A review on the challenges and opportunities of processing camel milk into dairy products is provided with an objective of exploring the challenges of processing and assessing the opportunities for developing functional products from camel milk. The gross composition of camel milk is similar to bovine milk. Nonetheless, the relative composition, distribution, and the molecular structure of the milk components are reported to be different. Consequently, manufacturing of camel dairy products such as cheese, yoghurt, or butter using the same technology as for dairy products from bovine milk can result in processing difficulties and products of inferior quality. However, scientific evidence points to the possibility of transforming camel milk into products by optimization of the processing parameters. Additionally, camel milk has traditionally been used for its medicinal values and recent scientific studies confirm that it is a rich source of bioactive, antimicrobial, and antioxidant substances. The current literature concerning product design and functional potential of camel milk is fragmented in terms of time, place, and depth of the research. Therefore, it is essential to understand the fundamental features of camel milk and initiate detailed multidisciplinary research to fully explore and utilize its functional and technological properties.
In many countries, especially the dry zones of Sub-Saharan Africa, camels
Camel milk is composed of lactose, fat, and protein in roughly the same proportion as bovine milk (Table
Proximate composition of camel milk compared to milk of other species.
Species | Total solids (%) | Fat (%) | Protein (%) | Lactose (%) | Ash (%) |
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12.0 | 3.5 | 3.1 | 4.4 | 0.8 |
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12.7 | 3.7 | 3.4 | 4.8 | 0.7 |
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12.3 | 4.5 | 2.9 | 4.1 | 0.8 |
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19.3 | 7.4 | 4.5 | 4.8 | 1.0 |
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12.2 | 3.8 | 1.0 | 7.0 | 0.2 |
It is commonly claimed that camel milk is difficult to process into products and is only suitable for drinking as fresh or sour milk. But, currently, the possibility of producing various products from camel milk including soft cheese [
The mean gross chemical composition of camel milk is 3.5% fat, 3.1% protein, 4.4% lactose, 0.8% ash, and 12% total solids, which is comparable to bovine milk (Table
Casein protein distribution of camel, bovine, and human milk.
Caseins (% of total caseins) | Amino acid residues | |||||
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Camel | Bovine | Human | Camel | Bovine | Human | |
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Total caseins (g/100 ml milk) |
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Whey protein distribution of camel, bovine, and human milk.
Whey proteins (g/L) in milk | Amino acid residues | |||||
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Camel | Bovine | Human | Camel | Bovine | Human | |
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Serum albumin |
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— |
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Whey acidic protein |
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— | — |
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Lactoferrin |
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Immunoglobulins |
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— | — | — |
Total whey protein |
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Fatty acid profile of camel milk compared to bovine and human milk (% fatty acid).
Carbon number | Fatty acid | Camel |
Bovine |
Human |
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4:0 | Butyric (%) | 0.8 | 1.4 | 0.1 |
6:0 | Caproic (%) | 0.4 | 2.1 | 0.2 |
8:0 | Caprylic (%) | 0.3 | 1.7 | 0.3 |
10:0 | Capric (%) | 0.4 | 3.5 | 2.0 |
12:0 | Lauric (%) | 0.7 | 3.9 | 6.8 |
14:0 | Myristic (%) | 11.0 | 12.6 | 10.4 |
16:0 | Palmitic (%) | 29.1 | 29.5 | 28.1 |
18:0 | Stearic (%) | 12.4 | 13.3 | 6.9 |
Monounsaturated | ||||
14:1 | 0.5 | — | — | |
16:1 | Palmitoleic (%) | 10.1 | 1.7 | 3.5 |
18:1 | Oleic (%) | 24.5 | 26.3 | 33.6 |
Polyunsaturated | ||||
18:2 | Linoleic (%) | 3.1 | 2.9 | 6.4 |
18:3 | Linolenic (%) | 1.4 | 1.1 | 1.7 |
Unsaturated/saturated | 0.7 | 0.47 | 0.82 | |
Short chain (C4–C14) | 14.6 | 25.2 | 19.8 | |
Long chain (C16–C20) | 84.5 | 72.18 | 80.2 |
Processing camel milk into cheese is difficult and has even been considered as impossible [
