Effects of Heat Treatment on Processing Characteristics of Pork

[Objectives]This study was conducted to explore the effects of heat treatment on processing characteristics of pork.[Methods]The effects of low-temperature long-term cooking(LTLT),high-temperature vacuum cooking,high-temperature cooking and high-temperature steaming on some indexes of pork products were studied,and principal component analysis was carried out.[Results]LTLT had significant effects on the total sensory score,moisture content,cooking loss rate,a value,shear force,and TBARS of pork,and the corresponding optimal product indicators were 71.40 points,72.36%,14.20%,4.79,7089.87 g,and 0.05 mg/kg,respectively.The microstructure changes in the LTLT group were relatively small,as the muscle fiber structure was relatively dense and uniform,and the gaps between muscle fibers were small.A total of 30 volatile flavor compounds were detected in the four groups,mainly alcohols,alkenes,alkanes,lipids,ketones,and aldehydes,and the LTLT group had more types and high contents.PCA analysis showed that the sensory evaluation,moisture content,elasticity,a value and LTLT were positively correlated with principal component 1.[Conclusions]Various indexes comprehensively showed that the LTLT group had better meat color,flavor,texture characteristics and lower oxidation degree than traditional cooking and steaming methods,which provides a theoretical reference for its large-scale application in the processing of prepared meat products.

Teaching Reform and Practice of Animal Products Processing under the Background of Intelligent Agriculture

Effective food professional personnel training strategies are explored and implemented,and interdisciplinary talents of food science and engineering in accordance with the background of intelligent agriculture are cultivated from the aspects of construction of teaching staff,reform of teaching content,upgrading of teaching model,construction of industry-education integration platform,which is of great significance to the modernization development of Chinese animal products processing industry.

Practical Exploration of Online Teaching of Animal Product Processing

Online teaching has become an important part of higher education due to the continuous effects of the global COVID-19. In this paper, the online teaching of Animal Product Processing was designed and implemented from three aspects of optimization of online teaching content, organization of teaching process and implementation of online assessment. According to the analysis of the questionnaire survey and the final evaluation results, the online teaching of Animal Product Processing is well received by the students and has achieved good teaching results, providing a useful reference for colleges and universities to carry out in-depth online teaching of Animal Product Processing.

Evaluation of the binding affinity and antioxidant activity of phlorizin to pepsin and trypsin

Phlorizin(PHL)is a natural compound with strong antioxidant properties mainly found in apples.In this paper,the interaction mechanism of PHL with pepsin and trypsin was comparatively evaluated by computer simulation,fluorescence spectra,circular dichroism(CD),and Fourier transform infrared(FT-IR)spectra at a molecular level.Fluorescence spectra showed that PHL quenches the pepsin/trypsin by static quenching.Thermodynamic parameters indicated that PHL binds to pepsin mainly through hydrogen bonds and van der Waals forces,and that of trypsin was electrostatic forces.The ground state complexes PHL and protease have a moderate affinity of 105 L/mol PHL binds more strongly to trypsin than to pepsin.CD and FT-IR spectra results showed that pepsin/trypsin decreased theβ-sheet content and slightly changed its secondary structure upon PHL.These experimental results are mutually verified with the predicted computer-aid simulation results.Upon PHL and trypsin binding,the antioxidant capacity of PHL was elevated.Nevertheless,the antioxidant capacity of PHL was decreased after binding to pepsin.This work elucidates the binding of PHL binding mechanisms to pepsin/trypsin and provides useful information for the digestion of PHL to improve the application of PHL in food processing.

Effects of potassium lactate on sensory attributes,bacterial community succession and biogenic amines formation in Rugao ham

To deepen the understanding in the effect of potassium lactate on the sensory quality and safety of Rugao ham,sensory attributes,physicochemical parameters,total volatile basic nitrogen(TVBN),microorganism community and biogenic amines of Rugao ham manufactured with different potassium lactate levels(0%,0.5%,1%,2%)were investigated;the relationship between microbial community and the formation of TVBN and biogenic amines was further evaluated.With the increase of potassium lactate from 0%to 2%,the increased sensory scores and the decreased total aerobic bacterial count and TVBN were observed;the abundance of Staphylococcus increased,while the content of Halomonas decreased.LDA effect size(LEf Se)and correlations analysis showed that Staphylococcus equorum and Lactobacillus fermentum could be the key species to improve sensory scores and decrease biogenic amines and TVBN.Metabolic pathway analysis further showed that amino acids metabolism and nitrogen metabolism were mainly involved in decreasing TVBN and biogenic amines in the treatment of 2%potassium lactate.

