GB1474177A - Concentration of volatiles-bearing products - Google Patents

Abstract

1474177 Multi-stage evaporation A P V CO Ltd 24 July 1974 [30 July 1973] 36189/73 Heading B1B Volatiles-bearing products e.g. fruit juices are concentrated by low temperature, multistage, multi-effect evaporation with a forward feed of product and vapour so that at least from a given stage of evaporation each subsequent stage is carried out at a lower temperature in which the volatile constituents, removed with the vapour from one or more effects and subsequently condensed and recovered, are combined with the partially concentrated product before a final stage or stages of evaporation at a temperature lower than that at which they were originally distilled off whereby a more highly volatile fraction is removed with the vapour in the final stage or stages of evaporation. The Fig. shows juices fed to the second effect B which is at a lower temperature than first effect A, the water vapour and aroma being fed to the third effect divided into two stages C and D, and the remaining liquid juice fed back to A where it is subjected to the highest temperature and thence to stage C and finally to D where concentration is completed. Volatilerich vapour fed to the third effect is partially condensed in C and D and is passed with uncondensed vapour to recovery unit E. Recovered aroma is pumped from E to mixing chamber F where it is mixed with partially concentrated product from C prior to feeding to final stage D where some volatiles e.g. those in the oil fraction are removed with the vapour.