Effect of conventional and organic fertilizers on volatile compounds of raspberry fruit

Abstract

Raspberries are widely consumed; the taste of these is determined by the interaction between sugars, organic acids and a set of volatile compounds. Meanwhile, organic agriculture has developed rapidly as an alternative to conventional system, and has been driven by the demand for pesticide-free food that brings greater benefits to human health. However, this system can alter the integral quality of the fruit, including the aroma, which has been little studied. Therefore, the objective of this study was to evaluate the effect of the application of organic and conventional fertilizers, in the presence of volatile compounds synthesized in the cv. 'Heritage' raspberry, during two crop cycles. The qualitative profile of volatile compounds was analysed by mass gas chromatography, obtaining as a result that fertilization treatments significantly affected the emission of volatile compounds in the most abundant functional group (C13 norisoprenoids) 48.5 vs. 25.8% and 56.9 vs. 29.1% in conventional and organic, in 2017 and 2018, respectively (p ≤ 0.05). The crop cycle affected the concentration of aldehydes (11.2 vs. 30.6% in organic, in 2017 and 2018, respectively (p ≤ 0.05). Impact compounds such as α-ionone (13.92 vs. 9.08% and 25.34 vs. 9.17% in conventional and organic in 2017 and 2018, respectively) and β-ionone (24.93 vs. 14.10% and 22.66 vs. 15.94% in conventional and organic in 2017 and 2018, respectively), presented greater abundance in conventional fertilization (p ≤ 0.05). Since there were changes in the volatile compounds, it is recommended to study whether the consumer perceives these changes.