To analyze the characteristics of sugar and acid components in fruits of different Syzygium samarangense germplasms resources, screen key indicators suitable for evaluating the sugar and acid quality of Syzygium samarangense.

The sugar and acid components of 18 Syzygium samarangense germplasms were determined by high performance liquid chromatography, and principal component analysis and cluster analysis were used to analyze the characteristics of sugar and acid components.

The total sugar content of Syzygium samarangense fruits ranged from 35.12 to 114.29 mg/g, with an average of 59.66 mg/g and a coefficient of variation of 38.88%. The germplasms ‘Zihong’ and ‘Daye’ exhibited the highest total sugar contents, whereas ‘Malaysia Green’ had the lowest. Fructose and glucose were the main sugar components, accounting for 51.78% and 46.00% of the total sugar respectively. Total acid content ranged from 0.403 to 3.654 mg/g, with an average of 1.396 mg/g and a coefficient of variation of 57.64%. The germplasm ‘Heitang Barbie’ had the highest total acid content. Citric acid and malic acid were the major organic acids, together constituting 90.26% of the total acid content. Correlation analysis revealed that total sugar was highly positively correlated with fructose and glucose (r=0.9963 and 0.9961, P<0.01), whereas the sweetness-acid ratio showed highly significant negative correlations with citric acid and total acid(r=–0.6222 and –0.6998, P<0.01). Principal component analysis selected total sugar, total acid and sweetness-acid ratio as the core evaluation indices for sugar-acid quality.

The sugar and acid components of Syzygium samarangense exhibit significant differences. Fructose and glucose are the main sweet substances in the fruit, while citric acid and malic acid are the main acidic substances. Total sugar, total acid and the sweetness-acid ratio can be used as core indicators for evaluating the sugar-acid quality of Syzygium samarangense.

To investigate the effects regularity of ultraviolet aging duration on the migration behavior of lead (Pb), acrylamide (AM) and 1,2-benzisothiazolin-3-one (BIT) in polylactic acid (PLA)/plant fiber composite food contact material, and reveal their microstructural evolution mechanism.

Ultraviolet accelerated aging tests were conducted to simulate natural aging. The changes in chemical structure were analyzed by Fourier transform infrared spectroscopy (FTIR), and the surface morphology of the material was observed by scanning electron microscopy (SEM). Migration levels of Pb, AM, and BIT into 4% acetic acid and olive oil food simulants were quantitatively determined at different migration time points (2 h to 48 h) by inductively coupled plasma mass spectrometry (ICP-MS) and high performance liquid chromatography (HPLC), respectively.

Long term ultraviolet aging promoted the migration of harmful substances. For the 45 d aging group, the 48 h migration amounts of Pb, AM and BIT increased to 15.10, 132.15 and 21.80 mg/kg, with increases of 46.7% (Pb), 56.1% (AM) and 47.3% (BIT) compared with the 0 d group. SEM observations showed that microcracks and pores formed on the material surface. FTIR analysis indicated photoxidative chain scission occurred in the PLA molecular chains, with the enhancement of carbonyl and hydroxyl peaks. Over 60% of the total 48 h migration for each substance occurred within the first 24 h.

It is recommended to add ultraviolet absorbers or coatings to improve the aging resistance of the material. For materials without anti-ultraviolet measures, based on the migration data of the aging experiment, the shelf life of the material is recommended to not exceed 240 d.

To detect the residues of 6 kinds of heavy metals in Polygonatum cyrtonema from different producing areas and conduct health risk assessment.

Inductively coupled plasma mass spectrometry was used to determine the heavy metal residues in Polygonatum cyrtonema from different producing areas. The estimated daily intake (EDI), target hazard quotient (THQ) and lifetime cancer risk (LCR) were applied to evaluate the health risks of Polygonatum cyrtonema from different producing areas.

