The kinetics of browning and the correlation between browning products (BPs) and pyrazine compounds were investigated by heating equimolar l-ascorbic acid (ASA)/acidic amino acids under weak alkaline conditions at 120-150°C for 10-120min. The formations of BPs and pyrazine compounds from the reaction were monitored by UV-vis and SPME-GC-FID, respectively. The formation of BPs in both ASA/l-glutamic acid and ASA/l-aspartic acid model reaction systems followed zero order reaction kinetics with activation energies (E) of 90.13 and 93.38kJ/mol, respectively. ASA/l-aspartic acid browned at a slightly higher rate than ASA/l-glutamic acid. The total concentration of pyrazine compounds was highly and positively correlated with that of BPs. Based on the observed kinetic data, the formation mechanisms of BPs and pyrazine compounds were proposed.
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http://dx.doi.org/10.1016/j.foodchem.2016.10.119 | DOI Listing |
Food Chem X
January 2025
School of Liquor and Food Engineering, Guizhou University, Guiyang 550025, China.
Douchiba (DCB) is a nutritious food rich in various functional components such as Tetramethylpyrazine (TTMP), and the strain fermentation is crucial for enhancing its quality. This work utilized S2-2 and S6-J1 with high TTMP production for fermentation of soybeans to optimize the pre-fermentation process and to evaluate the flavor quality of mature DCB. The concentration of TTMP in DCB fermented by mixed microbial (MG) was 2.
View Article and Find Full Text PDFFood Chem
December 2024
School of Light Industry Science and Engineering, School of Food Science and Health, Beijing Technology and Business University (BTBU), Beijing 100048, China.. Electronic address:
To understand flavor formation mechanisms in complex meat-like Maillard systems, effect of lysine on cysteine-xylose reaction to form flavors was studied. GC-MS and GC-O analyses found lysine of 1 times cysteine concentration led to the greatest amount of sulfur-containing meaty compounds while more additional lysine caused more pyrazine compounds. LC-MS analysis showed lysine competed with cysteine to form the early-stage intermediate of Lys-Amadori compounds and accelerated conversion of 2-threityl-thiazolidine-4-carboxylic acids to Cys-Amadori compounds from the cysteine-xylose reaction.
View Article and Find Full Text PDFEur J Med Chem
December 2024
Department of Medicinal Chemistry, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran. Electronic address:
Over the past two decades, small molecules bearing [5,6]-bicyclic nitrogen-containing cores have emerged as one of the most extensively studied structures for the development of selective c-MET kinase inhibitors. Structure-activity relationship (SAR) studies have demonstrated that modifying these cores can significantly impact the biological properties of c-MET inhibitors, including safety/toxicity, potency, and metabolic stability. For example, although c-MET kinase inhibitors containing the [1,2,4]triazolo[4,3-b][1,2,4]triazine scaffold (core P) exhibit high inhibitory potency, they often face challenges due to metabolic stability defects.
View Article and Find Full Text PDFFront Immunol
December 2024
Molecular Thyroid Research Laboratory, Department of Medicine I, Johannes Gutenberg-University (JGU) Medical Center, Mainz, Germany.
Background: The insulin-like growth factor 1 receptor (IGF-1R) and the thyrotropin receptor (TSH-R) are expressed on orbital cells and thyrocytes. These receptors are targeted in autoimmune-induced thyroid eye disease (TED). Effective therapeutic treatment of TED inhibits activation of the IGF-1R/TSH-R complex.
View Article and Find Full Text PDFBioresour Technol
December 2024
Institute of Clean Coal Technology, East China University of Science and Technology, Shanghai 200237, P.R. China.
Hydrothermal pretreatment (HTP) is used to increase the biochemical methane potential (BMP) of food waste (FW). The formation of melanoidins will seriously affect the microbial activity and methane production during anaerobic digestion (AD). Based on spectroscopic methods, similarities and heterogeneity of melanoidins from different sources were investigated, and the wide peak band (260-350 nm) in the ultraviolet region and the differences of amide groups of fructose-amino acid system, fructose-casein system and FW system were revealed.
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