What is in prebiotic?

Compounds in the non-digestible fiber of food provide the ‘fuel’ that stimulates the growth and/or activity of beneficial bacteria in the colon. The increased activity of these health-promoting bacteria results in a number of health-related benefits both directly by the bacteria themselves or indirectly by the organic acids they produce via fermentation.

Good bacteria use both resistant starch as well as non-starch polysaccharides compounds in prebiotic food such as cellulose, hemicellulose, inulin, galacto-oligosaccharide (GOS), fructooligosaccharides (FOS), xylooligosaccharides (XOS), polydextrose and   oligofructose. Arabinogalactan can be found in certain vegetables. Pectin, the soluble fiber in your apple also has prebiotic potential.

Researchers distinguish between long chain, short chain, and full spectrum prebiotics. Inulin is a long chain prebiotic fiber and is digested more slowly.  Long chain prebiotics contain 9 to 64 links per saccharide molecule, providing food for bacteria in the large intestine. Oligofructose can be digested more quickly. It is a short chain prebiotic, containing 2 to 8 links per saccharide molecule that is non-digestible only in the upper gut by humans. Full spectrum prebiotics is food that contains both long chain and short chain fiber.

Inulin is the most easily available commercially in the market. It has specific technological advantages, being soluble upon heating and bland in taste. It can be blended into a large number of different food products which retain their intrinsic flavor without alteration of texture and appearance. Inulin helps to provide body, good mouth-feel and appearance, thus it can be used as a fat replacer for the emerging sector of lower energy food products [Franck, 2002]. 

When we eat food with prebiotic compounds, this is what happens when the food travel from the mouth down the GI tract:

·         Mouth- Not broken down by enzymes, minimal bacterial breakdown

·         Stools- No prebiotic excretion

·         Stomach- Not broken down by stomach acids, no absorption

·         Small intestine- No enzymatic hydrolysis, no absorption

·         Colon- Probiotics such as Lactobacilli and Bifidobacteria ferments the prebiotic fibers for fuel, producing acids such as lactic acid, acetic acid, butyric acid etc., which inhibits or kill harmful microbes. The fermentation process does not produce toxicity, carcinogenicity or genotoxicity.

Next time you tuck into a fiber rich meal, you know that you are giving both yourself and your friendly tenants in the gut a healthy, good meal.