Compared with the heavy metal limit standards of the Chinese pharmacopoeia and other countries, the levels of As and Cu in Polygonatum cyrtonema from different producing areas did not exceed the standards. Among them, the Cd content in Polygonatum cyrtonema from 4 producing areas (Shang Shuli, Rongcheng, Jingde, Xihua) exceeded the International Organization for Standardization (ISO) standard, and the Pb content in Polygonatum cyrtonema from 4 producing areas (Shang Shuli, Rongcheng_, Xihua, Shien) exceeded the standard specified in the Chinese pharmacopoeia. However, when compared with standards of other countries, the Cd content in Polygonatum cyrtonema from 10 producing areas exceeded the standards to varying degrees, and the Pb content exceeded the standards of 4 countries. In comparison with the chromium (Cr) standards of Canada and the United States, the Cr content in Polygonatum cyrtonema from all 15 producing areas exceeded the limits. For the EDI, except for the Cd in Polygonatum cyrtonemafrom Shang Shuli, Rongcheng and Xihua (with values of 0.001301, 0.001190 and 0.002751 respectively, which exceeded the provisional tolerable daily intake (PTDI) limit of 0.00083, the heavy metal content in other Polygonatum cyrtonema samples did not exceed the PTDI limits. The target hazard quotient (THQ) analysis showed that, except for Hg in Polygonatum cyrtonema from Shang Shuli (with a value of 1.172466, indicating a non-carcinogenic risk), the risk levels of other single heavy metal elements in all sample sites were less than 1. Regarding the total non-carcinogenic risk, the values in Shang Shuli and Xihua reached 1.240582 and 1.476055 respectively, suggesting that the intake of Polygonatum cyrtonema from these two areas may pose non-carcinogenic risks due to heavy metals, while no such risks existed in other sample sites. For carcinogenic risks, unacceptable carcinogenic risks were found in a large number of sample sites.

The assessment results of EDI and non-carcinogenic risk index of heavy metals show that the health risks of heavy metals in Polygonatum cyrtonema to humans are relatively low. However, in the carcinogenic risk assessment, unacceptable carcinogenic risks are found in many producing areas. Therefore, it is necessary to attach importance to the heavy metal pollution of Polygonatum cyrtonema, strengthen the detection of heavy metals, so as to ensure the safety of traditional Chinese medicine and protect human life and health.

To explore the sensory drivers influencing consumer preferences for three-stage infant formula.

Gas chromatography-ion mobility spectrometry (GC-IMS), quantitative descriptive analysis(QDA) and consumer tests were employed to conduct an analysis of the aroma compounds, sensory characteristics and consumer preferences of infant formulas, respectively. Subsequently, the obtained results were correlated to establish a correlation network.

A total of 62 aroma substances were detected by GC-IMS, and notable differences existed in the aroma composition characteristics of infant formula with varying storage durations. The results of the consumer test showed that the consumer preference decreased significantly with the increase of storage time. And the results of sensory evaluation indicated that T-sweet, milky, creamy and eggy were the main characteristic attributes of the 3-stage infant formula. Conversely, fishy and oxidization odors were identified as the primary off-flavors. Moreover, the scores of these two off-flavors increased notably as the storage extended, whereas the scores of the other characteristic aromas decreased marginally. The findings of the correlation analysis demonstrated that milky, creamy and T-sweet were the primary sensory drivers affecting consumer preferences. Meanwhile, aldehydes, namely 1-hexanal (A7), 2-hexenal (A8), (Z)-4-heptenal (A11) and butanal (A23); ketones, specifically 2,3-butanedione (B2), acetoin (B6) and 3-octanone (B9); alcohol compounds 1-pentanol (C3), 1-pentanol(C4); and olefin compounds α-phellandrene (G5), p-cymene (G9) could serve as sensory-markers leading to alterations in the sensory profiles of infant formula.

Sensory attributes represent the most direct and intuitive way through which consumers perceive a product, and they directly influence consumers’ preferences for the product. Regarding infant formula, consumers exhibit a greater interest in the typical flavor of the product than in the off-flavor. Therefore, GC-IMS can be employed for the rapid detection of sensory-markers. These compounds can be utilized to analyze the sensory characteristics of products and, consequently, forecast consumer preferences. This study will provide a data base for the quality control of infant formula and the maintenance of consumer preference, and provide a stable and rapid testing and analyzing process for aroma compounds to related enterprises.

