Tinkturenpresse

Triticum aestivum L. syn. Triticum vulgare Vill. - Poaceae - common wheat, bread wheat, (Weich-)Weizen, Brotweizen

„…a cultivated wheat species. About 95% of wheat produced worldwide is common wheat; it is the most widely grown of all crops and the cereal with the highest monetary yield.“ https://en.wikipedia.org/wiki/Common_wheat

Wheat flour is a powder made from the grinding of wheat used for human consumption. Whole-wheat flour is used in baking of breads and other baked goods; Whole grain flour contains the whole grain, including bran, germ and endosperm, but not the chaff.

„An investigation on the odor-active compounds of wholemeal (WWF) and white wheat flour (WF 550) by aroma extract dilution analysis (AEDA) and by quantitative studies using stable isotope dilution assays (SIDA) revealed a significant number of odor-active compounds, such as (E)-2-nonenal, (E,Z)- and (E,E)-2,4-decadienal, (E)-4,5-epoxy-(E)-2-decenal, 3-hydroxy-4,5-dimethyl-2(5H)-furanone, and vanillin, with high odor activities in both wheat flours. The amounts and, consequently, the aroma potencies of vanillin, (E,E)-2,4-decadienal, and 3-(methylthio)propanal were much higher in the WWF than in the WF 550 samples. Fermentation of suspensions of both flours with lactic acid bacteria did not generate new odorants; however, many compounds, such as acetic acid or 3-methylbutanal, were increased, whereas aldehydes (formed from the degradation of unsaturated fatty acids) were decreased. Comparing the odorant concentrations present before and after fermentation gave evidence that the main influence of the microorganisms on sourdough aroma is to either enhance or decrease specific volatiles already present in the flour. A comparison with literature data indicated that most of these odorants are also important for the bread crumb aroma present after baking of the dough.“
Amounts (µg/kg) of odorants in wholemeal flour e.g.: 3-methylbutanal (155), 2-methylbutanal (75), 2-/3-methylbutanoic acid (630), methional (125), hexanal (11200), (Z)-4-heptenal (20), (E)-2-nonenal (260), (E,Z)-2,6-nonadienal (65), (E,Z)-2,4-decadienal (1810), (E,E)-2,4-decadienal (1690), acetic acid (218000), butanoic acid (9000), pentanoic acid (11600), vanillin (2910).
[Czerny, Michael, and Peter Schieberle. „Important aroma compounds in freshly ground wholemeal and white wheat flour identification and quantitative changes during sourdough fermentation.“ Journal of Agricultural and Food Chemistry 50.23 (2002): 6835-6840]

„The aroma of sourdough bread is influenced by odorants present in the flour (Czerny and Schieberle, 2002), by the generation of aroma compounds and their precursors by microorganisms and flour enzymes during fermentation, and by removal of odorants during fermentation and baking (reviewed by Hansen and Schieberle, 2005). Thermal processes during baking are particularly important for odorant generation in the crust (Schieberle, 1990), whereas the flavour of the bread crumb is mainly determined by compounds generated during fermentation (Gassenmeier and Schieberle, 1995). Furthermore, the choice of wheat flour type affects the bread aroma… Since (E,E)-2,4-decadienal and (E)-2-nonenal are key aroma compounds in the wheat bread crumb, the fate of these compounds during fermentation will have a strong influence on the flavour of the bread.“
[Vermeulen, Nicoline, et al. „Reduction of (E)-2-nonenal and (E,E)-2,4-decadienal during sourdough fermentation.“ Journal of Cereal Science 45.1 (2007): 78-87]

„Slices of wheat bread were toasted until a distinct intensity of brown colour. Potent odorants formed were evaluated by aroma extract dilution analysis and gas chromatography/olfactometry of headspace samples. Compouns showing high dilution factors were quantified, and their aroma activity values (OAV, ratio of concentration to odour threshold) were calculated on the basis of odour thresholds in starch. The roasty smelling 2-acetyl-1-pyrroline (I), showed the highest OAV followed by (E)-2-nonenal (II), 3-methylbutyric acid (III), 4-hydroxy-2,5-dimethyl-3(2H)-furanone (IV), methional (V), and 2,3-butanedione. Formation of nine odorants (I to V among others) was measured in relation to the intensity of the brown colour. It was found that at the beginning of toasting (I) increased mor rapidly in the bread slices than (IV) which was mainly produced at medium browning.“
[Rychlik, Michael, and Werner Grosch. „Identification and quantification of potent odorants formed by toasting of wheat bread.“ LWT-Food Science and Technology 29.5-6 (1996): 515-525]

The most intensive odor impressions of distiller’s grains (DG) from wheat are seasoninglike, roasty/breadlike, and malty/caramellike. Among 24 of the 42 odor-active compounds obtained by solvent-assisted flavor evaporation (SAFE), 3-hydroxy-4,5-dimethyl-2(5H)-furanone (seasoninglike) showed the highest flavor dilution (FD) factor, and 7 compounds (3-methylbutanoic acid, dimethyl trisulfide, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 2-ethyl-3,5-dimethylpyrazine, 2-phenylethanol, 2,6-nonadienal, and 5-ethyl-3-hydroxy-4-methyl-2(5H)-furanone) with a FD factor ≥ 32 were identified as key aroma compounds in DG from wheat.
[Roth, M., et al. „Characterization of key aroma compounds in distiller’s grains from wheat as a basis for utilization in the food industry.“ Journal of agricultural and food chemistry 62.45 (2014): 10873-10880]

Triticum aestivum s. lat., Oberlaa, Österreich © Rolf Marschner (2011) www.botanische-spaziergaenge.at