Flaxseed meal, rich in water-soluble gums, improves the texture of gluten-free (GF) products. Bioactive antioxidant peptides from flaxseed, known as linusorbs (LOs) or cyclolinopeptides, may provide health benefits. However, the stability of flaxseed-derived LOs during dough preparation, baking, and storage remains unclear. To investigate this, GF bread dough and bread were prepared with flaxseed meal, and the LO content was determined in the flaxseed meal, the bread flour with the flaxseed meal, the dough, and the bread. The LO levels were also monitored during storage at various temperatures (-18 °C, 4 °C, and 22-23 °C) for 0, 1, 2, and 4 weeks using high-performance liquid chromatography-diode array detection (HPLC-DAD). The levels of oxidized LOs, such as [1-9-NαC],[1-(