Search results for "PROTON-TRANSFER"
showing 4 items of 4 documents
The Dynamics of Aroma Release during the Consumption of Candies with Different Structures
2014
This chapter aims at investigating the role of candy texture on the dynamics of aroma release using dynamic instrumental and sensory methods. The highest in vivo release, monitored using proton transfer reaction mass spectrometry (PTR-MS), was obtained for the 2% gelatin sample for all aroma compounds. The temporal dominance of sensations (TDS) method highlighted that the dominant sensation for the liquid product was the “strawberry” note. For other products, the temporal characteristics of perceptions were more complex. Data highlighted that aroma release resulted from interaction between product properties and oral behavior. Some relations with the dynamics of perception have been establi…
Role of aroma–matrix interactions on perception of structured emulsions
2011
The impact of the composition of spreads on in vivo aroma release and aroma perception was investigated using online proton transfer reaction mass spectrometry (PTR-MS) and sensory methodologies. Consumption of model products spread on bread induced a significant increase in aroma release and better discrimination in aroma perception, compared to when the product was tasted pure from a spoon. Dynamic release of a series of 10 aroma compounds was slower with the increase in solid fat content, and the quantity decreased when proteins were added. Sensory ranking of model products mostly confirmed the release results.
The primary structural photoresponse of phytochrome proteins captured by a femtosecond X-ray laser
2019
Phytochrome proteins control the growth, reproduction, and photosynthesis of plants, fungi, and bacteria. Light is detected by a bilin cofactor, but it remains elusive how this leads to activation of the protein through structural changes. We present serial femtosecond X-ray crystallographic data of the chromophore-binding domains of a bacterial phytochrome at delay times of 1 ps and 10 ps after photoexcitation. The data reveal a twist of the D-ring, which leads to partial detachment of the chromophore from the protein. Unexpectedly, the conserved so-called pyrrole water is photodissociated from the chromophore, concomitant with movement of the A-ring and a key signaling aspartate. The chan…
The dynamics of aroma release during consumption of candies of different structures, and relationship with temporal perception
2011
; We investigated the role of both candy texture and eating technique (melting or chewing) on the dynamics of aroma release. One novelty of this type of analysis was the simultaneous application of instrumental and sensory analysis. Four candy textures were established based on their storage modulus at 1 Hz by varying the gelatine content between 0 and 15% w/w. The in vivo release of three aroma compounds was monitored using Proton Transfer Reaction Mass Spectrometry and with a trained panel of testers. The gelatine content had no significant effect on the headspace/product partition and diffusion properties of the aroma compounds. The highest in vivo release for all aroma compounds was ob…