Inhoud
Characteristics & Fermentability of Dietary Fibre – Henk Schols............................................................ 2
1. Overview and upper GI system - ................................................................................................. 2
2. Carbohydrates – Structure and occurrence - 04-01-2021........................................................... 6
3. Dietary fibres – Functionality and fermentation - 05-01-2021 ................................................... 9
4. Dietary fibres – Fermentation models and infant fermentation - 06-01-2021 ......................... 15
Microorganisms, metabolites & gut health – Hauke Smidt .................................................................. 20
5. Gut Microbiota -Why & Where? - 05-01-2021.......................................................................... 20
6. Gut microbiota – How to analyse them - 07-01-2021 ............................................................... 23
7. Gut microbiota – Gut Health - 12-01-2021 ............................................................................... 26
Diet, gut & health: beyond dietary fibre – Eduardo Capuano .............................................................. 27
8. Gut microbiota - Diet and health beyond dietary fibre: phytochemicals 11-01-2021 .............. 27
9. Gut microbiota - Diet and health beyond dietary fibre: proteins and lipids – 14-01-2021 ...... 32
Structural and functional features of the colon – Wilma Steegenga .................................................... 38
1. Macroscopic structures of the colon (humans) ........................................................................ 38
2. Macroscopic structures of the colon (other humans) ............................................................... 39
3. Functions of the colon ............................................................................................................... 40
4. Colon pathologies ...................................................................................................................... 42
5. Methods to examine colonic health .......................................................................................... 43
6. The 4 tissue layer of the colon wall ........................................................................................... 44
7. Three cell types sealed together by tight junctions .................................................................. 45
8. Enteroendocrine cells ................................................................................................................ 46
9. Goblet cells ................................................................................................................................ 47
10. The four components of the intestinal barrier...................................................................... 48
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,Introduction 04-01-2020
• The intestinal tract is a biochemical machinery.
• The course: Food (proteins, fats, carbohydrates, phenolics), Organ:
(mouth, oesophagus, stomach, small intestine, large intestine) and
system (in vivo, human or animal, in vitro).
• Food and food components affect fermentation behaviour, metabolic
product formation and colon barrier function.
• Fermentation strongly depends on indigestible food components and microbiota
composition and activity
• A wide range of metabolites formed during fermentation will be absorbed or will influence
barrier function of the gut and affect human health.
• Discussion during this course: Animal, human in vitro studies. The effect and process of
fermentation. The influence of prebiotics, probiotics and dietary fibre.
Characteristics & Fermentability of Dietary Fibre – Henk Schols
1. Overview and upper GI system - 04-01-2021
• Fate of digestible food components:
- Mechanical breakdown
- Biochemical breakdown
- Absorption
• Fate of indigestible food components – yet to come.
• Our daily food intake: Healthy diet.
• Nutrient composition → Digestion and absorption of nutrients → post
absorptive utilization of nutrients → Nutrients.
• Human digestion system, pH. is off upmost essence →
• In animals: Fermentation may start already in the caecum (beginning part
of the large intestine). In humans the fermentation occurs in the large
intestine.
• Lipid digestion: Mostly tri-acyl-glycerol
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,• The pH. in the stomach is fluctuating constantly, when eaten a heavy meal the pH. will go up,
but when you have eaten nothing for a long time it will be low.
• Fat digestion and absorption in the small intestine:
• Protein digestion: Upper GI system
• Protein digestion and absorption in small intestine
• Carbohydrate digestion in the upper GI system:
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, • Carbohydrate digestion and absorption:
• Factors affecting macronutrient digestion:
- ‘Intrinsic’ factor: variation in chemical structure
- Food texture (gel, particle, emulsion, foam, ...), Water Holding Capacity (DF),
- Processing: Lipid: emulsification, Protein: structure, Carbohydrate: starch
gelatinisation/retrogradation(in)solubility of dietary fibre
- Interaction with other components in food E.g., starch-protein, starch-lipid and
phenolics-protein interaction
- Inhibition of digestive enzymes by food components. Example: alginate inhibits
lipase1and protease2
- Disorders (genetic defect, health problems, etc)
• Summary digestion in Upper GI tract
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