African fermented dairy products – Overview of predominant technologically important microorganisms focusing on African Streptococcus infantarius variants and potential future applications for enhanced food safety and security

International Journal of Food Microbiology

Volumn 250, Issue , 2017, Pages 27-36

  Jans, Christoph ^a   Meile, Leo ^a   Kaindi, Dasel Wambua Mulwa ^b   Kogi Makau, Wambui ^b   Lamuka, Peter ^b   Renault, Pierre ^c   Kreikemeyer, Bernd ^d   Lacroix, Christophe ^a   Hattendorf, Jan ^e,f   Zinsstag, Jakob ^e,f   Schelling, Esther ^e,f   Fokou, Gilbert ^g   Bonfoh, Bassirou ^e,f,g  

^a ETH ZURICH   (Switzerland)

^b UNIVERSITY OF NAIROBI   (Kenya)

^c UNIVERSITÉ PARIS SACLAY   (France)

^d ROSTOCK UNIVERSITY MEDICAL CENTER   (Germany)

^e SWISS TROPICAL AND PUBLIC HEALTH INSTITUTE   (Switzerland)

^f UNIVERSITY OF BASEL   (Switzerland)

^g CENTRE SUISSE DE RECHERCHES SCIENTIFIQUES EN CÔTE D'IVOIRE   (Côte d’Ivoire)

Author keywords

Food fermentation; Lactic acid bacteria; Microbiota; Milk production system; Streptococcus bovis Streptococcus equinus complex; Streptococcus infantarius

Indexed keywords

AFRICA; FERMENTATION; FERMENTED MILK PRODUCT; FOOD QUALITY; FOOD SAFETY; FOOD SECURITY; FUNCTIONAL GENOMICS; HUMAN; LACTIC ACID BACTERIUM; LACTOCOCCUS LACTIS; NONHUMAN; REVIEW; STARTER CULTURE; STREPTOCOCCUS; STREPTOCOCCUS INFANTARIUS; YEAST; ANIMAL; CLASSIFICATION; FOOD CONTROL; LACTOBACILLUS; METABOLISM; MICROBIOLOGY; MICROFLORA; MILK;

AFRICA; ANIMALS; CULTURED MILK PRODUCTS; FERMENTATION; FOOD MICROBIOLOGY; FOOD SAFETY; HUMANS; LACTOBACILLUS; LACTOCOCCUS LACTIS; MICROBIOTA; MILK; STREPTOCOCCUS;

EID: 85016333260     PISSN: 01681605     EISSN: 18793460     Source Type: Journal    
DOI: 10.1016/j.ijfoodmicro.2017.03.012     Document Type: Review

References (91)

