Sorbitol – from seeds to Eureba

Sorbitol is nat­u­ral­ly found in sev­er­al fruits but is pro­duced indus­tri­al­ly from wheat and oth­er starchy crops. Thus, one of the world’s most com­mon crops becomes one of the world’s most com­mon sweet­en­ers. But how?

From glucose to sorbitol

Sorbitol is a sug­ar alco­hol. This means that the chem­i­cal struc­ture is the same as a sug­ar type, except for two hydro­gen atoms that have been attached on an oxy­gen atom.

This is done with hydro­gena­tion, which means that the sug­ar is exposed to hydro­gen, and often also pres­sure, in the pres­ence of a met­al that acts as a cat­a­lyst. Usually, it’s a nick­el alloy. The met­al becomes a land­ing place where a sug­ar mol­e­cule and a hydro­gen mol­e­cule can set­tle before they com­bine and become sug­ar alco­hol. None of the met­al is included.

The sug­ar, which in this way is con­vert­ed to sor­bitol, is glucose.

It starts with starch

Glucose is in turn pro­duced by hydrol­y­sis of starch. The starch is dis­solved in water, acid or enzymes are added, and the mix­ture is heat­ed. It caus­es the starch, which is chains of hun­dreds of glu­cose mol­e­cules, to be bro­ken up into small­er chains, that are bro­ken up into even small­er ones, and so on until one gets glu­cose syrup that most­ly con­sists of just glucose.

The starch that every­thing starts with can be from pota­toes, corn, cas­sa­va – or wheat.

Wheat

Wheat can be grown with good yields in large parts of the world, as it is durable and thrives in every­thing from a few degrees above zero, to a com­fort­able 32 degrees Celcius. However, wheat thrives best when it is around 20 degrees. The cul­ti­va­tion takes place in clay soil, prefer­ably chalky ditto.

There are many types of wheat, but bread wheat (Triticum aes­tivum) con­sti­tutes about 95 per cent of all wheat grown. Depending on whether the wheat is sown in the fall or spring it is called autumn wheat and spring wheat, respec­tive­ly.

Autumn wheat is sown in mid-September. Then it has time to ger­mi­nate and estab­lish a root sys­tem before the frost strikes. Coldness caus­es the sprout to go into hiber­na­tion. It will not con­tin­ue to grow until the spring sun warms the ground. Autumn wheat is har­vest­ed from mid-May. Spring wheat is plant­ed in spring and har­vest­ed in the fall.

Wheat is the sec­ond most cul­ti­vat­ed crop in the world, beat­en only by corn. Most wheat is cul­ti­vat­ed in China, India, and Russia. On the oth­er hand, the European Union tak­en togeth­er is at the top with 150–160 mil­lion tonnes per year.

And some of it is used to pro­duce sorbitol.

Sweet from sour berries

Sorbitol is not only pro­duced by starch from wheat and oth­er crops.; it is also pro­duced in your body. It hap­pens when an enzyme called aldose reduc­tase con­verts glu­cose into sor­bitol in your tis­sues. The enzyme is found a bit here and there in the body, includ­ing the liv­er, kid­neys and red blood cells, but also in the ovaries and the sem­i­nal vesicle.

Sorbitol is also found in fruits and berries, such as plums, pears, peach­es, apples, nec­tarines, apri­cots, straw­ber­ries, rasp­ber­ries, black­ber­ries, cher­ries – and rowan berries.

In fact, it was in the juice of rowan berries that the sweet sub­stance was dis­cov­ered. Therefore, sor­bitol got its name from the sci­en­tif­ic name for rowan berries – Sorbus aucu­paria.

Sorbitol was dis­cov­ered in 1872 by the French chemist Jean-Baptist Boussingault. However, it took more than half a cen­tu­ry before it began to be used in food.

Initially, the vol­umes were small, and it was used to replace sug­ars in foods for peo­ple with dia­betes. Compared to reg­u­lar sug­ar, sor­bitol has only a min­i­mal effect on blood sug­ar. The gly­caemic index (GI) of sor­bitol is 6 com­pared to sug­ar which has 92 if white bread is used as ref­er­ence (GI 100).

It was not until the mid-1950s that sor­bitol began to be pro­duced in larg­er quan­ti­ties. By then, sor­bitol had start­ed to be used as a mois­ture-bind­ing ingre­di­ent in skin­care and cos­met­ics prod­ucts, and as a sug­ar sub­sti­tute in sweets. Areas of use that are still stand­ing today.

Popular despite issues

Sorbitol is cheap. It is the most afford­able sug­ar alco­hol on the mar­ket. Therefore, it is also pop­u­lar as an alter­na­tive to sug­ar. But it has its issues as such.

Sorbitol is not calo­rie-free – but 2.4 kcal/​gram is sig­nif­i­cant­ly less than the 4 kcal/​gram of sug­ar. On the oth­er hand, sor­bitol is not as sweet as sug­ar. It has 50–60 per cent of the sweet­ness of reg­u­lar sug­ar. Therefore, the same sweet­ness requires twice as much sor­bitol com­pared to sug­ar, and then we have about the same calo­ries. But that’s not the worst…

Like all sug­ar alco­hols, sor­bitol has a lax­a­tive effect. How much you can eat per kilo­gram of body weight before it is time to run to the toi­let varies between dif­fer­ent sug­ar alco­hols. Best in the class is ery­thri­tol. During one day, you can safe­ly eat 0.66 grams per kilo­gram of body weight. Worst in class is… You guessed it: sor­bitol. During one day, you should not con­sume more than 0.17 grams per kilo of body weight.

Sorbitol has its place

Sorbitol also has good sides. Among oth­er things, it can serve as an excip­i­ent, and as a humec­tant in food. Besides, it has a smooth, albeit chilly, taste that suits, among oth­er things, chew­ing gum, throat tablets, can­dies, ice cream, frozen desserts and cookies.

Therefore, after all, it can be used to replace sug­ar, but rarely alone. It needs to be com­bined with oth­er ingre­di­ents that also help to fill the space of sug­ar – both lit­er­al­ly and figuratively.

The ques­tion is what the oth­er ingre­di­ents are and in what pro­por­tions they should be used. Also, new ingre­di­ents pose new chal­lenges in man­u­fac­tur­ing. Don’t wor­ry: use sweet­ened fibres.

Try sweetened fibres

Sweetened fibres is a homo­ge­neous com­po­si­tion of dietary fibres and plant-based sweet­en­ers. It is a turnkey solu­tion for food man­u­fac­tur­ers who want to reduce or alto­geth­er avoid added sug­ar, but can­not afford the time and cost need­ed to devel­op a whole new recipe with new and per­haps unfa­mil­iar ingre­di­ents like sorbitol.

If you want to try sweet­ened fibre in your recipe or for­mu­la, we can send you a sam­ple of our brand EUREBA®. Call us on tele­phone num­ber 08-613 28 88 or send an e-mail to info@​bayn.​se. You can too read more about them and down­load prod­uct sheets.