Sensory perception of citrate and malate and their impact on the overall taste in apricot (Prunus armeniaca L.) fruits

Understanding the relationship between composition and taste is of pivotal importance for fruit quality improvement. This study aims to shed a light on the complex relationship between apricot fruit composition (both flesh and skin) and sensory perception. For this purpose, a total of 23 between apricot cultivars and breeding selections were characterized for a range of fruit-quality-related traits (maturity date, fresh weight, flesh firmness, soluble solids content, titratable acidity and total polyphenols content) and ten organic acids pattern in both flesh and skin. Fruit analytical data were correlated to sensory intensity through a detailed evaluation performed by ten trained panelists', with a particular focus on the impact of malate and citrate content on taste and acidity perception. Malate and citrate account for the 95% of the whole organic acids, although their content and ratio widely varied across the evaluated accessions (range of 0.96 - 14.05 and 0.33 - 20.08, respectively). Sweet-sour taste perception was greatly predicted by soluble solids content in apricots flesh (correlation of 0.60), but even more affected by titratable acidity (correlation between-0.84 and-0.97). In turn, titratable acidity was the main responsible of sour taste (correlation of 0.76) where citrate taste intensity (correlation up to 0.42) was stronger than malate in both fruit flesh and skin, with a negative effect on eating pleasantness. Results confirmed the importance of combining objective and sensory analyses to adequately comprehend apricot fruit quality. Moreover, the results corroborated the complexity of features defining the apricot fruit taste. This study provides novel insights into fruit quality-criteria to be considered in both breeding purposes and consumer's satisfaction-driven selection procedures.