SummaryInfluences of sodium tripolyphosphate (STPP) contents (0.1, 0.2, 0.3 and 0.4%) on water holding capacity (WHC) and texture properties of low‐salt (1.2% NaCl) single‐step high‐pressure processed chicken breast sausages (LSSS‐HPP sausages) were evaluated. Results showed that WHC was improved (4–5%) by the addition of STPP. However, the STPP contents customarily used for cooked sausages (0.3–0.5%) were excessive for LSSS‐HPP sausages, causing a soft and tacky texture. Sausages containing 0.1% of STPP had the best taste according to the sensory evaluations. Chemical interactions plus Raman spectroscopic analysis revealed that STPP addition partly changed native structures of myofibrillar proteins. Furthermore, higher STPP contents in the meat batter prevented those proteins from high pressure denaturing and aggregating in the subsequent single‐step HPP procedure. Increased hydrogen bonds and decreased hydrophobic interactions explained the better WHC and softer texture. Therefore, 0.1% of STPP is the optimal content in the processing of new‐type LSSS‐HPP sausages.