Volume 42, Issue 7 (2026)
Fundamental Research
Dynamic evolution law of volatile flavor components during the aging process of sauce-flavored Baijiu
Dai Jiahui, Wang Yanan, Kang Xiaoning, Dai Wenting, and Wang Shiping
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80644
[Objective］To investigate the aroma changes of sauce -flavored Baijiu during different aging periods, and to provide a theoretical basis for Baijiu aroma analysis and modern processing technology research.［Methods] Electronic nose, gas chromatography -mass spectrometry (GC-MS), and gas chromatography -ion mobility spectrometry (GC-IMS) were employed. Sauce -flavored Baijiu with different aging times (original liquor, 1-year aged, and 5-year aged) was used as the research objects. Combined with multivariate statistical methods, including principal component analysis (PCA) and orthogonal partial least squares -discriminant analysis (OPLS -DA), the differences in volatile flavor compounds of Baijiu with different aging times were analyzed.［Results］A total of 1 626 volatile compounds were detected in the three Baijiu samples. Based on the calculation of relative odor activity value (rOAV) and screening of compounds with rOAV≥1, 47 important volatile compounds were identified, including 1 amine, 6 alcohols, 2 aromatic hydrocarbons, 1 phenol, 1 halogenated hydrocarbon, 3 ethers, 10 aldehydes, 3 terpenoids, 5 ketones, 3 heterocyclic compounds, and 12 esters.［Conclusion］The aroma characteristics of Baijiu with different aging times are similar, but clear differences also exist. With increasing aging time, the contents of higher alcohols, aldehydes, and esters -contributing to a rich and delicate flavor -increase, while pungent and irritating substances decrease. As a result, the aroma of Baijiu becomes more stable and mellow, with a more complex aroma profile.
Effect of cultivation methods on volatile components in Morchella esculenta
Liu Ni, Jiang Bo, and Li Lang
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80586
[Objective] To comprehensively reveal the flavor and quality characteristics, and differences of Morchella esculenta under different cultivation methods, and systematically evaluate their volatile aroma components. [Methods] Qualitative and quantitative analyses are conducted on volatile aroma components in M. esculenta cultivated in greenhouses, under forests, and in caves in the vicinity of FAST by headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) techniques. The contribution of different components to the overall flavor is assessed by the relative odor activity value (ROAV) method. Based on this, principal component analysis and cluster analysis are conducted, achieving a comprehensive evaluation of the flavor characteristics of M. esculenta. ［Results] The GC-MS analysis results show that 1 201 volatile substances are detected in M. esculenta under the three cultivation methods, mainly including acid, alcohol, aldehyde, amine, aromatics, ester, ether, halogenated hydrocarbons, heterocyclic compounds, hydrocarbons, ketone, nitrogen compounds, phenol, sulfur compounds, and terpenoids. Among them, the relative content of heterocyclic compounds is the highest, ranging from 11.042% to 28.365%, followed by ester and aldehyde. Due to different cultivation methods, the relative content of various volatile components varies, with significant differences between most of them (P<0.05). The analysis results of the ROAV method show that the main volatile aroma components in M. esculenta under three cultivation methods are α, α, 4-trimethyl-3-cyclohexene-1-methylthiol, dihydro-2-methyl-3(2H)-furanone, 5-ethyl-3-hydroxy-4-methyl-2(5H)-furanone, and 1-nonen-3-one. Different cultivation methods result in variations in the volatile aroma components in various M. esculenta. The comprehensive evaluation results of principal component analysis and cluster analysis indicate that the cave cultivation method leads to the highest comprehens]ive score on the aroma quality of M. esculenta and the best aroma quality. ［Conclusion There are numerous types of volatile compounds in M. esculenta cultivated in greenhouses, under forests, and in caves in the vicinity of FAST, with significant differences in relative content. The main volatile aroma components vary with the cultivation method. Additionally, the best aroma quality is found in M. esculenta cultivated in caves.
Microwave-assisted enzymatic hydrolysis of Tibetan sheep blood protein and analysis of product characteristics
Yu Xilu, Gu Xuedong, Chen Yujin, Zhang Hongxin, and Ciren Danzhu
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2026.80023
[Objective] This study aims to utilize fresh Tibetan sheep blood as raw material, investigate the enhancing effect of microwave-assisted technology on enzymatic hydrolysis efficiency, and achieve high-value utilization of Tibetan sheep blood. [Methods] A microwave-assisted trypsin hydrolysis method is employed to enzymatically hydrolyze the proteins. The optimal hydrolysis conditions are established through single-factor experiments and response surface methodology. The resulting hydrolysates are characterized using scanning electron microscopy (SEM) and a fully automated amino acid analyzer.［Results］The optimal hydrolysis conditions are determined as follows: microwave temperature of 40 ℃, microwave time of 50 min, enzymatic hydrolysis time of 240 min, enzyme-to-substrate ratio of 6 000 U/g, microwave power of 348 W, hydrolysis pH of 10, hydrolysis temperature of 45 ℃, and substrate concentration of 11%. Under these conditions, the highest degree of hydrolysis reaches （26.38±0.75）%. The molecular weight distribution of the resultant small-molecule active peptides shows that fractions with molecular weight >5 000, between 5 000~1 000, and <1 000 account for>0.54%, 10.74%, and 88.72%, respectively.［Conclusion] The products obtained via microwave-assisted enzymatic hydrolysis exhibit excellent digestibility and absorption properties, and the composition of free amino acids after hydrolysis is more balanced. The microwave-assisted enzymatic hydrolysis method is therefore suitable for optimizing the process optimization of Tibetan sheep blood protein.
