DFD牛肉潜在生物标志物的筛选

发布时间：2021-10-20 00:22

　　DFD（Dark firm dry）肉是与宰后代谢异常有关的主要劣质肉之一。因为色泽深,被消费者认为是来自年龄大或未经良好加工的畜禽,肉嫩度差、味道不好、货架期短。DFD肉一直是肉品科学研究的热点,但其确切的生物化学机制和生物标志物尚不清楚,目前在牛肉生产过程中发生率较高并造成重大经济损失。为了筛选DFD肉的潜在生物标志物,本研究开展了以下四个实验。本研究分析了DFD肉的品质,研究了肉色与其他品质性状的相关关系。根据宰后24 h的pH值将背最长肌（LT）分为正常肉（pH≤5.70）、非典型DFD肉（5.70<pH≤6.09）和典型DFD肉（pH>6.09）三组。4℃条件下保存7 d,用于4个研究。典型DFD肉在宰后1 d时糖酵解潜力、L^*、a^*、b^*、色度和氧肌红蛋白值最低,持水力、色度角和脱氧肌红蛋白值最高。糖酵解潜力与色度、R630/580、氧肌红蛋白呈正相关,与pH、色度角呈负相关。持水力与脱氧肌红蛋白水平直接相关。非典型DFD肉剪切力值较高,与肌红蛋白水平呈正相关。总之,DFD肉糖酵解潜能受损,DFD... 

【文章来源】：中国农业科学院北京市

【文章页数】：106 页

【学位级别】：博士

【文章目录】：
摘要
Abstract
Abbreviations
CHAPTER1 INTRODUCTION
    1.1 MEAT QUALITY
        1.1.1 Concept of meat quality
        1.1.2 Factors contributing to meat quality
        1.1.3 Meat quality defects
        1.1.4 Dark Firm Dry(DFD)meat
    1.2 IDENTIFICATION OF MEAT QUALITY
        1.2.1 Concept of biomarkers
        1.2.2 Biomarkers of meat quality
        1.2.3 Technologies to detect biomarkers
        1.2.4 Identification of DFD meat
    1.3 PROTEIN PHOSPHORYLATION AND MEAT QUALITY
        1.3.1 Current research of protein phosphorylation on meat quality
        1.3.2 Role of protein phosphorylation on meat quality identification
    1.4 AIMS AND TECHNICAL ROUTE OF THE RESEARCH
        1.4.1 Aims
        1.4.2 Technical route
CHAPTER2 UNDERSTANDING THE QUALITY OF DFD BEEF TO INVESTIGATE THE RELATIONSHIP OF COLOR WITH OTHER QUALITY ATTRIBUTES
    2.1 INTRODUCTION
    2.2 MATERIALS AND METHODS
        2.2.1 Animals grouping and sample collection
        2.2.2 p H measurement
        2.2.3 Instrumental color measurement
        2.2.4 Determination of myoglobin redox forms
        2.2.5 Shear force and cooking loss measurement
        2.2.6 Water-holding capacity measurement
        2.2.7 Glycolytic potential measurement
        2.2.8 Statistical analysis
    2.3 RESULTS
        2.3.1 Change in the p H values
        2.3.2 Instrumental color measurement
        2.3.3 Change in myoglobin redox forms
        2.3.4 Shear force,cooking loss and water-holding capacity
        2.3.5 Glycolytic potential
        2.3.6 Multivariate statistical analysis
    2.4 DISCUSSION
    2.5 SUMMARY
CHAPTER3 COMPARATIVE PROFILING OF SARCOPLASMIC AND MYOFIBRILLAR PHOSPHOPROTEINS OF DFD BEEF
    3.1 INTRODUCTION
    3.2 MATERIALS AND METHODS
        3.2.1 Collection of samples
        3.2.2 Protein extraction
        3.2.3 Gel electrophoresis
        3.2.4 Staining and image analysis
        3.2.5 Protein phosphorylation calculation
        3.2.6 Identification of proteins by LC-MS/MS
        3.2.7 Statistical analysis
    3.3 RESULTS
        3.3.1 Global phosphorylation level of sarcoplasmic proteins
        3.3.2 Phosphorylation level of individual sarcoplasmic proteins band
        3.3.3 Identification of phosphorylated sarcoplasmic proteins
        3.3.4 Global phosphorylation level of myofibrillar proteins
        3.3.5 Phosphorylation level of individual myofibrillar proteins band
        3.3.6 Identifications of phosphorylated myofibrillar protein
    3.4 DISCUSSION
        3.4.1 Phosphorylation of sarcoplasmic protein
        3.4.2 Phosphorylation of myofibrillar proteins
    3.5 SUMMARY
CHAPTER4 METABOLOMIC APPROACH TO INVESTIGATE THE BIOCHEMICAL BASIS LINKED WITH THE OCCURRENCE OF DFD BEEF
    4.1 INTRODUCTION
    4.2 MATERIALS AND METHODS
        4.2.1 Collection of samples
        4.2.2 Preparation of samples
        4.2.3 UHPLC analysis conditions
        4.2.4 Q-TOF/MS analysis conditions
        4.2.5 Data Analysis
    4.3 RESULTS
        4.3.1 Comparison of total ion chromatogram(TIC)of the samples
        4.3.2 Correlation and MCC spectra of QC samples
        4.3.3 Multivariate statistical analysis
        4.3.4 Identification of differential metabolites
    4.4 DISCUSSION
    4.5 SUMMARY
CHAPTER5 ROLE OF HEAT SHOCK PROTEINS IN DETERMINATION OF POSTMORTEM METABOLISM AND DEVELOPMENT OF MEAT QUALITY OF DFD BEEF
    5.1 INTRODUCTION
    5.2 MATERIALS AND METHODS
        5.2.1 Collection of samples
        5.2.2 Measurement of meat p H
        5.2.3 Evaluation of meat color and shear force
        5.2.4 Measurement of water-holding capacity of samples
        5.2.5 Determination of glycogen content
        5.2.6 Determination of lactate content
        5.2.7 Sarcoplasmic protein extraction
        5.2.8 Sodium dodecyl sulphate polyacrylamide gel electrophoresis(SDS-PAGE)
        5.2.9 Immunoblot analysis
        5.2.10 Statistical analysis
    5.3 RESULTS
        5.3.1 Meat quality and glycolytic metabolite measurements
        5.3.2 Expression of HSP27,HSP70 and HSP90
        5.3.3 Relationship of HSPs with meat quality and glycolytic metabolite
    5.4 DISCUSSION
        5.4.1 Meat quality and glycolytic metabolites
        5.4.2 Change in expression of heat shock proteins
        5.4.3 Role of HSPs in DFD meat identification
    5.5 SUMMARY
CHAPTER6 CONCLUSIONS AND PROSPECTS
    6.1 CONCLUSIONS
    6.2 PROSPECTS
REFERENCES
ACKNOWLEDGEMENTS
RESUME
PUBLICATIONS



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