Probiotic fermented foods

To ensure the safety of food products, representative samples must be inspected so that foodborne bacteria can be identified.15,18,19 Bacteria producing heat-stable enterotoxins, such as Staphylococcus aureus, may be identified by biochemical and serological techniques.20,21 Molecular methods are now widely used for the identification of many pathogenic foodborne bacteria,15,22,23 In addition bacteria used as starter cultures for cheese, yogurt, other fermented foods and beverages, and probiotic dietary supplements may be identified for quality assurance.22,24,25... 

Parvez, S., Malik, K.A., Ah Kang, S., and Kim, H.-Y. 2006. Probiotics and their fermented food products are beneficial for health. JAppl Microbiol 100 1171-1185. 

Stanton, C., Desmond, C., Coakley, M., Collins, J.K., Fitzgerald, G.E, and Ross, R.R Challenges facing development of probiotic-containing functional foods. Handbook of Fermented Foods, E.R. Famworth, ed., CRC Press, Boca Raton, FL, pp. 27-58, 2003. 

Production of fermented foods, probiotics (microbial dietary supplements). Genomic analysis should yield functional information to enable the design of lactic acid bacteria (e.g., Lactobacillus and Bifidobacterium) better suited to industrial processes or tailored to provide nutritional benefit. 

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]. 

In this chapter, an array of multiple applications of LAB for the elaboration of fermented foods and production of industrially interesting metabolites such as food ingredients, nutraceutics, and commodity chemicals was presented. Additionally, new biotechnological approaches for the production of these compounds were described. The metabolic versatility of this bacterial group demonstrates their potential for their use as cell factories beyond their classical use as food starter cultures and preservatives or as probiotics. These bacteria have been systematically assayed for novel specific traits or applications due to the availability of new molecular techniques and the consumers demands for healthier foods. LAB, considered the horsepower of the food industry, have been the focus of numerous studies to increase their product yields and repertoire. 

Although probiotics are widely consumed as dietary supplements, the focus of the present chapter is on fermented probiotic foods. Most commercially available probiotics belong to the genera Bifidobacterium and Lactobacillus strains from other genera are being marketed as well, but these rarely find application in fermented foods and will thus not be discussed here. 

Numerous fermented foods exist, but not all of these food classes can be linked with the probiotic concept, such as alcoholic beverages and fermented meats, or foods in which the fermentations merely fulfil a technological function in the processing of the food, such as in coffee, tea and cocoa. 

New strains will likely be introduced into the market. In addition to strains from the genera Lactobacillus and Bifidobacterium, strains from other genera, such as Pro-pionibacterium and Lactococcus, commonly found in fermented foods, are likely to receive more attention. But strains from new probiotic genera are also likely to emerge, such as butyrate-producing Roseburia and Clostridium, or strains from the anti-inflammatory species F. prausnitzii. 

To what extent strains from such new probiotic species can and will be incorporated into fermented foods is uncertain. Likewise, it is uncertain whether these and other new health targets are suitable for fermented foods. What is certain, however, is that the one-strain-suits-all approach that has been common until now is going to change. A single strain is simply not able to perform the varied functions that are required to tackle various health risks the emergence of health benefit-specific strains should be anticipated. Similarly, one could anticipate that more complex mixtures might be more efficacious, as they could provide a multitude of functions to microbiota in disarray. 

Heller, K. J. (2001). Probiotic bacteria in fermented foods product characteristics and starter organisms. American Journal of Clinical Nutrition, 73(2), 374S-379S. 

Florence, A. C. R., B6al, C., Silva, R. C., Bogsan, C. S. B., PiUeggi, A. L. O.S., Gioielli, L. A., et al. (2012). Fatty acid profile, trans-octadecenoic, a-linolenic and conjngated linoleic acid contents differing in certified organic and conventional probiotic fermented milks. Food Chemistry, 135, 2207-2214. 

The use of probiotic LAB, especially Lactobacillus and Bifidobacterium spp., as starter cultures, alone or in combination with traditional starter cultures in various fermentation processes, has been explored for different fermentation food products. Formulated fermented probiotic food may present consumers with a healthy dietary component at a considerabley low cost (Goldin, 1998). Furthermore, it was reported that LAB may contribute to microbiological safety and/or provide one or more technological, nutritional and organoleptic advantages to a fermented product, through production of ethanol, acetic acid, aroma compounds, exopolysaccharides, bacteriocins and several enzymes (Leroy De Vuyst, 2004). 

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