Impact of Low-temperature Storage on Volatile Flavor Compounds in Prepared Pork Products

[Objectives]This study was conducted to explore the dynamic changes of volatile flavor compounds in prepared pork during storage at different low-temperature conditions.[Methods]Prepared pork was stored at 4,-4 and-18℃.The volatile flavor compounds of prepared pork were determined by solid-phase microextraction-gas chromatography-mass spectrometry(SPME-GC-MS)at days 0,7,14,21 and 28,and relative odor activity value(OAV),principal component analysis(PCA)and cluster analysis(CA)were combined to analyze changes in volatile flavor compounds of prepared pork during storage.[Results]The total number of volatile flavor compounds gradually decreased with the prolongation of the storage period,and OAV analysis identified 22 key flavor compounds(OAV≥1).The results of PCA and CA showed that 2-methyl-1-butanol,1-octen-3-ol,linalool,cineole,hexanal and nonanal were the main key flavor components,and the degree of flavor degradation was low under both superchilling and freezing conditions.After 28 days of storage,the alcohol content in the chilling group was significantly higher than other two groups,and the overall content of volatile flavor compounds was also significantly higher than other two groups,indicating that the-4℃chilling storage was more favorable for maintaining the overall flavor of prepared pork.[Conclusions]This study provides a theoretical basis for finding a better storage method for prepared meat products.

Enhanced Production of Natural Carotenoids from Genetically Engineered Rhodobacter sphaeroides Overexpressing CrtA

Carotenoids act as precursors of vitamin A,antioxidants,enhancers of immunity,and are thus widely used in food and pharmaceutical industry.Microbial fermentation is one of the most important solutions for production of natural carotenoids.Rhodobacter sphaeroides is one of most promising bacteria employed for large scale production of carotenoids.In the present study,crtA located in the carotenoids biosynthesis pathway in R.sphaeroides was amplified by PCR.The overexpression vector pRKcrtA was constructed and subsequently transferred into R.sphaeroides,producing the genetically engineered strain R.sphaeroides 2.4.1/pRKcrtA overexpressing crtA.The carotenoid production from the genetically engineered strain was significantly increased.Fermentation procedure was optimized for further enhanced carotenoids production.

Mycotoxins in Chinese Traditional Cured Meats: A Review

Chinese cured meats are popular in the world,which are not only meat products but also cultures in China.Fungi can grow on the surface of the traditional cured meats easily during the processing and storage.Some fungi contribute to the specific flavors,color and sensory characteristics of cured meats,while others produce mycotoxins like aflatoxins,ochratoxins,and deoxynivalenol,which will lead to cancer.Although the mycotoxins limits in food have been published by national standard in China,the limits in cured meats are still in blank.Therefore,it is reasonable to identify and reduce the mycotoxins in Chinese cured meats and meat products.This review analyzed the causes of mycotoxins,identification and control methods for Chinese cured meats.

The role of flavonoids in mitigating food originated heterocyclic aromatic amines that concerns human wellness

Meat products are an important part in our daily diet,providing valuable nutrients for the human body.However,heating processes cause the meat to become more appetizing with changes in texture,appearance,flavor,and chemical properties by the altering of protein structure and other ingredients.As one kind of cooking-induced contaminants,heterocyclic aromatic amines(HAAs)are widely present in protein aceous food products with strong carcinogenic and mutagenic properties.In order to promote the safety of traditional meat products,this review focused on the formation,metabolism,biological monitoring and inhibitory mechanism of HAA.An overview of the formation pathways,hazards,and control methods of HAAs during food processing in recent years was studied,aiming to provide some valuable information for exploring effective methods to inhibit the production of associated hazards during food processing.Systematic selection of different types of flavonoids to explore their effects on the formation of HAAs in an actual barbecue system can provide theoretical reference for effectively controlling the formation of HAAs and reducing their harm to human health.