Safety & Inspection
Analysis of inorganic element content and health risk assessment of Ranunculi ternati radix from different origins
Li Juan, Geng Xiaotong, Yao Weijie, Zhou Tao, and Bi Jingjing
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80582
[Objective］The variations in inorganic element content and the safety of heavy metals and harmful elements in Ranunculi ternati radix from different origins were investigated.［Methods］The quantitative analysis of 24 elements in the samples was performed by inductively coupled plasma mass spectrometry (ICP-MS). Health risk assessment was conducted using estimated daily intake (EDI), target hazard quotient (THQ), and carcinogenic risk (CR). Principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) were used for origin identification analysis and differential element screening. [Results] All 25 Ranunculi ternati radix samples from different origins contain abundant macronutrients (K, Na, Ca, and Mg) and micronutrients (Fe, Cu, Zn, Cr, Mn, Ni, V, Co, Mo, and Se) essential for the human body. The contents of heavy metals and harmful elements Pb, Cd, As, Hg, and Cu are 0.630.51, 0.050.11, 0.260.62, 0.010.10, and 32.96~167.25 mg/kg, respectively. Among them, the Cu content exceeds the limit for botanical drugs in the Chinese Pharmacopoeia (2020 edition). In terms of health risk assessment, the EDI analysis reveals that the estimated maximum daily intakes of Cr, Al, Ni, Pb, As, and Cu for adults and children from Ranunculi ternati radix in all or some origins exceed 10% of the provisional tolerable daily intake (PTDI), with some exceeding the PTDI value, indicating health risks. In the THQ analysis, the target hazard quotient values of Cr, Al, Cu, and As for adults and children from Ranunculi ternati radix in all or some origins exceed the standard THQ, indicating health hazard risks. In the CR analysis, the potential carcinogenic risk indices of Cd and As, as well as the total potential carcinogenic risk index of the three heavy metals Cd, As, and Pb, range from 1×10−6 to 1×10−4, indicating potential carcinogenic risks. The PCA identifies elements such as V, Al, Cs, Co, As, Fe, Mn, Tl, Cr, Pb, K, Ni, Sr, Cu, Ag, Cd, Hg, Zn, Ca, Na, Mo, Mg, and Se as the characteristic elements of Ranunculi ternati radix. The PLS-DA identifies four elements, including K, Mg, Fe, and Al, as effective traceability indicators for the origin of Ranunculi ternati radix.［Conclusion］The established method can rapidly and accurately analyze the inorganic element contents in Ranunculi ternati radix. When Ranunculi ternati radix is ingested for a long term, attention should be paid to controlling the dosage and duration of administration to reduce the health risks caused by elements such as Cr, Al, As, Cu, Ni, Pb, and Cd.
Rapid detection of viable Salmonella based on specific phage infection combined with fluorescent RPA
Liu Daofeng, Zhai Yujie, Tan Yucheng, Shan Shan, Lu Jun, and Zhong Ziqing
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80609
[Objective] To establish a rapid detection method for viable Salmonella based on specific phage infection and recombinase polymerase amplification (RPA) in response to the key challenge that traditional molecular biological detection methods have difficulty in conveniently distinguishing between viable and non-viable foodborne pathogens. [Methods] Taking advantage of the characteristic that O-1 phage only proliferates in viable bacteria, the phage is added to the enriched sample. After further incubation, total DNA is extracted. Fluorescent RPA is used to determine whether the phage has significantly proliferated, so as to judge the presence of viable Salmonella in the original sample. [Results] After optimization, the optimal detection conditions are as follows: 100 μL of O-1 phage with a concentration of 3×105 PFU/mL is added, and the infection and proliferation time is 3 hours. The detection limit of the method for phage DNA is |0.07 fg/μL, and that for viable Salmonella is 1.58×102 CFU/mL. The intra-generic inclusivity of the method is 100% when testing 37 Salmonella strains of different serotypes, and the inter-generic specificity is 100% when testing 17 non-Salmonella strains. [Conclusion] The method utilizes the characteristic that phages only rapidly proliferate in viable host bacteria, enabling highly sensitive and specific detection of viable Salmonella within 4 hours without a PCR thermal cycler. The method is suitable for on-site rapid screening and identification of viable Salmonella in food production and circulation processes, providing a new approach for the on-site detection of viable Salmonella in food.
Establishment of an indirect competitive ELISA for sulfadimethoxine
Han Lu, Huang Mingyue, Yu Xiang, Li Sijia, Cao Jinbo, Wang Yao, and Kang Huaibin
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80598
[Objective] To establish an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) for the detection of sulfadimethoxine (SDM) in animal-derived foods. [Methods] An artificial antigen is synthesized by conjugating SDM with carrier proteins by the diazotization method. A highly sensitive antibody against SDM is prepared by immunizing animals. Based on this, an ic-ELISA is established and the detection system is optimized. Its detection performance is characterized, and spiked recovery tests are carried out. [Results] When the concentration of the coating antigen is 0.500 μg/mL, the dilution ratio of the horseradish peroxidase-labeled goat anti-rabbit secondary antibody is 1:5000, the reaction time of the primary antibody is 15 min, the reaction time of the secondary antibody is 30 min, and the chromogenic reaction time is 10 min, the established ic-ELISA exhibits an IC50 of 9.33 ng/mL, a detection range of 0.76~114.82 ng/mL, and a limit of detection of 0.74 ng/mL, with good precision and specificity, and satisfactory spiked recovery rates in milk, chicken, and pork samples. [Conclusion] This method can be applied to the sensitive, precise, specific and accurate detection of SDM residues in real samples of milk, chicken, and pork, providing an effective means for efficient on-site screening.
