Rubbery flavor

Pungent, musty odors Rio, medicinal, phenolic, or iodine-like flavor Musty cork flavor Iodoform taint Oxidized oil, waxy, rubbery... 

Bullens, 1994 Anonymous, 1996). Textural defects include increased firmness, rubberiness, elasticity, hardness, dryness, and graininess. The negative flavor attributes of reduced-fat Cheddar include bitterness (Ardo and Mansson, 1990) and a low intensity of typical Cheddar cheese aroma and flavor (Banks et al., 1989 Jameson, 1990). Approaches used to improve the quality of reduced-fat cheese include ... 

One of the major problems encountered in maximizing the flavor yields from cysteine-sugar systems is the high instability of the thiols diat are generated. The thiols do not only react with melanoidins but also widi each other (6, 2S). The result is that the characteristic meaty flavor disappears and a rubbery off-flavor is formed. Since the rates of the second-order reactions between the thiols are proportional to the square of the thiol concentrations, it is clear that products... 

Accurate description of barrier films and complex barrier structures, of course, requires information about the composition and partial pressure dependence of penetrant permeabilities in each of the constituent materials in the barrier structure. As illustrated in Fig. 2 (a-d), depending upon the penetrant and polymer considered, the permeability may be a function of the partial pressure of the penetrant in contact with the barrier layer (15). For gases at low and intermediate pressures, behaviors shown in Fig. 2a-c are most common. The constant permeability in Fig.2a is seen for many fixed gases in rubbery polymers, while the response in Fig. 2b is typical of a simple plasticizing response for a more soluble penetrant in a rubbery polymer. Polyethylene and polypropylene containers are expected to show upwardly inflecting permeability responses like that in Fig. 2b as the penetrant activity in a vapor or liquid phase increases for strongly interacting flavor or aroma components such as d-limonene which are present in fruit juices. 

In general, the rotational and vibrational motions are limited in the amorphous glassy state. In the rubbery state, on the other hand, large-scale molecular motion, such as translational motion, is possible (Ubbink and Schoonman, 2003). Therefore, the encapsulated flavors or oils exist stably in the amorphous glassy state, but in the rubbery state some deterioration may take place. Since an amorphous state is not an equilibrium state, a thermodynamic driving force tends to shift the amorphous state to a more stable crystal state, resulting in a time-dependent crystallization, solidification of powders, and caking. 

Figure 1.12 is a schematic illustration of a spray-dried particle in a humid air environment in which the particle would adsorb water vapor this is then followed by state changes of carrier matrices from the amorphous state to a rubbery state. The encapsulated flavors can easily move in the matrix of the carrier matrices. At the same time, the oxygen uptake into the wall matrix becomes higher and the oxidation of the encapsulated flavors progresses. The most interesting point is that around the glass transition temperature, both release and oxidation rate constants change nearly in the same trends with T- T, as shown in Figure 1.11. This implies that the flavor diffusion and the oxygen upt e can be treated as a similar behavior.

The flavor is burnt, rubbery, mouldy, earthy (Chemisis, 1980). 

The odor threshold given by the authors is 0.01 ppb in water, with a cooked-meat aroma from 0.05-0.5 ppb becoming thiamine-like at higher concentrations. At a concentration of 0.3 ppm it has a roasted, meaty, rubbery, burnt flavor (Chemisis, 1996). 

When pure, the product has a very powerful sulfurous odor, but at high dilution it develops a pleasant, grilled, smoky and very characteristic note (Ohloff and Flament, 1979). At a concentration of 1 ppm, it has a rubbery, burnt, sulfury, seafood flavor (Chemisis, 1995). The odor threshold in water is 5ppb (Tressl and Silwar, 1981), perceived as cooked meat with slight coffee note from 10 100 ppb. Tressl (1989) reported a threshold of 0.5ppb with a roast sulfur note at 10-50ppb. 

It was discovered for the first time in a sterilized milk concentrate (Arnold et al., 1966). It has a burnt, phenolic, gassy flavor (Chemisis, 1965). As benzothiazole seems to be met in numerous flavor extracts and as its formation had never been rationalized, Ferretti and Flanagan (1973) were of the opinion that it could be a contaminant from rubber tubing (even with very short connections) and confirmed it with a blank experiment. The authors stated also that benzothiazole could contribute to stale flavor. Maga (1975c) described it as having a quinoline-like, rubbery odor. 

According to the encapsulation processes used, the matrices of encapsulation can show diverse shapes (films, spheres, irregular particles), structures (porous or compact), physical structures (amorphous or crystalline dehydrated solid, rubbery or glassy matrix). This diversity is responsible for the different diffusion of flavors (Madene et al., 2006). 

Figure 6.30 is a schematic picture of a spray-dried particle in a humid air environment, in which the particle can absorb water vapor, followed by a state change of the carrier matrix from amorphous into rubbery. The encapsulated flavor can easily move in the rubbery carrier matrix. At the same time, oxygen uptake into the matrix wall becomes stronger, and oxidation of the encapsulated flavor progresses. Most interestingly, around the glass transition temperature both the release... 

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