1. Abdelgadir, W., Nielsen, D.S., Hamad, S., Jakobsen, M., A traditional Sudanese fermented camel's milk product, Gariss, as a habitat of Streptococcus infantarius subsp. infantarius. Int. J. Food Microbiol. 127 (2008), 215–219.
2. Akabanda, F., Owusu-Kwarteng, J., Tano-Debrah, K., Glover, R.L., Nielsen, D.S., Jespersen, L., Taxonomic and molecular characterization of lactic acid bacteria and yeasts in nunu, a Ghanaian fermented milk product. Food Microbiol. 34 (2013), 277–283.
3. Ayenew, Y.A., Wurzinger, M., Tegegne, A., Zollitsch, W., Performance and limitation of two dairy production systems in the North western Ethiopian highlands. Trop. Anim. Health Prod. 41 (2009), 1143–1150.
4. Bayemi, P.H., Webb, E.C., An integrated method for improving the dairy production sector in developing countries: the case of Cameroon. Trop. Anim. Health Prod. 41 (2009), 525–534.
5. Bechir, M., Schelling, E., Kraemer, K., Schweigert, F., Bonfoh, B., Crump, L., Tanner, M., Zinsstag, J., Retinol assessment among women and children in sahelian mobile pastoralists. EcoHealth 9 (2012), 113–121.
6. Bensalah, F., Delorme, C., Renault, P., Characterisation of thermotolerant cocci from indigenous flora of ‘leben’ in algerian arid area and DNA identification of atypical Lactococcus lactis strains. Curr. Microbiol. 59 (2009), 139–146.
7. Beukes, E.M., Bester, B.H., Mostert, J.F., The microbiology of South African traditional fermented milks. Int. J. Food Microbiol. 63 (2001), 189–197.
8. Bille, P.G., Buys, E., Taylor, J.R.N., The technology and properties of Omashikwa, a traditional fermented buttermilk produced by small-holder milk producers in Namibia. Int. J. Food Sci. Technol. 42 (2007), 620–624.
9. Bosire, C.K., Ogutu, J.O., Said, M.Y., Krol, M.S., Leeuw, J.d., Hoekstra, A.Y., Trends and spatial variation in water and land footprints of meat and milk production systems in Kenya. Agric. Ecosyst. Environ. 205 (2015), 36–47.
10. Byers, K.E., Anglim, A.M., Anneski, C.J., Germanson, T.P., Gold, H.S., Durbin, L.J., Simonton, B.M., Farr, B.M., A hospital epidemic of vancomycin-resistant Enterococcus: risk factors and control. Infect. Control Hosp. Epidemiol. 22 (2001), 140–147.
11. Cardoso, L.A., Environmental and economic impacts of livestock productivity increase in sub-Saharan Africa. Trop. Anim. Health Prod. 44 (2012), 1879–1884.
12. Chow, J., Tang, H., Mazmanian, S.K., Pathobionts of the gastrointestinal microbiota and inflammatory disease. Curr. Opin. Immunol. 23 (2011), 473–480.
13. Dean, A.S., Crump, L., Greter, H., Schelling, E., Zinsstag, J., Global burden of human brucellosis: a systematic review of disease frequency. PLoS Negl. Trop. Dis., 6, 2012, e1865.
14. Dean, A.S., Fournié, G., Kulo, A.E., Boukaya, G.A., Schelling, E., Bonfoh, B., Potential risk of regional disease spread in West Africa through cross-border cattle trade. PLoS One, 8, 2013, e75570.
15. Delorme, C., Abraham, A.L., Renault, P., Guédon, E., Genomics of Streptococcus salivarius, a major human commensal. Infect. Genet. Evol. 33 (2015), 381–392.
16. Díaz-Ruiz, G., Guyot, J.P., Ruiz-Teran, F., Morlon-Guyot, J., Wacher, C., Microbial and physiological characterization of weakly amylolytic but fast-growing lactic acid bacteria: a functional role in supporting microbial diversity in pozol, a Mexican fermented maize beverage. Appl. Environ. Microbiol. 69 (2003), 4367–4374.
17. Dirar, H.A., The Indigenous Fermented Foods of the Sudan: A Study in African Food and Nutrition. 1993, CAB International, Wallingford, UK.
