Search results for "aroma"
showing 10 items of 1006 documents
Evaluation of the aroma compounds of Sicilian Cactus pear (Opuntia Ficus-Indica) fermented juice
2011
Investigating the effect of meat products ingredients and reaction mechanisms for enchancing savory and toasted aromas in dry cured meat products
2023
En la carne cocinada, las notas olfativas cárnicas y tostadas son producidas mediante reacciones de degradación y transformación de aminoácidos que contienen átomos de azufre (Cys, Cis y Met), aminoácidos nitrogenados (Pro y Orn), así como de la vitamina tiamina. Sin embargo, en los productos curados madurados no se conocen los mecanismos de formación de los compuestos aromáticos que producen notas cárnicas y tostadas, así como su impacto en el aroma curado-madurado. Entre los productos cárnicos curados madurados que se elaboran en el área mediterránea se encuentran los sometidos a procesos de fermentación como los embutidos fermentados, y los curados-madurados como los lomos y jamones cura…
Desarrollo de embutidos con menores niveles de nitrificantes inoculados con levaduras seleccionadas para mantener las características sensoriales pro…
2020
Los agentes de curado (nitratos y nitritos) desempeñan funciones importantes en la elaboración de embutidos curado-madurados, entre las que se encuentra el desarrollo del aroma característico de estos productos. El uso exclusivo de nitrato, de nitrito o de una mezcla de los dos, puede tener diferente repercusión en el perfil aromático. Sin embargo, existe una tendencia a la reducción del uso de estos aditivos por su relación con la generación de N-nitrosaminas que ha hecho que en los últimos años exista una gran preocupación a nivel de los consumidores. Por ello, en la presente tesis doctoral se ha estudiado el efecto que produce la reducción de la cantidad añadida de nitrato o de la mezcla…
Asymmetric synthesis of functionalized tetrahydrofluorenones via an NHC-catalyzed homoenolate Michael addition
2018
The first example of an N-heterocyclic carbene-catalyzed asymmetric desymmetrization of enal-tethered cyclohexadienones via an intramolecular homoenolate Michael addition/esterification reaction is described. This new protocol offers a direct entry to various functionalized tetrahydrofluorenones with three contiguous stereocenters in high yields, good diastereoselectivities and excellent enantioselectivities.
Fluorescence enhancement of quinolines by protonation.
2020
A study of the fluorescence enhancement of isoquinoline, acridine (benzo[b]quinoline) and benzo[h]quinoline is reported with six organic acids of different pKa values. Protonation was found to be an effective tool in the fluorescence enhancement of quinolines. A significant increase in the fluorescence intensity is observed only when strong acids are used, resulting in an over 50-fold increase in fluorescence with trifluoroacetic or benzenesulfonic acid and isoquinoline in a 1.5 : 1 ratio. The benzenesulfonic acid was found to be the most effective in the protonation of the bases despite its higher pKa value compared to trifluoro- and trichloroacetic acid. The X-ray crystal structures of 14…
Nonlinear optical properties of diaromatic stilbene, butadiene and thiophene derivatives
2021
Series of highly polar stilbene (1a–e), diphenylbutadiene (2a–c) and phenylethenylthiophene (3a–c) derivatives were prepared via Horner–Wadsworth–Emmons method with a view to produce new and efficient materials for second harmonic generation (SHG) in the solid-state. The single-crystal X-ray structures of compounds 1–3 reveal extensive polymorphism and a peculiar photodimerization of the 2-chloro-3,4-dimethoxy-4′-nitrostilbene derivative 1a to afford two polymorphs of tetra-aryl cyclobutane 4. The stilbene congeners 2-chloro-3,4-dimethoxy-4′-nitrostilbene (1a·non-centro), 5-bromo-2-hydroxy-3-nitro-4′-nitrostilbene (1b) and 4-dimethylamino-4′-nitrostilbene (1e), as well as 4′-fluoro-4′′-nitr…
Towards low-energy-light-driven bistable photoswitches : ortho-fluoroaminoazobenzenes
2021
AbstractThermally stable photoswitches that are driven with low-energy light are rare, yet crucial for extending the applicability of photoresponsive molecules and materials towards, e.g., living systems. Combined ortho-fluorination and -amination couples high visible light absorptivity of o-aminoazobenzenes with the extraordinary bistability of o-fluoroazobenzenes. Herein, we report a library of easily accessible o-aminofluoroazobenzenes and establish structure–property relationships regarding spectral qualities, visible light isomerization efficiency and thermal stability of the cis-isomer with respect to the degree of o-substitution and choice of amino substituent. We rationalize the exp…
Design, Construction, and Characterization of a New Regioisomer and Diastereomer Material Based on the Spirooxindole Scaffold Incorporating a Sulphon…
2020
The 1,3-dipolar cycloaddition reaction is one of the most rapid, and efficient protocols to access, and construct highly divergent heterocycle chiral auxiliaries. Free catalyst synthesis of spirooxindole scaffold incorporating sulphone moiety via one pot&ndash
Mono-nitrotolueenien muuntuminen
2008
Synthesis of N‐Fused Indolines via Copper (II)‐Catalyzed Dearomatizing Cyclization of Indoles
2021
Advanced synthesis & catalysis 363(12), 3121-3126 (2021). doi:10.1002/adsc.202100290