Volume 0,Issue 5,2024 Table of Contents

1 Analysis of the Effects of Ethanol Extracts from Cichorium glandulosum on the Intestinal Flora of db/db Mice Based on High-throughput Sequencing

KANG Jinsen , YAN Junlin , ZHANG Rui , ZHONG Yewei , TAN Huiwen , ADALAITI Abdurixit , TONG Fenglian , MA Xiaoli

2024, 40(5):1-7. DOI: 10.13982/j.mfst.1673-9078.2024.5.0424

[Abstract](345) [HTML](9) [PDF 6.42 M](2469)

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The effects of ethanol extracts obtained from Cichorium glandulosum on the intestinal microbiota of diabetic mice (db/db mice) were investigated. In this study, m/m mice served as the normal control group (CON group), while db/db mice were randomly divided into the model group (MOD group), metformin-treated group (MET group), lowdose ethanol extract-treated group (CGL group), and high-dose ethanol extract-treated group (CGH group). After intragastric administration of ethanol extracts from Cichorium glandulosum for eight weeks, the body weight, fasting blood glucose levels, liver total cholesterol (TC) levels, and liver triglyceride (TG) content in mice were analyzed. Additionally, 16S rRNA sequencing analysis was performed on fecal samples of mice to investigate the changes in their intestinal microbiota after the treatment. It was discovered that the high-dose ethanol extract can regulate the body weight and blood glucose levels of db/db mice and significantly reduce the levels of TC and TG in db/db mice (P<0.05). In the meantime, the 16S rRNA sequencing results showed noticeable differences in the intestinal microbiota among the CON, MOD, and CGH groups. The administration of ethanol extracts from Cichorium glandulosum improved the intestinal dysbiosis in db/db mice and upregulated the relative abundance of beneficial bacteria such as Bifidobacterium, Romboutsia, and Prevotella in the intestinal microbiota. This study has shown that the ethanol extract from Cichorium glandulosum can regulate the intestinal microbiota of db/db mice and regulate glucose and lipid metabolism by increasing the relative abundance of beneficial bacteria. This can provide new insights for the development and utilization of Cichorium glandulosum from Xinjiang as a medicinal resource.

2 Protective Effect of Hepatoprotective and Sobering Soft Candy Mixture on Acute Alcoholic Liver Injury in Mice

LI Donghai , LI Lilang , WANG Yu , LI Xue , ZHANG Chaoju , LI Zuhui , YANG Xiaosheng , YANG Juan

2024, 40(5):8-14. DOI: 10.13982/j.mfst.1673-9078.2024.5.0498

[Abstract](188) [HTML](10) [PDF 3.70 M](2368)

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To study the protective effect of the Liver-protective and Sobering Soft Candy Mixture (LSSCM) against acute alcoholic liver injury in mice, a model of acute alcoholic liver injury was established, the liver index was calculated, and the changes in serum triglycerides (TG), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) as well as the superoxide dismutase (SOD), malondialdehyde (MDA), alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) in liver tissues, were measured. morphological changes were examined through pathological sections of liver tissues. The results showed that compared with the model group, the liver index, TG content and MDA content of the high-dose LSSCM group were significantly reduced by 12.33%, 48.35% and 39.10%, respectively; the levels of SOD, ALDH and ADH increased significantly by 18.61%, 44.59% and 124.61%, respectively; the levels of AST and ALT were significantly reduced by 32.26% and 40.71%, respectively. The results of mouse liver histopathological sections showed that the damaged livers of mice in each dose group of LSSCM were improved to different degrees. In summary, LSSCM had a significant ameliorating effect on hepatomegaly, lipid metabolism disorders, and hepatic oxidative stress caused by alcohol-induced acute liver injury in mice, and could effectively prevent and ameliorate acute alcoholic liver injury.

3 Chemical Composition and Antitumor Activity of Ethyl Acetate Extracts from Ganoderma lucidum Compounds

LIN Xiaoliang , LI Jiahui , LONG Jieyi , LIANG Ming , LIN Hongyu , ZHANG Huiting , AN Siyu , LIU Guo , CAO Yong

2024, 40(5):15-23. DOI: 10.13982/j.mfst.1673-9078.2024.5.0468

[Abstract](160) [HTML](15) [PDF 3.45 M](2337)

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The chemical composition and antitumor activity of ethyl acetate extracts from Ganoderma lucidum compounds (GCE) were investigated. GCE was extracted using ethyl acetate from compounds of Ganoderma lucidum, Cuscuta chinensis Lam, Schisandra chinensis, and Codonopsis pilosula (at a mass ratio of 50.3:25.2:15.7:8.8). Ultra-high pressure liquid chromatography coupled with time-of-flight mass spectrometry (UPLC-Q-TOF-MS) was used to analyze its composition. Blank, model, positive control, and GCE-treated groups (low, medium, and high dosages) were established. The tumor inhibition rate, organ index, splenic lymphocyte proliferation capacity, and serum cytokine levels were measured. The results showed that GCE is mainly composed of 11 compounds: L-pyroglutamic acid, DL-leucine adenosine, D-erythronolactone, L-norleucine, pyrogallol, 2-hydroxy-3-methylpyran-4-one, chlorogenic acid, 3-(3,4,5-trimethoxyphenyl) propionic acid, quercetin, and schisandrin. The tumor inhibition rates of H22 tumor-bearing mice in low-, medium-, and highdose GCE-treated groups (at 50, 100 and 200 mg/kg) H22 were 35.14%, 38.25%, and 50.87%, respectively. Comparison of the model and treated groups revealed that low-, medium-, and high-dose GCE significantly promoted the proliferation of splenic lymphocytes (P<0.01). A high dose of GCE could significantly promote the secretion of IL-6, TNF-α, and IL-12 in mice (P<0.05). In short, GCE has certain inhibitory effects on the tumor of H22 tumor-bearing mice. The results of this study can provide insights into the development of antitumor products.

4 Optimization of Enrichment Culture Medium and Fermentation Conditions for Streptococcus thermophilus 937

PENG Kuiyao , GUAN Chengran , WANG Weijun , HU Yaqian , GU Ruixia

2024, 40(5):24-33. DOI: 10.13982/j.mfst.1673-9078.2024.5.0618

[Abstract](135) [HTML](10) [PDF 7.18 M](2356)

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The optimization process for Streptococcus thermophilus 937 involved starting from a chemically defined medium, followed by single-factor experiments, response surface experiments, and orthogonal optimization experiments to refine the culture medium and growth conditions. The experimentally determined optimal culture medium for Streptococcus thermophilus 937 is 20 g/L lactose, 16.60% enzymatic skim milk, 18.88 g/L soybean oligopeptide, 1.69% whey protein powder, 10 mmol/L histidine, 10 mmol/L isoleucine, 5 mmol/L tyrosine, 1 mmol/L cysteine, 1 mmol/L glutamic acid, 2 mg/L nicotinic acid, 0.5 g/L ascorbic acid, 40 mg/L magnesium chloride, 2 mg/L calcium pantothenate, 4 mg/L thiamine hydrochloride, and 0.4 g/L calcium chloride. The viable cell density of Streptococcus thermophilus 937 reached 1.75×109 CFU/mL when the initial pH was 6.5, with a 2% inoculum and a fermentation temperature of 39 ℃. This work achieved low-cost, highefficiency culture methods for Streptococcus thermophilus 937, and these findings lay a foundation for the development and production of commercial products via Streptococcus thermophilus cultures with high viable cell counts.