18. Doutoum, A.A., Tidjani, A., Balde, M., Tidjani, S.M.T., Abdelaziz Arada, I., Sylla, K.S.B., Seydi, M.G., Toguebaye, B.S., Identification of lactic bacteria of milk quail in Chad. J. Appl. Biol. Biotechnol. 1 (2013), 007–015.
19. Dumke, J., Hinse, D., Vollmer, T., Knabbe, C., Dreier, J., Development and application of a multilocus sequence typing scheme for Streptococcus gallolyticus subsp. gallolyticus. J. Clin. Microbiol. 52 (2014), 2472–2478.
20. EFSA Panel on Biological Hazards, Update of the list of QPS-recommended biological agents intentionally added to food or feed as notified to EFSA 4: suitability of taxonomic units notified to EFSA until March 2016. EFSA J., 14, 2016 (e04522-n/a).
21. El-Baradei, G., Delacroix-Buchet, A., Ogier, J.C., Bacterial biodiversity of traditional Zabady fermented milk. Int. J. Food Microbiol. 121 (2008), 295–301.
22. Facklam, R.R., What happened to the streptococci: overview of taxonomic and nomenclature changes. Clin. Microbiol. Rev. 15 (2002), 613–630.
23. FAO, Pastoralism in the New Millennium. 2001, Food and Agriculture Organisation, Rome, Italy.
24. FAOSTAT, FAOSTAT Database. 2015, FAO, Rome, Italy http://faostat3.fao.org/home/E (Access Date: 2015-June-05).
25. Fischer, A., Liljander, A., Kaspar, H., Muriuki, C., Fuxelius, H.H., Bongcam-Rudloff, E., de Villiers, E.P., Huber, C.A., Frey, J., Daubenberger, C., Bishop, R., Younan, M., Jores, J., Camel Streptococcus agalactiae populations are associated with specific disease complexes and acquired the tetracycline resistance gene tetM via a Tn916-like element. Vet. Res., 44, 2013, 86.
26. Fisher, K., Phillips, C., The ecology, epidemiology and virulence of Enterococcus. Microbiol.-SGM 155 (2009), 1749–1757.
27. Franz, C.M.A.P., Holzapfel, W.H., Stiles, M.E., Enterococci at the crossroads of food safety?. Int. J. Food Microbiol. 47 (1999), 1–24.
28. Franz, C.M.A.P., Huch, M., Mathara, J.M., Abriouel, H., Benomar, N., Reid, G., Galvez, A., Holzapfel, W.H., African fermented foods and probiotics. Int. J. Food Microbiol. 190 (2014), 84–96.
29. Fratkin, E., Roth, E., Nathan, M., Pastoral sedentarization and its effects on children's diet, health, and growth among Rendille of Northern Kenya. Hum. Ecol. 32 (2004), 531–559.
30. Godfree, A.F., Kay, D., Wyer, M.D., Faecal streptococci as indicators of faecal contamination in water. Soc. Appl. Bacteriol. Symp. Ser 83 (1997), 110S–119S.
31. Gonfa, A., Fite, A., Urga, K., Gashe, B.A., Microbiological aspects of Ergo (Ititu) fermentation. Ethiop. J. Sci. 22 (1999), 283–290.
32. Grimaud, P., Sserunjogi, M., Wesuta, M., Grillet, N., Kato, M., Faye, B., Effects of season and agro-ecological zone on the microbial quality of raw milk along the various levels of the value chain in Uganda. Trop. Anim. Health Prod. 41 (2009), 883–890.
33. Gustavsson, J., Cederberg, C., Sonesson, U., van Otterdijk, R., Meybeck, A., Global food losses and food waste - extent, causes and prevention. Study Conducted for the International Congress “Save Food!” at Interpack2011, Düsseldorf, Germany, 2011, FAO, Rome, Italy.
34. Hammes, W.P., Hertel, C., Genus I. Lactobacillus. De Vos, P., Garrity, G.M., Jones, D., Krieg, N.R., Ludwig, W., Rainey, F.A., Schleifer, K.-H., Whitman, W.B., (eds.) Bergey's Manual of Systematic Bacteriology. The Firmicutes, second ed., 2009, Springer, New York, NY, USA, 465–511.
