How to cultivate naturally occurring wild yeast and lactic acid bacteria to use for baking bread.

Ingredients:

Equipment:

Execution:

day 1 - 7:

To start, weigh your jar and keep a record of its weight as this will serve as your guide for future measurements when discarding the starter.
Next, mix 50g of whole grain flour and 50g of bread flour in a sanitized glass jar with 100 mL of filtered water. Stir the mixture thoroughly until there is no dry flour remaining. Place a loose fitting lid on top of the container and let it sit at room temperature.

day 7 and onwards.

At this point, your sourdough starter should be fully developed and teeming with yeast and lactic acid bacteria, resulting in a bubbly, active concoction. You can confirm your starter is ready to use when it rises to about double its volume and then falls predictably, usually occurring around the same time each day, provided you feed it at the same time daily. It's worth noting that every starter can vary in how it rises, due to environmental factors and differences in the amount and potency of yeast in the flour you use. Consequently, your starter may mature in as little as four days, while another person's may take up to 10 days to reach the same readiness.
Every 12-24 hours, remove enough starter to leave around 50g plus the weight of your jar, then add 50g of whole grain flour and 50g of bread flour and 100mL of water to the remaining starter. Mix the ingredients thoroughly until there is no dry flour remaining, then place a loosely fitting lid on top of the container and let it sit at room temperature.
If you bake bread frequently, you can keep your sourdough starter at room temperature and continue to follow the above instructions. However, if you don't plan on baking often, you can store your starter in the fridge and feed it every 2-4 weeks. When you're ready to use it, take the starter out of the fridge a couple of days before baking and provide it with two additional feedings to ensure it becomes fully active again.