枣粉吸湿与吸湿改善作用机制及吸湿前后生物利用度研究
发布时间：2020-12-07 19:48
红枣,作为中国特色果品资源,具有丰富的营养和保健价值。干燥是红枣的主要加工方式,枣粉是其主要产品形式之一。然而,枣粉在快速干燥过程中呈现无定形态,当暴露到外部环境中其易吸湿结块,从而影响产品的商业价值。目前,已有添加抗结块剂用于改善枣粉的吸湿特性。此外,吸湿对枣粉中的生物活性成分如多酚、黄酮类等物质也会有显著影响。本文主要结论如下:采用粉末流变仪定量分析了真空冷冻干燥（FD）、红外干燥（IR）、压差闪蒸联合干燥（DIC）、热泵干燥（HP）及热风干燥（HA）等5种不同干燥方式对枣粉结块的影响。结果表明,枣粉吸湿过程为非同步吸湿过程。干燥方法对枣粉的结块有显著影响,FD和DIC处理的枣粉在25℃,75%RH下分别表现出最高和最低的结块强度（622和170mJ/g）。结块强度随着相对湿度和加载压力的增加而增加。温度和时间对粉末结块具有耦合作用,较高的温度可显着加速粉末的结块强度。当枣粉的含水量在25℃时超过0.066g/g时,会发生玻璃化转变。枣粉的结构将从“无定形玻璃状”变为“无定形橡胶状”。颗粒的结块主要是由于烧结桥的形成,果糖是枣粉结块的主要原因之一。为了降低枣粉的结块程度,添加2%w...
【文章来源】：中国农业科学院北京市
【文章页数】：95 页
【学位级别】：硕士
【文章目录】：
附表
摘要
Abstract
Abbreviation
CHAPTER 1 BACKGROUND
1.1 Introduction
1.2 Germplasm resources of jujube
1.3 Bioactive and nutritional components
1.4 Drying technology of jujube
1.5 Caking of jujube powders
1.6 Effect of anticaking agents on caking of jujube powders
1.7 Bioaccessibility of bioactive compounds of jujube powder
1.8 Aim and objectives
1.9 Research funding
1.10 Technical route
CHAPTER 2 UNDERSTANDING THE CAKING BEHAVIOR OF AMORPHOUS JUJUBE POWDER BY POWDER RHEOMETER
2.1 Introduction
2.2 Materials and methods
2.2.1 Materials
2.2.2 Jujube powder preparation
2.2.3 Moisture content and water activity determination
2.2.4 Particle size distribution
2.2.5 Glass transition temperature
2.2.6 Moisture sorption behavior
2.2.7 Scanning Electron Microscope（SEM）
2.2.8 Powder X-ray Diffraction（PXRD）measurement
2.2.9 Sugar content analysis
2.2.10 Assessment of jujube powder caking by powder rheometer
2.2.11 Statistical analysis
2.3 Results and discussions
2.3.1 Effect of different drying methods on caking of jujube powders
2.3.2 Moisture sorption behavior
2.3.3 Caking of jujube powders
2.3.4 Effect of different factors on caking of DIC jujube powders
2.3.5 Effect of particle size on caking of jujube powders
2.3.6 Understanding caking behavior based on glass transition and particle morphology
2.3.6.1 Glass transition
2.3.6.2 Powder X-ray Diffractometer（PXRD）
2.3.6.3 HPLC analysis
2.3.6.4 SEM
2.4 Summary
CHAPTER 3 ASSESSMENT OF ANTICAKING AGENT ON CAKING BEHAVIOR OF JUJUBE POWDER VIA POWDER RHEOMETER AND BALL INDENTAION
3.1 Introduction
3.2 Materials and methods
3.2.1 Materials and chemicals
3.2.2 Jujube powder preparation and powders mixing
3.2.3 Moisture content
3.2.4 Particle size distribution
3.2.5 Glass transition determination and modelling by differential scanning calorimeter（DSC）
3.2.6 Dynamic moisture sorption
3.2.7 Powder X-ray Diffraction（PXRD）measurement
3.2.8 Assessment of caking behaviour using powder rheometer
3.2.9 Scanning Electron Microscope（SEM）
3.2.10 Statistical analysis
3.3 Results and discussions
3.3.1 Moisture sorption behavior of jujube powder and blends
3.3.2 Flowability and caking behaviors
3.3.3 Effect of mixing time,mixing speed and calcium stearate concentration on caking of jujube powders
3.3.4 Effect of temperature and time on caking of jujube powders
3.3.5 PXRD patterns of jujube with calcium stearate
3.3.6 State diagram analysis
3.3.7 SEM
3.4 Summary
CHAPTER 4 BIOACCESSIBILITY AND ANTIOXIDANT ACTIVITIES OF BIOACTIVE COMPOUNDS OF JUJUBE POWDERS BEFORE AND AFTER CAKING
4.1 Introduction
4.2 Materials and Methods
4.2.1 Materials and Chemicals
4.2.2 Determination of total phenolic content,total flavonoids and antioxidant capacity
4.2.2.1 Extractions
4.2.2.2 Total phenolic content
4.2.2.3 Total flavonoid content
4.2.2.4 Antioxidant activities
4.2.3 Simulated in vitro gastrointestinal digestion of jujube powder
4.2.4 Assessment of bioaccessibility
4.2.5 HPLC analysis of phenolic compounds
4.2.6 Statistical analysis
4.3 Results and discussion
4.3.1 Total phenolic and total flavonoid content of jujube powders prior to digestion
4.3.2 Antioxidant capacity of jujube powders prior to digestion
4.3.3 Changes in total phenolic and total flavonoid content during in vitro gastrointestinal digestion
