Why does fermentatin have to be enclosed in a fermenter under airlock?
1. Yeast needs to have a controlled access to oxygen. During the first stage of fermentation (aerobic) oxygen is used by the yeast to multiply. The second stage (anaerobic) takes place when the oxygen is exhausted and the yeast looks to the sugar for it’s food source. It then stops multiplying and starts producing alcohol and Carbon Dioxide. 2. With all forms of fermentation we are producing a sweet mix with good nutrients suitable for a very wide range of organisms to thrive. We then introduce the organisim that we want to multipy ie. yeast. It is important to restrict access to other organisms by sanitising everything and keeping the mix sealed in an air tight fermenter. Regardless of how careful you are with your sanitising, some bacteria and unwanted organisms will make their way into your mix. Yeast multiply approx every 2 hours and bacteria every 20 minutes however when yeasts start to multiply they reduce the ph (increase acidity) and remove the oxygen. Both of these factors wil