Authenticity identification of camellia seed oil based on gas chromatography and chemometrics
Li Jingyan, Li Qin, Han Bo, and Zhang Ruixue
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.81173
[Objective] To establish a method for authenticity identification of camellia seed oil. [Methods] The fatty acid composition of camellia seed oil and six common vegetable oils are determined by gas chromatography. Principal component analysis (PCA) is employed to explore the distribution patterns of fatty acids among the vegetable oils and to screen for potentially adulterated oils. Partial least squares discriminant analysis (PLS-DA) is applied to establish a model between fatty acid profiles and actual adulterated oils. Finally, multiple stepwise linear regression analysis is used to establish quantitative analysis models for adulteration in camellia seed oil. [Results] Among the six common vegetable oils, olive oil and peanut oil exhibit fatty acid compositions most similar to that of camellia seed oil, and are therefore selected as potential adulterants. The PLS-DA model could discriminate adulterated oils with adulteration levels no lower than 5%, and identify characteristic fatty acids for olive oil adulteration (palmitic acid, behenic acid, linoleic acid, palmitoleic acid and stearic acid) and for peanut oil adulteration (oleic acid, linoleic acid and palmitic acid). The quantitative models established by stepwise linear regression for olive oil and peanut oil adulteration in camellia seed oil achieve correlation coefficients (R2) greater than 0.9 for both models. The limits of detection (sensitivities) for the two models are 5% and 2%, respectively, and the method repeatabilities range from 0.7% to 6.0% and from 0.8% to 3.3%, respectively. The errors between predicted and actual values range from −1.93% to 2.08% and from −0.79% to 0.15%, respectively. [Conclusion] This comprehensive technical strategy, encompassing screening, qualitative discrimination, and quantitative analysis, provides a complete solution for the authenticity assessment of camellia seed oil.
Migration volume determination and migration patterns of 11 antioxidants from degradable polylactic acid straws
Luo Minting, Wu Zhihang, Hu Tengxin, and Xu Qingpeng
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80697
[Objective] To establish a method for authenticity identification of camellia seed oil. [Methods] The fatty acid composition of camellia seed oil and six common vegetable oils are determined by gas chromatography. Principal component analysis (PCA) is employed to explore the distribution patterns of fatty acids among the vegetable oils and to screen for potentially adulterated oils. Partial least squares discriminant analysis (PLS-DA) is applied to establish a model between fatty acid profiles and actual adulterated oils. Finally, multiple stepwise linear regression analysis is used to establish quantitative analysis models for adulteration in camellia seed oil. [Results] Among the six common vegetable oils, olive oil and peanut oil exhibit fatty acid compositions most similar to that of camellia seed oil, and are therefore selected as potential adulterants. The PLS-DA model could discriminate adulterated oils with adulteration levels no lower than 5%, and identify characteristic fatty acids for olive oil adulteration (palmitic acid, behenic acid, linoleic acid, palmitoleic acid and stearic acid) and for peanut oil adulteration (oleic acid, linoleic acid and palmitic acid). The quantitative models established by stepwise linear regression for olive oil and peanut oil adulteration in camellia seed oil achieve correlation coefficients (R2) greater than 0.9 for both models. The limits of detection (sensitivities) for the two models are 5% and 2%, respectively, and the method repeatabilities range from 0.7% to 6.0% and from 0.8% to 3.3%, respectively. The errors between predicted and actual values range from −1.93% to 2.08% and from −0.79% to 0.15%, respectively. [Conclusion] This comprehensive technical strategy, encompassing screening, qualitative discrimination, and quantitative analysis, provides a complete solution for the authenticity assessment of camellia seed oil.
Determination of five fluorescent whitening agents in prepared dishes by gel permeation chromatography-high performance liquid chromatography
Li Bingbing, Wang Chunlei, Huang Zhenzhen, Dai Li, and Wang Kun
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80528
[Objective] To establish a method for the determination of five fluorescent whitening agents (FWAs) in prepared dishes using gel permeation chromatography combined with high-performance liquid chromatography (GPC-HPLC). [Methods] The prepared dish samples were homogenized, ultrasonically extracted with acetonitrile, purified and reconstituted by GPC, then filtered before being analyzed by HPLC. The separation was performed on a Waters Symnetry Shield PR-C18 column (4.6 mm ×250 mm, 5.0 µm) using acetonitrile and water as the mobile phase with gradient elution. [Results] The five FWAs in the prepared dishes showed good linearity within the range of 2~500 µg/L, with correlation coefficients greater than 0.999. The limits of detection (LODs) ranged from 0.016 to 0.233 µg/kg, and the limits of quantification (LOQs) ranged from 0.05 to 0.78 µg/kg. At three spiked levels (low, medium, and high), the recoveries for the five FWAs were between 75.3% and 97.1%, with relative standard deviations (RSDs) ranging from 0.3% to 5.0%. [Conclusion] The developed method is accurate, reliable, and highly sensitive, making it suitable for the determination of FWAs in prepared dishes.
