Molecular Basis for the Simultaneous Enhancement of the Aroma-Generating Capacity and Bioactivity of Maillard Reaction Precursors through Mechanochemistry

Ball milling at ambient temperatures can accelerate the formation and accumulation of early-stage Maillard reaction intermediates considered important precursors of aromas and antioxidants. In this study, using chemical and biological assays, we explored the potential of sequential milling and heating to enhance the antioxidant and aroma-generating capacity of Maillard model systems. Milling (30 Hz/30 min) followed by dry heating (90 °C/30 min) of glycine or lysine with glucose significantly increased not only the intensity of their aroma-active compounds as analyzed by headspace-gas chromatography/mass spectrometry (HS-GC/MS) but also their free radical scavenging capacity as assessed by 2,2'-azino-bis-(3-ethylbenzothiazoneline-6-sulfonic acid) (ABTS) and oxygen radical absorbance capacity (ORAC) assays. This was attributed to the increased formation of redox-active endiol moieties and precursors of N,N-dialkyl-pyrazinium radical cation in the lysine system assessed by electrospray ionization-quadrupole time-of-flight/tandem mass spectrometry (ESI-QqTOF/MS/MS) analysis. The test samples also inhibited NO generation and cellular oxidative stress in RAW 264.7 murine macrophage cells, indicating size reduction induced by milling promoted paracellular absorption.

Study of the molecular-structural composition of alcoholic extracts of radio-induced potato tubers by mass spectrometry and EPR

This article presents data on electron paramagnetic resonance (EPR) and mass spectrometric analysis of potato tubers, irradiated with gamma rays, in order to examine and identify changes in the molecular composition of organic matter following radiation exposure. The products of the Maillard reaction were compared with the products of intramolecular radiolysis of organic constituents of potatoes. The presence of free radicals was verified using EPR. DDPM (2,3-dihydro-3,5-dihydroxy-6-methyl-4 (H) -pyran-4-one) was among the radiolysis products detected via mass spectrometry, which points to the intramolecular dehydration of potato carbohydrates. EPR signals indicate single-electron transitions of the semidione radical anionic molecular compounds. It has been shown that irradiation with gamma rays significantly destroys the carbohydrate, lipid, keto-carotene and amino acid molecules of potatoes.

Effect of unsaturated fatty acids on glycation product formation pathways (Ⅰ) the role of oleic acid

Research on advanced glycation end-products (AGEs) and their formation pathways in food processing has gradually increased because AGEs are associated with human health, especially with involvement of lipids. In this study, radicals and glycation products were detected via electron spin resonance (ESR) and ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) respectively. The correlation of important intermediates was used to explain the effect of oleic acid (OA) on the glycation products and pathways. The results indicated OA participation decreased the content of stable radicals and glycosyl compounds in Maillard Reaction (MR). The oxidation of OA produced active radicals, and electron transfer caused lysine to transform radical form. These radicals participated in the formation of fructosyllysine (FL) with glucose (Glc) via the MR. The participation of OA is acted as inhibiting the way of Glc autoxidation and promoting the glycation pathway from FL to 3-deoxyglucosone (3-DG) to fluorescent-AGEs. Orthogonal projection to latent structures discriminant analysis results indicated that 3-DG, D-glucosone and methylglyoxal are key products in discriminating the glycation reaction.