Fermentation is Anaerobic Respiration 

To remember that fermentation is anaerobic respiration use the following mnemonic:

That fur was meant for my latest creation (fermentation) but now the anaconda has gone and wrapped the bear in rows of coils and it will be a quick (anaerobic) death. 

Fermentation is an anaerobic (non oxygen requiring) process where yeast (a single celled micro-organism) breaks down glucose (a sugar) to make ethanol (alcohol) and carbon dioxide. 

Glucose → Ethanol + Carbon Dioxide

The process is fundamental to:

• Baking where the carbon dioxide produced causes bread to rise (the ethanol evaporates during baking).

• Brewing and winemaking where the ethanol is the desired product.