Flavor dilution factor

FD factor (Flavor dilution factor) The ratio of concentration of a compound in the initial concentration to that in the most diluted concentration in which the odor could be detected by GCO. 

FIGURE 17.4 FD (flavor dilution) factors of flavor components of green tea drinks due to the heating process. 

Diode Array Detection Flavor Dilution factor... 

Another powerful technique known as aroma extract dilution analysis is used to determine the most significant odor and flavor compounds in a complex mixture in a food product. This method determines the odor activity of volatile compounds in an extract eluted from a high-resolution capillary GC-SP column (see Table 11.9). The odor activity or impact of a compound is expressed as the flavor dilution factor (FD), which is the ratio of its concentration in the initial extract to its concentration in the most dilute extract in which the odor can be detected by GC-SP. However, the information from this technique may be of limited practical value, because it ignores the significant effect of food matrices on flavor and odor perception of mixtures of flavor and odor compounds. Advanced instrumental techniques have been developed for flavor analysis during food consumption. These techniques permitting direct mass spectrometry at atmospheric pressure are discussed in Chapter 6. 

Flavor dilution factor Volatile compound Description... 

From Wagner and Grosch (1997). FD factor = flavor dilution factor, determined on neutral/basic volatiles by gas chromatography-olfactometry after stepwise dilution with diethyl ether. 

Schnermann and Schieberle [54] reported 13 odorants with the highest flavor dilution factors in milk chocolate as 3-methylbutanal (malty) 2-ethyl-3,5-dimetbylpyrazine (potato chip-like) 2- and 3-methylbutanoic acid (sweaty) 5-methyl-(E)-2-hepten-4-one (hazelnut-like) l-octen-3-one (mushroom-Uke) 2-ethyl-3,6-dimethylpyiazine (nutty, earthy) 2,3-diethyl-5-methylpyrazine (potato chip-like) (Z)-2-nonenal (green, tallowy) (E,E)-2,4-decadienal (fatty, waxy) (E,E)-2,4-nonadienal (fatty) 8-decalactone (sweet, peach-like) and 2-methyl-3-(methyldithio)furan. 

These limitations are eliminated by the stepwise dilution of the volatile fraction with solvent, followed by the gas chromatographic/olfactometric analysis of each dilution. The process is continued until no more aroma substance can be detected by GC olfactometry. In this way, a dilution factor 2 (n = number of 1 -b 1 dilutions) is determined for each aroma substance that appears in the gas chromatogram. It is designated as the flavor dilution factor (FD factor) and indicates the number of parts of solvent required to dilute the aroma extract until the aroma value is reduced to one. 

Odorant Odor quality Kovats index (DB-Wax) Flavor dilution factor... 

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