Xylitol –A healthy substitute for sugar


Dr Loveleen Kaur Sarao
Punjab Agricultural University, Ludhiana

Xylitolis a five-carbon sugar alcohol that is found in small quantities in many fruitsand vegetables. Xylitol is a naturally occurring pentahydroxysugar alcohol having high sweetening power. Its ability in being used as analternative to sucrose, has directed attention towards its differentapplications specially in foods, pharmaceuticals and related medical products. Xylitol is widelyused in "sugar-free" chewing gums, mints, and other candies as asugar substitute. Due to its unique pharmacological properties, worldwidedemand is ever increasing.


Xylitoloccurs in the human body as a normal intermediate of carbohydrate metabolism.Sweetening power of xylitol is similar to that of sucrose. Unlike sucrose,xylitol is not metabolized by Streptococci in the mouth and therefore,xylitol-sweetened foods barely cause any tooth decay in the absence of othercarbohydrates that may be susceptible to bacterial action. Furthermore, xylitolis a fully metabolizable sugar substitute for diabetics. Increasing amounts ofxylitol are being used as sweetener in the food industry.


Xylitol is a sweetener that stands outamong others because it can be used to combat dental caries, to treat illnessessuch as diabetes, disorders in lipid metabolism and parenteral and renallesions and to prevent lung infection, otitis and osteoporosis.  In context to these, the areas of interestare anticariogenic properties of this polyol and its insulin-independent metabolism.Another advantage of xylitol when compared with other sweeteners is the factthat it can be produced by a biotechnological process, which has economicpotential because it is very specific and requires less energy than a chemicalprocess.  Low concentration of xylitol infruits and vegetables has made extraction of this sugar alcohol less economicaland it’s quite difficult to carry out the process efficiently.


On an industrial scale, production ofxylitol is based on chemical separation of xylose fraction of hemicellulosicmaterials but the process is still considered expensive since thehemicellulosics also contain other types of sugars and biopolymers, which shouldbe separated from the test matrix. Focus is now directed towards use ofbiochemical routes and despite the capability of yeasts for xylitol production,there are still some problems in these types of bioconversions likepotentiality of simultaneous production of other metabolites (ethanol,glycerol, arabinol etc.). The extent of these fermentation issues could bereduced through the use of microbial screening program and preparation ofdifferent nutritive regimes for the test microorganism and choosing themicroorganism based on its potential to act selectively in response to oneparticular substrate in a multisubstrate system. Besides, xylitol production byfermentation also has great environmental impact owing to the use of low-costlignocellulosic wastes that can be found in large quantities in nature.


Xylitol can be produced from D-xylose by fermentation with yeasts.The development of an economic fermentative process forxylitol production involves the selection of yeast strains with high productivity,establishment of conditions that maximize the conversion of xylose into xylitoland optimization of these parameters for scaling up process. Forthe economical production of xylitol, the initial concentration of xyloseshould be as high as possible. Aeration also plays an important role in thebioconversion of xylose to xylitol by yeasts where a high degree of aerationpromotes cell growth, while being detrimental to xylitol accumulation.


Generally, the human bodytolerates  xylitol well , but some peopleexperience digestive side effects in case they consume too much of it. Suchpeople report of diarrhoea, bloating and gas. These side effects are ruled outin case one gives ample time for the body to adapt to it by shifting to itgradually. If your are on thelookout for a healthy sugar,  tryxylitol. It helps in dental health maintenance,  feeds the beneficial microbes in ourgut,  doesn't spike blood sugar orinsulin.