5 Virtual Screening and Activity Evaluation of Dipeptidyl Peptidase-IV Inhibitory Peptides from Ginger Protease Hydrolysates

LIU Fendi , LI Jingming , CHEN Hongjiao , LI Xueyan , LIU Yang , LIU Wei

2024, 40(5):34-42. DOI: 10.13982/j.mfst.1673-9078.2024.5.0658

[Abstract](94) [HTML](9) [PDF 3.72 M](2348)

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Based on the hydrolysis specificity of ginger protease, highly bioactive peptide segments were virtually screened from the hydrolysates, followed by validation of in vitro activity and investigation of in vivo absorption into blood. First, highly active peptide segments were virtually screened through Peptide Ranker and molecular docking. Next, an in vitro enzyme-catalyzed reaction system was established to determine the inhibitory activity (IC50) of active peptides against dipeptidyl peptidase-IV (DPP-IV). Based on this, surface plasmon resonance (SPR) was introduced to investigate the interactions between DPP-IV and active peptides. Finally, oral administration experiments in rats were conducted to study the stability of active peptides in the gastrointestinal tract. Through computer simulation, the DPP-IV inhibitory peptide Gly-Pro-Ser-Gly-Pro-Hyp-Gly-Pro-Hyp-Gly-Pro-Hyp-Gly (GPSGPXGPXGPXG) was obtained via virtual screening. Moreover, the in vitro enzyme-catalyzed experiments showed that GPSGPXGPXGPXG has strong inhibitory effects against DPP-IV, with an IC50 of 457.3 μmol/L. SPR experiments further revealed fast binding and dissociation kinetics between the two peptides. However, in vivo experiments in rats suggested that GPSGPXGPXGPXG is not stable in the gastrointestinal tract and it is not absorbed intact, but it is partially absorbed into the circulatory system in the form of dipeptides and tripeptides, including oligopeptides like Pro-Hyp, Gly-Pro-Hyp, and Pro-Hyp-Gly. This study demonstrates that the bioactive peptides obtained via screening cannot maintain their structural integrity after oral absorption through the digestive tract and are hydrolyzed by peptidases in the body. The findings provide theoretical support for subsequent pharmacokinetic and pharmacodynamics studies in vivo.

6 Comparison of the Functional Characteristics of Bovine Bone Marrow Protein and Its Hydrolysate Obtained with Alkaline Protease

ROZI Parhat , ABABAIKERI Gulimire , LIU Yuan , LI Pengfei , CAO Bo , WUMAIER Maimaiti , YANG Xiaojun

2024, 40(5):43-52. DOI: 10.13982/j.mfst.1673-9078.2024.5.0614

[Abstract](111) [HTML](10) [PDF 3.06 M](2352)

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In this study, bovine bone marrow protein (BBMP) was extracted by the water extraction method, and alkaline protease was used to prepare BBMP hydrolysate (Bovine bone marrow protein alkaline protease hydrolysate, BBMP-AH). The amino acid contents of both BBMP and BBMP-AH were determined, and the structural characteristics, physicochemical properties, and antioxidant activities were compared and analyzed. The results showed that the protein content of BBMP-AH was higher than that of BBMP, and BBMP-AH contained higher contents of essential amino acids and hydrophobic amino acids. The UV and FT-IR spectra showed that both BBMP and BBMP-AH exhibited typical protein absorption peaks, and the protein’s secondary structure underwent significant changes after enzymatic hydrolysis. The examinations of physicochemical properties revealed that the isoelectric points of BBMP and BBMP-AH were around pH 6. When the pH was far from the isoelectric point, BBMP and BBMP-AH exhibited better physicochemical properties, whilst the physicochemical properties were significantly improved under acidic and alkaline conditions. Compared with the original protein, the highest solubility of the enzymatic hydrolysate increased to 94.40%, the emulsifying ability was 1.24 m2/g, the emulsion stability was 116.33%, and the water-holding capacity was 3.94 g/g, with a slight decrease in oil-holding capacity. The antioxidant activity of BBMP-AH was significantly stronger than that of BBMP, with both BBMP-AH and BBMP having relatively strong DPPH•, •OH, O2-•, and ABTS+• scavenging abilities and total reducing capacity. In summary, the enzymatic hydrolysis treatment could significantly improve the physicochemical properties of bovine bone marrow protein, increase its antioxidant capacity, and expand the development and application scope of bovine bone marrow protein.

7 Effects of Sterilization Treatments on the Compositions and Functions of Microflora on Duck Eggshell Inner and Outer Surfaces

SUN Jing , PENG Xu , YANG Xue , YANG Hua , LU Lizhi , HU Tianping , XIANG Jun , ZENG Tao , PI Jinsong , DU Jinping

2024, 40(5):53-63. DOI: 10.13982/j.mfst.1673-9078.2024.5.0606

[Abstract](98) [HTML](13) [PDF 7.42 M](2368)

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The effects of sterilization treatments on the microbial compositions on both the inner and outer surfaces of duck eggshells and the ratio of black to yellow salted egg yolks were investigated in this study. Duck eggs were fumigated and cleaned with different fumigants and cleaning agents, and then stored at different temperatures. Changes in the total number of bacteria on duck eggshell inner and outer surfaces before and after treatments were subsequently compared. The effects of sterilization on the microflora on duck eggshell outer surfaces were evaluated using 16S rRNA gene sequencing and PICRUSt gene function prediction. Salted duck eggs were prepared using the mud-packing method at 35 ℃, and the ratio of black to yellow salted egg yolks was calculated. The results show that fumigation significantly inhibits the migration of bacterial colonies from the outer to inner surfaces of the eggshells, effectively controlling the total number of bacteria inside the shell. Two fumigation treatments increase efficacy relative to one. Total bacteria on the outer surface can be reduced to below the detection limit by cleaning. Low-temperature storage can limit bacterial proliferation on both inner and outer eggshell surfaces over 7 days. Total bacteria numbers on both inner and outer surfaces can be significantly reduced by combining fumigation, cleaning, and low-temperature storage. These processes also inhibit bacterial migration, tightly controlling the total bacteria inside the eggshell. 16S rRNA gene sequencing demonstrates a notable reduction in the proportion of Proteobacteria and Psychrobacter on the outer surface of the shell following sterilization treatments. Additionally, PICRUSt gene function prediction indicates a significant decrease in microbial activity within pathways associated with lipid oxidation, amino acid transport, and metabolism after sterilization treatments. Sterilization also significantly reduces the ratio of black to yellow salted egg yolks. These studies illustrate that sterilization treatment effectively decreases total bacteria count on the outer surfaces of duck eggshells and inhibits the occurrence of black salted egg yolks. These findings demonstrate the importance and necessity of sterilization before duck egg processing.

8 Analysis of Differential Substances in Pure and Mixed Culture Fermentation of Jujube Juice by Lactic Acid Bacteria and Yeast in Jujube Juice

ZHANG Jiangning , YE Zheng , YANG Chun

2024, 40(5):64-72. DOI: 10.13982/j.mfst.1673-9078.2024.5.1593

[Abstract](88) [HTML](13) [PDF 8.50 M](2313)

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Here, the effects of pure and mixed culture fermentation by lactic acid bacteria and yeast on the total sugar, total acid, total phenol, flavonoid, and alcohol contents of jujube juice were examined. The analysis of the difference in free phenolic acids was performed with the help of Liquid Chromatography-Mass Spectrometry (LC-MS). The differences in volatile organic compounds were analyzed using Gas Chromatography-Ion Mobility Spectrometry (GC-IMS). The results showed that, regardless of pure and mixed culture fermentation, the total sugar and flavonoid contents decrease, while the total acid, total phenol, and alcohol contents increase. Furthermore, the contents of trans-ferulic acid, 4-hydroxybenzoic acid, hydrocinnamic acid, vanillic acid, benzoic acid, and syringic acid increase. Contrarily, yeast fermentation results in higher contents of total phenols, flavonoids, alcohol, phenylalanine, catechin, epicatechin, syringic acid, and sinapic acid in jujube juice but a low total acid content compared to lactic acid bacteria fermentation. The carbohydrate degradation efficiency, acid production efficiency, total phenol production rate, flavonoid retention rate, and alcohol production efficiency were higher after mixed culture fermentation. Similarly, mixed culture fermentation produces higher contents of free phenolic acids, including trans-ferulic acid, trans-cinnamic acid, vanillic acid, gallic acid, p-coumaric acid, benzoic acid, protocatechuic acid, caffeic acid, and syringic acid than does pure culture fermentation. A total of 53 volatile components were identified, including 11 alcohols, 9 esters, 8 ketones, 8 aldehydes, 2 acids, and 2 pyrazines. In mixed culture fermentation samples, flavor esters, alcohols, and aldehydes account for 17.2%, 58.2%, and 1.3%, respectively. The contents of esters and aldehydes in mixed culture fermentation samples are significantly higher than those in pure culture fermentation samples and original jujube juice samples, resulting in a strong flavor. Therefore, mixed culture fermentation using yeast and lactic acid bacteria can effectively enhance the quality and enrich the taste of fermented jujube juice. This study provides a theoretical, scientific, and practical basis for promoting the application of mixed culture fermentation in the jujube fermentation and production industry.

