Polyols, also known as sugar alcohols, are classified as carbohydrate sweeteners derived from natural. Xylitol is naturally occurring in strawberries and mushrooms, whereas Sorbitol for instance, is found in apples, pears and the fruits of the mountain ash, also known as the rowan. Mannitol for instance is found naturally occurring in kelp. These Polyols are easy to use as sugar replacers as long as their physico-chemical properties are understood.
Carbohydrate Sweeteners (Bulk)
|Common sugars||Xylose (Wood sugar)
Glucose (Grape Sugar)
Fructose (Fruit sugar)
Maltose (Malt sugar)
Lactose (Milk sugar)
Sucrose (Cone sugar)
Polyols are classified as carbohydrate sweeteners derived from natural sources. Industrially, the starting material, such as corn or tapioca starch, is hydrogenated in the presence of a catalyst.
When sucrose is heated to 160oC and above it degrade and fructose and glucose occured. After further heating to exhibit brown . Polyols are not broken down by heat and they do not exhibit colour.
When foods such as cakes are cooked there is a visible colour change due not just to the burning of the sugar but also the action of the Maillard reaction. This reaction occurs when sugars react amino acids. Polyols are created through the reaction of a sugar with hydrogen which makes them more stable, so they do not participate in the Maillard reaction and, thus, browning does not occur to the same extent.
Sucrose and other sugars will decompose under acidic conditions. Polyols do not decompose under acidic conditions which allows one to make a more stable end product.
Maltitol and Xylitol, in common with other Polyols, have a lower caloric value than sugars because they are relatively poorly absorbed in the small intestine. Food authorities around the world apply different caloric values to sugar alcohols. In the EU as single unitary value of 2.4kcal/g is applied, whereas in Japan, Maltitol, for example, is given a value of 2kcal/g and in the USA a marginally higher value of 2.1kcal/g is applied. This results in a calorie saving of up to 50%.
（2）Safe for Diabetics
Polyols are low glycaemic sweeteners and are metabolised by the body independently of insulin. They do not cause the sharp increase in blood sugar levels which usually follows the consumption of sugar or glucose and their slow absorption is seen as an advantage. Therefore, crystalline Maltitol and Polyols in general are suitable for diabetics as well as the broader population interested in diet and a healthier lifestyle.
（3）Does not cause tooth decay
Polyols do not promote tooth decay because they are resistant to metabolism by the harmful acidogenic oral bacteria. These bacteria, including Streptococcus Mutans and Lactobacilli, breakdown sugars and consequently excrete the organic acids that lead to demineralisation of the tooth enamel and ultimately tooth decay.
In common with other low digestible carbohydrates and fibres, Polyols can cause gastro-intestinal discomfort. The dosage required to produce this effect varies by Polyol and person by person, by body weight, by speed of consumption and by individual sensitivity. Regular consumption leads to increased tolerance. Generally larger doses of Maltitol can be consumed than most other Polyols. In many cases national or regional regulatory bodies have implemented guidelines that control use and labelling. For instance, in the EU, if a final product contains more than 10% by weight Polyols then a laxative warning lable is required on product packaging.