Flavor Release from Foods

Historically there have been numerous studies on how aroma components interact with the major food constituents. One speaks of interactions since any type of interaction between a flavor compound and a food constituent that restricts the movement of a flavor stimulus to a sensory receptor influences perception. This interaction may be chanical (e.g., hydrogen, hydrophobic, ionic, or covalent bonding), e.g., a chemical interaction may reduce the vapor pressure of an aroma substance thereby reducing the driving force for its evaporation in the oral cavity and reducing its movement to the olfactory receptors. 

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. 

None of the scenarios described above wonld be particnlarly problematic to the flavor of a food if the effects described operated across all aroma components equally. If this were the situation, then one would simply add more or less flavoring to a food depending upon the overall balance of promotion vs. inhibition factors. Unfortunately, 

This phenomenon affects the inventory of flavor companies. A typical flavor company may have several hundred different strawberry flavors, for example. This is not necessarily because the customer has hundreds of concepts of strawberry flavor to be met, but that a flavor must be designed to undergo a multitude of interactions with the food and ultimately provide a release profile that is liked by the consumer. This phenomenon is also obvious in the recent low-fat food trend. Unquestionably, this concept has been a failure since food companies could not deliver a low-fat product to the customer that had a satisfactory sensory profile. Commonly, people would try a low-fat version of a food product once but then never buy it again. The low-fat and normal-fat products generally used the same flavor system, but they released flavor differently due to formulation variations. These variations may have altered chemical or physical interactions thereby altering the flavor release profile. 

In this chapter we will provide a broad overview of the flavor interactions that may occur in foods considering how flavors interaction with nonvolatiles in foods [6]. Initially the interaction of flavorings with the major food constituents (e.g., lipid, carbohydrates, and proteins) will be discussed. The final section will include some discussion of interactions with minor constituents (e.g., melanoidins, polyphenolics, and high potency sweeteners) as literature permits. The reader is encouraged to go to more detailed reviews included in books edited by Taylor [ 1 ] or symposia proceedings such as Roberts and Taylor [3], Schieberle and Engel [4], Teranishi et al. [2], or Taylor and Mottram [5]. 

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Lee, W.E. 111. 1986. A suggested instrumental technique for studying dynamic flavor release from food products. 7. Food Sci. 51 249-250. 

The broad diversity in functionality of carbohydrates also offers substantial opportunity for than to influence the mass transport of flavorants. Their ability to form gels, impart viscosity, or promote emulsion formation in food systems are all factors that influence mass transport (dynamic release during eating) of odorants during eating. This section of this chapter will provide an overview of how carbohydrates will influence flavor release from foods. Discussion is organized by carbohydrate type. 

We will likely have better success understanding/piedicting the effects of food rheology on aroma release than chemical interactions. Mass transfer is a mature science whose principles can be directly applied to our task. Yet, the rheological properties of a food can be extremely complex and thus be problematic as well. Unfortunately, flavor release from foods is only beginning to be understood — substantial work remains to be done before science will guide this aspect of flavor development. 

AJ Taylor. Volatile flavor release from foods During eating. CRC Crit Rev Food Sci Nutr 36 765-784, 1996. 

KB de Roos. Physicochemical models of flavor release from foods. In DD Roberts, AJ Taylor, eds. Flavor Release. Washington, DC American Chemical Society, 2000, pp 126-141. 

Bylaite, E., Adler-Nissen, J., and Meyer, A.S. Effect of xanthan on flavor release from thickened viscous food model systems, J. Agric. Food Chem., 53(9) 3577-3583, 2005. 

Springett, M.B., Rozier, V., and Bakker, J. 1999. Use of fiber interface direct mass spectrometry for the determination of volatile flavor release from model food systems. J. Agric. Food Chem. 47 1123-1131. 

Reineccius TA, Reineccius GA, Peppard TL. 2003. Flavor release from cyclodextrin complexes Comparison of alpha, beta, and gamma types. Journal of Food Science 68(4) 1234-1239. 

Yoshii H, Soottitantawat A, Liu X-D, Atarashi T, Furuta T, Aishima S, Ohgawara M, Linko P. 2001. Flavor release from spray-dried maltodextrin/gum arabic or soy matrices as a function of storage relative humidity. Innovative Food Science and Emerging Technologies 2 55-61. 

This second edition offers new material on methods of sensory detection (nasal through the nose) or (retronasal through the mouth and back of the oral cavity), different flavor release phenomena in the headspace versus the mouth, and matrix in flavor release from oils compared to emulsion systems. Advanced gas chromatographic methods are included, such as solid phase microextraction for the volatile analyses in foods and vegetable oils, gas chromatography-olfactometry, and aroma extraction dilution analyses. 

The respective kinetics correlates with and can be predicted from the glass transition temperature of the carrier materials. Plasticization by water absorption under conditions of high humidity may cause reduction of the glass transition temperature below room temperature. Then, the structural change in the wall material leads to collapse of the food powder, resulting in flavor release from the rubber state of the carrier matrices (Ubbink and Schoonman, 2003). 

Harrison, M., B.P Hills, J. Bakker, T. Clothier, Mathematical models of flavor release from liquid emulsions, J. Food Sci., 62(4), p. 653, 1997. 

Nahon, D.F., PA. Navarro y Koren, J.P. Roozen, M.A. Posthumus, Flavor release from mixtures of sodium cyclamate, sucrose, and an orange aroma, J. Agric. Food... 

Reineccius, T.A., G.A. Reineccius, T.L. Peppard, Comparison of flavor release from alpha- beta- and gamma-cyclodextrins, J. Food Sci., 68(4), p. 1234, 2003. 

JX Guinard, C Marty. Time-intensity measurement of flavor release from a model gel system Effect of gelling agent type and concentration. J Food Sci 60 727-730, 1995. 

Interactions of flavor compounds with proteins are known to have a strong influence on flavor release from model foods [1], Proteins often cause a decrease in the volatility of flavor compounds. It is well known that proteins interact with volatiles both reversibly [2-3] and irreversibly [4-5]. 

M Harrison. Effect of breathing and saliva flow on flavor release from liquid foods. J Agric Food Chem 46 2727-2735, 1998. 

Ting, V. J. L., Soukoulis, C., Silcock, P. et al. (2012) In vitro and in vivo flavor release from intact and fresh-cut apple in relation with genetic, textural, and physicochemical parameters. J. Food Sci. 77, 1226. 

R. Linforth, K. Ingham, and A. Taylor, Time course profiling of volatile release from foods during the eating process. Flavor Science Recent Developments (A. Taylor and D. Mottram, eds.). The Royal Society of Chemistry, Cambridge, UK, 1996, pp. 361-368. 

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