35. Hassaïne, O., Zadi-Karam, H., Karam, N.E., Technologically important properties of lactic acid bacteria isolated from raw milk of three breeds of Algerian dromedary (Camelus dromedarius). Afr. J. Biotechnol. 6 (2007), 1720–1727.
36. Havelaar, A.H., Kirk, M.D., Torgerson, P.R., Gibb, H.J., Hald, T., Lake, R.J., Praet, N., Bellinger, D.C., de Silva, N.R., Gargouri, N., Speybroeck, N., Cawthorne, A., Mathers, C., Stein, C., Angulo, F.J., Devleesschauwer, B., World Health Organization Foodborne Disease Burden Epidemiology Reference Group, World Health Organization global estimates and regional comparisons of the burden of foodborne disease in 2010. PLoS Med., 12, 2015, e1001923.
37. Iannotti, L., Lesorogol, C., Animal milk sustains micronutrient nutrition and child anthropometry among pastoralists in Samburu, Kenya. Am. J. Phys. Anthropol. 155 (2014), 66–76.
38. Isono, Y., Shingu, I., Shimizu, S., Identification and characteristics of lactic acid bacteria isolated from Masai fermented milk in northern Tanzania. Biosci. Biotechnol. Biochem. 58 (1994), 660–664.
39. Jans, C., Bugnard, J., Njage, P.M.K., Lacroix, C., Meile, L., Lactic acid bacteria diversity of African raw and fermented camel milk products reveals a highly competitive, potentially health-threatening predominant microflora. LWT Food Sci. Technol. 47 (2012), 371–379.
40. Jans, C., Gerber, A., Bugnard, J., Njage, P.M.K., Lacroix, C., Meile, L., Novel Streptococcus infantarius subsp. infantarius variants harboring lactose metabolism genes homologous to Streptococcus thermophilus. Food Microbiol. 31 (2012), 33–42.
41. Jans, C., Follador, R., Hochstrasser, M., Lacroix, C., Meile, L., Stevens, M.J.A., Comparative genome analysis of Streptococcus infantarius subsp. infantarius CJ18, an African fermented camel milk isolate with adaptations to dairy environment. BMC Genomics, 14, 2013, 200.
42. Jans, C., Kaindi, D.W.M., Böck, D., Njage, P.M.K., Kouamé-Sina, S.M., Bonfoh, B., Lacroix, C., Meile, L., Prevalence and comparison of Streptococcus infantarius subsp. infantarius and Streptococcus gallolyticus subsp. macedonicus in raw and fermented dairy products from East and West Africa. Int. J. Food Microbiol. 167 (2013), 186–195.
43. Jans, C., Meile, L., Lacroix, C., Stevens, M.J.A., Genomics, evolution, and molecular epidemiology of the Streptococcus bovis/Streptococcus equinus complex (SBSEC). Infect. Genet. Evol. 33 (2015), 419–436.
44. Jans, C., de Wouters, T., Bonfoh, B., Lacroix, C., Kaindi, D.W.M., Anderegg, J., Böck, D., Vitali, S., Schmid, T., Isenring, J., Kurt, F., Kogi-Makau, W., Meile, L., Phylogenetic, epidemiological and functional analyses of the Streptococcus bovis/Streptococcus equinus complex through an overarching MLST scheme. BMC Microbiol., 16, 2016, 117.
45. Jans, C., Kaindi, D.W.M., Meile, L., Innovations in food preservation in pastoral zones. Rev. Sci. Tech. 35 (2016), 597–610.
46. Jans, C., Merz, A., Johler, S., Younan, M., Tanner, S.A., Kaindi, D.W.M., Wangoh, J., Bonfoh, B., Meile, L., Tasara, T., East and West African milk products are reservoirs for human and livestock-associated Staphylococcus aureus. Food Microbiol. 65 (2017), 64–73.
47. Jiwoua, C., Milliere, J.B., Lactic flora and enterococci of fermented milk (Pindidam) produced in Adamaoua (Cameroon). Lait 70 (1990), 475–486.
48. Kadri, Z., Vandamme, P., Ouadghiri, M., Cnockaert, M., Aerts, M., Elfahime, E.M., El Farricha, O., Swings, J., Amar, M., Streptococcus tangierensis sp. nov. and Streptococcus cameli sp. nov., two novel Streptococcus species isolated from raw camel milk in Morocco. Anton Leeuw. Int. J. G. 107 (2015), 503–510.
