Amidst the peak mango season and the constant endeavour of cultivators and consumers to ensure a longer shelf life for the ‘king of fruits’, new research has suggested that the combined application of hot water and salicylic acid can preserve post-harvest quality.
Mango fruits undergo various biochemical changes and ripen rapidly after harvest. The integration of salicylic acid with hot water is an effective strategy for delaying ripening and preserving the post-harvest biochemical quality of mango fruits under ambient conditions, the study found. Salicylic acid is an organic compound that is widely used in skin care, as a food preservative, for regulating plant growth and in the pharmaceutical industry.
During the study, physiologically mature fruits were subjected to different levels of treatments involving salicylic acid and hot water. “Compared with untreated fruits, the combined treatments significantly reduced weight loss, decay incidence, electrolyte leakage, reactive oxygen species accumulation and activities of fruit softening enzymes, while better maintaining fruit firmness, soluble solids content, titratable acidity and ascorbic acid during storage,” the study said.
Undertaken by six researchers from the Integral Institute of Agricultural Science and Technology, Integral University, Lucknow, the study was published by Scientific Reports, a peer reviewed international journal, on June 7.
The Dashehari variety was selected for the study due to its high economic importance in northern India and its widespread cultivation in domestic supply chains, as well as the variety’s high perishability and physiological sensitivity.
Mango is one of the most widely cultivated and economically significant tropical fruits due to its high nutritional value, rich sensory attributes and extensive varietal diversity. India occupies a leading position in global mango production, with cultivation spread across approximately 2,698 thousand hectares and an annual production exceeding 26,236,000 metric tons, thereby contributing substantially to the world mango supply.
It is a climacteric fruit that ripens rapidly after harvest due to a rapid increase in the production of ethylene, a natural plant hormone that triggers ripening, and respiratory activity at room temperature. Under ambient conditions, elevated temperature further accelerates respiration, ethylene production, and oxidative stress, leading to faster deterioration compared with cold storage systems. These physiological changes substantially impact post-harvest shelf life, the researchers observed.
The ripening process involves extensive physic-chemical modifications and metabolic changes, which collectively increase susceptibility to microbial infection and post-harvest decay. Fruit softening, resulting from starch conversion, breakdown of cell wall components and oxidation, critically affects mango marketability and hence shelf life and modulating oxidative stress is essential.
Post-harvest application of salicylic acid delays ripening in mango by enhancing the antioxidant defenses, reducing oxidative damage, maintaining firmness and ascorbic acid content. Moreover, salicylic acid effectively reduces ethylene production and inhibits the activity of cell-wall degrading enzymes, thereby slowing fruit softening and membrane degradation, the researchers said.
Hot water treatment is an established, safe and eco-friendly post-harvest technique used to control decay and maintain quality in fresh produce. The method involves exposing fruits to carefully regulated temperatures ranging from 40 to 55 degrees Celsius for specific durations. It suppresses fungal pathogens and insects, reduces respiration rate, weight loss and delays deterioration during storage, according to the researchers.