Abstract
Probiotic bacteria, according to the definition adopted by the World Health Organization in 2002, are live microorganisms, which when administered in adequate amounts confer a health benefit to the host. Recent studies show that the same probiotic strain produced and/or preserved under different storage conditions, may present different responses regarding their susceptibility to the adverse conditions of the gastrointestinal tract, its capacity to adhere to the intestinal epithelium, or its immunomodulating capacity, the functionality being affected without changes in cell viability. This could imply that the control of cell viability is not always enough to guarantee the functionality (probiotic capacity) of a strain. Therefore, a new challenge arises for food technologists and microbiologists when it comes to designing and monitoring probiotic food: to be able to monitor the functionality of a probiotic microorganism throughout all the stages the strain goes through from the moment it is produced and included in the food vehicle, until the moment of consumption. Conventional methodological tools or others still to be developed must be used. The application of cell membrane functionality markers, the use of tests of resistance to intestinal barriers, the study of surface properties and the application of in vivo models come together as complementary tools to assess the actual capacity of a probiotic organism in a specific food, to exert functional effects regardless of the number of viable cells present at the moment of consumption.
Highlights
Probiotic bacteria, according to the definition adopted by the World Health Organization in 2002, are live microorganisms, which when administered in adequate amounts confer a health benefit to the host
It was established that probiotics are “live microorganisms which when administered in adequate amounts confer a health benefit on the host.” (WHO/Food and Agriculture Organization (FAO), 2002)
In relation to these results, our group recently showed (Vinderola et al, 2011) that different L. casei strains in fermented milks of different flavors, which maintained adequate levels of viable cells during refrigerated storage, experienced changes in gastric resistance depending on the temperature of storage (5 or 12°C, an usual temperature on supermarket shelves), during the storage period, and on the flavor of the fermented milk. These factors resulted in an increase or decrease of gastric resistance, as a result of the possible simultaneous presence of sublethal stress factors that might induce gastric resistance as well as the presence of factors having inhibitory potential, such as chemical agents used in the formulation of commercial dairy products. These results indicate that the same probiotic strain can present different behaviors in terms of gastric resistance according to the flavor of the fermented milk to which is added, stressing the need for adequate viability and functionality controls when it comes to developing a new probiotic food, even when it may be similar to other products already existing in the market, as in the case of fermented milks of different flavors
Summary
Instituto de Lactología Industrial, Facultad de Ingeniería Química, Universidad Nacional del Litoral, Santa Fe, Argentina. Certain species of the genera Bifidobacterium and Lactobacillus, common inhabitants of the intestinal microbiota, are traditionally regarded as microorganisms beneficial to health, due to the fact they exclusively promote healthy effects in their natural niche. Some of these strains show an adequate tolerance to gastrointestinal barriers and to technological parameters applied in the production of food. Even though there is an increasingly marked tendency to apply advanced techniques such as FISH, flow cytometry (Ben Amor et al, 2007), and real-time quantitative www.frontiersin.org
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
