Introduction lecture (9/1/2023)
● The intestinal tract is a (bio)chemical
machinery.
● Foods are composed of:
○ Proteins.
○ Fat.
○ Carbohydrates.
○ Phenolics.
● Organs involved in the gastrointestinal
tract are:
○ Mouth.
○ Esophagus.
○ Stomach.
○ Small intestine.
○ Large intestine.
● Systems involved in the gastrointestinal
tract are:
○ In vivo.
■ In the human or animal body.
○ In vitro.
● Food and food components affect fermentation behavior, 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 the barrier function of the gut and will affect human health.
● In week 1 there will be 4 afternoons that consist of a Q&A and experiments. All
groups will start on Tuesday at 14.00h.
● In week 1 & 2 there will be 5-6 afternoons for result evaluation and report writing.
● In week 2 & 3 the second practical classes start. This is an online module. There is a
deadline.
● In week 3 there will be 4 tutorials. Attendance is not compulsory, but is
recommended. Exam questions will be asked during the tutorials.
Practicals:
● 4 members per group. These same 4 people will also work together on the case.
● Each member will first work independently. Interaction between members is
stimulated.
● In the first afternoon, a fermentation process will start. Results of various analyses
become available throughout the first three days.
● For the fermentation, each student will have a combination of one fiber and one
inoculum.
● Try to answer the questions in the manual before starting the evaluation of the
results.
● Every day, a short discussion of the questions will be organized by the supervisor.
, ● A joint report per group will allow you to understand the basic rules of fermentation.
Case study:
● Introduction: 18-01-2023.
● You have to design a food product for a specific target group.
● 19 + 20 January → idea pitch.
● 27 January → final presentation. All groups should be present.
● Presentation + PPT speaker notes + idea pitch = mark.
● The final exam will count for 70% of the final mark.
● The lab practical will count for 15% of the final mark.
● The case study will count for 15% of the final mark.
● For all parts, a minimum mark of 5.5 is required in order to obtain a final mark.
, Lecture 1 (9/1/2023): Overview upper digestive tract
● Digestible food components are subject to different
processes in the upper digestive tract:
○ Mechanical breakdown.
○ (Bio)chemical breakdown.
■ pH.
■ Enzymes.
○ Absorption.
● You end up with the indigestible food components.
● Foods are fermented in the colon.
● One should consume a healthy diet, which has a certain
nutrient composition.
○ There are daily dietary intakes for nutrients.
○ In an unhealthy diet, one does not feed the
microbiota sufficiently.
● Digestion and absorption of the nutrients takes place.
● Thereafter, there is post absorptive utilization of nutrients.
○ Nutritional value.
- PRI: Population Reference Intake. This is the level of nutrient
intake that is adequate for virtually all people in a population
group.
● Proteins, fats and carbohydrates are all macronutrients.
● The dietary daily intake differs for different age groups.
● Different enzymes are involved in the human digestive system.
● Mouth (pH 6-7):
○ Saliva.
■ Lingual lipase.
■ α-amylase.
● Stomach (pH 2-3):
○ Gastric liquid.
■ Pepsin.
● Small intestine (pH 6-7.5):
○ Pancreatic mixture.
■ Proteases.
■ Lipase.
■ α-amylase.
○ Biliary mixture.
■ Bile salts.
■ Bilirubin phospholipid.
● Large intestine (pH 6.5-7.5):
○ Bacteria.
, ● In animals, fermentation may start already in the caecum (end of the small intestine).
● Lipids found in the human diet
are mainly tri-acyl-glycerols
(TAG/triglycerides).
● In the upper GI system, lipid
digestion (hydrolysis) takes
place.
● ~15% of the lipids is hydrolyzed
after passing the stomach.
● In the small intestine
(duodenum, jejunum, ileum)
there is a very high hydrolysis
efficiency and absorption
(>90%).
● The enzymes involved in lipid hydrolysis are lingual lipase, gastric lipase, bile
(emulsification) and pancreatic lipases.
● The gallbladder produces bile
salts, which emulsify the large
triglyceride droplets into emulsion
droplets.
● Pancreatic lipase hydrolyses the
emulsion droplets into
monoglycerides and free fatty
acids.
○ These can be absorbed
through the brush border.
● There are ~20 amino acids in the human
diet.
○ Amino acids are connected through
a peptide bond.
● Primary structure → sequence of a chain of
amino acids.
● Secondary structure → local folding of the polypeptide chain into α-helices or
β-pleated sheets.
● Tertiary structure → 3D folding pattern of a protein due to side chain interactions.
● Quaternary protein structure → protein consisting of more than one amino acid chain.
● In the upper GI system, protein digestion (hydrolysis) takes place.
