Starch Institute


Starch Technology

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Sorbitol is a , C6H14O6 Hydrogenated starch hydrolysates found in nature as the sweet constituent (HSH), - polyglycitol syrups - are found in of many berries and fruits – best known a variety of . They serve as bulk from Sorbus aucuparia (Rowan or sweeteners, or bodying agents, European Rowan) from which it was moisture retaining ingredients, crystalliza- isolated for the first time in 1872. tion modifiers etc. – just like sorbitol.

Mid 1950’s, sorbitol large scale HSH and sorbitol are made the same manufacture began due to new way, but from starch hydrolysates of applications, such as in different Dextrose Equivalent (DE) and cosmetology and in non different composition. cariogenic . Sorbitol is the result of of Sorbitol is today commercially produced dextrose or starch syrup with a high DE from starch by enzymatic and equivalent to pure dextrose, while a catalytic hydrogenation. It has wide appli- hydrogenation of low DE hydrolysate will cations as a sweetener and humectant. lead to a mixture of sorbitol, , and longer chain hydrogenated saccharides (maltitritol a.o.) With no single dominant the generic name “Hydrogenated Starch Hydrolysate” is used. If 50% or Sorbitol more of the are of one type, it can C6H14O6 182.17 g mol−1 be labelled as "Sorbitol syrup", or "Maltitol syrup", etc. A special variety is

manufactured by hydrogenation of the mother liqueur (hydrol) after first dextrose CRYSTALLINE PROPERTIES monohydrate crystallization.

Hydrogenated starch hydrolysates are 20% Sorbitol has four crystal structures - four to 50% as sweet as sugar depending on its anhydrous crystalline phases plus the particular composition. hydrate. It may be crystallized from an or low moisture melt or The HSH family of polyols is an approved even spray dried / spray crystallized. ingredient in most countries. U.S. Gamma polymorph is the most stable of food manufacturers may use HSH while the anhydrous crystalline forms FDA reviews the petition seeking confirmed by its high and approval for its use in foods. low hygroscopicity and is the only form of significance for the confectionery and SYNONYMS pharmaceutical industries. • Sorbitol Density 1.489 g/cm³ • Glucitol Melting point 95 °C • D-glucitol point 296 °C • D-Sorbitol • Sorbite • Hydrogenated Starch Hydrolysate (HSH)

Copyright © 2009 International Starch Institute, Science Park Aarhus, Denmark. Copyright © 2009 International Starch Institute,Rowan Science Tree, Park Aarhus, Sorbus Denmark. aucuparia Sorbitol is the sweet constituent of the berries.

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Starch crops – grain or roots – are the The front end design depends on the basic raw materials. selected agro commodity. The attached diagram shows briefly the process route. Also purified starch of any origin – corn, The various designs are described in , potato or cassava – can be used. greater detail in respective Technical Memorand a. The hydrogenation can of course begin with dextrose – or dry – but in real The basic raw materials are cleaned and the process begins with basic raw the starch is extracted in a wet milling materials like cassava, corn or wheat. process and then concentrated and purified. So far the process is identical to the one used for the manufacturing of native starch as the end product.

Multi stage starch extractors.

Being a tropical crop cassava can be Instead of drying the starch, the grown and harvested round the year, concentrated pure starch milk is liquefied which is a great advantage. This makes by cooking with or alpha-amylase. cassava a cheap source for The cooking is carried out continuously in the manufacture of starch sugar and a converter by injecting steam. downstream products like starch sugar . A rather low DE hydrolysate is the resulting intermediate of this conversion. The hydrolysate is then hydrolyzed to the very end as the dextrose and purified.

The purified fully saccharified starch solution is concentrated and is now identical to standard high DE dextrose syrup.

Hydrogenation in progress

Copyright © 2009 International Starch Institute, Science Park Aarhus, Denmark.

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The clear high purity dextrose solution is hydrogenated in the presence of a Process Route catalyst in vigorously stirred reactors at specified pressure and temperature. It is Reception of (1) Starch ► necessary to safe-guard the process crop grain or roots carefully, because of the ▼ Cleaning of grain ► ► Waste applied. Head space of the autoclave is or roots initially flushed with to remove ▼ Disintegrating and air and its completely. Hydrogen is made on site. The hydrogenation is wet milling carried out intermittently in few hours’ ▼ Starch ► Byproducts cycles. The hydrogenated solution is Extraction decanted and subsequently subjected to ▼ Starch treatment and . The catalyst is recycled and reused. Concentration ▼ Starch

Refining ▼ Starch (2) Native ► starch Liquefaction ▼ Hydrolysate

Saccharification ▼ Dextrose

Purification ▼ Dextrose

Concentration ▼ Dextrose (3) Glu- ► cose syrup preparation ▼ Hydrogen ► Dextrose

Catalyst ► Hydrogenation ▼ Sorbitol

Purification ▼ Sorbitol Sorbitol ► Syrup condenser Concentration 70% ▼ Sorbitol Sorbitol ► Solidification powder The purified solution is evaporated to 70% dry matter - the most usual Input to the process may be either concentration of Liquid Sorbitol. The (1) a starchy crop like cassava, corn and wheat, syrup may be spray dried or crystallized (2) a native starch of any origin or to obtain a powder. (3) pure dextrose monohydrate or syrup of a suitable DE dependent on sorbitol specifications.