9 Identification of a Protease Producing Brevibacillus borstelensis Strain and Optimization of Enzyme Production Conditions

LIANG Anjian , SHI Qinlan , WANG Jinli , ZHU Chenglin , ZOU Likou , ZHU Pengcheng , LI Dongliang , TANG Junni

2024, 40(5):73-83. DOI: 10.13982/j.mfst.1673-9078.2024.5.0648

[Abstract](87) [HTML](12) [PDF 4.19 M](2310)

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In order to improve the enzyme production efficiency of an environmentally isolated strain, and provide a preliminary experimental basis for the subsequent application of the strain and its protease, the protease production ability of strain S8 was preliminarily detected using the hydrolysis circle method, and its identity as Brevibacillu sborstelensis was confirmed by comparing the 16S rRNA sequences. The optimal culture conditions and medium components were determined through single-factor experiments. Finally, the culture conditions and medium were further optimized using response surface methodology with the help of Plackett-Burman design and the steepest ascent method. The optimization results showed that the optimal conditions are as follows: a fermentation time of 38.70 h, an inoculum size of 1.84% (V/V), a fermentation temperature at 35 ℃, a yeast powder addition of 23.70 g/L, a pancreatic digest of casein addition of 11.70 g/L, and a MgSO4 addition of 20.20 g/L. The resulting enzyme production activity of the strain reached 114.79 U/mL, which was 209.70% higher than that under non-optimized conditions. The results of this study provide scientific data for the subsequent fermentation application of this strain.

10 Enzymatic Properties of Recombinant Acid Protease Obtained from Trichoderma harzianum and Its Hydrolytic Performance for Soybean Protein Isolate

CHEN Yuchen , YANG Li , GU Min , CHEN Kaixin , HU Qiuyi , QIU Xiaoxian , PENG Jingyi , KE Ye

2024, 40(5):84-91. DOI: 10.13982/j.mfst.1673-9078.2024.5.1292

[Abstract](72) [HTML](13) [PDF 3.19 M](2308)

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In order to study the properties of acid protease (Ap) from Trichoderma harzianum, the acid protease gene was cloned using RT-PCR and then transferred to the Pichia pastoris GS115 strain to obtain high expression. Subsequently, the enzymatic properties of this recombinant acid protease (rAp) and its performance in hydrolyzing soybean protein isolate were determined. It was observed that the activity of rAp in the fermentation broth reached 21.5 U/mL when the recombinant P. pastoris was induced in a 500 mL triangular flask. This rAp is an aspartic protease with an optimal temperature of 55 ℃ and an optimum pH value of 2.5, which exhibited strong thermal stability after treatment at 40 ℃ for 120 min. After 24 h treatments in buffers of different pH, rAp still demonstrated excellent stability in the pH range of 2.00~5.00. The relative activity of rAp significantly increased to 116.21%, 113.79%, and 117.44% by Cu2+, Ni2+, and Mn2+, respectively. In the meantime, rAp activity was significantly inhibited by Fe2+, Fe3+, 0.50% SDS, and 5.00% Triton X-100, and the resulting relative enzyme activity was 78.02%, 79.26%, 2.6%, and 13.19%, respectively. After hydrolysis of soybean protein isolates by rAp and pepsin, the relative protein contents of the hydrolyzed products were 14.67% and 3.64%, respectively. Moreover, the β-conglycinin antigenicity is reduced by 30.01% and 26.11%, respectively, and the antigenicity of globulin is decreased by 22.37% and 15.63%, respectively. Based on these results, it is clear that rAp has a strong ability to hydrolyze and reduce the antigenicity of soybean isolates, demonstrating its potential development and application value.

11 Optimization of Enzymatic Hydrolysis of Nacre Peptide and Its Effects on Energy Metabolism of Human Hepatoma Cells (HepG2)

LI Dongbing , LAN Meng , WANG Yuelong , LIU Lu , SHEN Jiaming , LI Jingfeng , ZHANG Hui , SUN Jiaming

2024, 40(5):92-101. DOI: 10.13982/j.mfst.1673-9078.2024.5.0607

[Abstract](88) [HTML](13) [PDF 9.20 M](2311)

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With the aim of enhancing the enzymatic hydrolysis of nacre peptide, we optimized enzymatic hydrolysis conditions, including the amount of biomimetic enzymes added and the extraction time and temperature, employing a Box-Behnken response design based on the degree of hydrolysis. The inhibitory effects of different mass concentrations of nacre peptide on HepG2 hepatoma cells were also investigated. The established optimal enzymatic hydrolysis conditions were as follows: a temperature of 55 ℃, pH adjusted to 2.0, and the addition of 1% (m/m) pepsin. Following enzymatic hydrolysis for 2.6 h, the pH was adjusted to 8.0 and 1.7% (m/m) trypsin was added for further enzymatic hydrolysis for 3 h. Under these conditions, percentage nacre peptide hydrolysis values of up to 31.21% were achieved. The nacre peptides obtained under the aforementioned conditions were assessed for their inhibitory effects on hepatoma cells. Experimental results revealed that nacre peptides, at different mass concentrations (12.5, 25, 50, 100, and 200 μg/mL), could reduce the rate of cell survival compared with the cobalt chloride (CoCl2)-induced hypoxia model of HepG2. Furthermore, results of an analysis of nacre peptide amino acids revealed that arginine might be involved in inhibiting the proliferation of hepatoma cells. From the perspective of energy metabolism, nacre peptides inhibited the proliferation of HepG2 cells by reducing the production of adenosine triphosphate and lactate, as well as by suppressing the activities of key energy metabolism-related enzymes, namely, hexokinase, pyruvate kinase, and lactate dehydrogenase. These findings can serve as a reference for the preparation of nacre peptides and provide a theoretical basis for their further development and utilization.

12 Chemical Composition Difference and in Vitro Activity of Different Varieties of Oolong Tea before and After Roasting

HOU Can , LIN Quan , HAO Binxiu , QI Jingjie , CHEN Zhixiong , ZHENG Bin , LI Song , YING Jian

2024, 40(5):102-110. DOI: 10.13982/j.mfst.1673-9078.2024.5.0581

[Abstract](126) [HTML](14) [PDF 2.47 M](2403)

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In order to study the changing trend of mass base and difference in activity of different raw oolong tea materials after roasting, the differences in the contents of total polyphenols, total flavonoids, tea polysaccharides, catechins and caffeine of different raw oolong tea materials before and after roasting were analyzed. In vitro enzymatic biochemical reaction was used to investigate the inhibitory abilities of different oolong tea raw materials and finished products against α-glucosidase, lipase and xanthine oxidase. The results showed that the content of tea polyphenols decreased from 13.75%~15.59% in raw materials to 12.41%~14.14% in the finished products, with the contents of Tieguanyin and Rougui being slightly higher than those of Old Fir Narcissus, Sanyin Narcissus and Dahongpao (P<0.05). The content (mass fraction) of total flavonoids in the raw materials ranged from 0.71% to 1.00%, and the content of total flavonoids in Tieguanyin raw materials was the lowest, which was significantly different from those of other raw materials (P<0.05). Except for Tieguanyin, the contents of total flavonoids in other oolong tea samples were insignificantly different before and after roasting (P>0.05). The contents of tea polysaccharides in the raw materials were 1.14%~1.82%, which increased to 1.64%~2.12% in the finished products after baking. All the samples showed the inhibitory abilities against α-glucosidase, lipase and xanthine oxidase, and the finished products after baking exhibited weaker inhibitory abilities against α-glucosidase and lipase. Rougui showed higher abilities to inhibit α-glucosidase and lipase activities. After roasting, oolong tea had an enhanced ability to inhibit xanthine oxidase, with the IC50 values decreasing from 13.21~17.42 mg/mL to 10.26 mg/mL~14.38 mg/mL for the finished product

13 Release Characteristics of Rice Starch-polyphenol Complex under Different Conditions

XU Min , HAN Xueqin , CHEN Tiange , Sher Ali Khan , LI Yongxian , XU Jucai , MAO Yinguang , GAN Yuze , HUANG Lixin , LIU Lei

2024, 40(5):111-118. DOI: 10.13982/j.mfst.1673-9078.2024.5.0546

[Abstract](99) [HTML](10) [PDF 2.13 M](2328)

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After studying the formation of complexes between the main monomers of phenols (ferulic acid, gallic acid) in rice and rice starch, the effects of polyphenols on the acitivity of α-amylase and glucosidase were investigated, as well as the release characteristics of polyphenols in the complex under different conditions. The results showed that under the action of α-amylase, the hydrolysis rate of starch decreased with an increase of polyphenol content in the complex from 5% to 20% (ferulic acid group decreased from 54% to 49.69%, gallic acid group decreased from 57.97% to 49.81%). Similarly, under the action of glucosidase, the hydrolysis rate of gallic acid decreased significantly from 65.72% to 57.13%. Regarding digestion characteristics, the addition of gallic acid involving different addition amounts (from 5% to 20%) significantly reduced the content of RDS from 80.76% to 64.62%, the SDS content of ferulic acid decreased (from 15.69% to 14.07%), and the RS content increased significantly from 11.26% to 16.69%. The release of ferulic acid by the complex increased by 131.43% with an increase in temperature of the aqueous solution (30~80 ℃). With increased pH values (2~6), the release of ferulic acid exhibited a trend of first decreasing and then increasing, while the release of gallic acid displayed an increasing trend. In simulated gastrointestinal digestion experiments, it was found that ferulic acid was released in advance in gastric juice, while the release of gallic acid (5%) in intestinal juice decreased from 2.19 mg to 1.56 mg. These results provide a theoretical reference for the application of dietary polyphenols in starch-based functional foods.

