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Ellagitannins are the main extractible phenolic compounds in oak wood; the monomers vescalagin and castalagin, lyxose/xylose-bearing monomers grandinin and roburin E, dimers roburins A and D and lyxose/xylose-bearing dimers roburins B and C are the principal ones. These compounds are responsible for the high durability of wood and may contribute to the organoleptic quality of wines and spirits (color, astringency, bitterness). Despite their importance, their presence and forms in distilled spirits are not well known. The aim of this work was therefore to develop and validate a method to identify and quantify oak wood ellagitannins in Cognac using high liquid chromatography-triple quadrupole (LC-QQQ) analysis. The method was validated using vescalagin as the standard and by studying sensitivity, linearity in working range, intraday repeatability, and intraday precision in order to quantify individual ellagitannins in this complex matrix.The microbial compositions, quality characteristics, and structural changes in fresh brown rice noodles (FBRN) during storage were investigated. Total plate count and mold and yeast counts increased while the pH decreased during storage. Metagenomic sequencing revealed that the microbial composition of FBRN changed throughout storage. A comprehensive investigation of the variation in lipid content demonstrated that hydrolytic rancidity was responsible for lipid deterioration. LF-NMR showed an increase in the proportion of bound water and a decrease in the proportion of free water in FBRN. Moreover, significant changes in edible qualities were observed. The cooking loss increased three-fold and noodles hardness reduced by approximately 23%. Further, the high initial aldehyde content of FBRN diminished almost completely, while that of alcohols and esters increased, leading to significant flavor deterioration. The correlation and factor analysis suggested that the TPC and MY counts could be used as key indicators of FBRN deterioration.Tea saponins from Camellia oleifera Abel. seed pomace are new sources of commercial saponins. This study established an eco-friendly and efficient extraction method for tea saponins from C. oleifera seed pomace. A ternary deep eutectic solvent (DES) composed of l-proline, glycerol and sucrose (4101 in molar ratio, abbreviated as PGS-5) achieved the highest extraction yield of tea saponins among all screened DESs. A maximum extraction yield of 23.22 ± 0.28% was obtained using PGS-5 under the optimized extraction time, DES concentration and liquid-solid ratio. Through ultraviolet, Fourier transform infrared spectroscopy and ultrahigh-performance liquid chromatography-Q Exactive HF mass spectroscopy, as well as analyses of antioxidant and antimicrobial activities, it was determined that extracted saponins did not altered during processing. Therefore, PGS-5 can serve as a solvent to obtain stable and beneficial tea saponins from C. oleifera seed pomace.A microfluidic device for simultaneous analysis of total flavonoids and total phenolic acids is presented for the first time. The process was based on the utilization of magnetic zinc-imidazole frameworks (ZIF-4), as a highly efficient media for on-line separation of phenolic acids and flavonoids, which were subsequently detected by a sensitive chemiluminescence (CL) method. XL092 datasheet Acrylate-based polymeric microchips containing a separation column (12.5 mm length, 3 mm width and 1 mm depth) were fabricated using a 3D-printer, and magnetic ZIF-4 was fixed into the column. The high porosity of the magnetic ZIF-4 made it a suitable adsorbent, guaranteeing an effective separation. The detection limits were in the range of 0.04-0.10 µg mL-1 with relative standard deviation values of (2.19-4.38%). The system was successfully applied for the analysis of flavonoids and phenolic acids in tea and honey samples. The recovery was from 95.4 to 104.1%, indicating a good accuracy of the developed method.Activity of odor compounds of soy sauces has not been fully determined so far. Herein, a new switchable GC/GC × GC-olfactometry-mass spectrometry system for simultaneous GC × GC-MS analysis and sniffing of each odor-active substance through a single injection was used for the aroma extract dilution analysis of five regular high-salt liquid-state soy sauces (HLS). Methional, maltol, guaiacol, 4-ethylguaiacol, 2-acetylpyrrole, 2-acetylfuran, 2-phenylethanol, and 4-hydroxy-2,5-dimethyl-3(2H)-furanone showed high flavor dilution (FD) factors. The FD factors of all odor-active compounds in different odor attributes were summed up (score) to evaluate the odor characteristics of the samples. Cooked potato-like odor was the most important characteristic. The difference in the odor characteristics were mainly reflected in the balance of caramel-like/sweet, roasted/roasted nut-like, spicy/burnt, and unpleasant odor intensity; the fruity odor intensity was the weakest. This study will provide a better understanding of the odor characteristics and key odor-active compounds in Chinese regular commercial HLS.Glucose oxidase (Gox) is a biocatalyst that is widely applied in the food industry, as well as other biotechnological industries. However, the industrial application of Gox is hampered by its low thermostability and activity. Here, we aimed to improve the thermostability of GoxM4 from Aspergillus niger without reducing its activity due to the activity-stability trade-off. A simple and effective approach combining enzyme activity and structure stability was adopted to evaluate the thermostability of GoxM4 and its mutants. After four rounds of computer-aided rational design, the best mutant, GoxM8, was obtained. The melting temperature (Tm) of GoxM8 was increased by 9 °C compared with GoxM4. The catalytic efficiency of GoxM8 was similar to GoxM4, suggesting that the enzyme activity-stability trade-off was counteracted. To explore its mechanism, we performed molecular dynamics simulations of GoxM4 and its mutants. Our findings provided a typical example for researching the enzyme activity-stability trade-off.Compared with absorbance, scattering-based dynamic light scattering (DLS) signal has higher sensitivity because its light-scattering intensity is very sensitive to changes in size, thereby enhancing the sensitivity. Herein, we first developed a DLS-enhanced direct competitive enzyme-linked immunosorbent assay (DLS-dcELISA) for ultrasensitive detection of aflatoxin B1 (AFB1) in corn. By using hydroxyl radical-induced gold nanoparticle (AuNP) aggregation to amplify AuNP scattering signals, the developed DLS-dcELISA exhibited ultrahigh sensitivity for AFB1. The detection limit was 0.12 pg mL-1, which was 153- and 385-fold lower than those obtained using plasmonic and colorimetric dcELISA. In addition, the DLS-dcELISA exhibited excellent selectivity, high accuracy, and strong practicality. Overall, this work presented a simple and universal strategy for improving the sensitivity of traditional ELISA platform only by using the sensitive DLS signals. This technique can replace absorbance-based plasmonic or colored signals as immunoassay signal output for enhanced competitive detection of mycotoxins.