To investigate the migration characteristics and compliance risks of 19 kinds of organophosphorus esters (OPEs) in milk powder packaging materials, and conduct targeted food safety risk assessment.

This study selected 12 typical milk powder packaging materials [including canned, bagged, and production-use polyethylene (PE) bags], determined the migration amounts of 19 kinds of target OPEs by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and conducted a targeted risk assessment by integrating hazard analysis and exposure levels.

OPEs were detected in 7 out of 12 materials, with 3 kinds of target compounds identified, namely tri-n-butyl phosphate (TnBP), triphenyl phosphate (TPhP), and tris(2,4-di-tert-butylphenyl) phosphate (AO168O). Among them, AO168O had the highest detection rate (41.67%) with a maximum migration amount of 0.02970 mg/kg. Compliance evaluation showed that TnBP met the limit requirements of GB 9685—2016 National food safety standard-Uses of additives in food contact materials and articles, while there were no explicit relevant regulations that clearly authorize the use of TPhP and AO168O. Risk assessment indicated that the exposure risk quotients of OPEs ranged from 0.088% to 1.650% for the general population and from 0.789% to 14.850% for infants and young children, with the overall risk being at an acceptable level.

This study clarifies the migration status and risk levels of OPEs in milk powder packaging materials, providing data reference for milk powder production and packaging enterprises to establish a full-chain OPEs risk investigation and traceability mechanism and focus on controlling the migration risk of AO168O.

To understand the situation of pesticide residues in fruits in circulation in Nanchang City in 2024, and quickly screen for multiple pesticide residues in fruits by orbitrap high-resolution mass spectrometry(Orbitrap HRMS).

The fruit samples were purified by QuEChERS method, combined with Orbitrap HRMS, more than 1200 kinds of pesticides and their metabolites were rapidly screened for 721 batches of 15 kinds of fruits collected. According to GB 2763—2021 National food safety standard-Maximum residue limits for pesticides in food, the test results were evaluated, and exceeding the maximum residue limit was considered unqualified.

The results of qualitative and semi-quantitative screening based on the database established through the testing and analysis of matrix-spiked samples showed that the pesticide residues in fruits were generally under safe control. The overall pass rate of pesticide residues in the samples was 92.8%. A few batches of samples had pesticide residues that were unqualified (unqualified rate 7.2%), with detections of prohibited and restricted pesticides in an even smaller number of batches (detection rate 2.9%).

Based on the screening results of HRMS, the qualified rate of pesticide residues in circulating fruits in Nanchang City in 2024 is 92.8%, and the overall risk is controllable. There are a small number of samples that are unqualified and banned pesticides detected, and continuous supervision is needed.

To study the variation pattern of biogenic amines during vinegar fermentation, and explore the influence of production conditions on the accumulation of biogenic amines.

The content of biogenic amines at different fermentation stages was analyzed using high performance liquid chromatography(HPLC). At the same time, the effects of the ratio of material to liquid (1:1.1, 1:1.2, 1:1.3, g:mL), the addition amount of acetic acid bacteria (1.0%, 1.5%, 2.0%) and Aspergillus niger (0.5%, 1.0%, 1.5%) on biogenic amines during vinegar fermentation were investigated.

The biogenic amine content in vinegar increased first and then decreased with the fermentation time. When the ratio of material to liquid was 1:1.2 (g:mL), the biogenic amine content of vinegar after fermentation was the highest, which was 190.49 mg/kg. When the addition of acetic acid bacteria was 2.0%, the biogenic amine content of vinegar after fermentation was the highest, which was 220.12 mg/kg. When the addition of Aspergillus niger was 1.5%, the biogenic amine content of vinegar after fermentation was the highest, which was 228.29 mg/kg.

As a harmful substance in vinegar fermentation, excessive content of biogenic amines will have a certain impact on human health. By changing the ratio of material to liquid, the addition amount of acetic acid bacteria and Aspergillus niger, the formation of biogenic amines in vinegar fermentation can be affected, thus effectively improving the safety of vinegar.

To establish a method for the simultaneous determination of prometryn and fenpropathrin residue in Apostichopus japonicus by solid-phase extraction-gas chromatography-mass spectrometry (SPE-GC/MS).