14 Effect of Different Wavelengths of LED Light Irradiation on the Physicochemical Quality of Blueberries during Postharvest Cold Storage

LI Yang , YUAN Di , CHEN Feng

2024, 40(5):119-126. DOI: 10.13982/j.mfst.1673-9078.2024.5.0552

[Abstract](96) [HTML](13) [PDF 2.38 M](2354)

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In order to study the effect of light treatment on the physicochemical quality of postharvest blueberries during cold storage, in this experiment, dark treatment was used as the control group, and blueberries were treated with LED red light (620 nm), blue light (460 nm), and white light (450 nm) under full light conditions at 4 ℃ for 12 d. Samples were taken every 2 d to analyze the effects of different LED light irradiation treatments on the appearance quality and nutrient indexes of blueberries during storage. The results showed that compared with the dark control group, all light treatments were beneficial for maintaining the original color of the fruit, and after 12 days of storage, the blueberries in the blue light treatment group had the highest hardness, with the soluble solids mass fraction and titratable acid content being 13.15% and 1.27%, respectively. The anthocyanin content reached 45.79 mg/g, which was 3.48 times that of the control group; Among the light treatment groups, LED blue light could significantly inhibit the increase of malondialdehyde (content was only 0.88 μmol/g). Moreover, the blue and red light radiation could significantly inhibit the increases of PPO and POD activities and reduce the degree of browning of blueberry fruits, with the effect of blue light being more significant (P<0.05). Therefore, the blue light treatment was more conducive to maintaining the postharvest storage quality and nutritional value of blueberries and prolonging the shelf life, while providing a theoretical basis for postharvest blueberry preservation technology, which has certain application potential.

15 Bactericidal Effect of Ultra-high Pressure on the Spoilage Mold of Wet Starch Vermicelli and Its Induced Quality Changes

BI Xiufang , CHEN Yan , JIAO Wencheng , WANG Xiaoqiong

2024, 40(5):127-133. DOI: 10.13982/j.mfst.1673-9078.2024.5.0551

[Abstract](78) [HTML](16) [PDF 2.41 M](2308)

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The effects of different UHP conditions on the inactivation of the spoilage molds, Aspergillus niger (Aspergillus 305.01 and Aspergillus 305.02), in wet starch vermicelli and the cooking characteristics of wet starch vermicelli were studied. The experimental results showed that the inactivation effect of UHP on Aspergillus niger increased as the treatment pressure and time increased. After the UHP treatment at 400 MPa/10 min, both the Aspergillus 305.01 and Aspergillus 305.02 of the vermicelli decreased by 6.01 log10 CFU/mL. Compared with the untreated bacterial suspensions, the nucleic acid absorbance values corresponding to Aspergillus 305.01 and Aspergillus 305.02 increased from 0.03 and 0.04 to 0.56 and 0.48, respectively, the protein absorbance values increased from 0.04 and 0.08 to 0.70 and 0.44, respectively, and the conductivity increased from 0.04 mS/cm and 0.06 mS/cm to 0.12 mS/cm and 0.20 mS/cm, respectively. Under the 400 MPa treatment, increasing the UHP treatment time led to increases of conductivity, nucleic acid loss and protein loss. The results showed that UHP could induce the outflow of intracellular substances such as nucleic acids, proteins and electrolytes, thereby causing cells death, through altering partial function of the cell membrane. In addition, as the processing time prolonged, the boiling loss and swelling degree of the vermicelli increased, whilst the breakage rate changed insignificantly. Based on the effect of UHP on the sterilization effect and cooking characteristics of wet starch vermicelli, the treatment at 400 MPa for 10 min was a better approach for sterilizing wet starch vermicelli, which provides a theoretical basis for UHP to improve the sterilization effect and quality of wet starch vermicelli.

16 Effect of Slightly Acidic Hypochlorous Acid Water on the Preservation of Fresh-cut Lettuce

CHEN Qianru , YU Yifan , ZHAO Namula , ZHANG Jingjing , YUN Xueyan , DONG Tungalag

2024, 40(5):134-141. DOI: 10.13982/j.mfst.1673-9078.2024.5.0343

[Abstract](77) [HTML](11) [PDF 2.13 M](2324)

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Fresh-cut fruits and vegetables have a short shelf life and are prone to contamination by foodborne pathogens. In this study, fresh-cut lettuce was used as the test material, and based on single factor and orthogonal experiments, the preservation effect of slightly acidic hypochlorous water (SAHW) on fresh-cut lettuce and its influence on storage quality were studied. Using four factors SAHW available chlorine concentration, treatment temperature, treatment time and treatment method, on the basis of single factor experiments, a four-factor three-level orthogonal test was conducted to verify the effect of the best treatment on the sensory quality, total bacterial count, ascorbic acid (Vc) content and Malondialdehyde (MDA) content of fresh-cut lettuce during storage. The results showed that SAHW had a good preservation effect on fresh-cut lettuce, and the influencing factors were the treatment method>treatment time>effective chlorine concentration of SAHW>treatment temperature. The best preservation treatment was shaking and soaking in the SAHW with an effective chlorine concentration of 50 mg/L for 5 min at 15 ℃. Under this treatment, the sensory score was 5.22, the a* value was -2.73, and the total bacterial count was 3.79 lg CFU/mL. This treatment maintained effectively the sensory quality of fresh-cut lettuce during storage. On the 25th day of storage, the total bacterial count was only 0.72 lg CFU/mL (indicating the inhibition of the growth of bacterial colonies), Vc was 14.5 mg/100 g, and the MDA was 0.26 nmol/g, indicating the reduction of Vc loss and MDA accumulation significantly and extension of the shelf life of fresh-cut lettuce. The results provide a scientific basis for SAHW to be used as a preservative agent for fresh-cut lettuce.

17 Preparation, Characterization and Application of Compound CuO/CaMoO4 Antibacterial Agent in Cucumber Storage

ZHANG Huimin

2024, 40(5):142-149. DOI: 10.13982/j.mfst.1673-9078.2024.5.0399

[Abstract](85) [HTML](9) [PDF 4.12 M](2456)

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In this paper, ammonium molybdate, eggshell and cetyltrimethyl ammonium bromide were used as raw materials to prepare CaMoO4 with improved performance by adjusting the calcination temperature. Additionally, a CuO/CaMoO4 composite antibacterial agent was synthesized using calcium molybdate, copper sulfate, and sodium borohydride as raw materials. The effects of CuO/CaMoO4 antibacterial dosage, culture time, and copper content on antibacterial activity and the antibacterial effect of CuO/CaMoO4 on Escherichia coli (E. coli) were studied under light and dark reaction conditions. The CuO/CaMoO4 composite antibacterial agent synthesized at 650 ℃ exhibited the best antibacterial efficacy. Moreover, when the copper content was 1.20%, the antibacterial rate could reach 100% under light and dark conditions. Bacteriostatic testing of plastic wrapping material containing CuO/CaMoO4 compound antibacterial agent showed that the agent could effectively inhibit E. coli on food surfaces, and the antibacterial rate remained at 100% even after four days of storage. Furthermore, the CuO/CaMoO4 antibacterial compound displayed excellent biocompatibility. Overall, the compound CuO/CaMoO4 antibacterial agent demonstrated rapid and efficient inhibition of E. coli, thereby ensuring food safety and offering novel insights for food storage practices.

