Publications by authors named "Thomas Heymann"

The technology of bread making is characterized by three major steps: dough mixing, proofing, and baking. To follow the course of Maillard processes in an authentic food matrix, the complete manufacturing process of wheat bread rolls was assessed along all production steps with the quantitation of sugars, furfurals, 1,2-dicarbonyl compounds, and advanced glycation end products (AGEs). As a result, the AGE profile was significantly enlarged to more than 12 structures, and comprehensive mechanistic insights were provided.

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The induction period (IP) of ethyl linoleate stressed at 60 °C was monitored via the formation of hydroperoxides. The addition of lycopene (1% w/w) increased the IP from 7.0 to 10.

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In the present study, the degradation of -glucosidic dihydrochalcone aspalathin as the major phenolic compound in rooibos () was investigated. Analyses by gas chromatography-mass spectrometry of aqueous aspalathin-lysine incubations after silylation showed the formation of dihydrocaffeic acid [3-(3,4-dihydroxyphenyl)-propionic acid] under oxidative conditions as a novel degradation product up to 10 mol %. High-performance liquid chromatography analyses revealed the concurrent formation of the dihydrocaffeic acid lysine amide at about 30-fold lower concentrations, which was unequivocally verified by synthesis of an authentic reference standard.

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2-Acetyl-1-pyrroline (2-AP) is a key odorant in many foods, such as aromatic rice and wheat bread, with a very low odor threshold of 0.05 μg/L in water. The small molecule with a popcornlike, roasty odor is generated biologically or by Strecker degradation within the Maillard-reaction cascades during thermal food processing with methylglyoxal and 1-pyrroline as the main direct precursors.

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Objective: In this study, we aim to describe the post-sepsis syndrome from the perspective of the sepsis survivors.

Design And Setting: The study is a prospective, observational online international survey.

Participants: Sepsis survivors enrolled via social media from 13 September 2014 to 13 September 2016.

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The present study aimed to investigate the influence of singlet oxygen and radical species on the isomerization of carotenoids. On the one hand, lycopene and β-carotene standards were incubated with 1,4-dimethylnaphthalene-1,4-endoperoxide that produced singlet oxygen in situ. (13Z)- and (15Z)-β-carotene were preferentially generated at low concentrations of singlet oxygen, while high concentrations resulted in formation of (9Z)-β-carotene.

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This study aimed to evaluate the influence of different light regimens during spinach cultivation on the isomeric composition of β-carotene. Irradiation with a halogen lamp, which has a wavelength spectrum close to that of daylight, was used to mimic field-grown conditions. The additional use of optical filters was established as a model system for greenhouse cultivation.

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The present study aimed to investigate if growth conditions have an impact on the isomeric composition of lycopene in tomatoes. First a model system for photoinduced isomerization was established. Tomato extracts were irradiated with a halogen lamp, whose wavelength spectrum is close to the spectrum of daylight and thus mimics field-grown cultivation.

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