Fruit Juices




Enzymes are used in the processing of non-citrus fruits to maximise the production of CLEAR juice.


Nearly all fruits and berries contain pectins and other polysaccharides such as starch and aribinoxylans. Pectins hold the fruit cells together like a 'glue' and result in poor liberation of juice during pulping. The presence of soluble pectins in the subsequent juice also causes hazing. The addition of pectin degrading enzymes (pectin methyl esterase, polygalacturonase and pectin lyase) at the pulping stage increases the yield of juice and helps in the clarification. Pectin degrading enzymes are particularly important in the production of fruit juice concentrates as pectins can form very viscous gels which hinder filtration and concentration to high levels of dissolved solids.


Arabinoxylan and starch hazes particularly in apple juice can also be treated by the addition of xylanases and α-amylases. Cellulases also play a role in the extraction of juice from berries where juice yield together with the extraction of colour and flavour components can be difficult.


Citrus fruit juice


Enzymes are used in the processing of these fruits to maximise the production of CLOUDY juice.


The problems of extracting juice from citrus pulp and reducing the viscosity of the juice for concentration are similar to those of non-citrus fruit processing. However, citrus juices and in particular orange juice are meant to be cloudy as much of the desired flavour and colour depends on the insoluble, cloudy materials of the pressed juice. Cloud stability is controlled by careful manipulation of the pectin component of the juice. This complex process requires a balance between pectin methyl esterase which will promote cloud formation by increasing pectin / calcium complex formation and polygalacturonase which will break cloud formation by depolymerisation of the pectin before complex formation.


Contact us for all your requirements including:

  • Enzyme activity analysis for quality control
  • New product development
  • Enzyme stabilisation
  • Raw material analysis
  • Process optimisation
  • Finished product analysis
Enzyme Services & Consultancy (ESC), Unit 6, Innovation & Technology Centre, Tredomen Park, Ystrad Mynach, CF82 7FQ
E T (0)1443 866401 F (0)1443 381800