Effect of salicylic acid on quality attributes, phenolic and organic acid stability in ‘Angeleno’ plums during cold storage

Abstract Background In the present research, plum fruits were subjected to pre-storage treatments with salicylic acid at concentrations of 0.5, 1.0, and 1.5 mM, followed by storage durations of 15, 30, 45 days. A control group, without any treatment, was stored under the same conditions. Throughout storage, various parameters including weight loss, fruit firmness, decay and respiration rate, soluble solids content (SSC), titratable acidity (TA), pH, phenolic compounds, organic acids, vitamin C levels were evaluated. Results Findings revealed that untreated fruits exhibited greater increases in weight loss, SSC, pH, decay, and respiration rates, along with a marked decrease in firmness over time compared to the salicylic acid-treated groups. The TA values in salicylic acid-treated fruits demonstrated variation dependent on the storage interval. In this study, 1.0 mM and 1.5 mM salicylic acid applications were more prominent in terms of physical properties. In the 1.0 mM salicylic acid application, lower weight loss (45th day: 3.60%), decay (45th day: 6.44%), and respiration (45th day: 43.12 mg CO2 kg−1 h−1) rates, and higher fruit firmness (45th day: 31.76) were observed compared to control fruits. Among the treated groups, fruits treated with 1.5 mM salicylic acid retained higher levels of phenolic compounds and organic acids. Moreover, all salicylic acid treatments were effective in preserving vitamin C better than the control. The most prevalent organic acid identified in plums was malic acid (45th day: 258.73 mg 100 g−1), with citric (45th day: 31.01 mg 100 g−1) and succinic (45th day: 26.88 mg 100 g−1) acids following in concentration. Chlorogenic acid (45th day: 8.65 mg 100 g−1) was the predominant phenolic compound, with gallic acid (45th day: 3.62 mg 100 g−1) and p-coumaric acid (45th day: 2.85 mg 100 g−1) ranking next. Conclusions Overall, the 1.5 mM salicylic acid treatment showed the greatest efficacy in maintaining quality attributes during storage. In 1.5 mM salicylic acid application, fruit firmness increased by 20.15% and weight loss and respiration rate decreased by 54.44% and 39.93%, respectively, compared to control group fruits after 45 days of storage.