Xylitol

Origin

Xylitol can be naturally found in several fruits and vegetables and is formed as an intermediary product from carbohydrates metabolism in the liver. It was first isolated in 1891 by the German chemist Emil Fischer.¹ In the 1940s, efforts began to produce xylitol from xylose and later in 1960s, a commercial process for the production was developed.¹

Today, xylitol is used as a sweetener and a bulking agent in a variety of low calorie food products.¹

Function

Xylitol is a sweetener with a similar flavor profile to sucrose. It has a characteristic cooling effect and can also contributes to volume and texture in baked goods.² As a sweetener, it works synergistically when combined with several high intensity sweeteners like aspartame, and aids in masking undesirable aftertaste.²

Nutrition

Xylitol provides 2,5 calories per gram of product. It is partially metabolized by the organism. As a low calorie sweetener, it doesn’t have a recognized effect on insulin levels, and it’s considered non-cariogenic.²

Commercial production

This ingredient is commercially produced through the following processes:^1,3

Chemical process

• Hydrolysis: hemicellulose from wood chips are hydrolyzed with a mineral acid to produce xylose.
• Hydrogenation: xylose is transformed into xylitol by a catalytic hydrogenation reaction at 80 – 140 ^oC ( 176 – 284 ^oF) and hydrogen pressures of up to 50 atm.
• Chromatographic purification: to remove other polyols that may be present at low concentrations in the solution.
• Crystallization
• Centrifuging
• Drying
• Sieving
• Packaging

Biological process³

• A microbiological process can be used to produce xylitol from pure xylose or hemicellulose hydrolyzate using bacteria, fungi or yeast.
• An enzymatic process can be used to produce xylitol from xylose, using Candida pelliculosa coupled with Methanobacterium

Application

Xylitol is commonly used in reduced calorie food products such as:¹

• Carbonated beverages
• Dairy products and edibles ices
• Baked goods
• Cereals
• Sweets and chewing gums
• Jams, marmalades and preserves
• Chocolate

In addition to imparting sweetness, xylitol is used as an effective humectant in cakes and muffins, this contributes to:¹

• Improvement of texture and shelf-life of baked goods
• Moister texture
• Improved surface appearance and structure of baked goods

Another characteristic of xylitol is the absence of reducing groups. So, it doesn’t participate in browning Maillard reactions, and thus produces lighter colored baked goods. In creams and fillings, it provides a pleasant cooling effect that may enhance products’ flavor and add a sense of freshness and juiceness in fruit flavored fillings.¹

Regulations

Xylitol is a food additive permitted for direct addition in food products provided that its usage level does not exceed the amount required to produce the desired effect.⁴

In the EU, xylitol (E 967) is considered safe for use as a food additive by the EU Regulation N^o 1333/2008.⁵

References

1. Mitchell, H. Sweeteners and sugar alternatives in food technology. John Wiley & Sons, 2008.
2. O’Brien-Nabors, L. Alternative Sweeteners, Fourth Edition, Revised and Expanded. Switzerland, Taylor & Francis, 2001.
3. Rafiqul, I. S. M., and AM Mimi Sakinah. “Processes for the production of xylitol—a review.” Food Reviews International 29.2 (2013): 127-156.
4. Food and Drug Administration (FDA). US Department of Health and Human Services. CFR Code of Federal Regulations Title 21, Part 172 Food Additives Permitted For Direct Addition To Food For Human Consumption, https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/cfrsearch.cfm?fr=172.395 , Accessed 27 July 2021.
5. European Commission (EC). Commission Regulation (EU) No 1333/2008 of the European Parliament and of the Council of 16 December 2008 on food additives . Official Journal Of European Communities, 16 December 2008.