Fundamentals and Application of Atomic Force Microscopy for Food Research

Front Cover
Fundamentals and Application of Atomic Force Microscopy for Food Research
Copyright Page
Contents
List of contributors
1 Introduction of AFM for food research
1 An introduction
Acknowledgements
References
2 Fundamentals of AFM
2 Atomic force microscopy: from theory to application in food science
2.1 History of atomic force microscopy
2.2 Basic principles of atomic force microscopy
2.2.1 Basic components
2.2.2 Working conditions, basic functions, and theory
2.3 Force measurements and nanomanipulation
2.4 New imaging modes
2.5 Measurement items
2.6 Atomic force microscopy integration with other instruments
2.7 Research ways and applications
2.7.1 Research type
2.7.2 Quick overview of applications in food sciences
2.8 Conclusion
References
3 Operation procedures of atomic force microscopy for food and biological samples
3.1 Introduction
3.2 Atomic force microscopy requirements for food samples
3.3 Substrates
3.3.1 Mica
3.3.2 Glass
3.3.3 Graphite
3.4 Sample preparation for food samples
3.4.1 Individual biomolecules
3.4.2 Artificially supported lipid layers
3.4.3 Cells
3.4.4 Food powder
3.4.5 Bulk solid sample
3.5 Cantilever selection
3.5.1 Spring constant
3.5.2 Tip geometry
3.5.3 Resonance frequency and quality factor
3.5.4 Tip functionalization
3.6 Common imaging procedure by atomic force microscopy
3.6.1 Power on system
3.6.2 Mount sample
3.6.2.1 Prepare the sample
3.6.2.2 Load the sample
3.6.3 Mount probe
3.6.3.1 Mount the probe holder to the atomic force microscopy head
3.6.4 Enable software
3.6.5 Align laser
3.6.5.1 Align the laser spot on the front end of the cantilever
3.6.5.2 Maximize the laser SUM signal
3.6.6 Adjust photodiode signal
3.6.7 Cantilever tune (tapping mode only)
3.6.8 Set Initial scan parameters
3.6.9 Engage atomic force microscopy probe
3.6.9.1 Manually engage the atomic force microscopy probe
3.6.9.2 Automatically engage the atomic force microscopy probe
3.6.10 Optimize scan parameters
3.6.11 Acquire and save the image
3.6.12 Withdraw atomic force microscopy probe
3.6.13 Unmount atomic force microscopy probe and sample
3.6.14 Shutdown system
3.6.15 Clean workspace
3.7 Common force measurement procedure by atomic force microscopy
3.7.1 Measure deflection sensitivity
3.7.2 Calculate spring constant
3.7.2.1 Thermal tune method
3.7.2.2 Sader method
3.7.3 Force measurement
3.8 Common nanomanipulation procedure by atomic force microscopy
3.9 Data optimization
3.9.1 Real-time optimization
3.9.1.1 Scan size
3.9.1.2 Scan rate
3.9.1.3 Setpoint
3.9.1.4 Integral gain
3.9.1.5 Proportional gain
3.9.2 Offline optimization
3.9.2.1 Planefit
3.9.2.2 Flatten
3.9.2.3 Erase scan line
3.10 Data analysis
3.10.1 Typical image artifacts
3.10.1.1 Artifacts caused by tip–sample convolution
3.10.1.2 Artifacts caused by the contaminated tip
3.10.1.3 Artifacts caused by the scanner
3.10.1.4 Artifacts caused by optical interference
3.10.1.5 Artifacts caused by high-frequency operation
3.10.1.6 Artifacts caused by friction
3.10.1.7 Artifacts caused by inappropriate imaging parameters
3.10.1.8 Artifacts caused by electronic noise
3.10.1.9 Artifacts caused by vibration
3.10.2 Image analysis
3.10.2.1 Section
3.10.2.2 Roughness
3.10.2.3 Bearing
3.11 Conclusion
Acknowledgments
Conflict of interest
References
3 Application of AFM for food research
4 Application of atomic force microscopy for food proteins
4.1 Introduction
4.2 Food protein extraction and sample preparation
4.2.1 Food protein extraction
4.2.2 Sample preparation
4.3 Grain proteins
4.3.1 Rice proteins
