- Probiotic microorganisms in food. Properties, benefits, safety and enumeration
- What are probiotics?
- Benefits claimed for the ingestion of probiotic bacteria
- Probiotic bacteria and other microorganisms
- Characteristics of bifidobacteria
- Mechanisms postulated for the beneficial effects of probiotic bacteria
- Safety of probiotics
- Selection of probiotics
- Minimum concentration of probiotic required for beneficial effect
- Enumeration of probiotic bacteria
- Media for the isolation of probiotic bacteria.
- Survival of probiotic bacteria in commercial yoghurt products
- Some product development considerations
- European Community Regulation no 1924/2006 and health and nutrition claims
- All Pages
Selection of probiotics
Not all strains of Lb. acidophilus, Bifidobacterium species and Lb. casei are suitable for use as probiotics. The following criteria have been used or suggested for use in strain selection: -
• Origin. Strain should have originated from the human GI-tract
• Safety. Strain should be non-pathogenic. It should also be sensitive to common antibiotics and not harbour antibiotic resistance or virulence plasmids. Additionally I would also wish to ensure that strains that produce biogenic amines are excluded.
• Withstand host's natural barriers. Essentially be able to survive transit through the GI tract. This will mean resistance to bile salts, low pH and proteases in initial in vitro screening.
• Adherence to intestinal epithelium. The ability to adhere to intestinal cells and effectively block sites that could be occupied by pathogens.
• Commercial propagation. Strain must be able to grow in under commercial conditions and should retain viability under normal commercial storage conditions.
• Functional properties. The strain should meet the definition of a probiotic in clinical trials!