The sugar alcohol lactitol, commonly used as a sweetener, can positively affect the population of beneficial bacteria in the intestine, and may be considered a novel prebiotic, researchers have reported.
Writing in the European Journal of Nutrition, researchers from University of Salford and Purac Biochem report that consumption of lactitol-rich chocolate resulted in significant improvements in bifidobacteria populations, suggesting the potential prebiotic activity of the sweetener.
Prebiotic ingredients, or those that boost the growth of beneficial probiotic bacteria in the gut, are worth about €90 million in the European marketplace but are forecast to reach €179.7 million by 2010, according to Frost & Sullivan.
The market has been largely created by three inulin producers, all based in Europe, but other ingredient manufacturers are increasingly looking to promote the prebiotic effect of their products as evidence suggests that prebiotics could be even more useful than the probiotic bacteria that they feed.
Prebiotics, which are derived from insoluble fibres and oligosaccharides, can be incorporated into a wider variety of end products than probiotic bacteria. They have also benefited from the promotional efforts of probiotic suppliers, who have significantly raised public awareness of gut health in recent years.
The new study looked at the potential of lactitol (4-beta-d-galactopyranosyl-d-glucitol) to affect intestinal microflora populations. Seventy-five health adults were recruited for the study and asked to consume 25 gram tables of milk chocolate containing ten grams of sweetener defined as a ratio of sucrose to lactitol every day for seven days. The ratios of sucrose:lactitol used were 10:0, 5:5 or 0:10.
Lead author Michelle Finney and co-workers report that only the 0:10 sucrose to lactitol ratio produced significant increases in bifidobacteria counts. This was accompanied by a decrease in the pH of the subjects' faeces, and significant increases in the concentrations of propionic and butyric acids.
The increase in the concentration of these organic acids is a positive result as they are involved in a wide range of physiological functions.
"The results show that low doses of lactitol can beneficially affect the faecal flora without eliciting gross symptoms of intolerance and that lactitol can be classified as a prebiotic," stated the researchers.
In terms of adverse events, Finney and co-workers report that daily consumption of 10 grams of lactitol only produce a "few adverse symptoms of gastrointestinal intolerance"
The increased consumer understanding of prebiotic and probiotics has resulted in impressive growth for these ingredients. This has sparked interest in the identification of other sources of the ingredients.
Indeed, in recent months researchers around the globe have reported on the potential of brown algae and corn cobs, for example, to offer alternative sources of prebiotics.
Source: European Journal of Nutrition
Septembre 2007, Volume 46, Number 6, Pages 307-314. Doi: 10.1007/s00394-007-0666-7
"Effects of low doses of lactitol on faecal microflora, pH, short chain fatty acids and gastrointestinal symptomology"
Authors: M. Finney, J. Smullen, H.A. Foster, S. Brokx and D.M. Storey