Buyer protection
Contents
Serbian cow's milk cheese with 30% donkey milk: Coagulation took 2 hours instead of 30 minutes, the yield fell from 1.37 to 1.10 kg, the protein content rose from 13.45 to 15.75%.
Laboratory analysis – no statement about an effect in humans. Donkey milk is a food.
Study profile
| Feature | Information |
|---|---|
| Original title | Incorporating Pooled Donkey Milk from Autochthonous Balkan and Banat Donkey Breeds into Traditional Dairy Products: Effects on Technological Properties, Nutritional Profile, and Sensory Acceptability of Podliveni Cheese |
| Authors | Ljubojević Pelić D., Vidaković Knežević S., Popov N. et al. |
| Journal | Animals, Volume 16, Issue 10, Article 1449 |
| Year | 2026 |
| Country | Serbia |
| Study type | Laboratory study |
| DOI | 10.3390/ani16101449 |
How it was investigated
Two batches of traditional Serbian Podliveni cheese were made in a small dairy: one from raw cow's milk, one from 7 L of raw cow's milk and 3 L of raw donkey milk (30%). The donkey milk came as pooled milk from Balkan and Banat donkeys from the Zasavica Nature Reserve (morning milking, December 2024). Except for the coagulation time, the manufacturing process was identical (40 °C, rennet, draining for 12 hours, dry salting by hand). Among other things, the chemical composition, minerals (ICP-MS) and acceptance by a panel of 21 people on a five-point scale were investigated; each group had one cheese sample with triplicate determination.
The most important figures
| Value | Meaning |
|---|---|
| 30% | Donkey milk content (3 L donkey milk to 7 L cow's milk) |
| 30 min vs. 2 h | Coagulation time: pure cow's milk vs. mixture with donkey milk |
| 1.37 vs. 1.10 kg | Cheese yield from 10 L of milk: cow's milk vs. mixture (p < 0.05) |
| 13.45 vs. 15.75% | Protein content in cheese: cow's milk vs. with donkey milk (p < 0.001) |
| 22.00 vs. 20.87% | Fat content in cheese: cow's milk vs. with donkey milk (p = 0.030) |
| 39.82 vs. 40.72% | Dry matter in cheese: cow's milk vs. with donkey milk (p = 0.012) |
| 3577 vs. 3276 mg/kg | Calcium in cheese: cow's milk vs. with donkey milk |
| 694 vs. 506 mg/kg | Potassium in cheese: cow's milk vs. with donkey milk |
The results
With 30% donkey milk, coagulation proceeded significantly slower: 2 hours instead of 30 minutes with pure cow's milk. The yield fell from 1.37 ± 0.05 kg to 1.10 ± 0.09 kg (p < 0.05); the cheese released more whey during storage and was softer.
The cheese with donkey milk contained less fat (20.87 vs. 22.00%) and more protein (15.75 vs. 13.45%) as well as slightly more dry matter (40.72 vs. 39.82%). Ash (1.52 vs. 1.54%) and pH (4.94 vs. 4.86) did not differ significantly.
For the minerals, calcium (3276 vs. 3577 mg/kg), phosphorus, potassium (506 vs. 694 mg/kg), zinc and copper, as well as the Ca/P ratio (1.17 vs. 1.25), were lower; sodium, magnesium (127 vs. 101 mg/kg) and iron (6.74 vs. 5.75 mg/kg) were higher.
In the sensory panel (21 people), only the texture of the cheese with donkey milk was rated significantly worse (2.67 vs. 3.38). Color, aroma, taste and overall impression did not differ significantly, but were consistently slightly lower.
The authors conclude that donkey milk from Balkan and Banat donkeys can be incorporated into traditional Podliveni cheese without significantly changing most sensory characteristics. However, coagulation, yield and texture would need to be technologically optimized.
Critical assessment
- Limitation – Only one batch: Only one cheese was made per group; according to the authors, the triplicate determinations reflect mainly the measurement accuracy, not the variation between production batches.
- Note – Contradictory coagulation time: The abstract and methodology speak of about six times longer coagulation; however, the stated values (30 min vs. 2 h) correspond to four times.
- Note – Salting by hand: According to the authors, the differences in salt and sodium may have arisen from manual salting and should therefore be interpreted with caution. In addition, the stated "fat-free dry matter" (77.13 and 74.91%) is above the dry matter; the term is not further explained in the text.
- Limitation – Pooled raw milk: The donkey milk was a pooled sample from two breeds from a reserve and a month; breed-specific statements are not possible. The milk characteristics come from an earlier study by the same group. Raw milk was processed.
- Note – Small sensory panel: The 21 test persons were employees of the conducting institute; the evaluation was carried out on a simple hedonic scale.
- Strength – Broad analysis: Identical manufacturing process, standardized analysis according to ISO standards, mineral analysis by ICP-MS and complete result tables with p- and F-values.
Funding, conflicts of interest and level of evidence
Funded by the Science Fund of the Republic of Serbia (No. 3535, PROTECTDonkey project for the protection of domestic donkeys in the Zasavica Nature Reserve) as well as by the Serbian Ministry of Science, Technological Development and Innovation (contracts 451-03-33/2026-03/200031 and 451-03-33/2026-03/200222).
The authors state that there are no conflicts of interest.
Level of evidence: Basic research (laboratory) – describes the properties of the milk, no statement about effects in humans.
Our assessment
It is a technological feasibility test with one cheese batch each; the results describe composition and acceptance, no effects in humans.
Open research question: How do yield, texture and acceptance change when the donkey milk content is varied step by step and the coagulation is technologically adjusted?
You can find all measurement values, interactive graphics and the complete critical assessment on our research page: Study 94: Podliveni Cheese with 30% Donkey Milk. Further studies in the research archive.
Ljubojević Pelić D., Vidaković Knežević S., Popov N., Knežević S., Vranešević J., Pelić M., Živkov Baloš M. (2026). Incorporating Pooled Donkey Milk from Autochthonous Balkan and Banat Donkey Breeds into Traditional Dairy Products: Effects on Technological Properties, Nutritional Profile, and Sensory Acceptability of Podliveni Cheese. Animals, Volume 16, Issue 10, Article 1449. DOI: 10.3390/ani16101449
Summarized and checked by the DON DONKEY'S editorial team based on the original publication · As of: October 2026. This summary does not replace the original work.
End of the study summary. The study was conducted independently of DON DONKEY'S® and does not refer to our products. Our donkey milk is a food.
