Salicylic acid and nutrient immersion to maintain apple quality and bioactive compounds in postharvest

Abstract

The world production of apples in the 2019 cycle reached 7´620,288 tonnes. For marketing purposes and to supply the demand, apple fruits need to be stored for different periods under refrigerated conditions. However, in the market, the shelf life of the fruit is short, the quality decreases in postharvest due to the dynamic changes of its physicochemical properties, which cannot be stopped, but can be slowed down to improve its shelf life. Postharvest treatments by immersing apple fruit in salicylic acid (SA) and nutrients are an innovative technological alternative to maintain their quality. In this study, 5 concentrations were tested for the immersion of apple fruits cv ‘Golden Delicious’, using a 56 factorial arrangement delimited to 25 treatments, using the Taguchi L25 structure: SA 0 - 1.440 mM, potassium (K) 0 - 2.250, calcium (Ca) 0 - 31.500 mM, cobalt (Co) 0 - 0.180 mM, molybdenum (Mo) 0 - 0.0900 mM and magnesium (Mg) 0 - 0.0900 mM. The study was conducted in the municipality of Cuauhtémoc, Chihuahua, Mexico. After 7 months of storage and 13 days of shelf life, the combination of K, Ca, SA and Co with the appropriate concentration values can maintain the quality variables and bioactive compounds at the desired optimum. It is concluded that the quality variables; firmness, juice percentage, juice density, titratable acidity and total soluble solids and the bioactive compounds; total phenols and antioxidant capacity can be maintained at the desired optimum.