This original research compared heat‑drying (HD) versus freeze‑drying (FD) of loquat flowers and their hot‑water powdered extracts using UPLC–MS/MS metabolomics and antioxidant assays. FD preserved more heat‑sensitive (thermolabile) flavonoids. For example, cyanidin was about 6.62× higher with FD, and delphinidin 3‑O‑β‑D‑sambubioside was about 49.85× higher. Heat‑drying degraded many flavonoids but increased some, such as 6‑hydroxyluteolin (~27.36×). Freeze‑dried powder (FDP) showed the highest antioxidant activity (~608.83 μg Trolox equivalents per gram) and tighter clustering in multivariate analyses, suggesting more stable metabolite profiles. Takeaway: FD is ideal when the goal is maximum bioactive retention; HD can be used when cost and heat‑stable targets are the priority. (Not medical advice.)