49. Kamana, O., Ceuppens, S., Jacxsens, L., Kimonyo, A., Uyttendaele, M., Microbiological quality and safety assessment of the Rwandan milk and dairy chain. J. Food Prot. 77 (2014), 299–307.
50. Kebede, A., Viljoen, B.C., Gadaga, T.H., Narvhus, J.A., Lourens-Hattingh, A., The effect of container type on the growth of yeast and lactic acid bacteria during production of Sethemi, South African spontaneously fermented milk. Food Res. Int. 40 (2007), 33–38.
51. Khedid, K., Faid, M., Mokhtari, A., Soulaymani, A., Zinedine, A., Characterization of lactic acid bacteria isolated from the one humped camel milk produced in Morocco. Microbiol. Res. 164 (2009), 81–91.
52. Kirk, M.D., Pires, S.M., Black, R.E., Caipo, M., Crump, J.A., Devleesschauwer, B., Döpfer, D., Fazil, A., Fischer-Walker, C.L., Hald, T., Hall, A.J., Keddy, K.H., Lake, R.J., Lanata, C.F., Torgerson, P.R., Havelaar, A.H., Angulo, F.J., World Health Organization estimates of the global and regional disease burden of 22 foodborne bacterial, protozoal, and viral diseases, 2010: a data synthesis. PLoS Med., 12, 2015, e1001921.
53. Le Doare, K., Heath, P.T., An overview of global GBS epidemiology. Vaccine 31:Suppl. 4 (2013), D7–D12.
54. Ludwig, W., Schleifer, K.H., Whitman, W.B., Order II. Lactobacillales ord. nov. De Vos, P., Garrity, G.M., Jones, D., Krieg, N.R., Ludwig, W., Rainey, F.A., Schleifer, K.-H., Whitman, W.B., (eds.) Bergey's Manual of Systematic Bacteriology. The Firmicutes, second ed., 2009, Springer, New York, NY, USA, 464–735.
55. Mangia, N.P., Garau, G., Murgia, M.A., Bennani, A., Deiana, P., Influence of autochthonous lactic acid bacteria and enzymatic yeast extracts on the microbiological, biochemical and sensorial properties of Lben generic products. J. Dairy Res. 81 (2014), 193–201.
56. Manning, S.D., Springman, A.C., Million, A.D., Milton, N.R., McNamara, S.E., Somsel, P.A., Bartlett, P., Davies, H.D., Association of group B Streptococcus colonization and bovine exposure: a prospective cross-sectional cohort study. PLoS One, 5, 2010, e8795.
57. Mapekula, M., Chimonyo, M., Mapiye, C., Dzama, K., Milk production and calf rearing practices in the smallholder areas in the Eastern Cape Province of South Africa. Trop. Anim. Health Prod. 41 (2009), 1475–1485.
58. Mathara, J.M., Schillinger, U., Kutima, P.M., Mbugua, S.K., Holzapfel, W.H., Isolation, identification and characterisation of the dominant microorganisms of kule naoto: the Maasai traditional fermented milk in Kenya. Int. J. Food Microbiol. 94 (2004), 269–278.
59. Mbawala, A., Mahbou, P.Y., Mouafo, H.T., Tatsadjieu, L.N., Antibacterial activity of some lactic acid bacteria isolated from a local fermented milk product (pendidam) in Ngaoundere, Cameroon. J. Anim. Plant Sci. 23 (2013), 157–166.
60. Mpofu, A., Linnemann, A.R., Nout, M.J., Zwietering, M.H., Smid, E.J., Mutandabota, a food product from Zimbabwe: processing, composition, and socioeconomic aspects. Ecol. Food Nutr. 53 (2014), 24–41.
61. Müller, B., Dürr, S., Alonso, S., Hattendorf, J., Laisse, C.J., Parsons, S.D., van Helden, P.D., Zinsstag, J., Zoonotic Mycobacterium bovis-induced tuberculosis in humans. Emerg. Infect. Dis. 19 (2013), 899–908.
62. Ndambi, O.A., Garcia, O., Balikowa, D., Kiconco, D., Hemme, T., Latacz-Lohmann, U., Milk production systems in Central Uganda: a farm economic analysis. Trop. Anim. Health Prod. 40 (2008), 269–279.