Determination of migration level of 4-methyl- 1-pentene and 1-decene from food contact materials using headspace-gas chromatography
Liu Afang, Chen Ranbing, Li Zheng, Kang Feng, and Zhao Jinyao
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2026.80300
[Objective] This study aims to establish an analytical method for detecting the migration levels of 4-methyl-1-pentene and 1-decene monomers from food contact materials into four food simulants, including 4% acetic acid, 10% ethanol, 20% ethanol, and 50% ethanol. [Methods] Chromatographic columns of different polarities and specifications are compared to select the optimal column. The headspace equilibrium temperature and equilibrium time are optimized using peak area as the evaluation index. Methodological validation is performed by conducting recovery experiments at low, medium, and high spiking levels using the soaking solutions of the negative sample of the four food simulants as the matrix, and the recoveries and relative standard deviations of the migration levels of target analytes are determined and calculated. [Results] The optimal experimental conditions are as follows: HP-5 capillary chromatographic column (30 m×0.25 mm, 1 μm), headspace equilibrium temperature of 80 ℃, equilibrium time of 40 min, detection by flame ionization detector (FID), quantification by the external standard method. Both target compounds exhibit good linearity in the concentration range of 0.01~0.1 mg/L, with correlation coefficients all greater than 0.995. The limits of detection (LOD, S/N=3) range from 0.000 1 to 0.002 mg/kg, and the limits of quantification (LOQ, S/N=10) range from 0.000 3 to 0.006 mg/kg. The spiked average recoveries range from 81.0% to 109%, with relative standard deviations (RSD, n=6) of 1.3%~9.8%. [Conclusion] This method is convenient and sensitive, with satisfactory accuracy and precision. It is suitable for the determination of 4-methyl-1-pentene and 1-decene monomer migration levels in plastic materials for food contact.
Food Equipment & Intelligent Manufacturing
A surface defect detection model for fused images of fruits based on improved ResNet 18
Si Haiping, Zhao Wenrui, Zhao Yuyang, Li Tingting, Fernado Bacao, and Li Yanling
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80635
[Objective] To enhance the accuracy of detecting fruit surface defects caused by minor mechanical friction during transportation. [Methods] A surface defect detection model for fused images of fruits based on improved ResNet 18 is proposed. To address the challenge of multi-scale feature extraction, the model incorporates a MELA module designed to capture image details more comprehensively. Additionally, an energy function-based regularization loss function is introduced to collaboratively optimize the training process alongside the cross-entropy loss function. Furthermore, a transfer learning strategy is employed to mitigate overfitting. [Results] Experimental results demonstrated that the improved model exhibits exceptional performance in fruit surface defect detection tasks, achieving the accuracy, precision, recall, and F1 score as high as 99.53%, 99.60%, 99.58%, and 99.58%, respectively. [Conclusion] The surface defect detection model for fused images of fruits based on improved ResNet 18 significantly enhances the detection accuracy and is suitable for surface defect detection in fused images of fruits.
Non-destructive detection of pork loin freshness based on the YOLO v 11 model
Deng Zhonghui and Xie Wei
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80686
[Objective] To develop an intelligent method for non-destructive recognition of pork loin freshness based on computer vision technology, which is to be achieved by establishing a classification model for accurate, fast, and non-destructive detection of pork freshness in the cold chain industry. [Methods] A classification detection model is proposed based on the YOLO v11 architecture. First, total volatile basic nitrogen (TVB-N) content and pH values are measured before the meat samples are divided into three categories: "fresh", "less fresh", and "spoiled". A dataset of 4 680 high-resolution images is constructed (generated from 1 247 original images enhanced through operations such as rotation, flipping, cropping, brightness adjustment, and blurring). Then, the dataset is divided into training, validation, and test sets in a 6∶2∶2 ratio. Utilizing a transfer learning strategy, the YOLO v11 model with pre-trained weights is initialized in the PyTorch framework and trained using the SGD optimizer (learning rate of 0.01). Finally, the model established is compared with six mainstream models: DenseNet 161, EfficientNet_b2, MobileNet_v2, ResNet 50, ShuffleNet_v2_x1, and ViT_base_patch16_224. [Results] The YOLO v11 model achieves excellent performance, with an overall classification precision of 1.000, significantly outperforming the best baseline model, ViT_base_patch16_224. Additionally, the proposed model demonstrates significant advantages over other models in both F1 score and accuracy metrics. [Conclusion] In this study, the YOLO v11 model is successfully applied to the non-destructive detection of pork loin freshness. With high-precision generalization capabilities, the proposed instance classification method achieves a detection rate of 1.000 for spoiled meat and ensures food safety. With an inference speed of 12 ms, this model is suitable for real-time non-destructive detection in production lines. Additionally, exhibiting a strong generalization ability, the model can evenly recognize multiple levels of freshness, with classification accuracy greater than 98% for each category.
Storage Transportation & Preservation
Application of slow-release plant essential oil preservative combined with electron beam irradiation in the preservation of Shanghai sand pears (Pyrus pyrifolia Nakai )
Yue Ling, Lei Lei, Kong Qiulian, Zheng Qi, and Yan Weiqiang
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2026.80573
[Objective] To investigate the regulatory effects of a composite preservation technology combining slow-release plant essential oil (SPEO) with electron beam irradiation on the storage quality and physiological metabolism of Shanghai sand pears (Pyrus pyrifolia Nakai). [Methods] The fruits of Shanghai sand pear variety 'Cuiguan' are used as test materials. The experiment is conducted with four groups: control, 0.5 kGy electron beam irradiation, SPEO, and 0.5 kGy electron beam irradiation + SPEO. During storage, quality parameters including fruit firmness, weight loss rate, total soluble solids (TSS) content, titratable acid content, and vitamin C (VC) content, as well as physiological metabolism indicators such as respiratory rate and polyphenol oxidase (PPO) activity, are measured to evaluate preservation performance. [Results] Compared with the control group, all treatments effectively delay fruit quality deterioration. The 0.5 kGy electron beam irradiation + SPEO treatment demonstrates the best performance in maintaining fruit firmness and achieves the lowest weight loss rate after 70 days of storage, which is significantly lower than that of the control. This combined treatment delays the decline in TSS content while maintaining higher titratable acid content and VC content, significantly outperforming other treatments. Furthermore, the 0.5 kGy electron beam irradiation + SPEO treatment delays and reduces the respiratory peak and significantly inhibits the peak PPO activity, effectively delaying fruit senescence and browning. [Conclusion] The combination of 0.5 kGy electron beam irradiation and SPEO exhibits a significant synergistic effect, effectively delaying pear browning and senescence and achieving optimal comprehensive preservation performance.
