Aim: The aim of this study is to investigate the polyphenol composition and distribution in the core, flesh, and peel of 20 apple varieties from China and its relation with browning characteristics of apple slices in the drying process. Methods: In this paper, the prominent phenolic compounds, which was determined by photo diode array-high-performance liquid chromatography (PDA-HPLC), and the chromatic value [coherent infrared energy (CIE) L*, a*, b*] were correlation analysised. Results: The results showed that apple core, flesh, and peel were characterized by phloridzin, chlorogenic acid, quercetin, and related derivatives respectively. The 20 apple varieties showed a significant difference (* P>0.05) in browning variation in the drying process. The browning at the initial stage was mainly L* declined, which was induced by polyphenols enzymatic oxidation. While the browning was characterized by b* and a* value increment at the end of the drying process, where the Maillard reaction was the dominant factor. Conclusions: The correlation distance between the main phenolic compounds in apple core, flesh, and peel with the average chromatic L*, a*, and b* values varied at different stages of the drying process.

Aim: The aim of this study is to comprehensively investigate the distribution of amine and phenol compounds in different flavors of Baijiu. Methods: ¹²C-/¹³C-dansyl chloride labeling was applied for untargeted and quantitative analyses of amine and phenol compounds in Baijiu. Results: A total of 267 amine/phenol compounds were detected, and 30 of them were confirmed by the standards. 4 of 30 confirmed compounds were newly identified in Baijiu, and 16 ones were related with flavor or biological activity. After statistical analysis, 34 amine/phenol compounds were defined as potential markers for indicating sauce flavor, strong flavor, and light flavor Baijiu. 30 compounds in Baijiu were quantified with high precision, high accuracy, and high sensitivity. Results of the untargeted and quantitative analyses indicated that the number and contents of amine and phenol compounds were generally richest in sauce flavor Baijiu, while lowest in light flavor Baijiu. Conclusions: The results obtained in the research are beneficial for comprehensively understanding the amine and phenol compounds in Baijiu and further provide the basis for the flavor blending of Baijiu.

Aim: This study aims to develop sensitive and reliable analytical technologies to enable the distinction between wild-caught and farmed fish through appropriate molecular markers to protect consumers from fraudulent fish labelling. Gilthead sea bream,Sparus aurata L. (S. aurata L.), is a very common fish used as foodstuff worldwide and globally produced in aquaculture in the Mediterranean basin. Wild-caught and farmed species are very different in feed and lifestyle and the quality and safety of these products strongly depend on fish growth, processing history, and storage conditions. Methods: Hydrophilic interaction liquid chromatography (HILIC) coupled with electrospray ionization (ESI) and Fourier-transform mass spectrometry (FTMS; HILIC-ESI-FTMS) was employed to discriminate the phospholipidome profiles of fillets extracts of wild-caught from farmed gilthead sea breams. Results: The untargeted approach led to the annotation of a total of 216 phospholipids (PLs), namely 65 phosphatidylethanolamines (PEs), 27 lyso-PEs (LPEs), 61 phosphatidylcholines (PCs), 34 lyso-PCs (LPCs), and 29 sphingomyelins (SMs). Untargeted lipidomics data were investigated by principal component analysis (PCA) and K-means clustering. Lyso-PLs (LPLs) of PEs and PCs including ether-linked side chains were found as discriminating markers between the two types of fish samples. The PLs that were most responsible for distinguishing between the lipid extracts of farmed and wild S. aurata fillets were successfully characterized by tandem mass spectrometry (MS/MS). The analysis revealed that wild fillet lipid extracts contained some PE exhibiting ether bonds (PE P-), viz. 16:0, 18:0, 18:1, and 18:2 and polyunsaturated fatty acyl chains (i.e., 22:6 and 22:5). In farmed species, the estimated abundance ratios of fatty acyl chains 20:4/18:2 and 22:6/20:5 were 0.9 and 0.05, respectively. However, in wild-caught fish, these ratios were found to be two-fold higher and four-fold higher, respectively. Conclusions: This work demonstrates that the combination of HILIC-ESI-FTMS and chemometrics can serve as a valuable tool for evaluating fish authenticity and assessing quality concerns by monitoring specific lipid ratios.