During the fermentation process, the cut grass is chopped into even smaller pieces (0.5 inches or 1.3 cms) and then compressed to eject the oxygen more efficiently.

This is important because the microorganisms especially, lactic acid bacteria, grow best under anaerobic (oxygen-free) conditions.

When oxygen remains, plant enzymes and other bacteria react with the plant sugars and proteins to make energy, thus reducing the amount of nutrients in the final product.