To establish a sensory evaluation system suitable for commercially available steamed red bean buns and explore the correlation between sensory indicators and instrumental analysis parameters.

Sensory evaluation indicators were screened and their weights were determined based on the fuzzy binary contrast decision method, and an evaluation system was constructed in combination with expert consultation. The 12 kinds of commercially available steamed red bean bun samples were selected for sensory evaluation and instrumental analysis(texture, color difference, electronic nose, electronic tongue). Correlation analysis was used to clarify the relationship between sensory indicators and analysis parameters.

A sensory evaluation system comprising 8 indicators for steamed red bean buns was established, in which taste had the highest weight (0.20). Among the 12 kinds of commercial samples, sample 8 received the highest comprehensive sensory score. Texture analysis indicated that samples with lower hardness and chewiness generally achieved higher sensory scores. Colorimetric analysis showed that the L^* of all 12 kinds of samples exceeded 80. Correlation analysis revealed that the sensory score for crust color was highly significantly positively correlated with instrumental whiteness (P<0.001), chewiness was highly significantly positively correlated with hardness (P<0.001), aroma was highly significantly negatively correlated with the response values of electronic nose sensors W1W, W1S and W5S (P<0.001), and taste was significantly positively correlated with the reference signal value cycles per second (CPS) from the electronic tongue (P<0.05).

This study establishes a sensory evaluation system for commercially available steamed red bean buns and preliminarily validates the correlation between sensory indicators and analysis parameters, which can serve as a methodological reference for product quality evaluation and process optimization. Given that this study is based on a cross-sectional comparison of 12 kinds of commercial samples, further validation of the system’s applicability will benefit from expanded sample ranges and the inclusion of consumer preference comparisons.

To establish a method for the rapid detection of azithromycin residues in animal-derived foods by colloidal gold immunochromatographic assay (GICA).

By optimizing the pretreatment and the conditions of the test strip chromatography, the GICA was applied to the rapid detection of azithromycin in chicken, fish, pork, beef, lamb and the respective products. The limit of detection, sensitivity, false positive rate, false negative rate and cross reaction of the method were evaluated, and the accuracy was confirmed by liquid chromatography-tandem mass spectrometry(LC-MS/MS).

In this study of the rapid detection method, the limit of detection of azithromycin in animal-derived foods was 0.5 μg/kg, with the sensitivity 100%, false positive rate less than or equal to 2%, false negative rate 0%. There was no cross-reaction with gamithromycin, tulathromycin, tylvalosin, kitasamycin, erythromycin, spiramycin and tilmicosin. The coincidence rate between the test results and LC-MS/MS of actual samples was 100%.

The method is accurate, convenient, rapid and cheap, which is suitable for the high-throughput on-site rapid detection of azithromycin residues in animal-derived foods.

To optimize the preparation process of Hanzhong tea Mianpi and conduct quality evaluation.

Based on single-factor experiments, an L₁₆(4⁵) orthogonal array design was adopted, with sensory evaluation (including taste, appearance, odor, flavor and texture) as the scoring index. The effects of tea powder, zinc gluconate, sodium copper chlorophyll addition amount and pH of mixed slurry on the brightness and color variation of tea Mianpi were investigated using chromatic aberration measurement. Meanwhile, 5 texture parameters—hardness, cohesiveness, springiness, gumminess and chewiness—were determined by a texture analyzer. Using the SPSS PRO online data analysis platform, statistical analysis and multiple comparisons were performed on the comprehensively evaluated data from the orthogonal test to determine the optimal processing combination.

Orthogonal experiments determined the order of importance of factors affecting tea Mianpi quality as follows: green tea powder content>pH>zinc gluconate content>sodium copper chlorophyllin content. Based on a comprehensive analysis of sensory evaluation, chromatic aberration and texture, the optimal production process was 4.0% green tea powder,0.015% sodium copper chlorophyllin, 0.018% zinc gluconate, and a mixed slurry pH of 6.4.

Tea Mianpi produced using this optimized process feature a vibrant green color, a smooth and glossy surface, and a texture that is neither too soft nor too hard, offering a pleasant chewiness and elasticity. They boast a rich, refreshing aroma, providing a valuable reference for the development and utilization of Hanzhong tea Mianpi.

To establish a method for the rapid detection of key flavor substances in Baijiu base wine by mid-infrared spectroscopy.

Based on the linear relationship between the vibrational absorption intensity of mid-infrared spectroscopy and the content of functional groups in organic molecules, partial least squares regression was used to build quantitative models between mid-infrared spectroscopy of base wine and the concentrations of main flavor substances. Standard normal variate transformation and mean centering were applied for spectral preprocessing, and the RReliefF algorithm was employed to select the optimal wavenumber ranges and the number of principal components.

