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Generic Emmental cheese from Germany, produced in five different dairies, was evaluated in terms of thermo-physical properties (melting, flowing, oiling-off and browning) with the aim of characterising German Emmental cheese and identifying similarities and/or differences between Emmental samples from different producers. The data set was subjected to principal component analysis and three principal components were calculated accounting for 68.9% of total variance, indicating that thermo-physical properties are very suitable for Emmental cheese characterisation. Furthermore, linear discriminant analysis was conducted to classify the Emmental cheeses according to the producing dairy based on similarities and/or differences of the thermo-physical properties. Linear discriminant analysis revealed a correct classification of 62.2%. The results offer cheese producers the possibility of varying the manufacturing process and producing similar products with the aim of promoting geographical identification or products with greater differentiating attributes, to enhance distinctiveness of each producing dairy. [ABSTRACT FROM AUTHOR]

The overall aroma profiles of commercial dried sage differ significantly from the profile of macerated fresh leaves. To clarify changes in the key aroma compounds, first an aroma extract dilution analysis was applied on an extract/distillate prepared from the fresh leaves of Italian garden sage cultivated in a green house in Germany. Among the 39 aroma active compounds characterized, ( Z )-3-hexenal, 1,8-cineol, borneol and eugenol showed the highest flavor dilution (FD) factors. Odorants identified with FD factors between 64 and 8192 were quantitated to calculate odor activity values (OAV; ratio of concentration to odor threshold). The highest OAVs were determined for myrcene, ( Z )-3-hexenal, (1S,2R,4S)-borneol and 1,8-cineol. A mixture of 22 key reference aroma compounds in the same concentrations as determined in the fresh sage leaves successfully mimicked the overall aroma profile of the spice. To get insight into changes induced by drying, all key aroma compounds were quantitated in sage leaves from the same plant by drying at 50 °C. While all monoterpenes remained nearly unchanged during drying, in particular highly volatile compounds such as dimethyl sulfide or 2- and 3-methylbutanal were decreased. Almost a total loss occurred for 3-(methylthio)propanal, phenylacetaldehyde, and ( Z )-3-hexenal. By contrast, storage of the dried leaves for 12 months at room temperature in the dark did not much effect the concentrations of selected key odorants, thus indicating that drying is the most important factor for the changes in aroma compounds. Sensory profiling of six commercial sage samples showed different aroma profiles, which also clearly differed from the profile of the sage dried in lab scale, which was rated to elicit the most typical sage aroma. In addition, the concentrations of selected key aroma compounds as well as the total amount of volatiles were clearly lower in all commercial samples.

Application of aroma extract dilution analysis on the volatiles isolated from a Bavarian Pilsner-type beer revealed 40 odor-active constituents in the flavor dilution (FD) factor range of 16-2048, among which ethyl octanoate, (E)-beta-damascenone, 2- and 3-methylbutanoic acid, and 4-hydroxy-2,5-dimethyl-3(2H)-furanone showed the highest FD factor of 2048. After quantitation of the 26 odorants showing FD factors > or =128 by stable isotope dilution analysis and determination of their odor thresholds in water, odor acitivity values (OAVs) were calculated. The results indicated ethanol, (E)-beta-damascenone, (R)-linalool, acetaldehyde, and ethyl butanoate with the highest OAVs, followed by ethyl 2-methylpropanoate and ethyl 4-methylpentanoate, which was previously unknown in beer. Finally, the overall aroma of the beer could be mimicked for the first time by recombining 22 reference odorants in the same concentrations as they occurred in the beer using ethanol/water as the matrix.