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Camel Milk Products |  |
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1. Fermented Milk
In pastoral societies, milk is traditionally consumed predominantly in the form of fermented milk. Fermentation is the only means of preserving milk under warm condition. In eastern Africa, however, where 60% of the world camel population are held, there is a long tradition in preparing fermented camel milk camel. The milk is either home-consumed or sold.
To prepare fermented camel milk, containers of calabas, cly potes , plant fibre vessels or hollowed wood vessels are smoked by burning chips of Olea africana or Acacia busia. The daily residual fresh milk is poured into the milk container. No starters are used and acidification develops after e few days, either from natural flora of milk when it is not boiled, or from the bacteria growing on the sides of the vessel.
The milk is left in a quite place, often in a covered container sheltered from dust for usually 24-48 hours until it becomes sour. The ambient temperature is normally between 25 and 35 °C. Due to spontaneous nature of the fermentation, this traditional method results in a product with varying taste and flavor and often of poor hygienic quality.
To improve this spontaneous traditional fermentation, controlled fermentation using mesophilic lactic acid bacteria starter culture have been developed and successfully introduced in camel milk processing plants in different eastern African countries.
Journal of dairy research (1990), 57 281-283 
2. Cheese
Most attempts to make cheese from camel milk have revealed major difficulties in getting the milk to coagulate. With the same amount of calf rennet, the coagulation time of camel milk is two to three-folds longer than in cow milk. The action of rennet on camel milk leads to coagulation in the form of flocks, with no firm coagulation. There are some reports in the literature showing that clotting enzyme from one species is more effective and specific with milk from the same species. Chymosin from lamb where found to be more effective with lamb milk than with cow milk. Pig chymosin and pig pepsin have shown higher milk clotting activity against porcine milk than against bovine milk. These findings suggest an adaptation between the proteolytic specificities of the gastric proteases and the structure of the caseins. Accordingly, it can be expected that camel chymosin would be more effective in camel milk than calf chymosin. Following this, our Laboratory developed recombined camel chymosin, from mRNA, obtained from the stomach of a young camel. The process has been patented.
After the preliminary tests in laboratory showed the effectiveness of the Camel chymosin field studies for making cheese from camel milk have been successfully run in different east African and Sahel countries.
Camel chymosin can be obtained from Dr. Zakaria Farah farah@camelgate.com
3. Butter
Like cheese, butter is also not a traditional camel milk product as is it difficult to obtain camel milk butter following the same preparation procedures as for cow’s milk. This is due to the lack of agglutinin, a protein which promotes clustering of fat globules and formation of cream layer in cold milk. Also the high melting point (41-42C°) of camel milk fat makes difficult churning camel milk cream in temperatures commonly used for churning cow milk.
Our laboratory developed a simple method for manufacturing butter from camel milk fat. According to the method, butter was obtained by churning camel milk cream at temperatures between 20 and 25C°. This temperature is considerably higher than that of cow milk which normally varies between 8 and 12C°.
Milchwissenschaft. (1989)44 (7), 412-414
Milchwissenschaft. (1991)46 (6), 361-362
4. Heat treated product
There are very few studies on the effect of heat treatment on the proteins of camel milk. Research work in our Laboratory indicates that the whey proteins in camel milk are more heat resistant than in cow milk. Under the selected experimental conditions the rate of heat denaturation of camel milk whey proteins was approximately twofold lower than cow milk whey proteins. This indicates that camel milk can be easily pasteurised, and there are commercial small and middle scale camel milk processing plants for production of pasteurised milk in Mauritania, Kenya and Somalia.
Milchwissenschaft (1986) 41(12), 763-765
Journal of Dairy Research (1992) 59 229-231
Ongoing investigation to study the ability of camel milk to withstand ultra-high processing temperatures UHT showed heat instability of camel milk. Bulk camel milk collected from camels in Kenya were UHT heat treated applying both direct (150C°/ 2 sec.) and indirect (138C°/ 8-10 sec.) method. After processing the milk was stored at 5, 10, 25 and 30C°for five weeks. After 3 weeks, milk stored at 25 and 30 °C separated forming fine deposit which was more in milk processed by indirect method then the direct. No deposit formation was observed in milk stored at 5 and 10 °C even after 5 weeks storage. This heat instability of camel milk at high processing temperatures can be due to the low content of K-casein and the total absence of â- Lactoglobulin in camel milk. Both proteins play an important role in the heat stability of bovine milk.
Our conclusion so far is that camel milk can not be UHT treated following the same procedure as in cow milk. UHT methods adapted to camel milk are now under investigation.
More on camel milk products, recipes, processing techniques as well as methods for quality control and equipments for small scale camel milk processing plants are in
“Milk and meat from camel: Hand book on products and processing”
Z. Farah and A. Fischer (Editors) . flyer.pdf
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