Comparing the Effects of High Hydrostatic Pressure and Thermal Processing on Blanched and Unblanched Mango (Mangifera indica L.) Nectar: Using Headspace Fingerprinting as an Untargeted Approach

The effects of high hydrostatic pressure and thermal processing on blanched and unblanched mango nectar were addressed by headspace GC-MS fingerprinting as an untargeted approach. Comparison between high hydrostatic pressure and thermal processing was performed based on the principle of equivalence. A considerable number of volatiles with higher concentrations were observed in unblanched mango nectar compared to blanched mango nectar. Both for high hydrostatic pressure and thermal processing, changes of mango nectar volatiles (composition and concentration) became more pronounced upon increasing processing intensity. However, based on a fair comparison, different process-induced chemical changes were detected for high hydrostatic pressure and thermal processing. For unblanched mango nectar, thermal processing seems to favor the formation of sulfur-containing compounds (dimethyl sulfide), whereas high hydrostatic pressure seems to enhance the oxidation of free fatty acids, leading to increased concentration of aldehyde and alcohol volatile compounds (1-penten-3-ol, (Z)-2-penten-1-ol, and (E)-2-pentenal) in mango nectar. For blanched mango nectar, less significant differences were found between high hydrostatic pressure and thermal processing. This work demonstrates that different processing steps, for example blanching, high hydrostatic pressure, and thermal processing, have influence on the volatile profiles of the processed products.