Shrimp freshness indicator film based on grape seed proanthocyanidin/curcumin
Li Wenjing, Wang Hui, and He Mingxing
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80698
[Objective] To develop a shrimp freshness indicator film with good amine responsiveness and stability for the rapid and non-destructive detection of shrimp quality changes. [Methods] Using sodium carboxymethyl cellulose and starch as film-forming substrates, indicator films were prepared with grape seed proanthocyanidins, curcumin, and their mixtures as indicators. The responses of the three indicator films to aqueous solution pH and trimethylamine were compared. The detection sensitivity and storage stability of the mixed indicator film were further evaluated. The indicator film was then applied to monitor the freshness of Litopenaeus vannamei, and the correlation and kinetics between total volatile basic nitrogen (TVB-N) values of shrimp and the color difference (ΔE) of the indicator film were analyzed. [Results] The mixed indicator film exhibited high sensitivity to trimethylamine and good storage stability at different temperatures. Under storage conditions of 4, 25, and 37 ℃, the TVB-N value of shrimp was positively correlated with the ΔE value of the indicator film, with correlation coefficients all greater than 0.98. According to the Arrhenius equation, the activation energies for changes in shrimp TVB-N and the ΔE of the indicator film were 52.78 and 50.61 kJ/mol, respectively, showing good agreement. [Conclusion] The color change of the indicator film can maintain a similar variation trend with the TVB-N value of shrimp at different temperatures, thereby indicating shrimp quality and demonstrating good application prospects.
Nutrition & Activities
Effect of lotus leaf powder addition on whole wheat dough characteristics and whole wheat bread quality
Chen Rui and Gong Lingxiao
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80414
[Objective] To determine the optimum addition of lotus leaf powder in whole wheat flour, thus improving the nutritional value of whole wheat bread while maintaining high quality. [Methods] Rapid viscosity analyzer, rheometer, and texture analyzer are employed to explore the pasting properties of the composite flour, the rheological characteristics of the dough, and the texture properties of the bread. Additionally, the effect of lotus leaf powder on the quality of whole wheat bread is evaluated using a colorimeter, sensory evaluation, and in vitro digestion evaluation. [Results] The analysis reveals that as the lotus leaf powder addition is increased, a significant decrease occurs in the pasting profile of the composite flour, as well as the elastic modulus and viscous modulus of the whole wheat dough. However, when the addition is ≤2%, no significant change is observed in the color, specific volume, texture properties, or sensory evaluation of the lotus leaf whole wheat bread. Furthermore, an addition of 1% to 5% lotus leaf powder increases DPPH free radical scavenging activity by 10.13% to 30.59%, ABTS+ free radical scavenging activity by 39.27% to 198.94%, and ferric ion reducing power by 18.67% to 77.57% in the digestive fluids of whole wheat bread. [Conclusion] When lotus leaf powder addition is controlled within 2%, the quality and consumer acceptability of whole wheat bread can be ensured, while antioxidant properties can be imparted to the bread.
Effect of brewing methods on colloidal particle properties and antioxidant characteristics of coffee
Gao Guanzhen, Rao Pingfan, Han Cheng, Wang Huiqin, and Shan Yunhui
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.81202
[Objective] To investigate the effects of three typical brewing methods - hand drip, French press, and Turkish coffee - on the chemical composition, colloidal structure, and antioxidant activity of coffee, and to elucidate the mechanism of colloidal particles in the delivery of bioactive compounds. [Methods] Three types of coffee samples are prepared using the respective brewing methods. Their physicochemical components are determined and colloidal properties are characterized. The true solution phase and colloidal phase are separated by ultrafiltration, and their in vitro chemical and intracellular antioxidant activities are comparatively evaluated. [Results] Turkish coffee exhibits the highest extraction yield, but thermal induction causes colloidal aggregation. Hand drip forms a homogeneous nanoscale colloidal system, while French press forms micron- and nanoparticles with a lipid-based skeleton. Ultrafiltration experiments confirm the existence of matrix masking and antagonistic effects in the coffee system. Antioxidant evaluation reveals that Turkish coffee exhibits the highest in vitro chemical antioxidant activity, whereas hand drip and French press demonstrate superior bioavailability in cellular models, attributed to the nanoscale size effect or surface hydrophobic properties of their colloids, respectively. [Conclusion] Brewing methods determine the bioavailability of bioactive compounds by regulating the particle size, composition, and surface properties of colloidal particles. In addition to compound concentration, the colloidal microstructure is a key factor in enhancing the intracellular antioxidant efficacy of coffee.
Development & Application
Extraction process optimization of Dunaliella spp. protein and its physicochemical properties
Wang Xiaochen, Zhang Wei, Jing Yongkang, Xing Fengjie, Zhang Guodong, and Zheng Xin
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80565
[Objective] Using Dunaliella spp. powder as the raw material, to explore the effect of pH value, alkali dissolution temperature, alkali dissolution time, and solid-liquid ratio on Dunaliella spp. protein extraction. [Methods] The optimal conditions are screened by single-factor experiments. Response surface experiments are designed by the Box-Behnken method to determine the optimal extraction process parameters for Dunaliella spp. protein with the Dunaliella spp. protein extraction rate as the indicator. Additionally, the group composition, secondary structure, amino acid composition, and functional properties of Dunaliella spp. protein are determined. [Results] The optimal extraction process conditions for Dunaliella spp. protein is pH 10.54, alkali dissolution temperature 51 ℃, alkali dissolution time 2.1 h, and a solid-liquid ratio of 1:206 (g/mL). Under these conditions, the extraction rate of Dunaliella spp. protein is 52.98%. At 50 ℃, Dunaliella spp. protein exhibits the highest water and oil holding capacity. At a mass fraction of 0.6%, Dunaliella spp. protein exhibits the highest foaming property (40%), foam stability (62.5%), emulsifying property (62%), and emulsifying stability (66%). Structural analysis shows that the secondary structure of Dunaliella spp. protein is mainly β-sheet (26.79%), with essential amino acids accounting for 32.94%, and hydrophobic amino acids accounting for 39.52%. [Conclusion] The optimized extraction process for Dunaliella spp. protein can significantly increase protein extraction rate.