18 Effects of Amino Acid Types and Added Amounts on Quality Characteristics of Emulsified Chicken Products

WANG Xinying , MAO Yun , NIU Xiyue , REN Xiaopu , WANG Linlin , MA Long , ZHANG Shengxiu , WANG Yilang

2024, 40(5):150-161. DOI: 10.13982/j.mfst.1673-9078.2024.5.0456

[Abstract](85) [HTML](14) [PDF 7.19 M](2317)

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To investigate the effects of amino acid types and their addition amounts on the quality characteristics of emulsified chicken minced products, and to obtain the amino acid types and addition amounts that best improve the quality of emulsified chicken minced products. In this paper, emulsified minced chicken meat with varying ratios of L-lysine (Lys), L-arginine (Arg), L-histidine (His) and L-cysteine (Cys) was used to determine and analyze eating quality, emulsification characteristics, textural characteristics, rheology, flavor substances, sensory quality, and microstructure. The results showed that the addition of Lys, Arg, and His significantly decreased the TEF, EFTA, and CL values of emulsified ground meat, but significantly increased the pH, hardness, viscosity, and chewiness of the emulsified product more effectively than the addition of Cys. Rheological analysis revealed that Lys, Arg, and His increased the final storage modulus. Additionally, scanning electron microscopy showed that Lys, Arg, and His contributed to the formation of a tight gel mesh structure. Overall, 0.50% Lys, 0.60% Arg, and 0.90% His were the optimal addition quantities. These findings suggest that Lys, Arg, and His have potential in the preparation of emulsified meat products.

19 Extraction of Polyphenols from Oil Peony Seed Coats and Their Antioxidant and in Vitro Fermentation Characteristics

SUN Zhaoyue , CUI Wenyu , CHENG Anwei

2024, 40(5):162-170. DOI: 10.13982/j.mfst.1673-9078.2024.5.0616

[Abstract](78) [HTML](13) [PDF 3.67 M](2354)

Abstract:
Ultrasonic-assisted extraction of polyphenols from oil peony seed coats (OPSCP) was conducted, and the extraction yield was used as an evaluation index to optimize extraction conditions through single-factor experiments and response surface analysis. In addition, the antioxidant activity and in vitro fermentation characteristics of OPSCP were determined. The results showed that the optimal conditions of ultrasonic-assisted extraction of OPSCP are as follows: ethanol 60% V/V, solid-liquid ratio of 1:40, ultrasonic power of 480 W, and extraction time of 50 min. The polyphenol extraction yield equaled 83.11 mg GAE/g under the optimal conditions. The IC50 of DPPH, ABTS+ radical scavenging rate, and FRAP values of OPSCP in DPPH, ABTS, and FRAP assays were 8.19 mg GAE/g, 5.83 mg GAE/g, and 16.46 mg GAE/g, respectively, indicating good antioxidant activity. In vitro fermentation experiments showed that OPSCP can reduce the pH of the fermentation broth and increase the content of short-chain fatty acids (SCFAs) for both the normal and obese groups, with a more pronounced effect observed in the obese group. This study indicates that the polyphenols from oil peony seed coats exhibit significant in vitro antioxidant activity and have the effect potential to lower the pH and increase SCFAs in intestinal fermentation broth in vitro.

20 Effects of Colloid Milling and Freeze Milling on the Quality of Mango Pulp

WANG Xun , GU Yumei , MI Shengxi , ZHAO Qiangzhong

2024, 40(5):171-180. DOI: 10.13982/j.mfst.1673-9078.2024.5.0588

[Abstract](88) [HTML](10) [PDF 4.63 M](2297)

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In this paper, the effects of colloid milling and freeze milling on the quality of mango pulp were compared. The study showed that there were no significance differences in moisture, ash, protein, total acid, total sugar, and fiber contents of mango pulp by the two milling methods (P>0.05). The total phenolic content and ABTS scavenging ability of mango pulp prepared by colloid milling were 27.42 mg GAE/100 g and 9.04 μmol TE/g respectively, while those of mango pulp prepared by freezing milling were 31.18 mg GAE/100 g and 9.75 μmol TE/g, respectively. These results indicate that freezing milling could better protect the antioxidant activity of mango pulp. The average particle size of mango pulp prepared by colloid milling was 110.34 μm, whereas that of pulp prepared by freeze milling was only 59.49 μm; thus the texture and dispersion properties of mango pulp prepared by freeze milling were improved. The L*, a* and b* values of mango pulp prepared by freeze milling were significantly higher than those of pulp prepared by colloid milling (P<0.05). The total terpene compounds of mango pulp prepared by freeze milling was 1 805.56 μg/L, significantly higher than the 416.96 μg/L of pulp prepared by colloid milling. The sensory evaluation scores of mango flavor, grass flavor, and texture were higher, and mango pulp prepared by freeze milling had superior color, flavor, and eating quality. In summary, mango pulp prepared by freeze milling was better in terms of antioxidant activity, microstructure, and sensory qualities. Freeze milling can effectively preserve mango pulp quality and can be used as a new type of mango pulp processing technology.

21 Gelatinization and Gelling Properties of Blends of Wheat Starch and Potato Starch or Pea Starch

LI Shuyue , LIN Jiangtao , YUE Qinghua , ZHENG Yan , LI Xinling , ZENG Jia

2024, 40(5):181-188. DOI: 10.13982/j.mfst.1673-9078.2024.5.0649

[Abstract](80) [HTML](12) [PDF 2.84 M](150)

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The gelatinization, rheological and gel properties of the starch mixtures obtained through mixing wheat starch with potato starch or pea starch in different proportions were studied. The results show that the gelatinization characteristic parameters such as the peak viscosity of wheat starch (2 430.50 Pa•s) were lower than those of potato starch (9 001.02 Pa•s) and pea starch (2 644.50 Pa•s), whereas, the gelatinization temperature of wheat starch (90.70 ℃) was higher than those of potato starch (67.05 ℃) and pea starch (73.95 ℃). The gelatinization characteristic values of the two mixed starch systems varied between the values of the wheat starch and potato starch, and those of the wheat starch and pea starch. Parameters such as the texture of the gel and the state of water molecules exhibited similar characteristics. The moduli of wheat starch (G′, 4 770.85 Pa; G″, 453.80 Pa) were higher than those of potato starch (G′, 1 392.46 Pa; G″, 175.65 Pa) and pea starch (G′, 3 256.89 Pa; G″, 275.36 Pa). The storage modulus and loss modulus of the two mixed starch systems varied between the values of wheat starch- potato starch and wheat starch-pea starch. The enthalpy values of potato starch (7.84 J/g) and pea starch (8.18 J/g) were lower than that of wheat starch (13.06 J/g), with the enthalpy values of wheat starch-potato starch and wheat starch-pea starch being reduced. In summary, mixing wheat starch with potato starch or pea starch could change the properties of the mixed starch to different extents, which can provide a certain theoretical basis for the natural modification of starch.

22 Enzymatic Preparation and Characterization of Microcrystalline Cellulose from Perilla Seed Meal

GUO Yurong , LI Huizhen , ZHANG Zhijun , HAN Wanyu , WANG Yanbo

2024, 40(5):189-198. DOI: 10.13982/j.mfst.1673-9078.2024.5.0733

[Abstract](77) [HTML](7) [PDF 6.83 M](143)

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The enzymatic preparation of Perilla seed meal microcrystalline cellulose (PSM-MCC) was optimized, and its structure and properties were characterized. Response surface methodology was used to determine the optimal conditions for enzymatic preparation of PSM-MCC from Perilla seed meal cellulose (PSM-CL). The physicochemical and functional characteristics of PSM-MCC were studied. PSM-MCC was characterized using Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy. The optimum conditions for preparing PSM-MCC using cellulase are as follows: pH at 5.0, PSM-CL to water ratio of 1:20 g/mL, enzyme addition of 0.4% (m/m), hydrolysis temperature at 55 ℃, and reaction time of 3 h. Under these conditions, the yield of PSM-MCC equals 90.74%, and the degree of polymerization reaches 134. Impurities such as lignin in PSM-MCC are removed, with an increase in crystallinity from 49.39% to 61.37%. Compared with PSM-CL, PSM-MCC prepared through hydrolysis by cellulase exhibits better thermal stability, with a smaller diameter of 48.26 μm. In addition, its surface is porous and shows a layered structure. PSM-MCC prepared through enzymatic hydrolysis has excellent properties and meets national standards, and it is expected to be used in many fields, such as food, pharmaceuticals, and composite materials.

