Inorganic pyrophosphate (PPi) is considered as a diagnostic marker for various diseases such as cancer and vascular calcification. PPi also plays an important preservative role as an additive E450 in foodstuff. In this work, a selective FeIII–salen‐based probe for PPi is described; this probe disassembles in the presence of the target analyte into its molecular blocks, 1,2‐propanediamine and 3‐chloro‐5‐formyl‐4‐hydroxybenzenesulfonic acid. The latter signaling unit leads to a fluorometric response. Compared with a related prototype, the new complex shows a 2.3‐times stronger emission at 500 nm and a 155‐times better selectivity of PPi over adenosine triphosphate (ATP). Importantly, the new probe was successfully applied for detecting E450 in foodstuff.