Dynamic changes of major non-volatile components during Gongfu black tea processing
Deng Ming, Chen Liang, Liu An, Wei Dongning, Wu Wenliang, Wu Xiaofen, and Qi Hui
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80580
[Objective] To investigate the dynamic changes in the major non-volatile chemical components during the processing of Jianghua Kucha 21-3 Gongfu black tea. [Methods] Fresh one-bud-two-leaf autumn tea leaves of Jianghua Kucha 21-3 were used as raw materials. Samples at different processing stages were obtained by liquid nitrogen pre-freezing and freeze-drying. The mass fractions of water extract, tea polyphenols, catechins, theaflavins (TFs), thearubigins (TRs), theabrownins (TBs), caffeine, theanine, free amino acids, and soluble sugars were determined. Additionally, sensory evaluation was conducted on Gongfu black tea processed with different fermentation durations. [Results] During processing, the mass fraction of water extract in Jianghua Kucha 21-3 Gongfu black tea gradually decreased, reaching (39.19±0.30) g/100 g after drying. The mass fractions of tea polyphenols, catechins, and theanine also decreased progressively, with rapid declines occurring during rolling and the early stage of fermentation. In contrast, the mass fractions of TFs and TRs increased sharply during rolling and early fermentation, reaching maximum values at 2 h and 6 h of fermentation, respectively, at (1.35±0.02) g/100 g and (7.22±0.54) g/100 g. The mass fraction of free amino acids reached its maximum at 3 h of fermentation and then gradually decreased, while the mass fraction of caffeine remained relatively stable throughout the processing. Sensory evaluation revealed that fermentation duration had little effect on the appearance of Gongfu black tea but significantly influenced its internal quality. When fermented for 3~4 h, Jianghua Kucha 21-3 Gongfu black tea exhibited a mellow and brisk taste with a bright red liquor, indicating superior quality. [Conclusion] The optimal fermentation time for Jianghua Kucha 21-3 Gongfu black tea should be controlled at 3~4 h.
Effects of various extraction methods on the performance of corn fiber gum-pea protein composite gels
Wu Chenglong, Jiang Zhili, Huang Lilin, Tang Leiming, and Sun Xiaohong
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80631
[Objective] This study aims to investigate the effects of three extraction methods - alkaline extraction, enzymatic extraction, and acid extraction - on the properties of corn fiber gum (CFG)-pea protein composite gels. [Methods] CFG was extracted from corn bran using the three methods. The gel strength, water-holding capacity, rheological properties, and microstructure of the CFG-pea protein composite gels are evaluated. [Results] The CFG extracted by enzymatic extraction increases the gel strength of pea protein gels from (27.20±2.45) g to (65.80±2.67) g, and the water-holding capacity from (40.60±3.40)% to (75.80±5.10)%. Additionally, it forms a more compact and ordered network structure with pea protein, demonstrating superior viscoelasticity. In contrast, the CFG extracted by alkaline and acid extraction contributes less to the composite gel properties compared with that extracted by enzymatic extraction. [Conclusion] The CFG-pea protein composite gel prepared with enzymatically extracted CFG exhibits the best overall performance.
Effects of extraction methods on the composition and physicochemical properties of flavonoids from Lycium barbarum leaves
Li Juanxia, Li Jianxin, Gao Jianying, Mai Wenting, Fan Yanli, Ma Jinchao, and Meng Xuemei
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80632
[Objective] To investigate the effects of different extraction methods on the efficacy, chemical composition, and functional group characteristics of flavonoids in Lycium barbarum leaves. [Methods] This study comparatively analyzes the effects of three methods - ultrasound-assisted ethanol extraction (UAE), microwave-assisted ethanol extraction (MAE), and aqueous two-phase system (ATPS) - on the yield, composition, and in vitro antioxidant activity of flavonoids from L. barbarum leaves. [Results] UAE and MAE achieve the highest yield of flavonoids from dried L. barbarum leaves. The main components are rutin, quercetin, chlorogenic acid, and kaempferol. The antioxidant capacity of the flavonoid extract from dried L. barbarum leaves is significantly higher than that of fresh samples, and the UAE extract has the highest DPPH radical scavenging rate (84.31%) and the strongest ferrous ion-reducing ability (26.23%). [Conclusion] The dissolution efficiency of flavonoids varies under different extraction methods, and there is a significantly positive correlation between the flavanol structure and antioxidant activity.