23 Quality Changes of Organized Walnut Protein under Extrusion Treatment

ZHANG Jianing , WANG Chenyan , HAO Yanbin , ZHANG Yunqi , TIAN Yiling , DING Baomiao , QI Jianxun , CHEN Yonghao

2024, 40(5):199-211. DOI: 10.13982/j.mfst.1673-9078.2024.5.0436

[Abstract](73) [HTML](11) [PDF 5.51 M](136)

Abstract:
作为核桃制油副产物的核桃蛋白是一种优质植物蛋白，核桃蛋白高值化利用，对核桃产业可持续发展具有重要意义。该研究采用挤压法对核桃蛋白进行组织化，考察挤压工艺参数对组织化核桃蛋白色泽、质构特性和组织化度的影响。通过采用单因素法，研究了挤压温度、水分含量、螺杆转速、喂料速度和冷却温度5个挤压工艺参数对组织化核桃蛋白的影响。根据单因素试验结果，选择挤压温度、水分含量和喂料速度三个参数为响应面实验的试验因素，以组织化度为响应值，应用响应面分析法对挤压工艺参数进行优化，得到了最优挤压工艺参数为挤压温度141 ℃，水分含量52.7%，螺杆转速160 r/min，喂料速度26 g/min，冷却温度65 ℃，此时组织化度为1.209。该研究为核桃蛋白基素肉开发奠定了基础。

24 Comparison of Antioxidant and Flavor Quality of Bayberry Soup Produced by Two Different Processing Methods

LI Guolin , LI Dandan , WANG Chengyou , HE Yangbo , LI Yongfu , CHEN Limei

2024, 40(5):212-220. DOI: 10.13982/j.mfst.1673-9078.2024.5.0539

[Abstract](87) [HTML](10) [PDF 3.56 M](156)

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Bayberry soup is a unique processed product from Guizhou province. The quality of bayberry soup produced by two different processing methods was investigated. The contents of vitamin C, total phenols, flavonoids, anthocyanins, and the antioxidant properties of bayberry soup were determined using the 2,2-biphenyl-1-picrylhydrazine (DPPH) and 2,2’-diazobis (3-ethylbenzothiazolin-6-sulfonic acid) diamine salt (ABTS) methods. Additionally, the flavor and volatile components were preliminarily explored. The results showed that the contents of vitamin C (Vc), anthocyanins, total phenols, and flavonoids in bayberry soup packaged in aluminum cans were higher than those in polypropylene (pp) cans during storage. At the end of storage, Vc and anthocyanin levels were 126.50% and 37.36% higher, respectively, than those in pp cans, with statistically significant differences. The DPPH and ABTS clearance rates of bayberry soup in aluminum can were higher than those of pp cans. The electronic nose flavor showed that the two flavors were basically the same, and the odor characteristics completely overlapped after 120 days of storage. Levels of α- caryophyllene in aluminum cans were 16.09% greater than in pp cans, but the types were slightly less than pp cans. In summary, aluminum can packaging is more conducive to improving the storage quality of bayberry soup. This study provides theoretical parameters are provided for the production and processing of Yangmei soup and offers theoretical guidance for improving quality and extending shelf life.

25 Analysis of Key Aroma Compounds in Essential Oils from the Fruit Peels of Four Citrus Varieties by HS-SPME-GC-MS Combined with Relative Odor Activity Value

LI Li , JIANG Jinglong , HU Jiale , SHI Yixuan , HUANG Pei , DING Dekuan

2024, 40(5):221-230. DOI: 10.13982/j.mfst.1673-9078.2024.5.0139

[Abstract](90) [HTML](16) [PDF 5.18 M](141)

Abstract:
To provide the basis for the quality evaluation of citrus peel essential oils and the discovery of special aroma citrus essential oils, the composition and content of volatile substances in the essential oil from the fruit peels of four citrus varieties were analyzed by headspace-solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GCMS), along with relative odor activity values (ROAVs) of the key aroma components in four kinds of citrus peel essential oils. The results showed that a total of 62 volatile compounds were identified from the essential oils of four citrus cultivars, including 13 monoterpene, 14 sesquiterpene, 5 alkanes, 12 alcohols, 8 esters, 4 aldehydes, 3 ketones, 2 ethers and 1 acid. Among the four citrus peel essential oils, the content of monoterpene (83.00%~91.93%) was the highest. According to the compound composition, the four citrus species can be divided into two chemical types: limonene/γ-terpinene type and limonene//3-carene type. Twenty-four key aroma compounds were screened from four citrus peel essential oils by ROAV, among which perillaldehyde was the most important flavor contributor in the essential oils of Citrus meyerii Y. Tan., and there were 10 key aroma substances. Linalool was the most important flavor contributor in the essential oils of Citrus unshiu Marc., Citrus aurantium L. and Citrus wilsonii Tanaka, and there were 12, 20 and 20 key aroma components, respectively. These key aroma components play important roles in the aroma quality of citrus peel essential oils.

26 Analysis of Differences in Volatile Flavor Substances in Soybean Curd Coated by Raw and Cooked Pulping Techniques

YANG Yumei , TANG Pengyu , HUANG Daomei , MENG Fanbo , LIN Mao

2024, 40(5):231-239. DOI: 10.13982/j.mfst.1673-9078.2024.5.0632

[Abstract](75) [HTML](10) [PDF 3.21 M](178)

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Electronic nose and headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) were used to determine and analyze volatile flavor substances in the preparation of packaged tofu after raw and cooked pulping processes. A total of 59 compounds were detected in two samples, including 15 alcohols, 9 esters, 2 alkanes, 18 aldehydes, 11 ketones, 2 phenols, and 2 other compounds. The results of the relative odor activity value (ROAV) showed that there were 23 key flavor substances (ROAV ≥ 1) in packaged tofu. Notably among these were, N-hexyl aldehyde, heptanal, n-octanal, 2-heptenal, trans-2-octanal, capric aldehyde, (E,E)-2, 4-nonadienal, 2-undecylenal, trans-2, 4-decandienal, n-amyl alcohol, 1-octane-3-ol, 1-heptanol, 1-nonanol, 2-octanone, 2-nonanone and 2-n-amylfuran. These characteristic volatile substances are shared by both kinds of wrapped tofu, contributing significantly to their unique flavor. Trans-2-decenal and 2-heptanone were identified as key flavor substances in cooked pulp samples, while nonanal, 1-nonanol, ethyl n-caproate and 2-phenethyl caproate were key flavor substances in raw pulp samples. Understanding the flavor components of bean curd generated by cooked and raw pulping processes has significant implications for the actual production of bean curd.

27 Identification of Dehydrated Milk Powder Origin Based on Electronic Nose and One-dimensional Laplacian Convolution Kernel

ZHANG Yinsheng , YUAN Hang , ZHOU Ya , CHENG Yongbo , WANG Haiyan

2024, 40(5):240-246. DOI: 10.13982/j.mfst.1673-9078.2024.5.0299

[Abstract](69) [HTML](12) [PDF 5.55 M](134)

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Dehydrated milk powder serves as the fundamental raw material for formula milk, and its place of origin affects the quality of terminal dairy products. In this paper, a method for discriminating the source of dehydrated milk powder by employing electronic nose technology and utilizing a one-dimensional Laplacian convolution kernel is proposed. Sample data is collected using an electronic nose, and after temporal signal alignment, various orders of one-dimensional Laplacian convolution kernels are applied to extract features. Additionally, other feature extraction methods such as statistical numerical features, fast Fourier transform, and discrete cosine transform were compared. Subsequently, partial least squares and visualization were used for separability analysis. Experimental results revealed that the fast Fourier transform, discrete cosine transform, and second-order one-dimensional Laplacian convolution kernels effectively improved separability relative to the original features. The R2 effect size of partial least squares was increased from 0.61 to 0.95, 0.96, and 1.00. The one-dimensional Laplacian convolution kernel feature extraction method was able to accurately distinguish between domestically produced and foreign (Australia) base powder. In a case study, it achieved the best discrimination effect, indicating that it can effectively extract time response features of electronic nose channel sequence signals. This method can facilitate the differentiation work of dehydrated milk powder samples in China and Australia, providing technical support for the rapid identification of dehydrated milk powder sources.

