What Is Refined Flour?
The Definition
Refined Flour (often labelled as White Bread Flour) has had the bran and germ mechanically removed, leaving only the starchy endosperm. While this creates a flour that produces high volume and airy bread (due to strong, uninterrupted gluten), it is a biological "desert."
The Deficit
Refined flour lacks the minerals (ash) and vitamins required for optimal bacterial health. To maintain a healthy starter on refined flour, it is often necessary to "spike" the feed with a portion of whole grain (rye or wheat) to prevent the culture from becoming sluggish.
Last updated: 6 January, 2026
Phytic acid is a natural substance found in plant seeds, nuts, and grains, and serves as the plant's principal storage form of phosphorus. In human nutrition, it is often termed an "anti-nutrient" because it acts as a strong chelator.