4.3.2 Wheat proteins
4.3.3 Maize proteins
4.3.4 Sorghum proteins
4.4 Bean proteins
4.4.1 Soy proteins
4.4.2 Pea proteins
4.5 Peanut proteins
4.6 Milk proteins
4.6.1 Caseins
4.6.2 Whey proteins
4.7 Meat proteins
4.8 Seafood proteins
4.9 Collagen and gelatin
4.9.1 Collagen
4.9.2 Gelatin
4.10 Egg proteins
4.11 Summary and outlook
Acknowledgment
Conflict of interest
References
5 Application of atomic force microscopy for food polysaccharides
5.1 Introduction
5.2 Plant polysaccharide
5.2.1 Starch
5.2.1.1 Analysis of morphology and structure properties of starch
5.2.1.2 Atomic force microscopy study of starch films
5.2.2 Pectin
5.2.2.1 Analysis of pectin degradation during cell wall disassembly
5.2.2.2 Nanostructural analysis of pectin
5.2.3 Cellulose
5.2.4 Others
5.3 Measurement of molecule interactions of polysaccharides and food components
5.3.1 Polysaccharides-polysaccharides
5.3.2 Polysaccharides-protein
5.4 Conclusions
Acknowledgment
Declaration of competing interest
References
Further reading
6 Application of atomic force microscopy in food microorganism research
6.1 Introduction
6.2 Single microbial cell studies
6.2.1 Morphological change evaluation
6.2.2 Antimicrobial mechanism evaluation
6.3 Microbial biofilm studies
6.3.1 Biofilm morphological imaging
6.3.2 Biofilm adhesive property study
6.3.3 Biofilm dynamic process study
6.4 Microbial macromolecule studies
6.4.1 Surface layer protein study
6.4.2 Surface molecular interaction study
6.5 Representatively reported atomic force microscopy studies about different types of microorganisms
6.5.1 Prokaryotic microorganisms
6.5.2 Eukaryotic microorganisms
6.5.3 Viruses
6.6 Combined use of atomic force microscopy with other techniques
6.6.1 Atomic force microscopy and infrared combination
6.6.2 Atomic force microscopy and Raman spectroscopy combination
6.7 Conclusion and future trends
Acknowledgements
Declaration of competing interest
References
7 Application of atomic force microscopy for food foams and emulsions
7.1 Introduction
7.2 Atomic force microscopy applied to food foams and emulsions: fundamentals, operating modes, imaging for topography and ...
7.2.1 Fundamentals of atomic force microscopy: investigation of surfaces
7.2.2 Atomic force microscope
7.2.3 Operating modes for imaging
7.2.4 Force–distance curves for determining surface material properties
7.2.5 Probing air bubbles, lipid droplets, and interfaces
7.3 Application of atomic force microscopy for food foams
7.3.1 Components involved in the air/water interface
7.3.2 Components adsorbed at planar Langmuir films
7.3.3 Air bubbles under the atomic force microscope
7.4 Application of atomic force microscopy for food emulsions and nanoemulsions
7.4.1 Morphology of components used to stabilize oil-in-water emulsions
7.4.1.1 Example 1: applications of atomic force microscopy to pectins
7.4.1.2 Example 2: applications of atomic force microscopy to protein/polysaccharide complexes
7.4.1.3 Example 3: applications of atomic force microscopy to protein fibrils
7.4.1.4 Example 4: applications of atomic force microscopy to protein nanostructures
7.4.1.5 Example 5: applications of atomic force microscopy to cellulose nanocrystals
7.4.2 Morphology of components adsorbed at planar Langmuir films
7.4.2.1 Example 1: applications of atomic force microscopy to cellulose nanoparticles adsorbed at planar Langmuir films
7.4.2.2 Example 2: applications of atomic force microscopy to whey protein-based systems adsorbed at planar Langmuir films
7.4.2.3 Example 3: applications of atomic force microscopy to natural lipid droplets surface such as the egg yolk low-densi...
