Buyer protection
ACE-inhibitory activity
The researchers examined inhibition of angiotensin-converting enzyme (ACE) in the laboratory. Such measurements are often used to characterise bioactive peptides in foods.
DON DONKEY’S® · Research · Study 24
Fermented donkey milk
& digestion
What happens to the bioactive properties of donkey milk when it is fermented and then subjected to simulated gastrointestinal digestion?
Scientific context: The study was carried out under laboratory conditions. Measured bioactivities must not be equated with a proven health effect in humans.
Study 24
01
The research question
Biochemically, milk is far more than a mixture of fat, protein and carbohydrates.
Scientists therefore investigate, among other things, which biologically active components are formed, preserved or changed during processing and digestion.
This study focused on fermented donkey milk. The researchers analysed its bioactive properties before and after simulated gastrointestinal digestion.
They were particularly interested in peptides, ACE-inhibitory activity, antioxidant activity and antimicrobial properties.
Experimental setup
From milk through fermentation
to simulated digestion
The study did not only look at the starting product. The decisive question was how the properties examined change during different processing steps.
1
Donkey milk
The starting point of the study was donkey milk with its natural protein and peptide composition.
2
Fermentation
The milk was fermented with different starter cultures. In the process, milk proteins can be altered and peptides released.
3
Simulated digestion
Gastrointestinal digestion was then simulated under laboratory conditions, and the bioactivities that were measurable were examined again.
What was measured?
Four areas were
particularly in focus
Antioxidant activity
In addition, they tested which antioxidant activity the fermented samples examined showed under the laboratory conditions used.
Antimicrobial activity
Another part of the study dealt with the antimicrobial activity of the fermented products in the experimental system used.
Bioactive peptides
The study also looked at the role of peptides that can be formed or released during fermentation and digestion.
DON DONKEY’S® donkey milk
Our donkey milk is the food whose scientific background we discuss on this research page. However, the product offered here is not the same as the fermented experimental product made in this study.
The interesting point
Digestion does not necessarily mean the end of bioactivity.
In the study, the measured bioactive properties were pronounced in the fermented products. After simulated gastrointestinal digestion, even stronger activities were measured in some cases.
At the same time, the study showed that the result was influenced by which starter strain was used for fermentation.
Fermentation
Proteins are altered
During fermentation, microorganisms can cleave milk proteins enzymatically. This can produce smaller protein fragments or peptides.
Digestion
Further peptides can form
Digestive enzymes also break down proteins. Simulated digestion can therefore further change the composition of the peptides present.
Result
Bioactivity remained measurable
Above all, the study shows that certain activities measurable in the laboratory can still be present after fermentation and simulated digestion.
Placing it correctly in scientific context
What the study shows –
and what it does not
What was observed
✓ Fermented donkey milk showed measurable bioactive properties in the laboratory.
✓ ACE-inhibitory, antioxidant and antimicrobial activity were among the properties examined.
✓ After simulated gastrointestinal digestion, bioactivities were still measured or measured more strongly.
✓ The choice of starter strain influenced the properties examined.
What is not proven by this
× The study does not prove a blood pressure-lowering effect of donkey milk in humans.
× ACE inhibition in a laboratory test is not equivalent to a clinical effect in the human body.
× Antioxidant or antimicrobial laboratory activity does not demonstrate treatment or prevention of any disease.
× The fermented donkey milk examined is not identical to the fresh donkey milk we offer.
“
The study provides indications that fermentation and digestion do not simply make the bioactive properties of donkey milk disappear but can change their measurable activity and peptide composition.
This is a result from an experimental in vitro system. Whether and to what extent physiological effects in humans result from it cannot be answered by this study.
DON DONKEY’S®
DON DONKEY’S® donkey milk
100 % donkey milk · directly from the donkey farm
Discover our donkey milk and learn more on our research pages about why donkey milk has for years been the subject of scientific research on proteins, peptides and other milk components.
Important: The study presented on this page examined fermented donkey milk under laboratory conditions. The product offered here is not the fermented experimental product examined in the study. No specific health effect of our product is therefore derived from the study results.
€24,90
The research content presented is for scientific information only. It does not constitute medical advice and is not a statement that DON DONKEY’S® donkey milk prevents, treats or cures diseases.
Original publication
Bioactive properties of fermented donkey milk, before and after in vitro simulated gastrointestinal digestion
Publication: Food Research International, 2018
PubMed: PMID 30064786
Open original study on PubMed →
Note: The content presented here is a plain-language summary of the scientific study. In vitro results do not allow any direct statement about health effects in humans.