Probiotics dairy fermentations

Probiotics also play a role in dairy fermentations to assist in the preservation of milk as a result of the production of lactic acid and other antimicrobial compounds. They have other functions as well, which are not involved with preservation or organic acids (Parvez et al., 2006). 

Enterococci have featured in dairy fermentations for decades and isolates with histories of safe usage are being promoted as probiotic cultures. A variety of probiotic supplements are available for human and veterinary use. These range from fermented milks to lyophylised forms, containing both single and multiple strains. Actually about 20% of probiotic preparations in the market contains strains of enterococci - which in 50% consist from E. faecium (Ewing and Haresign 1989 Eranz et al. 1999 Hamilton-Miller et al. 1996). 

In fermented probiotic dairy products, probiotics are usually accompanied by starter cultures such as Lactobacillus delbrueckii subsp. bulgaricus and/or Staphylococcus thermophilus. There are two main reasons for the inclusion of starter cultures in a probiotic product. The first is technological starter cultures provide sttucture and flavour to the product. In addition, starter cultures support functionality some probiotics do not grow well as a pure culture in mUk and grow better in symbiosis with a starter culture. 

In addition to LAB, some PAB species used in dairy fermentation are considered good probiotic candidates in human health (Cousin et al. 2012). Members of the PAB group were identified in the poultry GIT microbiota by culture-dependent (Salanitro et al. 1978) and culture-independent techniques (Apajalahti et al. 1998). Isolates of P. acidipropionici and P. avidum were recently tested for their probiotic potential in poultry. These PAB were shown to produce short chain fatty acids (SCFA) in an in vitro cecal model at concentrations high enough to inhibit S. enterica serovar Enteritidis. Moreover, P. acidipropionici strain LET 105 was also able to compete with Salmonella for adhesion sites on the intestinal mucosa in ex vivo assays (Arganaraz-Martinez et al. 2013). 

Probiotics are live microbes that exert health benefits when ingested in sufficient quantities. Species of lactobacilli and bifidobacteria, sometimes combined with Streptococcus thermophilus, are the main bacteria used as probiotics in fermented dairy products. Most probiotic research has been done with nutra-ceutical preparations, but yogurt has been shown to alleviate lactose intolerance, prevent vaginal can-didosis in women with recurrent vaginitis, and reduce the incidence or severity of gastrointestinal infections. 

Yogurt and fermented dairy products Probiotics Improve gastrointestinal health... 

Although the safety of traditional lactic starter bacteria has never been in question, the more recent use of intestinal isolates of bacteria (bifidobacteria, intestinal lac-tobacilli, and enterococci), to be delivered as probiotics in high numbers to consumers with potentially compromised health, has raised the question of safety. These intestinal isolates do not share the centuries-old tradition of being consumed as components of fermented dairy products. However, their presence in commercial products over the past few decades has not given any indication of a safety concern. 

Lactic acid bacteria and bifidobacteria are preferred as protective and probiotic cultures, and have been used since the beginning of history as starter cultures. They have a long history of being safely used and consumed. LAB are widely used for fermentation of milk, meat, and vegetable foods. In fermentation of dairy products, lactose is metabolized to lactic acid. Other metabolic products, hydrogen peroxide, diacetyl, and bacteriocins may also play inhibitory roles and contribute to improving the organoleptic attributes of these foods, as well as their preservation (Messens and De Vuyst, 2002). 

Martinez-ViUaluenga, C. et al.. Influence of addition of raffinose family oligosaccharides on probiotic survival in fermented milk during refrigerated storage, Int. Dairy J., 16, 768, 2006. 

Shah, N.P. and Ravula, R. 2000. Microencapsulation of probiotic bacteria and their survival in frozen fermented dairy desserts. Aust. J. Dairy Technol. 55 139-144. 

Su, L.C., Lin, C.W., and Chen, M.J. 2007. Development of an oriental-style dairy product coagulated by microcapsules containing probiotics and filtrates from fermented rice. Int. J. Dairy Technol. 60 49-54. 

LAB are industrially used as starter cultures and as probiotics to perform controlled fermentations for the production of dairy, meat, vegetable, and bakery-fermented foods. L7U1 with specific characteristics have been isolated from a variety of traditional fermented products or from diverse raw materials used as starter cultures to obtain controlled and uniform fermented foods [14-16]. 

G. (2014) Kefir a multifitceted fermented dairy product. Probiot. Antimicrob. Proteins, 6, 123—135. 

Fermented dairy foods are the most widely used carriers of probiotics in Western societies, in particular yogurt and yogurt-type drink products. This may have historic reasons as mentioned above, but it has also practical reasons. Most commercially available probiotics belong to the genera Bifidobacterium and Lactobacillus. Members of these genera tend to grow well in milk, and it may even be their most common habitat. 

Besides fresh fermented dairy products, probiotics can be included in nonfermented milk such as the so-called sweet acidophilus mUk . The milk is not sweet in the sense of sweet taste, but is referred to as such because it is not sour (Mcdonough, Hitchins, Wong, Wells, Bodwell, 1987). 

Davidson, R. H., Duncan, S. E., Hackney, C. R., Eigel, W. N., Boling, J. W. (2000). Probiotic culture survival and implications in fermented frozen yogurt characteristics. Journal of Dairy Science, 83, 666-673. 

Gonzalez-Gonzalez, C. R., Tuohy, K. M., Jauregi, P. (2011). Production of angiotensin-l-con-verting enzyme (ACE) inhibitory activity in milk fermented with probiotic strains effects of calcium, pH and peptides on the ACE-inhibitory activity. Intematiorud Dairy Journal, 21, 615-622. 

Industrial Fermentation. The primary and largest industry revolves around food products. Milk from cows, sheep, goats, and horses have traditionally been used for the production of fermented dairy products. These products include cheese, sour cream, kefir, and yogurt. More recently so-called probiotics appeared and have been marketed as health-food drinks. Dairy products are produced via fermentation using lactic bacteria such as Lactobacillus acidophilus and Bifidobacterium. Fungi are also involved in making some cheeses. Fermentation produces lactic acid and other flavors and aroma compounds that make dairy products taste good. 

Boge T, Remigy M, Vaudaine S, Tanguy J, Bourdet-Sicard R, van der Werf S. A probiotic fermented dairy drink improves antibody response to influenza vacdnation in the elderly in two randomised controlled trials. Vaccine. 2009 27 5677—5684. 

Probiotics are live microorganisms usually consumed in the diet through fermented dairy foods and beverages. Fuller (1991) first defined probiotics as "live microbial food supplements that beneficially affect the host by improving the intestinal microbial balance." An updated definition was released in 2002 by the FAO/ WHO, which is the most current version "Probiotics are live microorganisms which, when administered in adequate amounts, confer a health benefit to the host." Several criteria must be met when a microorganism is proposed as a probiotic strain for human use ... 

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