Numerical simulation of humidity field in Baijiu fermentation rooms and influencing factors
Hao Qi, Shi Yan, Yang Zhengquan, Lin Chunsong, Xu Guangqi, and Wen Enhan
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80573
[Objective] To investigate the effects of ventilation conditions and Daqu stacking methods in the fermentation room on the humidity levels at various points within the room. [Methods] A three-dimensional unsteady gas-solid coupling model of a small-scale fermentation room is established. Then, the humidity field variation patterns in the room are analyzed using the height of the humidifying air supply outlet (H), the interlayer spacing of fermentation racks (h), and the gap between fermentation piles (δ) as variables. Additionally, multi-objective optimization is performed based on response surface methodology (RSM) and the non-dominated sorting genetic algorithm II (NSGA-II). [Results] H, h, and δ all significantly affect the humidity field, with h exerting the highest influence weight. Parameter optimization yields the Pareto optimal front: H=492 mm, h=167 mm, and δ=140 mm. Compared with the original model, the humidity regulation rate is increased by 31.9%, and the humidity uniformity index is improved by 11.82% after optimization. [Conclusion] The collaborative optimization of the fermentation room layout parameters H, h, and δ can effectively improve the regulation of the solid-state fermentation environment, significantly enhancing both the humidity regulation rate and uniformity.
Peeling effect of three-dimensional turbulent flexible friction for small yellow ginger
Sun Fang, Lu Kuirong, and Jiang Shuiquan
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2026.60080
[Objective] Aiming at the industrial bottleneck that the industrial peeling of small yellow ginger cannot balance high peel removal rate and low flesh damage rate due to its irregular shape, dense branches, thin and tender peel, a piece of peeling equipment based on three-dimensional turbulent flexible friction is developed. [Methods] Small yellow ginger is taken as the test material. With peel removal rate and flesh retention rate as evaluation indicators, single-factor and L9(34) orthogonal experiments are carried out to optimize three key parameters: processing time, material-water ratio, and stirring speed. Origin is used for data statistics and analysis. [Results] The influences of factors follow the trend of processing time > stirring speed > material-water ratio. The optimal parameters are determined as follows: processing for 6 min, a material-water ratio of 1∶2, and a stirring speed of 35 r/min. Under the above conditions, the peel removal rate, the flesh retention rate, and the processing capacity reach 98.12%, 95.86%, and 2.11 t/h, respectively. Compared with brush mechanical peeling and chemical alkali peeling, the proposed equipment and supporting process present the advantages of high peeling efficiency, low flesh damage, no chemical residue, and favorable environmental performance. [Conclusion] The coordination of equipment innovation and process optimization can realize efficient and low-damage industrial peeling of small yellow ginger and provide references and technical support for the green processing of irregular fruits and vegetables with thin peels.
Design and application of low-temperature heat pump belt drying technology in soy sauce residue drying process
Liu Shumo, Wang Liangliang, Qi Yan, Luo Zhiqiang, and Cao Lei
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80479
[Objective] To address key issues in conventional soy sauce residue drying processes, including high energy consumption, severe equipment corrosion, and the susceptibility of heat-sensitive nutrients to degradation, a novel integrated drying system was designed and developed to achieve high efficiency, energy savings, and reliable product quality. [Methods] The system integrates key technologies such as spiral air-duct drying and two-stage dust removal. Based on the reverse Carnot cycle principle of a heat pump, a low-temperature drying environment of 40~75 ℃ was established, with the aim of reducing energy consumption while maximizing the retention of the material’s original quality. [Results] The system achieved a processing capacity of 130 t/d (initial moisture content of 32%) and was able to consistently reduce the moisture content of soy sauce residue to below 15%. The specific moisture extraction rate reached 3.3 kg/(kW·h), demonstrating significant energy-saving performance. Physicochemical analysis confirmed that the retention rate of key nutrients, such as crude protein, exceeded 95% after drying. The dried residue exhibited stable properties, met food-grade standards, and could be directly used for subsequent resource utilization. [Conclusion] The integrated low-temperature heat pump belt drying system developed in this study effectively resolves the conflict between energy efficiency and product quality in soy sauce residue drying. It provides a reliable technical solution for the efficient and high-value utilization of high-salt, high-moisture, and heat-sensitive by-products.
Effect of hot air drying process on the cracks and quality of jujubes
Hu Linbin, Li Lin, Wang Long, Hu Can, and Yi Xiaokang
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80493
[Objective] To investigate the crack occurrence in jujubes under different hot air drying conditions and the resulting quality differences. [Methods] Jujubes of Xinjiang are taken as the research objects. Based on hot air drying technology, three drying temperature and wind speed levels are set up to explore the drying characteristics and quality changes of crack-free and cracked jujubes under different drying conditions. [Results] Under hot-air drying conditions, the drying rate can be accelerated by increasing drying temperature and wind speed. Compared to crack-free jujubes, cracked ones are prone to moisture loss, thus requiring shorter drying times. Increases in temperature and wind speed enhance the effective moisture diffusion coefficient. The initial crack rate of fresh jujube samples is between 35% and 55%. The newly added crack rates of crack-free jujubes after drying at 65 ℃ (with a fixed air drying wind speed) and 2.0 m/s (with a fixed drying temperature) are 30% and 20%, respectively. Under the same conditions, no new cracks occur in the cracked jujubes after drying. As drying temperature and wind speed are increased, total sugar, total acid, and ascorbic acid content, as well as L*, a*, and b* values decrease, while reducing sugar content and △E show the opposite trend. [Conclusion] Increased drying temperature and drying wind speed shorten the drying time of jujubes and influence crack occurrence, but the resulting cracks do not affect jujube quality.
Advances
Research progress on plant-derived metal ion chelating peptides
Pei Hanzhe, Zhao Hongfei, Zhou Jiahua, Zhang Bolin, and Chen Yonghao
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80280
Mineral element deficiency can cause many health problems. Traditional metal element supplements have many shortcomings. Food-derived metal element supplements have gradually become a research hotspot. Plant-derived polypeptides have significant advantages in terms of cost and raw material sources. Chelating peptides formed by chelating metal ions with plant-derived polypeptides have the physiological activity of peptides and the functional characteristics of metal elements, which makes them relatively ideal nutritional supplements, showing broad development prospects. This paper collects relevant research reports at home and abroad, and sorts out the preparation process, chelation mechanism and characteristics, and biological activity of plant-derived metal ion chelating peptides. The paper provides an outlook on the development trend and large-scale application prospect of plant-derived metal ion chelating peptides in basic research, application scenarios, and industrial transformation.