The optimized models exhibited stable and accurate performance. The coefficients of determination (R²) for ethyl acetate, ethyl lactate, ethyl hexanoate, methanol, n-butanol and acetic acid reached 0.998, 0.978, 0.996, 0.927, 0.904 and 0.771, respectively. In blind sample tests, most relative errors were controlled within 5%, and the average relative error of each index was below 4%.

There is a strong correlation between mid-infrared spectra and the content of flavor compounds in base wine. This method provides a reliable technical tool for the rapid detection of Chinese liquor base wine.

To investigate the effects of different structural parameters of C-flute corrugated paperboard on the cushioning performance of canned yellow peach.

According to the dimensions of metal cans containing yellow peach, a cushioning structure was constructed using C-flute corrugated paperboard. Drop tests were conducted to evaluate the cushioning performance under corner, edge and face drop conditions. The effects of buckle width, cushioning thickness and cushioning height on cushioning performance were analyzed by establishing acceleration variation curves. A ranking and scoring method were employed to optimize the structural parameters comprehensively, using paperboard consumption and cushioning performance as evaluation indices.

The optimal parameter combination was the buckle width of 20 mm, the cushioning thickness of 14 mm and the cushioning height of 20 mm. Under this condition, both good cushioning performance and reasonable material consumption were taken into account, and the cushioning effect was the best. When the cushioning thickness exceeded 14 mm, the performance improvement slowed down, and the acceleration rebounded obviously when the cushioning height exceeds 20 mm.

Among the 3 structural parameters, the buckle width and cushioning thickness have a significant effect on the cushioning performance, and the cushioning height has a relatively small effect. The acceleration value is larger in the corner and surface drop, and the protection of the corner and surface direction should be strengthened in the design. The optimized cushioning structure can not only give full play to the cushioning protection performance of C-flute corrugated paperboard, realize packaging reduction and integrity, but also take into account the requirements of economy and environmental protection.

To establish an analytical method for the simultaneous determination of forchlorfenuron and its metabolites, including 2-hydroxy-forchlorfenuron, 3-hydroxy-forchlorfenuron and 4-hydroxy-forchlorfenuron, in Actinidia chinensis Planch by QuEChERS-high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS).

The chromatographic-mass spectrometric conditions, including mobile phase, cone voltage and collision energy, as well as sample pretreatment procedures were optimized. Acetonitrile was used as the extraction solvent, followed by dehydration and salting-out with 5 g anhydrous magnesium sulfate and 1 g sodium chloride, and purification with a QuEChERS solid-phase extraction cartridge. The target analytes were simultaneously determined by HPLC-MS/MS and quantified using the matrix-matched external standard method.

Forchlorfenuron and the 3 kinds of metabolites showed good linearity in the range of 0–1.000 mg/L, with correlation coefficients (r) not lower than 0.995. The limits of detection and limits of quantitation were 0.0005 mg/kg and 0.002 mg/kg, respectively, indicating higher sensitivity than comparable methods. The average spiked recoveries ranged from 82.1% to 112.0%, with relative standard deviations of 0.4%–6.4%, demonstrating good accuracy and precision. The established method was applied to actual Actinidia chinensis Planch samples treated with forchlorfenuron. In Actinidia chinensis Planch samples treated with 20 mg/L forchlorfenuron, the parent compound and all 3 kinds of hydroxylated metabolites were successfully detected.

The established method is simple, rapid and accurate, and is suitable for the simultaneous determination and residue monitoring of forchlorfenuron and its hydroxylated metabolites in Actinidia chinensis Planch. It also provides a more comprehensive technical basis for dietary risk assessment of related compounds.

To achieve rapid and accurate detection of mercury ions (Hg²⁺) in tap water by utilizing the peroxidase-like catalytic activity of AuRu bimetallic nanozymes (AuRuNPs).

Using AuCl₃ and RuCl₃ as precursors, the AuRuNPs was synthesized in one step by allowing the reaction to stand in ethanol solvent at room temperature in the dark for 12 h. Then, the L-cysteine (Cys) was added to the system and co-incubated with the AuRuNPs to inhibit its peroxidase-like activity. Subsequently, the water sample to be tested was mixed with the above inhibition system, allowing Hg²⁺ to specifically chelate with Cys to release inhibition. Finally, the substrates 3,3’,5,5’-tetramethylbenzidine and H₂O₂ were added. After a 40 min reaction at room temperature, the absorbance at 652 nm was measured, and the concentration of Hg²⁺ was quantified using a standard curve.

Following condition optimization, a linear detection range of 1–100 μmol/L was achieved for Hg²⁺, with a limit of detection of 3.03 μmol/L. Good selectivity toward common interfering ions was demonstrated. In tests performed on actual tap water samples, spiked recoveries ranged from 97.16% to 98.50%, with a relative standard deviation was less than or equal to 4.75%.

This method is simple to operate, low in cost and strong anti-interference ability, providing a new strategy for the on-site rapid screening of Hg²⁺ in tap water.