28 Discrimination of Three Chinese Indigenous Chicken Breeds Based on Near- Infrared Hyperspectral Imaging Technology

JIN Hangfeng , YU Changhao , FAN Kaiping , WU Jianqing , YAN Feifei , WANG Han

2024, 40(5):247-254. DOI: 10.13982/j.mfst.1673-9078.2024.5.0491

[Abstract](69) [HTML](18) [PDF 4.98 M](173)

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China has abundant indigenous chicken breeds, and different breeds of indigenous chicken vary significantly in terms of nutrition, taste, and flavor. In this study, near-infrared hyperspectral imaging technology was used to study the discrimination method for indigenous chicken breeds. Longyou Partridge Chicken (LPC), Jiangshan Wugu Chicken (JWC) and Silkies Chicken (SC) were used as the research objects. Hyperspectral images of three chicken breeds in the band range of 900~1 700 nm were collected and spectral data were extracted. After preprocessing the spectral data, characteristic wavelengths were selected and PLS and SVM discrimination models were established. The results showed that the Detrending-SNV pre-treatment method was the optimal preprocessing method, with ACCc, ACCp and ACCt being 94.17%, 95% and 94.59%, respectively (which increased by 1.76%, 5.26% and 3.52%, respectively, compared with the full spectrum model). The research results showed that it is feasible to use near-infrared hyperspectral imaging technology to discriminate indigenous chicken breeds.

29 Index System of Mango Maturity Established by Principal Component Analysis and Least Partial Squares Method

CHENG Jianhu , ZHOU Xinqun , LIU Bangdi , SUN Jing , ZHANG Min , LIU Yu , CUI Kuanbo , ZHU Xuan

2024, 40(5):255-264. DOI: 10.13982/j.mfst.1673-9078.2024.5.0555

[Abstract](77) [HTML](9) [PDF 6.40 M](146)

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To establish a maturity determination index system for “Tainong No.1” mangoes and determine representative maturity determination indices, mangoes harvested at different times and locations were analyzed for changes in physiological postharvest ripening indicators, including flesh and skin color, texture (hardness, adhesion, elasticity, chewiness), soluble solids, and titratable acidity. A systemic study of postharvest ripening physiological indicators was conducted using principal component analysis and partial least squares methods. The results showed differences in physiological postharvest ripening indicators among batches of “Tainong No.1” mangoes harvested at the same initial maturity level. Using the partial least squares and principal component analysis methods, flesh b*, titratable acidity, and hardness were determined to be the first, second, and third final indicators for evaluating fruit ripeness, respectively. The accuracy rates of maturity determination for the three indicators were 94.34%, 87.21%, and 68.09%, respectively. In conclusion, by establishing a comprehensive evaluation index system and determining the corresponding maturity level index values, theoretical guidance and practical value for timely harvesting and sales of “Tainong No.1” mangoes in different regions were provided.

30 Characteristics and Mechanism of Photodegradation of 5-Hydroxymethylfurfural in Water Induced by Ultraviolet Irradiation

DI Miaomiao , TU Qinghui , CHEN Zhongzheng , LIN Xiaorong , LI Bin , ZHANG Yuanyuan

2024, 40(5):265-273. DOI: 10.13982/j.mfst.1673-9078.2024.5.0535

[Abstract](75) [HTML](11) [PDF 4.88 M](244)

Abstract:
To explore the characteristics and mechanism of ultraviolet (UV) irradiation-induced photodegradation of 5-hydroxymethylfurfural (5-HMF), an aqueous simulation system of 5-HMF was constructed, and the effects of UV irradiation time, light intensity, initial mass concentration of 5-HMF and photosensitizers (FeSO4, TiO2 and VB2) on the degradation of 5-HMF were analyzed. The UV photodegradation reactivity of 5-HMF was analyzed by the density functional theory (DFT), and its UV degradation products were identified by an ultra-high performance liquid chromatography quadrupole time-of-flight tandem mass spectrometer. The results showed that the longer the UV irradiation time, the higher light intensity, the smaller the initial mass concentration of 5-HMF, and the higher the degradation rate. The degradation rate was the highest (83.64%) when the UV irradiation intensity was 400 μW/cm2, the radiation time was 240 min and the initial mass concentration was 31.5 mg/L. Both FeSO4 and TiO2 promoted the UV-induced degradation of 5-HMF, whilst VB2 inhibited the degradation of 5-HMF. The degradation rates of 5-HMF were the highest when the added concentrations and mass fractions of FeSO4 and TiO2 were 1.0 mmol/L and 0.025%: 100.00% (irradiation time 40 min, light intensity 400 μW/cm2) and 76.68% (irradiation time 80 min, light intensity 400 μW/cm2), respectively. The results of DFT analysis showed that the C=O bond of 5-HMF was more susceptible to attack and degradation, and the chemical bonds between C4-C11 and C1-C8 were easily broken. One, two and five degradation products of 5-HMF were identified in the UV, UV/FeSO4 and UV/TiO2 systems, respectively. The results of DFT analysis were consistent with the results of mass spectrometry identification. This study provides a theoretical and applied research basis for the reduction of 5-HMF in foods.

31 Determination of Moisture Content of Hazelnuts Based on Hyperspectral Image Feature Fusion

ZHANG Dongyan , MA Miaoyuan , HUANG Ying , MAO Siyu

2024, 40(5):274-281. DOI: 10.13982/j.mfst.1673-9078.2024.5.0585

[Abstract](69) [HTML](14) [PDF 6.43 M](153)

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For the rapid, non-destructive detection of moisture content in hazelnuts, hyperspectral image technology was utilized. A dataset comprising hyperspectral images of 200 hazelnuts covering wavelengths of 400~1 000 nm was collected, and the average spectral information of the hazelnuts image regions was extracted. The dataset was divided into sample validation and prediction sets using the K-S algorithm. Additionally, four preprocessing methods were applied to enhance spectra quality. Spectral features were extracted using a competitive adaptive weighting algorithm (CARS) and a successive projection method (SPA). Image texture features were obtained using the gray-scale co-occurrence matrix method (GLCM). Partial least squares regression (PLSR) and support vector regression (SVR) models were developed based on spectral features, image texture features, and the fusion of both to predict hazelnut moisture. The CARS and SPA algorithms effectively selected feature wavelengths and enhanced prediction performance. Furthermore, image features showed potential in predicting hazelnut moisture content, particularly when extracted from principal component images. The fusion of spectral and image features significantly enhances the accuracy of hazelnut moisture content prediction, especially when combining CARS-selected feature wavelengths with texture features from principal component images. The SVR model achieved impressive results, with an RMSECV of 0.03, RC of 0.97, RMSEP of 0.04, and RP of 0.96. This study highlights the effectiveness of hyperspectral image and texture features in predicting hazelnut moisture content, providing a novel approach for moisture detection in hazelnuts.

32 Quality Analysis of Physicochemical Properties of Rums Produced in Different Areas

MO Xingyou , HE Shanlian , WU Bin , YANG Guohuan , WU Fuhai , MO Tiansheng , SONG Fenyun , WU Shuai

2024, 40(5):282-289. DOI: 10.13982/j.mfst.1673-9078.2024.5.0677

[Abstract](83) [HTML](11) [PDF 3.71 M](268)

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To evaluate the safety and quality of Rum, 19 batches of Rums from five different origins (China, Cuba, Guatemala, Jamaica, and Philippines) were tested for physicochemical properties according to the relevant standards provided in the ‘People’s Republic of China Light Industry Standard -Rum’ and ‘National Food Safety Standard- Distilled Liquor and Compound Wine’ in this paper. The results showed that 12 out of 19 batches had a volume error of >1.0% between the measured and labeled values, with only 36.8% meeting the standard; The content of fixed and volatile acids ranged from 0.01 to 0.45 g/L and 0.02 to 0.42 g/L, respectively; The content of methanol, lead, and copper ranged from 0.012 to 0.061 g/L, 0.006 to 0.058 mg/L, and 0.011 to 0.157 mg/L, respectively; Cyanide was not detected in any samples; Levels of N-propanol, isobutanol, and primary active amyl alcohol were tested, and their contents ranged from 0.020 to 0.261 g/L, 0.06 to 0.149 g/L and 0.01~0.516 g/L, respectively, indicating overall low content. Levels of total nonalcoholic volatiles were 0.092~2.028 g/L, with a compliance rate of 73.7%. It can be seen that the main physicochemical properties of Rum produced in regular ways or purchased through regular channels basically meet the standard requirements and have a high safety level. The results of this research are of practical significance for consumers to gain a deeper understanding of the quality and safety of Rum, as well as for supervisory and managerial departments to realize scientific supervision and to promote the sound development of the Rum industry.

