Sugar – more than just sweet stuff

Whether as rock sugar or sugar cubes, whether hidden in gummy bears or soda: sugar sweetens our daily life. And just as diverse as the possibilities for its use in the food sector, are, from a chemical perspective, the uses for sugar itself. There is glucose (grape sugar), lactose (milk sugar), fructose (fruit sugar), and a number of other sugars, which, however, do not all taste sweet. Scientists of the vTI Institute for Agricultural Technology and Biosystems Engineering are working to prepare sugar as a natural raw material for a number of industrial purposes.

The cosmetic industry, for example, uses sugar as a self-tanning product: erythrulose – a sugar that can be biotechically manufactured from household or grape sugar. Many biological tanning products contain this substance. In a joint project with the Südzucker AG, the vTI scientist have developed a new, two stage production process – a special fungus converts the basic substance into an interim product, which is further processed by a bacteria to erythrulose. With this, in the meantime patented, bio-technical process, a significantly higher concentration and yield can be targeted as previously. For this purpose a specially adapted bacteria culture (Genus: Gluconobacter) had to be found for the production process and the basic conditions such as temperature and pH value had to be optimized.

A broader range use for sugar is developed if the sweet substance is converted into saccharic acid. We encounter the gluconic acid drawn from grape sugar regularly in our daily lives in a wide range of products. Gluconic acid was until now the only saccharic acid that could be produced on a large scale and that in bio-technical manner. At the vTI, in the meantime, an innovative chemical process was developed with which other sugars can be converted into organic acids. Catalysers from minute gold particles fixed in a carrier substance are the key to success here. In the nano range (2-5 nanometers are 2-5 millionths of a millimetre), gold possesses special chemical properties and can catalyse specific sugars very specifically and convert sugars to saccharic acids without bothersome by-products. These catalyzers are inexpensive to produce and open fully new perspectives since other sugars can be used in addition to grape sugar. The now patented process is currently being used in practice. In 2010, a demonstration facility was started up in 1000 ton level by the Südzucker AG. As a renewable resource, sugar thus faces a “golden future.”