63. Nieminen, M.T., Novak-Frazer, L., Collins, R., Dawsey, S.P., Dawsey, S.M., Abnet, C.C., White, R.E., Freedman, N.D., Mwachiro, M., Bowyer, P., Salaspuro, M., Rautemaa, R., Alcohol and acetaldehyde in African fermented milk mursik–a possible etiologic factor for high incidence of esophageal cancer in western Kenya. Cancer Epidemiol. Biomark. Prev. 22 (2013), 69–75.
64. Njage, P.M.K., Dolci, S., Jans, C., Wangoh, J., Lacroix, C., Meile, L., Characterization of yeasts associated with camel milk using phenotypic and molecular identification techniques. Res. J. Microbiol. 6 (2011), 678–692.
65. Noor, I.M., Guliye, A.Y., Tariq, M., Bebe, B.O., Assessment of camel and camel milk marketing practices in an emerging peri-urban production system in Isiolo County, Kenya. Pastoralism, 3, 2013, 28.
66. Nyambane, B., Thari, W.M., Wangoh, J., Njage, P.M., Lactic acid bacteria and yeasts involved in the fermentation of amabere amaruranu, a Kenyan fermented milk. Food Sci. Nutr. 2 (2014), 692–699.
67. Obodai, M., Dodd, C.E., Characterization of dominant microbiota of a Ghanaian fermented milk product, nyarmie, by culture- and nonculture-based methods. J. Appl. Microbiol. 100 (2006), 1355–1363.
68. Ogier, J., Serror, P., Safety assessment of dairy microorganisms: the Enterococcus genus. Int. J. Food Microbiol. 126 (2008), 291–301.
69. Oguntoyinbo, F.A., Tourlomousis, P., Gasson, M.J., Narbad, A., Analysis of bacterial communities of traditional fermented West African cereal foods using culture independent methods. Int. J. Food Microbiol. 145 (2011), 205–210.
70. Osvik, R.D., Sperstad, S., Breines, E., Hareide, E., Godfroid, J., Zhou, Z., Ren, P., Geoghegan, C., Holzapfel, C., Ringø, E., Bacterial diversity of aMasi, a South African fermented milk product, determined by clone library and denaturing gradient gel electrophoresis analysis. Afr. J. Microbiol. Res. 7 (2013), 4146–4158.
71. Ouadghiri, M., Vancanneyt, M., Vandamme, P., Naser, S., Gevers, D., Lefebvre, K., Swings, J., Amar, M., Identification of lactic acid bacteria in Moroccan raw milk and traditionally fermented skimmed milk ‘lben’. J. Appl. Microbiol. 106 (2009), 486–495.
72. Quigley, L., McCarthy, R., O'Sullivan, O., Beresford, T.P., Fitzgerald, G.F., Ross, R.P., Stanton, C., Cotter, P.D., The microbial content of raw and pasteurized cow milk as determined by molecular approaches. J. Dairy Sci. 96 (2013), 4928–4937.
73. Quigley, L., O'Sullivan, O., Stanton, C., Beresford, T.P., Ross, R.P., Fitzgerald, G.F., Cotter, P.D., The complex microbiota of raw milk. FEMS Microbiol. Rev. 37 (2013), 664–698.
74. Ranciaro, A., Campbell, Michael C., Hirbo, Jibril B., Ko, W.-Y., Froment, A., Anagnostou, P., Kotze, Maritha J., Ibrahim, M., Nyambo, T., Omar, Sabah A., Tishkoff, Sarah A., Genetic origins of lactase persistence and the spread of pastoralism in Africa. Am. J. Hum. Genet. 94 (2014), 496–510.
75. Rashid, M.H., Togo, K., Ueda, M., Miyamoto, T., Identification and characterization of dominant lactic acid bacteria isolated from traditional fermented milk ‘Dahi’ in Bangladesh. World J. Microbiol. Biotechnol. 23 (2007), 125–133.
76. Sanogo, S., Shaker, M.M., Nantoume, H., Salem, A.F., Milk yield and composition of crossbred Sahelian × Anglo-Nubian goats in the semi-intensive system in Mali during the preweaning period. Trop. Anim. Health Prod. 45 (2013), 305–310.
77. Schlegel, L., Grimont, F., Ageron, E., Grimont, P.A.D., Bouvet, A., Reappraisal of the taxonomy of the Streptococcus bovis/Streptococcus equinus complex and related species: description of Streptococcus gallolyticus subsp. gallolyticus subsp. nov., S. gallolyticus subsp. macedonicus subsp. nov. and S. gallolyticus subsp. pasteurianus subsp. nov. Int. J. Syst. Evol. Microbiol. 53 (2003), 631–645.