Research advances in rice bran oil bioactive components and antioxidant technologies
Tu Yue, Guo Xiongchang, Zhang Wenhan, Cai Lichuang, and Liu Jianping
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80576
Rice bran oil is a unique natural edible oil with healthy benefits and a reasonable fatty acid composition. Containing natural antioxidant components including phytosterols, oryzanol, tocotrienols, and squalene, rice bran oil is characterized by high nutritional value, diverse physiological functions, and excellent frying performance, thus demonstrating broad application potential. This study reviews the research advances in the bioactive components, physiological functions, factors influencing oxidative stability, and antioxidant technologies of rice bran oil, while providing prospects for future development.
Research progress on effect of salt on pickling vegetable quality
Qi Kai, Li Ziyan, Cheng Wenbo, Fan Mingcong, Zuo Daoxi, Li Yan, Wang Li, and Zhang Wenbin
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80718
Vegetable pickling is a time-honored food preservation and processing method, in which salt (primarily sodium chloride) plays an irreplaceable and core role. This paper systematically reviews the multidimensional effects of curing salt on vegetable quality. It comprehensively covers preservation mechanisms, textural transformations, the formation and conversion of flavor compounds, color stability, and nutritional value changes. Specifically, this article analyzes the decisive role of salt concentration gradients in final product characteristics. Furthermore, it examines the challenges posed by the low salinity, including microbial safety risks, textural deterioration, and flavor imbalances, while proposing corresponding strategies.
Research progress in the extraction and purification processes and biological activities of flavonoids from Cuscutae Semen
Li Renxin, Xiong Ying, and Song Hui
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80909
Cuscutae Semen is a Chinese herbal medicine and a raw material for health foods in China, with flavonoids being a group of its main functional components. This article provides a systematic review of the extraction and purification techniques - reflux, ultrasonic, Soxhlet, microwave-assisted, flash, enzymatic hydrolysis, and supercritical CO2 extraction methods - of flavonoids from Cuscutae Semen. Furthermore, it elaborates on the biological activities such as reproductive protection, anti-tumor effect, anti-oxidative stress effect, liver and kidney protection, and immune regulation of flavonoids from Cuscutae Semen, as well as their related mechanisms. Moreover, this paper makes an outlook on the development prospects of flavonoids in Cuscutae Semen in terms of green intelligent extraction, mechanism analysis, and applications.
Packaging & Design
Heat transfer analysis and packaging optimization design of self-heating rice
Sun Haowen, Li Huan, Wu Xiaomeng, and Mao Like
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.80551
[Objective] To further understand the influence of the heat transfer process on the quality of self-heating foods and improve the heating rate of existing self-heating rice products. [Methods] A combination of virtual simulation and experimental methods was used to analyze the actual temperature variations during the heating process of self-heating rice and the effects of heat transfer on rice texture. A three-dimensional heat transfer model of self-heating rice was established using COMSOL software to investigate the heat transfer process, and the packaging design of self-heating rice was optimized with the objective of maximizing the heating rate. [Results] After reheating and cooling at 20 ℃ for 90 min, differences in textural properties were observed among different layers of self-heating rice. The rice in the middle layer showed higher chewiness and better overall texture, whereas the springiness, cohesiveness, and chewiness of the bottom layer rice were significantly reduced. The established three-dimensional heat transfer model accurately described the temperature changes during the heating process of self-heating rice. In addition, for self-heating rice with the same volume, optimization of packaging dimensions and length-to-width parameter combinations (with a length of 133.49 mm and a width of 120 mm) shortened the heating time by 387 s; The use of a bowl-shaped package (with a top diameter of 273 mm and a bottom diameter of 200 mm) shortened the heating time by 194 s; And the application of a novel aluminum foil-bottom packaging material shortened the heating time by 251 s. Compared with the original commercial packaging, all these optimization strategies significantly improved the heating performance of self-heating rice. [Conclusion] The combination of virtual simulation and experimental methods used in this study can intuitively describe the heat transfer performance of self-heating rice, and optimization of self-heating rice packaging can effectively improve the heat transfer rate.
Innovative application of intangible cultural heritage narrative design in agricultural food packaging
Chen Yanan and Chen Bingyan
Date posted: 7-25-2026
DOI: https://doi.org/10.13652/j.spjx.1003.5788.2025.60086
cultural distinctiveness in current agricultural food packaging, this study puts forward an innovative approach to promote the upgrade of agricultural food packaging from functional consumption to cultural consumption through intangible cultural heritage (ICH) narrative design. In terms of methodology, the value of ICH narrative in food packaging is first analyzed, followed by the proposal of a design pathway encompassing three aspects: ICH content selection and story construction, narrative graphic and layout design, and material and process selection, with interactive experience being strengthened by integrating technologies such as the Internet of Things (IoT) and augmented reality (AR). In terms of application outcomes, case studies including Shaoxing rice, Luhe souvenirs, Xigui tea, Wuyutai tea, Zhuxianzhen dried tofu, and Jingyang Fu brick tea demonstrate that ICH narrative endows agricultural food products with distinctive cultural features and evokes emotional resonance, while technological means can further broaden the scope of narration. It can be concluded that ICH narrative imparts a non-replicable cultural core to agricultural food packaging, thereby facilitating the transition from functional consumption to cultural consumption. In practice, it is essential to respect community subjectivity, balance tradition and innovation, and conduct prudent cultural and ethical assessments of sensitive content.