● The intestinal tract is a (bio)chemical
machinery.
● Foods are composed of:
○ Proteins.
○ Fat.
○ Carbohydrates.
○ Phenolics.
● Organs involved in the gastrointestinal
tract are:
○ Mouth.
○ Esophagus.
○ Stomach.
○ Small intestine.
○ Large intestine.
● Systems involved in the gastrointestinal
tract are:
○ In vivo.
■ In the human or animal body.
○ In vitro.
● Food and food components affect fermentation behavior, 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 the barrier function of the gut and will affect human health.
● In week 1 there will be 4 afternoons that consist of a Q&A and experiments. All
groups will start on Tuesday at 14.00h.
● In week 1 & 2 there will be 5-6 afternoons for result evaluation and report writing.
● In week 2 & 3 the second practical classes start. This is an online module. There is a
deadline.
● In week 3 there will be 4 tutorials. Attendance is not compulsory, but is
recommended. Exam questions will be asked during the tutorials.
Practicals:
● 4 members per group. These same 4 people will also work together on the case.
● Each member will first work independently. Interaction between members is
stimulated.
● In the first afternoon, a fermentation process will start. Results of various analyses
become available throughout the first three days.
● For the fermentation, each student will have a combination of one fiber and one
inoculum.
● Try to answer the questions in the manual before starting the evaluation of the
results.
● Every day, a short discussion of the questions will be organized by the supervisor.
, ● A joint report per group will allow you to understand the basic rules of fermentation.
Case study:
● Introduction: 18-01-2023.
● You have to design a food product for a specific target group.
● 19 + 20 January → idea pitch.
● 27 January → final presentation. All groups should be present.
● Presentation + PPT speaker notes + idea pitch = mark.
● The final exam will count for 70% of the final mark.
● The lab practical will count for 15% of the final mark.
● The case study will count for 15% of the final mark.
● For all parts, a minimum mark of 5.5 is required in order to obtain a final mark.
, Lecture 1 (9/1/2023): Overview upper digestive tract
● Digestible food components are subject to different
processes in the upper digestive tract:
○ Mechanical breakdown.
○ (Bio)chemical breakdown.
■ pH.
■ Enzymes.
○ Absorption.
● You end up with the indigestible food components.
● Foods are fermented in the colon.
● One should consume a healthy diet, which has a certain
nutrient composition.
○ There are daily dietary intakes for nutrients.
○ In an unhealthy diet, one does not feed the
microbiota sufficiently.
● Digestion and absorption of the nutrients takes place.
● Thereafter, there is post absorptive utilization of nutrients.
○ Nutritional value.
- PRI: Population Reference Intake. This is the level of nutrient
intake that is adequate for virtually all people in a population
group.
● Proteins, fats and carbohydrates are all macronutrients.
● The dietary daily intake differs for different age groups.
● Different enzymes are involved in the human digestive system.
● Mouth (pH 6-7):
○ Saliva.
■ Lingual lipase.
■ α-amylase.
● Stomach (pH 2-3):
○ Gastric liquid.
■ Pepsin.
● Small intestine (pH 6-7.5):
○ Pancreatic mixture.
■ Proteases.
■ Lipase.
■ α-amylase.
○ Biliary mixture.
■ Bile salts.
■ Bilirubin phospholipid.
● Large intestine (pH 6.5-7.5):
○ Bacteria.
, ● In animals, fermentation may start already in the caecum (end of the small intestine).
● Lipids found in the human diet
are mainly tri-acyl-glycerols
(TAG/triglycerides).
● In the upper GI system, lipid
digestion (hydrolysis) takes
place.
● ~15% of the lipids is hydrolyzed
after passing the stomach.
● In the small intestine
(duodenum, jejunum, ileum)
there is a very high hydrolysis
efficiency and absorption
(>90%).
● The enzymes involved in lipid hydrolysis are lingual lipase, gastric lipase, bile
(emulsification) and pancreatic lipases.
● The gallbladder produces bile
salts, which emulsify the large
triglyceride droplets into emulsion
droplets.
● Pancreatic lipase hydrolyses the
emulsion droplets into
monoglycerides and free fatty
acids.
○ These can be absorbed
through the brush border.
● There are ~20 amino acids in the human
diet.
○ Amino acids are connected through
a peptide bond.
● Primary structure → sequence of a chain of
amino acids.
● Secondary structure → local folding of the polypeptide chain into α-helices or
β-pleated sheets.
● Tertiary structure → 3D folding pattern of a protein due to side chain interactions.
● Quaternary protein structure → protein consisting of more than one amino acid chain.
● In the upper GI system, protein digestion (hydrolysis) takes place.
