Our biorefinery

Our biorefinery in Rotterdam processes raw materials, mainly corn from Europe, into a number of high-quality products. The overview below makes clear which products these are.

Sugar and protein

The process uses the starch (in fact sugar) in the corn. These sugars are converted into liquid energy: alcohol. The protein in the grain is maximally conserved and supplemented with valuable yeast proteins. These proteins thus become a highly nutritious animal feed.

The most important, most nutritious part of the grain therefore remains in the food chain.


All important steps are listed and explained in more detail in the overview.

As starch cannot ferment on its own, preparatory steps are needed. Corn is first ground, then mixed with water, boiled and then special enzymes are added. The ‘porridge’ produced after cooling goes to a fermenter where yeast and other enzymes are added. During fermentation, the yeast converts the sugars into ethanol and CO2.

The fermentation cycle lasts 50 to 60 hours at a temperature of 30 to 32°C. The resulting product, called ‘beer’, has an alcohol content of 16 to 18% by volume.

From fermentation via distillation to dehydration

This is followed by the distillation process to concentrate and purify the flow of alcohol.

The final stage of the process is dehydration, in which the remaining water is removed to produce ethanol containing less than 0,2 % water. We also call this “neutral” or “anhydrous” alcohol with a strength of 98.8%.

The animal feed

DDGS (Dried Distillers Grains with Solubles) is our main by-product. It contains about three times as much protein as the grain used. It is sold as pellets – brand name Proticorn – to the animal feed industry (dairy and beef cows, pigs and poultry).

And then there is corn oil

During the evaporation of the thin (residual) stream, after pre-treatment, the corn oil is separated using a centrifuge.

In this way you can see what is extracted from that one kernel of corn.

It is an perfect circular process.