33 Research Progress on the Application of Flavoromics Technology in Dairy and Its Products

CHEN Han , REN Wei , SUN Lingyun , QIN Huaxiu , ZHU Mingxia , WANG Changfa , LI Mengmeng

2024, 40(5):290-298. DOI: 10.13982/j.mfst.1673-9078.2024.5.0657

[Abstract](136) [HTML](13) [PDF 3.12 M](723)

Abstract:
Milk and its products, as currently indispensable beverages, have many categories and unique odors. The characteristic flavors of milk, such as milky aroma, fruit aroma, sweetness, and acidity, are determined by volatile substances. Volatile substances (including alcohols, aldehydes, ketones, acids, esters, lactones, sulfur-containing compounds, nitrogen-containing compounds, and terpenoids) are mainly produced by microbial degradation in organisms and biochemical reactions during the ripening process. Flavoromics is an emerging field in omics technology that tracks and identifies food flavor compounds, explores the contribution to volatile components to food flavor and underlying working mechanisms. This article reviews the main flavor substances, components, and sources in milk, and determines the quality and texture of milk from the perspective of flavoromics technology, thereby providing a theoretical basis for flavor regulation of milk and its products.

34 Research Progress on the Changes in Color of Fruits and Vegetables during Thermal and Non-thermal Processing

XIE Zhanghui , GAO Jing

2024, 40(5):299-312. DOI: 10.13982/j.mfst.1673-9078.2024.5.0506

[Abstract](80) [HTML](8) [PDF 4.12 M](156)

Abstract:
Color is a very important apparent attribute of fruit and vegetable, which is highly related to the natural pigments contained in fruits and vegetables, and is one of the important indicators for judging whether their quality has changed. Thermal and non-thermal processing technologies are widely used in the processing of fruit and vegetable products. Traditional processing technology of fruit and vegetable are mainly thermal processing such as hot peeling, blanching, alkali peeling, drying and frying. The high temperature used in processing can easily cause irreversible effects on the color and quality of fruit and vegetable. In recent years, novel thermal and non-thermal processing technologies have been gradually explored. Non-thermal processing technologies such as enzymatic peeling, infrared treatment, ultrasonic treatment, pulsed electric field, high-pressure treatment and cold plasma have played a positive role in maintaining the color of fruit and vegetable processing. However, currently there are fewer discussions and comparative studies on the impact of the two processing technologies on the color of processed fruit and vegetable products, and it is of great significance to clarify the principle, conditions of use, process parameters, and advantages and disadvantages of each method for processing high-quality fruit and vegetable products. Therefore, this paper outlines the structural characteristics and physicochemical properties of each pigment, summarizes and compares the key technical points of thermal and non-thermal processing technologies and their effects on the color stability of fruits and vegetables. Finally, some suggestions are put forward to address the challenges during the processing of fruit and vegetable, to provide guidance for the application of thermal and non-thermal processing technologies in color preservation of fruits and vegetables.

35 Research Progress on the Effects of Physical Techniques on Starch Structure and Preparation of OSA-esterified Starch and Its Functional Properties

LI Dehai , WANG Nannan , YANG Fan , WANG Zetong , BAO Yihong , WANG Peng

2024, 40(5):313-324. DOI: 10.13982/j.mfst.1673-9078.2024.5.0619

[Abstract](84) [HTML](13) [PDF 6.31 M](364)

Abstract:
Starch is a widely available and versatile resource, but its natural properties have limitations that restrict its applications. Therefore, research surrounding modified starch has drawn significant attention. Studies have shown that octenyl succinic anhydride (OSA)-esterified starch exhibits unique amphiphilicity, improving its hydrophobicity and emulsifying properties. However, the efficiency of traditional methods for preparing OSA-esterified starch is low, and the functional properties of esterified starch do not meet optimal application requirements. Consequently, the preparation of high-quality esterified starch has remained a research focus. In recent years, physical techniques have been widely used as environmentally friendly and efficient methods for modifying starch. Pretreating natural starch with physical techniques has been to facilitate the preparation of esterified starch. The disruption of starch granule structure by physical techniques increases the number of esterification sites and improves esterification efficiency. Furthermore, the functional properties of esterified starch can be further improved by pretreatment with physical techniques, thereby promoting its practical applications. This article summarizes research concerning six physical techniques, including ultrasonication, pulsed electric fields, high hydrostatic pressure, atmospheric plasma jets, dynamic high-pressure microfluidization, and ball milling, for the preparation of OSA-esterified starch. The basic principles of these physical techniques are overviewed, and their effects on the structure, preparation, and functional properties of starch and OSA-esterified starch are discussed.

36 Research Progress on the Influence of Pulsed Intense Light Technology on Food Processing Quality and Safety Control Technology

FU Chuanhan , YANG Haihua , LI Yu , DONG Guannan , WANG Zhouli

2024, 40(5):325-338. DOI: 10.13982/j.mfst.1673-9078.2024.5.0797

[Abstract](73) [HTML](10) [PDF 4.27 M](147)

Abstract:
Pulsed intense light is a kind of emerging non-heat treatment technology. The device allows theionization of rare gases to release high-energy pulsed light to reduce the microbial load on a solid surface or liquid food, so as to prolong the shelf life of food This technique does not cause obvious damage to various nutrients, and can also improve certain food physico-chemical properties and sensory quality, which makes up for the defects of traditional thermal sterilization methods and chemical sterilization methods. The photochemical and photothermal effects of pulsed intense light are considered to be the main mechanisms for reducing microbial load in food. Based on comprehensive research on various aspects, pulsed intense light technology has achieved good outcomes in food processing and safety control. This article mainly reviews the application progress of pulsed intense light technology in food processing and safety control, and evaluates the changes in some physico-chemical indexes of food quality caused by different pulsed intense light treatments. Finally, the prospect of pulsed intense light technology and some deficiencies of the technology are provided, which offers a reference for the wide application of pulsed intense light technology in the food industry.

37 Research Progress on Sweet Potato Puree as a Food for Dysphagia

CAO Xingyao , SUN Hongnan , MU Taihua

2024, 40(5):339-346. DOI: 10.13982/j.mfst.1673-9078.2024.5.0428

[Abstract](86) [HTML](10) [PDF 3.20 M](147)

Abstract:
As a safe food for patients with dysphagia, texture-modified food has the characteristics such as soft texture and safe swallowing, and meets the nutritional needs of patients. Different countries have different classifications of foods for dysphagia, and most of them focus on the texture properties of the food itself. In recent years, the dietary safety of patients with dysphagia has received much attention, and research on the development of foods for dysphagia has gradually increased. Sweet potato puree a pureed food made from fresh sweet potatoes through a series of processing, and retains the majority of the nutrients in sweet potatoes, and has the characteristics such as softness and high contents of nutrients, thereby being considered as a high-quality raw material for texture modified foods suitable for patients with dysphagia. However, the texture properties of sweet potato puree are influenced by various factors, such as raw materials for processing, processing techniques, and storage conditions, which limit the application of sweet potato puree as a food for dysphagia in the food field. This article review the classification of texture-modified foods, the processing of sweet potato puree, and the research on the texture properties of sweet potato puree, aiming to provide a theoretical basis for the development and application of sweet potato puree products suitable for patients with dysphagia.

38 Research Progress on Sources, Distribution Characteristics and Toxicology of Microplastics in Foods

WANG Huiping , WANG Zhen , FENG Zhiqiang , ZHANG Xinrui , WANG Luyang , HUANG Jihong

2024, 40(5):347-358. DOI: 10.13982/j.mfst.1673-9078.2024.5.0384

[Abstract](95) [HTML](12) [PDF 3.04 M](232)

Abstract:
Food has become the main source of ingested microplastics (MPs) by the human body. MPs in food mainly come from food raw materials (including fish, shellfish, crops, salt and water, etc.), food processing and food packaging. The distribution characteristics of MPs in food such as abundance, shape, particle size and polymer type are related to factors such as geographical location, human activities and type of food industry. Currently, detection methods for MPs include scanning electron microscopy and energy dispersive x-ray spectroscopy (SEM-EDS), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy (RS), thermal analysis coupled with gas chromatography-mass spectrometry (GC-MC), and a combination of these methods. In addition, the chemical additives inherent in MPs, pollutants adsorbed from the environment, and harmful microbial adhesion can pose health risks to the human body, including direct toxicity, translocation toxicity and compound toxicity. Studies have confirmed that inflammation, oxidative stress, apoptosis and mitochondrial dysfunction are closely related to MPs intake. This article reviews the sources, distribution characteristics, detection methods, and toxicological effects of MPs contamination in food, which ultimately provides a reference for the prevention and control of MPs in food as well as future research.

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Volume 0,Issue 5,2024 Table of Contents