4.3.4 Changes in total antioxidant capacity during in vitro gastrointestinal digestion
4.3.5 Bioacessibility of total phenolic and flavonoid content
4.3.6 Quantification of phenolic compounds by HPLC
4.4 Summary
CHAPTER 5 CONCLUSION
REFERENCES
ACKNOWLEDGEMENT
RESUME
PUBLICATIONS
本文编号：2903808
【文章来源】：中国农业科学院北京市
【文章页数】：95 页
【学位级别】：硕士
【文章目录】：
附表
摘要
Abstract
Abbreviation
CHAPTER 1 BACKGROUND
1.1 Introduction
1.2 Germplasm resources of jujube
1.3 Bioactive and nutritional components
1.4 Drying technology of jujube
1.5 Caking of jujube powders
1.6 Effect of anticaking agents on caking of jujube powders
1.7 Bioaccessibility of bioactive compounds of jujube powder
1.8 Aim and objectives
1.9 Research funding
1.10 Technical route
CHAPTER 2 UNDERSTANDING THE CAKING BEHAVIOR OF AMORPHOUS JUJUBE POWDER BY POWDER RHEOMETER
2.1 Introduction
2.2 Materials and methods
2.2.1 Materials
2.2.2 Jujube powder preparation
2.2.3 Moisture content and water activity determination
2.2.4 Particle size distribution
2.2.5 Glass transition temperature
2.2.6 Moisture sorption behavior
2.2.7 Scanning Electron Microscope（SEM）
2.2.8 Powder X-ray Diffraction（PXRD）measurement
2.2.9 Sugar content analysis
2.2.10 Assessment of jujube powder caking by powder rheometer
2.2.11 Statistical analysis
2.3 Results and discussions
2.3.1 Effect of different drying methods on caking of jujube powders
2.3.2 Moisture sorption behavior
2.3.3 Caking of jujube powders
2.3.4 Effect of different factors on caking of DIC jujube powders
2.3.5 Effect of particle size on caking of jujube powders
2.3.6 Understanding caking behavior based on glass transition and particle morphology
2.3.6.1 Glass transition
2.3.6.2 Powder X-ray Diffractometer（PXRD）
2.3.6.3 HPLC analysis
2.3.6.4 SEM
2.4 Summary
CHAPTER 3 ASSESSMENT OF ANTICAKING AGENT ON CAKING BEHAVIOR OF JUJUBE POWDER VIA POWDER RHEOMETER AND BALL INDENTAION
3.1 Introduction
3.2 Materials and methods
3.2.1 Materials and chemicals
3.2.2 Jujube powder preparation and powders mixing
3.2.3 Moisture content
3.2.4 Particle size distribution
3.2.5 Glass transition determination and modelling by differential scanning calorimeter（DSC）
3.2.6 Dynamic moisture sorption
3.2.7 Powder X-ray Diffraction（PXRD）measurement
3.2.8 Assessment of caking behaviour using powder rheometer
3.2.9 Scanning Electron Microscope（SEM）
3.2.10 Statistical analysis
3.3 Results and discussions
3.3.1 Moisture sorption behavior of jujube powder and blends
3.3.2 Flowability and caking behaviors
3.3.3 Effect of mixing time,mixing speed and calcium stearate concentration on caking of jujube powders
3.3.4 Effect of temperature and time on caking of jujube powders
3.3.5 PXRD patterns of jujube with calcium stearate
3.3.6 State diagram analysis
3.3.7 SEM
3.4 Summary
CHAPTER 4 BIOACCESSIBILITY AND ANTIOXIDANT ACTIVITIES OF BIOACTIVE COMPOUNDS OF JUJUBE POWDERS BEFORE AND AFTER CAKING
4.1 Introduction
4.2 Materials and Methods
4.2.1 Materials and Chemicals
4.2.2 Determination of total phenolic content,total flavonoids and antioxidant capacity
4.2.2.1 Extractions
4.2.2.2 Total phenolic content
4.2.2.3 Total flavonoid content
4.2.2.4 Antioxidant activities
4.2.3 Simulated in vitro gastrointestinal digestion of jujube powder
4.2.4 Assessment of bioaccessibility
4.2.5 HPLC analysis of phenolic compounds
4.2.6 Statistical analysis
4.3 Results and discussion
4.3.1 Total phenolic and total flavonoid content of jujube powders prior to digestion
4.3.2 Antioxidant capacity of jujube powders prior to digestion
4.3.3 Changes in total phenolic and total flavonoid content during in vitro gastrointestinal digestion
4.3.4 Changes in total antioxidant capacity during in vitro gastrointestinal digestion
4.3.5 Bioacessibility of total phenolic and flavonoid content
4.3.6 Quantification of phenolic compounds by HPLC
4.4 Summary
CHAPTER 5 CONCLUSION
REFERENCES
ACKNOWLEDGEMENT
RESUME
PUBLICATIONS
本文编号：2903808
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