Hi Tracy Henry.
Yes, you can reduce the amount of sourdough starter for home use without affecting the results, as long as you maintain the proper proportions and handle it correctly. The key to keeping it strong is to feed it regularly and maintain optimal conditions (temperature, timing, and feeding frequency).
For panettone sourdough, the typical proportions are:
1 part active starter
2 parts flour
1 part water
Your example of 100 g of flour, 50 g of starter, and 50 g of water works perfectly to keep it strong at a home scale.
▪️Keep in mind:
If you plan to use it for panettone, it’s crucial to maintain its strength and control the acidity. It’s recommended to refresh it 2 or 3 times a day as you approach the baking phase to ensure its vitality.
Always make sure it is well-fermented and has a slightly sweet and milky aroma, not acidic.
This approach will allow you to maintain an active starter without wasting large amounts of flour.
I hope this information is helpful.
Best regards!