Flavour and Fragrance Journal

Nineteen volatile sulphur compounds, VSC's, including ten thioesters and eight alkyl sulphides, were quantified using SPME-GC-pulsed flame photometric detection, PFPD, in twelve Florida strawberry cultivars. The major headspace VSCs in all 12 cultivars were methanethiol and methyl thioacetate, together comprising 77 to 95% of the total VSCs. Concentrations for the 13 major strawberry VSCs were determined at five maturity stages. Pureed fruit produced 10-20 times higher headspace volatiles than intact berries.

Inquiry of the metabolisation of 1,8-Cineole in an intestinal cell culture model and acquisition of its immune-modulatory effect via gene expression analysis.

In vivo aroma release was studied on 44 subjects who freely consumed six processed model cheeses flavoured with the same concentration of nonan-2-one and ethyl propanoate. An increase in firmness induced an increase in chewing duration, amount of saliva incorporated into the food bolus, total amount of aroma released and rate of release. A higher fat content led to a lower amount of nonan-2-one released and a longer persistence of nonan-2-one in the breath.

The volatile odorant fraction of aromatic caramel was investigated using GC/O and GC/MS analyses. Forty nine aroma compounds were identified, some of them being reported for the first time in caramel. Sensory properties were also evaluated by establishment of descriptive profiles. The relationship between the sensory properties and the GC/O data was modeled by Partial Least Square regression (PLS-R). Heterocyclic compounds, carbocyclic compounds and carboxylic acids appeared to be the main contributors to the caramel odorant properties.

In this study the effects of food matrix structure and composition on real-time aroma release during the consumption of food were systematically characterised using proton transfer reaction mass spectrometry (PTR-MS) and a panel of human subjects. Everyday foods representing a range of liquid, semi-solid and solid states, and varying in texture and composition (fat content) were selected. Target volatiles released during eating were measured in exhaled nostril air and the corresponding sensory stimulus was rated using continuous time intensity (TI). The data provided objective insights into the relationship between food structure and composition and volatile release; application of this approach may help guide the development of novel food products.

Molecular modelling approaches (pharmacophore, docking and molecular dynamics) are compared to biophysical data (fluorescence spectroscopy). We examine the predictive capabilities of modelling techniques to reproduce the ranking between weak, medium and good odorants for an odorant binding protein.

Both Maillard- and fermentation-derived compounds were identified as potential chemical markers to predict bitterness of whole-wheat bread. Highly significant correlations (α = 0.01) were observed between the perceived bitterness in the crust and the quantity of 5-(hydroxymethyl)furfural (r² = 0.93) and 2,3-dihydro-3,5-dihydroxy-6-methyl-4(H)-pyran-4-one r² = 0.95). In the crumb, the bitterness was correlated with the amount of l-tryptophan (r² = 0.91).