78. Schönfeldt, H.C., Gibson Hall, N., Dietary protein quality and malnutrition in Africa. Br. J. Nutr. 108:Suppl. 2 (2012), S69–S76.
79. Schoustra, S.E., Kasase, C., Toarta, C., Kassen, R., Poulain, A.J., Microbial community structure of three traditional Zambian fermented products: Mabisi, Chibwantu and Munkoyo. PLoS One, 8, 2013, e63948.
80. Shibata, Y., Tien le, H.T., Nomoto, R., Osawa, R., Development of a multilocus sequence typing scheme for Streptococcus gallolyticus. Microbiology 160 (2014), 113–122.
81. Swiss Commission for Research Partnerships with Developing Countries (KFPE), A Guide for Transboundary Research Partnerships - 11 Principles. second ed., 2014, Swiss Academy of Sciences, Bern, Switzerland.
82. Teuber, M., Genus II. Lactococcus. De Vos, P., Garrity, G.M., Jones, D., Krieg, N.R., Ludwig, W., Rainey, F.A., Schleifer, K.-H., Whitman, W.B., (eds.) Bergey's Manual of Systematic Bacteriology. The Firmicutes, second ed., 2009, Springer, New York, NY, USA, 711–722.
83. The World Bank, World Population Data. 2015, The World Bank, Washington, DC, USA http://data.worldbank.org/indicator/SP.POP.TOTL/countries?display=default (Accession Date: 2015-March-03).
84. U.S. Food & Drug Administration FDA, GRAS Notice Inventory. 2017, U.S. Food & Drug Administration, Silver Spring, MD, USA https://www.fda.gov/Food/IngredientsPackagingLabeling/GRAS/NoticeInventory/default.htm (Accession Date: 2017-March-03).
85. Whiley, R.A., Hardie, J.M., Genus I. Streptococcus. De Vos, P., Garrity, G.M., Jones, D., Krieg, N.R., Ludwig, W., Rainey, F.A., Schleifer, K.-H., Whitman, W.B., (eds.) Bergey's Manual of Systematic Bacteriology. The Firmicutes, second ed., 2009, Springer, New York, NY, USA, 655–711.
86. Witthuhn, R.C., Schoeman, T., Britz, T.J., Isolation and characterization of the microbial population of different South African kefir grains. Int. J. Dairy Technol. 57 (2004), 33–37.
87. Wuehler, S.E., Hess, S.Y., Brown, K.H., Accelerating improvements in nutritional and health status of young children in the Sahel region of Sub-Saharan Africa: review of international guidelines on infant and young child feeding and nutrition. Matern. Child Nutr. 7 (2011), 6–34.
88. Wullschleger, S., Lacroix, C., Bonfoh, B., Sissoko-Thiam, A., Hugenschmidt, S., Romanens, E., Baumgartner, S., Traoré, I., Yaffee, M., Jans, C., Meile, L., Analysis of lactic acid bacteria communities and their seasonal variations in a spontaneously fermented dairy product (Malian fènè) by applying a cultivation/genotype-based binary model. Int. Dairy J. 29 (2013), 28–35.
89. Wurzinger, M., Okeyo, A.M., Semambo, D., Sölkner, J., The sedentarisation process of the Bahima in Uganda: an emic view. Afr. J. Agric. Res. 4 (2009), 1154–1158.
90. Zadoks, R.N., Middleton, J.R., McDougall, S., Katholm, J., Schukken, Y.H., Molecular epidemiology of mastitis pathogens of dairy cattle and comparative relevance to humans. J. Mammary Gland Biol. Neoplasia 16 (2011), 357–372.
91. Zinsstag, J., Schelling, E., Daoud, S., Schierle, J., Hofmann, P., Diguimbaye, C., Daugla, D.M., Ndoutamia, G., Knopf, L., Vounatsou, P., Tanner, M., Serum retinol of Chadian nomadic pastoralist women in relation to their livestocks' milk retinol and beta-carotene content. Int. J. Vitam. Nutr. Res. 72 (2002), 221–228.