Copyright © 2009 International Starch Institute, Science Park Aarhus, Denmark.

Danish factory for the manufacture of D-sorbitol and L-ascorbic acid.

D-sorbitol is obtained by catalytic reduction of D-glucose. By means of gluconobacter

oxydans D-sorbitol is oxidized to L-sorbose, which is a necessary intermediate in the process for L-ascorbic acid ( C). Copyright © 2009 International Starch Institute, Science Park Aarhus, Denmark.

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SUGAR ALCOHOL MARKET Sorbitol has a smooth mouth feel with a Once upon a time was the sole sweet, cool and pleasant . Sorbitol ruler on the market. This acts as a crystallization modifier or position was challenged, when sorbitol inhibitor; it can prevent syrups from half a century ago was introduced on a forming crystals of sugar. It is used to larger scale. This market has since add body and viscosity to mixtures, and undergone a major expansion in terms of can protect against damage from quantity and uses. This expansion is due () and drying. to new sugar alcohols with new and different properties and consequently Liquid sorbitol itself has a tendency to more uses. crystallize at room temperature. A product of choice for most applications is One important use is replacement of non-crystallizing sorbitol (NCS) - a 70% traditional table sugar (). Sugar solution with approximately 50% sorbitol alcohols (polyols) are all low-caloric, and smaller amounts of other polyols sugar-free, alternative sweeteners. They (maltitol a.o.) are replacement for sucrose and starch syrup in low-sugar and sugar-free It shares many applications with formulations. They are qualified for and glycerine and product labelling as "Sugar Free", glycerine provides hard competition in the market for . A new fuel – bio- "Reduced Sugar" and "No Sugar Added". They provide exceptional bulk and body diesel - has glycerine as by-product and and are lower in than sucrose. will increase the output of glycerine in the future and put some polyol based glycerine replacements under pressure. Polyols are non-cariogenic. They can be used alone or in combination with other polyols and/or sweeteners. Even mixtures Global production of sorbitol has reached with glycerine are available as perfect approximately 800.000 MT per year. glycerine substitutes. Sorbitol being the most commonly used The common sugar alcohols – sorbitol, polyol (it is the least costly) held the , maltitol, , and biggest market share among similar polyols. hydrogenated starch hydrolysates – are manufactured from starch. • Sorbitol 800,000 MT SORBITOL • 200,000 MT • Mannitol 180,000 MT • Maltitol 160,000 MT

Roquette Frères is the world's biggest sorbitol producer. Together with Cargill and Corn Products Specialty Ingredients they hold a market share of over 70%.

Roquette has set up several production bases worldwide and is also constructing a large sorbitol plant in the east of China.

Copyright © 2009 International Starch Institute, Science Park Aarhus, Denmark.

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Polyols are made for the Lactitol is a non-starch Xylitol is a non-starch industrial market and hard to sweetener produced from sweetener found in straw- find in a supermarket. whey. The is isolated berries, raspberries a.o. It is and hydrogenated. Largest made by hydrogenation of In the European Union (EU) manufacturer is the Danish . This in turn is derived polyols are considered as food company Danisco. from extracted from birch additives and are given the trees or corn cobs. The Danish following E-numbers: company Danisco is the largest MALTITOL xylitol manufacturer. • 420 Sorbitol • 421 Mannitol Maltitol is made from starch by • 953 hydrogenation of high • 965 Maltitol syrup. Its high • 966 Lactitol allows it to be used without • 967 Xylitol being mixed with high intensity • 968 Erythritol sweeteners. The cooling effect is negligible in comparison w ith other sugar alcohols.

MANNITOL Starch based high syrup is hydrogenated. During hydrogenation the fructose molecule rearranges to and a mixture of The cooling sensation drops from sorbitol and mannitol is left to right. obtained. Mannitol is isolated Xylitol consumer package. and made commercially The name “BirkeSød” = “Birch- available in a variety of powder Sweet” and the trees on the label Sweetness Calories and granular forms. Mannitol is alludes to the old name " Sucrose = 1 kcal/g non-hygroscopic. sugar" from a time when Finnish Glycerol 0.6 4.3 birch trees constituted the sole HSH 0.2–0.5 3.0 raw material for xylitol. Erythritol 0.8 0.2 ERYTHRITOL Isomalt 0.5 2.0 POLYGLYCITOL Lactitol 0.4 2.0 Erythritol occurs naturally in Maltitol 0.9 2.1 fruits and fermented foods. It Polyglycitol - known as hydro- Mannitol 0.6 1.6 is produced from glucose by genated starch hydrolysate Sorbitol 0.6 2.6 with osmophilic (HSH) - denotes a whole family such as Moniliella Xylitol 1.0 2.4 of products based on starch pollini, Torula coralline a.o. It and glucose and made the is approved in the United same way as sorbitol. ISOMALT States. Erythritol was approved in the European Non-crystallising sorbitol is in Isomalt is a non-starch Union 2006. fact polyglycitol syrup. sweetener manufactured in a two-stage process. Sugar Erythritol is absorbed in the "Hydrogenated starch hydroly- (sucrose) is transformed into , and then for the sate", "Hydrogenated glucose by fermentation or most part excreted unchanged syrup" and "Maltitol syrup" are by an immobilized in the . It is absorbed names often used interchange- system and then hydrogenated before it enters the large ably and sometimes to isomalt. Isomaltulose is intestine and does not normally incorrectly. used as a sucrose substitute cause effects. itself.