To establish an improved sample pretreatment procedure combined with gas chromatography (GC) coupled with an electron capture detector (ECD) and gas chromatography-tandem mass spectrometry (GC-MS) for the determination of prochloraz and its metabolites in fruits and vegetables.

Prochloraz and its metabolites were extracted from samples using a solvent mixture based on anhydrous ethanol and dichloromethane. The extract was subjected to rotary evaporation, followed by hydrolysis with anhydrous magnesium sulfate in the presence of pyridine hydrochloride, re-extraction with dichloromethane, purification with sulfuric acid, and concentration. The final residue was reconstituted with a mixture of methyl tert-butyl ether and ascorbic acid-saturated acetone solution (9:1, V:V), filtered through a syringe filter and analyzed.

The spiked recoveries of prochloraz and its metabolites in fruits and vegetables were determined using the proposed method. The GC-ECD method exhibited recoveries ranging from 95% to 118%, with relative standard deviations of 3.95%–4.89% (n=6) and limit of detection of 0.01 mg/kg. The GC-MS method achieved recoveries of 92%–108%, with relative standard deviations of 3.39%–4.35%(n=6) and an limit of detection of 0.001 mg/kg.

Compared with the current national food safety standard GB 23200.121—2021 National standard for food safety food-Determination of residues of 352 pesticides and their metabolites in plant-derived foods-Liquid chromatography-tandem mass spectrometry, this method enables the analysis of prochloraz and its metabolite residues in fruits and vegetables within a shorter time frame while offering advantages in terms of sensitivity, accuracy and cost. It provides a reliable technical approach and research foundation for the detection of prochloraz and its metabolites in complex fruit and vegetable matrices.

To establish an isotope dilution high performance liquid chromatography-tandem mass spectrometry method for the quantitative analysis of N-phenylpropoxyphenyl carbodenafil in health foods.

The samples were ultrasonically extracted with methanol, and the extracts were centrifuged, filtered and then analyzed. Chromatographic separation was performed on a RP₁₈ column (2.1 mm×100 mm, 1.7 μm) used gradient elution with 2 mmol/L ammonium formate aqueous solution and acetonitrile as the mobile phase. Detection was carried out using electrospray ionization in positive ion mode with multiple reaction monitoring, and quantification was achieved using an isotope internal standard method.

N-phenylpropoxyphenyl carbodenafil showed good linearity in the range of 0.1–40.0 ng/mL, with a correlation coefficient greater than 0.995. The limit of detection was 0.005 mg/kg, and the limit of quantitation was 0.010 mg/kg. The recoveries at low, medium and high spiked levels ranged from 83.99% to 110.25%, with relative standard deviation (RSD) ranging from 3.1% to 13.1%. This method was applied to analyze 28 batches of collected samples, and none of them tested positive for N-phenylpropoxyphenyl carbodenafil.

This method is efficient, sensitive and accurate, effectively correcting matrix-induced ionization suppression in complex matrices, and is suitable for the qualitative and quantitative analysis of illegally added N-phenylpropoxyphenyl carbodenafil in health foods.

To investigate the residual dissipation behaviors and dietary risk of azoxystrobin and epoxiconazole in Oryza sativa straw, husk and brown rice using ultra performance liquid chromatography-tandem mass spectrometry.

The samples were directly extracted with acetonitrile aqueous solution, then vortexed and centrifuged. A certain amount of the supernatant was filtered and analyzed using ultra performance liquid chromatography-tandem mass spectrometry. Quantification was performed using the external standard method.

The limit of quantitation for azoxystrobin and epoxiconazole were both 0.05 mg/kg. The average recoveries of azoxystrobin and epoxiconazole were in the range of 91.9%–100.7%, respectively, with the relative standard deviations of 0.34%–4.19% at spiked levels from 0.05 mg/kg to 5.00 mg/kg. In contrasted to the traditional QuEChERS procedure, the proposed method eliminated the clean-up step, substantially decreased the usage of organic reagents, and enabled simpler and more rapid sample processing. The degradation dynamics of azoxystrobin and epoxiconazole residued in brown rice fitted the first-order kinetic equations, while the half-lives ranged from 1.04 to 17.54 d respectively. The highest residual amount of azoxystrobin and epoxiconazole in brown rice at 28 d after the last application were 0.26 mg/kg,0.44 mg/kg, which were lower than the maximum residue limit of 0.5 mg/kg established by China. The chronic dietary exposure risks for the general population, expressed as risk quotient, were 5.36% for azoxystrobin and 39.05% for epoxiconazole.

Application of 35% azoxystrobin, epoxiconazole suspension concentrate (containing 20% azoxystrobin and 15% epoxiconazole) according to the procedure established in this study will not cause unacceptable health risks to the general population via Oryza sativa consumption.