Buyer protection
Donkey milk research · Study 179
Calcium in donkey milk: linked to inhibition of E. coli in the lab
In a laboratory experiment, raw donkey milk samples with a higher calcium content inhibited the growth of E. coli more strongly. Calcium content ranged from 377.1 to 1,231 mg/l; according to the authors, adding calcium chloride and the calcium-binding agent EDTA supported the link.
At a glance · tap the cards
The key figures
Study design
How it was studied
Laboratory study published in European Food Research and Technology. Raw donkey milk was artificially contaminated with E. coli strains and incubated at 38 °C, without additives and with added calcium chloride (CaCl₂, a calcium source) or EDTA (binds calcium ions). Calcium, lysozyme, lactoferrin and pH were determined in all samples. Evaluated based on the abstract: it does not give the number of samples or animals, the number of E. coli strains, bacterial counts or statistical values.
Results
What the study measured
The donkey milk samples inhibited the E. coli strains tested to varying degrees.
Samples with a higher calcium content showed stronger inhibition of the bacteria.
According to the authors, adding calcium chloride and EDTA confirmed that inhibition depended on calcium.
Calcium content ranged from 377.1 to 1,231 mg/l, lysozyme from 0.98 to 3.74 g/l.
Lactoferrin ranged from 2.2 to 54.3 mg/l and was not detectable in 5 samples. pH ranged from 7.11 to 7.25.
Authors’ conclusion: In the trial, the inhibition of E. coli by raw donkey milk depended on its calcium content. What the study does not show: that drinking donkey milk protects against bacteria, or that raw milk keeps itself free of germs.
Critical appraisal
Strengths and limitations
Laboratory test, not humansClear limitation
Milk was mixed with bacteria in a test tube. This cannot be transferred to digestion or infections in humans.
Only the abstract assessedNote
Sample numbers, number of strains, bacterial counts and statistics were not available.
Several factors at onceNote
Lysozyme and lactoferrin also varied widely. The abstract does not allow their contribution to inhibition to be separated.
Origin not statedNote
The abstract does not give the breed, herd or stage of lactation of the animals.
Targeted counter-testStrength
Calcium was deliberately added and bound with EDTA. This supports the observed link beyond a mere correlation.
Editorial note: The paper shows that components such as calcium, lysozyme and lactoferrin can vary widely between individual donkey milk samples. It describes how the milk behaves in the lab, not an effect in humans. To the research archive.
Research question for DON DONKEY’S®
How much do calcium, lysozyme and lactoferrin levels vary between individual batches of our donkey milk, measured over one season?
Original publication
Role of calcium content in antibacterial activity of donkeys’ milk toward E. coli
Original title: Role of calcium content in antibacterial activity of donkeys’ milk toward E. coli
Šarić L. Ć., Šarić B. M., Mandić A. I., Kevrešan Ž. S., Ikonić B. B., Kravić S. Ž., Jambrec D. J.
European Food Research and Technology · 2014 · 239(6), 1031–1039
Institute of Food Technology, University of Novi Sad, Serbia (according to author profiles; not stated in the database record)
DOI: 10.1007/s00217-014-2299-4
Transparency: funding and conflicts of interest could not be checked from the abstract. No product-related statement for DON DONKEY’S®.
Summarised and checked by the DON DONKEY’S editorial team against the original publication · As of: November 2026
The study summarised above was carried out independently of DON DONKEY’S® and does not relate to our products. It serves solely to inform about the state of research.
DON DONKEY’S® donkey milk and donkey milk powder are foods. They are not intended to prevent, treat or cure any disease and do not replace medical advice.
From our shop
DON DONKEY’S® donkey milk
100 % donkey milk · raw milk, frozen
On this page we report the findings of a published study. Independently of that, you will find our donkey milk here: 100 % donkey milk, frozen as raw milk.
100 ml bottle / 100ml · Unit price: €249,00 / 1 l · incl. VAT, plus shipping
Also in our shop
Donkey Milk Powder
Donkey milk in powder form
For anyone who prefers a longer shelf life: our donkey milk in powder form – easy to store and portion.
20g · Unit price: €1.245,00 / 1 kg · incl. VAT, plus shipping