7.4.3 Nanoemulsions and emulsions: lipid droplets under the atomic force microscopy tip
7.4.3.1 Example 1: applications of atomic force microscopy imaging to air-dried lipid droplets
7.4.3.2 Example 2: application of atomic force microscopy force spectroscopy to plant oil bodies in water
7.5 Application of atomic force microscopy to dairy lipid systems: membranes, liposomes, and emulsions
7.5.1 Milk: from natural to processed oil-in-water emulsions
7.5.2 Topography of lipid monolayers and membranes in air
7.5.3 Topography and mechanical properties of hydrated lipid bilayers
7.5.3.1 Supported lipid bilayers
7.5.3.2 Unsupported lipid bilayers: liposome membranes
7.5.4 Surface topography and roughness of milk fat globules
7.5.5 Probing specific interactions and adhesion forces involved at the surface of milk fat globules
7.5.5.1 Specific interactions: single molecule force spectroscopy
7.5.5.2 Adhesion forces
7.6 Conclusions
Acknowledgments
References
8 Application of atomic force microscopy for food powders and contact materials
8.1 Introduction
8.2 Atomic force microscopy: a powerful tool during formulation and processing of food powders
8.2.1 Carbohydrate-based powders
8.2.1.1 Polysaccharide-based powders
8.2.1.1.1 Formulation
8.2.1.1.2 Processing
8.2.1.2 Disaccharide powders
8.2.1.2.1 Formulation
8.2.1.2.2 Processing
8.2.2 Fat-based powders
8.2.3 Proteins powders
8.3 A better understanding and control of powder functional properties with atomic force microscopy
8.3.1 Reconstitution ability of food powders
8.3.1.1 Powder wetting
8.3.1.2 Powder dispersion
8.3.2 Powder caking
8.3.3 Powder cohesion and flowability
8.3.4 Food powders as a vehicle of bioactive molecules
8.4 Contact materials related to food
8.4.1 Morphological studies of food material surfaces
8.4.2 Quantitative studies of food material surfaces
8.5 Prospects and advanced atomic force microscopy techniques to characterize food powders
8.6 Conclusion
References
9 Advances in food material nanomechanics by means of atomic force microscopy
9.1 Introduction
9.2 Operation modes in atomic force microscopy
9.3 Proteins stretching
9.4 Suppliers, sample preparation, fixation, and tip selection
9.5 Probe selection
9.6 Approaches in food science research with atomic force microscopy
9.7 Recent research on nanomechanical properties of food materials
9.8 Conclusion
References
10 Current and potential combination of atomic force microscopy with other techniques for food science
10.1 Introduction
10.2 Atomic force microscopy combined with infrared technique for food science
10.2.1 Principle and apparatus
10.2.2 Current atomic force microscopy-infrared applications in food science
10.2.3 Prospect of atomic force microscopy-infrared applications in food science
10.3 Atomic force microscopy combined with Raman technique for food science
10.3.1 Principle and apparatus
10.3.2 Current atomic force microscopy-Raman applications in food science
10.3.3 Prospect of atomic force microscopy-Raman applications in food science
10.4 Other atomic force microscopy-combined techniques and their potential applications in food science
10.4.1 Atomic force microscopy combined with mass spectrometry
10.4.2 Atomic force microscopy combined with optical microscopy
10.4.3 Atomic force microscopy combined with X-ray techniques
10.4.4 Atomic force microscopy combined with nanodynamic mechanical analysis
10.4.5 Atomic force microscopy combined with nuclear magnetic resonance
10.4.6 Atomic force microscopy combined with force-loading stage
10.4.7 Atomic force microscopy combined with fluidic force microscopy
10.4.8 Atomic force microscopy combined with optical tweezer
10.5 Summary
References
Index
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