Alpha-lactalbumin (
The fat content of camel milk ranges from 1.2 to 6.4% [
However, butter can be made from camel milk under optimum conditions of churning temperature and agitation method. Berhe et al. [
Manufacturing of yoghurt or other fermented products from camel milk is reported to be difficult. Dromedary milk coagulum does not have a desirable curd formation and firmness and the curd is instead fragile and heterogeneous and consists of dispersed flakes [
Nevertheless, there are reports that indicate the possibility of yoghurt production from camel milk [
The unique characteristics of camel milk such as its therapeutic potential and absence
Camel milk has high vitamin C and high mineral contents (sodium, potassium, iron, copper, zinc, and magnesium) and can be good nutritional source for the people living in the arid zones [
Camel milk has been indicated as safe and efficient in improving long-term glycemic control with a significant reduction in the doses of insulin in type 1 diabetic patients [
Camel milk was reported to have an antimicrobial effect against Gram-positive and Gram-negative bacteria including
Camel milk is reported to have antiviral properties. Immunoglobulin and lactoferrin isolated from camel milk could inhibit the hepatitis C virus and demonstrated strong signal against its synthetic peptides, while human counterpart failed to do so [
Bioactive peptides derived from milk proteins are of great scientific interests due to their nutritional, technological, and potential health benefits. Bioactive peptides can be enriched or released from milk proteins by the use of selected starter cultures and enzymes and by manipulation of the manufacturing processes such as nanofiltration and encapsulation [
Camel milk is reported to be a rich source of proteins with potential antimicrobial, angiotensin-converting enzyme (ACE) inhibitory, and antioxidative activities [
Infants who are allergic to bovine milk proteins suffer a severe immune response when they ingest nonhuman milk and thus many studies have been done to reduce the allergenicity of bovine milk or to find milks that can substitute bovine milk without producing an allergenic response [
Amino acid composition of camel milk proteins compared with bovine and human milk proteins (g/100 g protein).
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Arginine | 4.0 | 3.7 | 3.3 |
Histidine | 2.7 | 3.3 | 2.8 |
Isoleucine | 5.1 | 4.9 | 3.7 |
Leucine | 9.7 | 9.3 | 9.5 |
Lysine | 7.2 | 8.1 | 10.1 |
Methionine | 3.2 | 2.5 | 1.7 |
Phenylalanine | 5.0 | 4.2 | 3.9 |
Threonine | 5.7 | 7.3 | 8.3 |
Tryptophan | 1.2 | 1.4 | 0.5 |
Valine | 6.7 | 7.6 | 8.2 |
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Alanine | 3.0 | 4.0 | 4.2 |
Aspartic | 7.0 | 7.0 | 6.7 |
Cysteine | 1.2 | 0.9 | 1.0 |
Glycine | 1.5 | 2.5 | 2.1 |
Glutamic | 21.7 | 18.6 | 16.8 |
Proline | 12.0 | 9.9 | 10.6 |
Serine | 5.2 | 6.2 | 4.1 |
Tyrosine | 4.6 | 4.6 | 2.9 |
Fermented milk products are probably developed from the need to extend the shelf life of milk in the absence of cooling facility, their high nutrient contents, and potential health benefits. Traditionally fermented camel milk is the commonly available camel dairy product unlike camel milk cheese, butter, and yoghurt. Fermented camel milk has different names in different parts of the world;
The main reason for the difficulty of producing products from camel milk is due to the unique structural and functional properties of the milk components. Hence, manufacturing of traditional dairy products using the same technology as for dairy products from bovine milk resulted in processing difficulties. Compositional analyses showed that camel milk is similar to human milk. This indicates the potential of using camel milk in infant formulations to alleviate bovine milk allergy in children. The rich source of bioactive components of camel milk and its compositional properties could be attributed to the therapeutic potential of the milk. Information about the processing technologies and functional properties of camel milk is limited. Hence, more detailed study and holistic approach are needed to fully utilize its technological and functional potentials.
The authors declare that there are no conflicts of interest regarding the publication of this article.
The authors want to express their great thanks to Danish International Development Agency (Danida) for funding “Haramaya Camel Dairy Project.” The partners of the project are the Technical University of Denmark, University of Copenhagen (Denmark), Chr. Hansen A/S (Denmark), and Haramaya University (Ethiopia).