Study of the compositional changes of mango during ripening by use of nuclear magnetic resonance spectroscopy.
Gil A. M., Duarte I. F., Delgadillo I., Colquhoun I. J., Casuscelli F., Humpfer E., Spraul M.
Author Affiliation: Institute of Food Research, Norwich Laboratory, Norwich Research Park, Colney, Norwich NR4 7UA, UK.
Journal of Agricultural and Food Chemistry 48 : 1524-1536
Abstract : Liquid-state NMR spectroscopy was used to follow the compositional changes in mango juice during ripening, and MAS and HR-MAS techniques enabled resolved 13C and 1H NMR spectra of mango pulps to be recorded. Spectral assignment enabled the identification of several organic acids, amino acids, and other minor components, and the compositional changes upon ripening were followed through changes in spectra. In pulps, sucrose predominated over fructose and glucose at most ripening stages, and citric acid content decreased markedly after the initial ripening stages while alanine increased significantly. Other spectral changes reflected the complex biochemistry of mango ripening and enabled the role played by some compounds to be discussed. Some differences observed between the composition of juices and pulps are discussed. This work shows that NMR spectroscopy enables the direct characterization of intact mango pulps, thus allowing the noninvasive study of the overall biochemistry in whole fruits.