental methods to investigate flavor-matrix interactions. 

The knowledge of the composition of volatile compounds in food has greatly increased during the past decade. Many studies continue to report the identity and the concentration of volatile compounds in food matrices. However concentration alone appears insufScient to explain flavor properties of food. The lack of our knowledge concerning the influence of non-volatile constituents of food on the perception of aroma has to be filled by studies such as those presented in this paper. Data on interactions between aroma and matrix in wine are scarce compared with other food matrices studied. Flavor-matrix interactions in wine have generally been obtained in model systems and with instrumental experiments. However it is possible to develop some hypotheses on the possible sensory contribution of some non-volatile compounds of wine on overall aroma. 

Analytical methods involving exhaustive extraction of flavor compounds (i.e., liquid/liquid extraction, dynamic headspace) do not take these matrix effects into account. However, new instrumentation and methodologies are yielding improved information on the mechanisms involved in flavor/matrix interactions and the effects on flavor perception. For example, spectroscopic techniques, such as nuclear magnetic resonance (NMR), can provide information on complex formation as a function of chemical environment and have been used to study both intra- and intermolecular interactions in model systems [28,31]. In addition, NMR techniques, initially developed to study ligand binding for biological and pharmaceutical applications, were applied in 2002 to model food systems to screen flavor mixtures and identify those compounds that will bind to macromolecules such as proteins and tannins [32]. Flavor release in the mouth can be simulated with analytical tools such as the retronasal aroma simulator (RAS) developed by Roberts and Acree [33]. These release cells can provide... 

In Eq. (37) soft external and a fields, carrying momentum q p l. were assumed. Then, they are present inside of the form-factor F in above mentioned form. If v, a external fields are flavor matrices then form-factor F also becomes matrix Nf x Nf. So, we get the partition function Z[m,V], where W are multi-quark interaction terms in the presence of current quark mass m and external fields V. 

Here To = y 11/ is proportional to the unit matrix in flavor space. The quark field ip now contains a third component in flavor space, the strange quark, and consequently the mass matrix rh, see Eq. (4), is equally enlarged by the current strange quark mass, ms, which can in general be different from up and down quark masses. This interaction consists of a U(3)l x U(3)ft-syrnmetric 4-point interaction and a 7 Hooft-type 6-point interaction which breaks the UA (1) symmetry. 

An(p) must be a symmetric matrix in the spaces of internal degrees of freedom. Taking into account the property that the most attractive channel of the OGE interaction is the color antisymmetric 3 state, it must be in the flavor singlet state. 

Alginates, unique hydrocolloids extracted from selected species of brown seaweed (kelp), interact with calcium ions to produce thermally stable gels. Using this interaction, flavor oils may be encapsulated or entrapped in the algin gel matrix. Encapsulation is accomplished at ambient temperatures. Products may be used "as is" (wet) or subsequently dried. This technique offers the potential for novel flavor effects, flavor protection, and new food products. 

Milling results in particle size reduction. Milling techniques have long been used for size reduction of pharmaceutical powders to improve body absorption (Bentham et al, 2004). An increased surface area of food materials will increase the rate of water absorption of materials, improve solubility of dry products, and increase accessibility of sites for chemical reactions (e.g., oxidation, digestion, flavor release, catalyst, and enzyme activity). The structure of food is also important as it dictates how, when, and where food nutrients and flavors may be released. The effectiveness of nutrient bioavailability in food is in part related to its size although other factors such as interactions of the component with a matrix also influence how the component is released. 

Bakker, J., Flavor interactions with the food matrix and their effects on perception, in Ingredient Interactions Effects on Food Quality, Goankar, A.G., Ed., Marcel Dekker Inc., New York, 1995, p. 411. 

The rancid lipid odor profile is made up of a mixture of several volatile compounds. Among them, the trans, cw-alkadienals, and vinyl ketones have the lowest flavor threshold in oils, while the threshold of hydrocarbons (alkanes and alkenes) is the highest (Min, 1998). The sensory effects depend on the composition of the participating compounds and on the composition of the food matrix, while the rancid off-odors and off-flavors of foods emanate from the interactions between lipids and other components, especially proteins. 

This approach was obviously nonphysical in its one-at-a-time interaction scheme. A second variant on this uses a state transition matrix approach similar in flavor to methods described by Koza.i This approach uses the distance matrix D,-, whose elements are the distance between atoms i and /. At each step, a new distance matrix D,y is formed for which D-y = + Sjj, where S... 

In strong and electromagnetic interactions, hadronic flavor is conserved, i.e. the conversion of a quark of one flavor (d, u, s, c, 6, t) into a quark of another flavor is forbidden. In the Standard Model, the weak interactions violate these conservation laws in a manner described by the Cabibbo-Kobayashi-Maskawa mixing (see the section Cabibbo-Kobayashi-Maskawa Mixing Matrix ). The way in which these conservation laws are violated is tested as follows ... 

The structure of the food matrix is also known to affect the release of volatile compounds having an impact on flavors and aroma. Changes in flavor result from the interactions of lipid-derived carbonyl compounds by aldolization with the amino groups of proteins. Undesirable flavors are produced when beef or chicken are fried in oxidized fats by the interaction of secondary lipid oxidation... 

One can also conceive of interactions that favor the release of flavor snbstances. The most obvions is the salting ont of a flavor componnd from solntion. In this case, the flavorant is pnshed ont of the food matrix into the oral cavity, enhancing perception. Another example is the evaporation of CO2 or ethanol from a food that may carry aroma componnds thereby enhancing aroma release. 

Of the food matrix flavor interactions, the effect of fat/oil on flavor release is most understandable and thus predictable. In the case of fat/flavor interactions, the overriding effect is the role fat plays as a flavor solvent. Unlike carbohydrates or proteins where numerous undeflnable chemical interactions come into play, fat has little true chemical interaction, and thus its effect on flavor release is largely quantifiable. (The discussion that follows will look very much like that provided in Chapter 3 where partition coefficients in solvent extraction [and headspace methods] were discussed.)... 

A second area requiring further study is that of the dynamic nature of flavor release in complex food and beverage matrices. There is an increasing understanding that aroma perception is dynamic and that interactions between volatile compounds and matrix components can have a significant impact on flavor volatility and flavor release (reviewed in [22,23]). For example, in wine, ethanol can suppress the volatility of esters so that perception of fruitiness is decreased [24,25]. Similarly, polyphenols, important nonvolatile constituents of red wine in particular, may interact with some flavor compounds, to alter their volatility and flavor release [26-31]. However, the mechanisms of these interactions and their effects on sensory perception are not yet fully characterized. 

As a research tool, the multiple-channel flavor delivery system (McFlads) offers many opportunities for study. Presentation of flavor stimuli in solution is, of course, a simplification of many eating experiences (because of the absence of food matrix and the mastication required to break it down). However, this simplification facilitates the study of fundamental interactions among the senses, without variations caused by mastication. McFlads allows the delivery of multiple stimuli in-mouth in a temporally controlled fashion and results in retronasal aroma delivery, which is representative of human ingestion. Taste, aroma, and tactile stimuli (e.g., viscous liquids) can be presented in this fashion. 

Interactions between flavor compounds and a variety of nonflavor matrix components, for example, protein and fat, influence flavor perception in foods. 

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