Transcriptome-based insights into the calcium transport mechanism of chick chorioallantoic membrane

Chorioallantoic membrane(CAM)is responsible for respiratory gas exchange,eggshell calcium transport,embryonic acid-base equilibrium,allantoic ion,and water reabsorption during avian embryonic development.To further understand the timing of CAM gene expression during chick embryonic development,especially the calcium absorption mechanism,transcriptome quantitative comparative analysis was conducted on chick CAM during the embryonic period(E)of 9,13,17,and 20 days.A total of 6378 differentially expressed genes(DEGs)were identified.Functional enrichment analysis of DEGs showed that CAM DEGs were mainly involved in biological processes such as"ion transport regulation","immune response"and"cell cycle".Time series analysis of the differential genes showed that the functional cells of CAM began to proliferate and differentiate at E9 and the calcium content of egg embryo increased significantly at E13.Simultaneously,the observation of the ultrastructure of the eggshell showed that the interstice of the fiber layer was enlarged at E13,and the mastoid layer was partly exposed.Therefore,it is preliminarily inferred that CAM calcium transport starts at E13,and genes such as TRPV6,S100 A10,and RANKL cooperate to regulate calcium release and transport.

Suggestions on Curriculum Reform of Food Major in the Context of Educational Reform

The food major is an application-oriented major that involves a wide range of professional knowledge and disciplines,and provides applied talents with food production,inspection,and sales skills to the society.With the rapid development of society,the demand of social employers for talents also shows a diversified trend.For the cultivation of food professionals in the new era,it is necessary to improve their innovative spirit and practical ability,in order to adapt to the diverse development needs of society.Under the background of education reform,this paper briefly analyzed the teaching strategies of food major,and put forward specific reform suggestions,hoping to promote education reform to effectively promote the sustainable development of food major,and effectively improve the quality of education.

Optimization of Coenzyme Q10Production Procedure from Genetic Engineered Rhodobacter sphaeroides Overexpressing UbiG

In the present study, single factors including fermentation temperature, inoculate amount, fermentation duration, and ratio of fermentation medium volume to total flask volume(dissolved oxygen tension) were optimized for enhancing the production of coenzyme Q10 from genetic engineered Rhodobacter sphaeroides overexpressing UbiG. The experimental results suggested that optimal single factors were: inoculate amount 2%, fermentation temperature 30 ℃, fermentation duration 48 h, and ratio of fermentation medium volume to total flask volume 80%. The present study will promote the large scale production of CoQ10 from microorganisms.

Small cell lung carcinoma with KIF5B-RET fusion partially responded to the 4^(th)-line therapy with anlotinib:A case report

BACKGROUND Small cell lung cancer(SCLC)exhibits a pronounced tendency for metastasis and relapse,and the acquisition of resistance to chemotherapy and radiotherapy,leading to complexity in treatment outcomes.It is crucial to tackle these challenges by advancing targeted therapeutic approaches in ongoing research endeavors.Variant RET fusions have been reported in several solid tumors,but are rarely reported in SCLC.CASE SUMMARY We present the first case of a KIF5B-RET fusion in a 65-year-old male patient with SCLC.To date,the patient has received the 4th line chemotherapy with anlotinib for one year and has shown a sustained favorable partial response.According to the results of next generation sequencing,this SCLC patient harbors the KIF5BRET fusion,suggesting that RET fusion could serve as a promising molecular target for SCLC treatment.Next-generation sequencing(NGS)plays a critical rolein comprehensively assessing the genotype and phenotype of cancer.CONCLUSION NGS can provide SCLC patients with personalized and targeted therapy options,thereby improving their likelihood of survival.

Insight into the relationship between microorganism communities and flavor quality of Chinese dry-cured boneless ham with different quality grades

Microorganisms played a key role in developing the flavor quality,while few studies focused on the relationship between microbial diversity and flavor quality of dry-cured boneless ham.To explore the relationship,sensory evaluation,lipases,microorganism communities,free fatty acids and volatile compounds were investigated in dry-cured boneless ham with different quality grades(NS,WS and GS groups);the correlation between cored microbes and crucial volatiles was further evaluated by metabolic network analysis.GS group showed the highest scores in aroma and overall acceptance among three groups.The highest values of phospholipase activities(7.88 U*g−1 protein)were shown in GS group,while the lowest values of TBARS(0.93 mg/kg)were observed in GS among three groups.High-throughput sequencing revealed that fungi showed the most various among three groups;Xerochrysium,Aspergillus,Penicillium and Debaryomyces were the most genera in GS.SPME-GC-MS revealed that GS showed higher contents and numbers in volatiles than other groups;aldehydes and furans were intensely response to the variations of volatiles among these groups.Metabolic pathway further revealed that several key species derived from Penicillium and Aspergillus accelerated the formation of volatiles byβ-lipoxidation and Strecker degradation.These results indicated that molds could be the major contributors in developing and differentiating the flavor quality of Chinese dry-cured boneless ham.