| If you mix together pure white sugar with pure yeast and water not a lot will happen. Like any living organism yeast needs nutrients to be able to work.
The important nutrients that yeast cells need in order to ferment are nitrogen, phosphate, sulphate and potassium. These nutrients are present in abundance in natural sugar sources such as molasses and grain and traditionally products such as yeast extract (dead yeast cells) are also added to fermentation systems to provide these nutrients.
Using molasses, grain, yeast extract, blood products etc in a fermentation system is fine if you have sophisticated distillation/rectification equipment which can separate pure ethanol from all these unwanted flavour and aroma compounds. But if you have a simple distillation setup then these unwanted compounds will be carried across during distillation making it impossible to produce high quality clean pure alcohol.
SPL recognises that the majority of distillation apparatus around the world is simple in construction but that companies owning such equipment would still like to be able to produce clean pure ethanol – light in character and free from off-flavours and aromas.
Achieving this requires the following;