Copyright © 2009 International Starch Institute, Science Park Aarhus, Denmark.

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Sorbitol, together with other polyhydric Sorbitol is a natural sweetener found in alcohols such as glycerol, is one of the many stone fruits and berries. The ingredients in resins and rigid artificial version is nature identical. foams manufacturing. A review on sorbitol safety as been In industries, sorbitol may give assessed by the Joint FAO/WHO Expert mild effect in sniff. It is an excellent Committee on Food Additives concludes humectant and develops no pungent that it is not necessary to limit the dietary odour of such as glycerine, when intake of sorbitol and related . Nor tobacco is smoked. has the Committee specified an “” for Sorbitol. In the Code of Federal Regulations, FDA notes that sorbitol is used in food at levels not to exceed good manufacturing practices.

These regulations further require that any sorbitol-containing foods whose con- sumption would add 50 grams of sorbitol to a person’s diet must be labelled with the statement, “Excess consumption may have a laxative effect.”

Sorbitol solution is sold as a hyper- Sorbitol is used as softener and colour osmotic laxative through pharmacies stabiliser in textiles and as softener in (Sorbilax). Excessive consumption can leather industries. lead to gastrointestinal discomfort.

The manufacture of consumes In USA use is regulated by FDA. A approximately 15% of world sorbitol maximum level of 99% of sorbitol may be production. Gluconobacter oxydans are used in hard and cough drops, used for the 98% in soft candy, 30% in commercial oxidative con- jams and jellies, 30% in baked goods version of D- and baking mixes, 17% in frozen dairy sorbitol to L- desserts and mixes and 12% in all other sorbose – an foods. important inter- mediate in de Uses of sorbitol in food are still a cause manufacture of for concern among the public - L-ascorbic acid particularly in children's food. It is, (Vitamin C). however, a concern sorbitol may share with other polyols and, for that matter with other chemically pure food items.

Copyright © 2009 International Starch Institute, Science Park Aarhus, Denmark.

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A possible pathway of sorbitol Sorbitol does not promote ; it is via fructose and glycogen is resistant to metabolism by oral to glucose. This process is slow. In trials which break down sugars and to no significant increase in sugar release that may lead to caries. In were observed after intake of – around 20% of the sorbitol with 35 g sorbitol. The low market - it serves as a humectant, body- explains the interest for sorbitol in ing agent, sweetener, shelf-life extender, diabetic foods. crystallization inhibitor. It competes with the sweeter xylitol, but in many recipes, they act together.

Sorbitol is an obvious choice for chewing gums and non-cariogenic confectionery. It is far better than table sugar. It adds sweetness with no risk of tooth decay.

Glycemic Index. The metabolism of polyols in the body is slow or even missing. The higher and faster the blood sugar rises after a standardized intake, the higher the score the food is given, on a scale of one to 100. The glycemic index is low for most polyols and they are therefore suitable for a diabetic diet. Oral-care is in fact an important market with toothpaste, chewing gums, mouth- Sorbitol is actually a nutritive sweetener wash and breath fresheners as top with 2.6 calories per gram. Table sugar sellers. has 4 calories per gram. Slimming foods take advantage of this difference in CARE calories and add high intensity sweeteners to compensate for the lower Sorbitol retains moisture on the skin and sweetness of sorbitol. leaves it feeling soft. Up to 5% is used in creams, , , lipsticks, masks, shaving cream, aftershave lotions, and hair conditioners. Sorbitol is also number one, when it comes to clarity and translucency as in transparent bar and translucent gels. Disclaimer. The information contained in this publication is to the best of our knowledge reliable. Users should, however, conduct their own tests to determine the suitability of our products and recommendations for their own specific purposes. Statements contained herein should not be considered as a warranty of any kind, expressed or implied, and no liability is accepted for the infringement of any patents.

Copyright © 2009 International Starch Institute, Science Park Aarhus, Denmark.

... a member of the International Starch Group

International Starch Institute, Science Park Aarhus, Gustav Wieds Vej 10, DK-8000 Aarhus C, Denmark. Phone: +45 8620 2000. Telefax: +45 8730 0223. [email protected] www.starch.dk