Flavor thresholds

All aldehydes increased during storage (Fig. 3), but none exceeded their flavor threshold (Fig. 4). 

Strecker aldehydes (Figs. 3 and 4). All 5 aldehydes increased during storage, but none exceeded more than 4.3% of their respective flavor thresholds. 

Furfural (a heat exposure indicator). This aldehyde increased more than 2-fold but reached only 1% of its flavor threshold. 

The increase after 12 weeks for most aldehydes was significant (16-fold for furfural, 7-fold for 2-methylpropanal) however, no aldehyde approached its respective flavor threshold. 

None reached more than 4.3% of their flavor threshold. 

Goal. Using a newly optimized derivatization and solid-phase microextraction (SPME) process, low-level aldehyde concentrations in beer stored for 4, 8, and 12 weeks at 30 °C were monitored. Although all aldehydes increased in concentration, no aldehyde exceeded its flavor threshold. (126 words)... 

None of the analyzed aldehydes exceed their flavor threshold in beer. (Adapted from Vesely et ah, 2003)... 

The intensity of undesirable sensory notes has been positively correlated with the content of carbonyl compounds formed through lipid autoxidation reactions. In general, the carbonyl compounds present have the greatest impact on flavor owing to their low flavor thresholds in comparison with hydrocarbons, substituted furans, and alcohols. Aldehydes are major contributors to the loss of desirable flavor in meats because of their rate of formation during lipid oxidation and low flavor threshold. Thus, an alternative approach for monitoring the extent of lipid oxidation in fats and oils is to measure... 

Flavor threshold in beer. b Flavor threshold in whiskey. 

Effect of Nonvolatile Juice Components on Individual Flavor Thresholds... 

Interaction of volatile and nonvolatile constituents in foods results in flavor modifications of varying intensities. The effects of 5 -nucleotides on the flavor threshold of octanal (23) and the effects of acid, sugar, and pectin on the flavor threshold of limonene (24) have been studied in orange juice. 

Keith, E. S. Powers, J. J. Determination of flavor threshold levels and subthreshold, additive and concentration effects. J. Food Sci., 1968, 33, 213-218. 

Schinneller, D. J. Dougherty, R. H. Biggs, R. H. Influence of selected 5 -nucleotides on flavor threshold of octanal. 

Ahmed, E. M. Dennison, R. A. Dougherty, R. H. Shaw, P. E. Effect of nonvolatile orange juice components, acid, sugar and pectin on the flavor threshold of d limonene in water. 

F = Flavor threshold value, i.e. odor and taste together. 

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