In general, cold break process resulted in higher levels of discriminative volatiles compared to hot break. This observation might be attributed to one or more of the following factors: (i) enzyme activity (only in case of tomato); (ii) heating of a different starting material (pieces versus puree), which might result in a different heat transfer; (iii) different structure; and (iv) interaction between precursors from different matrices.
By comparing the volatile fraction of a mixed system produced by an all-in-one process versus a split-stream process, not so many differences were found indicating that process step does not have a big impact on the volatile profile. GC–MS based untargeted profiling or fingerprinting analysis showed that the difference of volatile profiles due to combined vis-à-vis individual processing (i.e. how to process) was much less compared to that between hot break versus cold break (i.e. what type of process). Studying the effect of HB and CB on a single ingredient of a mixed vegetable puree showed that changing processing condition of carrot had greater impact than that of tomato, since more discriminant compounds were selected when carrot was processed in a different way.