Pour wort in the Mason jar and take the hydrometer reading. I typically aim for 1.055 S.G. but based on the desired alcoholic strength of the beer, we may add or reduce the malt.
(Optional): Oxygenation of the wort is more important in larger batches. In smaller batches (less than 10 liters), pouring from a height is sufficient to infuse oxygen back. Use a hand blender (or) manually shake the wort vigorously to oxygenate. Compressed air is pumped in commercial breweries to increase the oxygen levels.
Hydrate the yeast in 10 parts of water (10ml per liter) and add yeast nutrients. Mix them well and wait for about 15 minutes. If yeast is alive, we should see the yeast foam (bubbles) being formed. This is the most crucial step and dead/ inactive yeast can ruin any batch.
Seal the lid and attach the airlock. It should start bubbling in 4-12 hours. (Diagnostics): Press the plastic lid gently to induce bubbling. If there is a leakage in the seal, the airlock will not bubble and one can add a sealant in the gap.
Store it away from sunlight in a cool dark place and check specific gravity periodically over next 7 days or until bubbling has stopped.
Please take the hydrometer/ refractometer reading. You can refer the original & final gravity in a Plato table (Percentage of malt in the solution). This will help measure the alcohol content.
Not all beer styles are supposed to be clear. If we prefer clarity, keep the fermenter at 4oC for 48 hours for turbidity to settle down. Dissolving 1/4 a teaspoon of gelatin in ½ a cup of warm water (not boiling) and mixing it with the beer will aid in suspended yeast settling down. It takes 48-72 hours for the process to show results. You will get a thick yellow yeast cake at the bottom and a clear beer.