The samples were extracted with acetonitrile. The extracts were purified using a Cleanert Florisil solid-phase extraction column and then reconstituted in n-hexane. Matrix-matched standard solutions were prepared, and detection was performed in selected ion monitoring mode. The effects of different extraction solvents, solvent volumes, solid-phase extraction columns and elution ratios on extraction efficiency were compared.

At spiked levels of 5–20 μg/kg, the recoveries of prometryn ranged from 86.3% to 106.0%, with relative standard deviations of 5.4%–11.6%, and the limit of quantitation was 5 μg/kg. For fenpropathrin at spiked levels of 7–20 μg/kg, the recoveries ranged from 95.9%–113.6%, with relative standard deviations of 4.1%–10.8%, and the limit of quantitation was 7 μg/kg.

This method is simple, efficient and accurate, making it suitable for both qualitative and quantitative determination of prometryn and fenpropathrin residues in Apostichopus japonicus.

To establish an untargeted screening method for rapidly identifying pesticide residues and their metabolites in Triticum aestivum L. by ultra performance liquid chromatography coupled to quadrupole-orbitrap high-resolution mass spectrometry (UPLC-Q-Orbitrap HRMS) combined with a molecular networking strategy.

Fortified Triticum aestivum L. samples were analyzed using UPLC-Q-Orbitrap HRMS to acquire high-resolution mass spectrometry data. The raw data were converted by MSConvert, imported into MZmine software for preprocessing, and then uploaded to the global natural products social molecular networking (GNPS) platform for constructing a visual molecular network. The effects of the MS2 spectral denoising threshold and GNPS network construction parameters (minimum matched fragment ions, minimum matched spectra for library search) on seed node identification efficiency were systematically investigated. Target compounds were identified by integrating accurate mass, retention time and characteristic fragment ion cleavage patterns.

Optimal network annotation rate (58.9%) and seed node recognition rate (94.9%) were achieved when the MS2 denoising parameter was set to 1.0E3, and both the minimum matched fragment ions and library search minimum matches in GNPS were set to 2. Under the optimized conditions, structurally similar pesticides were successfully clustered and identified through molecular networking, along with the metabolites of oxamyl, pirimicarb, prochloraz, phosmet and malathion, with their major fragmentation pathways elucidated.

A UPLC-Q-Orbitrap HRMS-molecular networking non-targeted screening strategy is developed, enabling rapid and efficient identification of structurally similar pesticide residues and metabolites in Triticum aestivum L.. This approach provides a reliable analytical framework and technical methodology for screening non-targeted pesticide residues and metabolites in complex matrices.

To establish a method for determining caffeine content in tea by ultra performance liquid chromatography-triple quadrupole mass spectrometry.

The samples were separated on a BEH C₁₈ column(2.1 mm×50 mm, 1.7 μm) via isocratic elution with a mobile phase consisting of 0.1% formic acid in water and acetonitrile (80:20, V:V). The flow rate was set at 0.3 mL/min, with an injection volume of 5 μL and a column temperature maintained at 25 ℃. Quantification was performed using the external standard method. Mass spectrometric analysis was conducted in the positive mode with the quantitative ion pair being m/z 195.0/137.9, and the qualitative ion pairs being m/z 195.0/109.9 and m/z 195.0/82.9. The capillary voltage was set at 1.00 kV, the cone voltage was set at 50 V, the desolvation gas (N₂) temperature was set at 500 ℃, the desolvation gas (N₂) flow rate was set at 1000 L/Hr, the cone gas flow rate at was set 50 L/hr, and the collision gas was high-purity argon.

The results demonstrated a limit of detection was 0.25 ng/mL for caffeine. The method exhibited excellent linearity with in the mass concentration range of 1–2000 ng/mL, with a correlation coefficient (r) of 0.9994. The spike average recovery rates ranged from 101.6% to 106.6%, with relative standard deviation (RSD) between 1.47% and 3.12%(n=3). The precision, repeatability and stability results were all satisfactory.

This method is rapid, sensitive, offers high resolution and is well-suited for the quantitative analysis of caffeine in tea.