A recently published scientific study has made it possible to identify some strains of probiotic lactic bacteria in camel milk, of appreciable value for the health of consumers. (1)
Camel milk, trad-innovation
Camel milk it's a superfoods of great interest, from a nutritional point of view but also for the ability to contribute to the correct functioning of the immune system and to reduction of risk factors of some serious pathologies (eg diabetes). In addition to being an excellent substitute for breast milk. In consideration of this, among other things, the Camel Milk research project was launched, in the program of partnerships europ-Mediterranean FIRST, in which we have the honor to participate. (2)
The study under consideration, conducted in India, made it possible to isolate and select three LAB strains (Lactic acid bacteria) species Lactococcus lactis, Enterococcus lactis e Lactobacillus plantarum, which have been tested to evaluate their prebiotic properties and technological aptitude for the production of fermented products. The isolation was carried out by traditional Indian races (Mewari, Bikaneri, Kachchi and Jaisalmeri), whose names derive from the regions of origin.
Characterization of the samples
Analysis of the samples of milk have confirmed the excellent characteristics of this superfoods. The results, in a nutshell.
- Fat: they mainly consist of polyunsaturated fatty acids (PUFA).
- Proteins: absence of β-lactoglobulin (allergenic whey protein), which favors the replacement of breast milk, high presence of α-lactalbumin and β-casein, useful for the transformation of milk and, above all, of immunoglobulins useful for improving the system immune system and reduction of allergic reactions.
- Vitamins: rich in Vitamin C, which facilitates the lowering of the pH in the gastrointestinal tract and the absorption of nutrients.
- Minerals: rich in Calcium, Iron and Zinc. The latter is also involved in the proper functioning of the immune system.
The species of LAB isolated have been identified first by genus and then by species. Their presence is generally very abundant also in cow and goat milk and the distribution in the population seems to be linked to the environment (both work and stay of the animals), nutrition and milk processing practices. (3)
Functional properties of probiotics
The main features requirements in probiotics, for their optimal function, were analyzed in the isolated LAB strains. Specifically, the following were measured:
- tolerance to acid environments: like that of the stomach. All showed good growth at pH 3, but the E. lactis e L. plantarum they also managed to tolerate pH 2 values, an excellent requirement for probiotics; (4)
- tolerance and hydrolysis of bile salts: important, because otherwise they adhere to the lipid membranes of probiotics, leading to their rupture and death of probiotics (5). E. lactis e L. plantarum they resisted concentrations up to 0.3% and were able to hydrolyze these salts, showing an ability to reduce the accumulation of cholesterol;
- antimicrobial and antitumor activity: all strains have shown the ability to produce substances with antimicrobial action (bacteriocins and organic acids), specific against the growth of pathogenic bacteria and which can also be used as food preservatives. The antitumor action is linked to the ability to adhere and persist on the intestinal epithelium, thanks to which it can compete and prevent the adhesion of tumor cell lines such as Caco-2 or various enteropathogens;
- safety of probiotics: was evaluated through the haemolytic activity of red blood cells and the production of biogenic amines. All strains were found to be free from these activities and were therefore safe.
These results allowed to identify as safe the LAB strains of the three analyzed species and to make them suitable candidates to be used as probiotics and as cultures starter for the production of food, for which it was necessary to evaluate the technological aptitude.
Technological properties of LABs
Curds have been prepared probiotic, evaluated for their organoleptic attributes (eg color, appearance, texture, taste, smell) and compared with a control. The products obtained with the strains of L. lactis e L. plantarum they have improved from this point of view, thanks to the production of aromatic compounds and organic acids which have contributed to the characterization of the fermented products obtained.
During the process, all strains showed a good technological aptitude especially as regards the reduction of syneresis (whey loss). Together with the organoleptic characterization, they have also proved valid as crops starter for the production of excellent fermented milks, characterized by peculiar and original sensory characteristics, favorably acceptable by consumers.
Camel milk and some specific strains of three LAB species have proved to be excellent probiotics, which can also be used in the production of processed foods that have important sensory and even probiotic characteristics, useful for human nutrition and, probably, also for infants. In this way, it is possible to promote the market for this type of product and guarantee better food and economic subsistence in the countries most in need and new opportunities in our markets.
These results support the Camel Milk project, which has almost reached its second year of operation together with World Milk Day, which is celebrated on June 1st. Project to which WIISE Srl, with its FARE division, is working simultaneously with the ProFuture project to promote the production of good, safe, high nutritional and healthy impact foods available for all.
Dario Dongo and Andrea Adelmo Della Penna
(1) Sharma et al. (2021) Identification and probiotic potential of lactic acid bacteria from camel milk. Saudi Journal of Biological Sciences 28: 1622-1632, https://doi.org/10.1016/j.sjbs.2020.11.062
(2) Dario Dongo. Camel Milk, superfood. Mediterranean research project. GIFTS (Great Italian Food Trade) 02.06.2019, https://www.greatitalianfoodtrade.it/progresso/camel-milk-superfood-progetto-di-ricerca-mediterranea
(3) Tormo et al. (2015). Phenotypic and genotypic characterization of lactic acid bacteria isolated from raw goat milk and effect of farming practices on the dominant species of lactic acid bacteria. Int. J. Food Microbiol. 210: 9–15, https://doi.org/10.1016/j.ijfoodmicro.2015.02.002
(4)Das et al. (2016). In Vitro probiotic characterization of Lactobacillus casei isolated from marine samples. LWT - Food Sci. Technol. 73: 383–390, https://doi.org/10.1016/j.lwt.2016.06.029
(5) Choi et al. (2015). Cholesterol-lowering effects of a putative probiotic strain L. plantarum isolated from kimchi. LWT - Food Sci. Technol. 62: 210-217, https://doi.org/10.1016/j.lwt.2015.01.019