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Enzyme Modified Cheese

  Cheese is a major staple food of the Western World. Cheese is also an enzyme produced food. Not only  does   an enzyme turn the milk initially into the curds and whey creating the texture of cheese, but a whole range of enzymes turn the bland immature cheese curd into the wide range of cheese flavours that we have in the world today. With the exception of Italian cheeses, where their sharp flavours are produced by the addition of a pre-gastric esterase, the remaining types of flavours are generated by enzymes produced from the microflora present in the cheese. Moulds such as Penicillium produce the blue type cheeses such as Danish Blue (fatty acid flavour) and Roquefort (methyl ketones); and bacteria such as Lactobacillus produce protein notes in cheeses such as Cheddar. A different and more stable form of cheese is processed cheese. Processed cheese is exactly what it sounds, real fresh cheese processed in to a more stable form. Processed cheese was developed independently in Europe and the USA at the beginning of the last century. All types of cheese can be used to make processed cheese; but the different types will have a big impact on the final flavour. If very young immature cheese, which has almost zero flavour, is used then the processed cheese will also have almost zero flavour. The main advantage of using young cheese is that it is much cheaper than mature cheese. If young cheese is used, then to avoid a bland processed cheese product being made, additional flavour has to be added. This can be done in one of two ways; either a certain percentage of strongly flavoured mature cheese can be used or Enzyme Modified Cheese (EMC) can be used.

The main steps in processed cheese manufacture

i) Blending & shredding of the cheese

ii) Emulsification

iii) Thermal processing

iv) Homogenisation (optional)

v) Cooling & packing

  EMC is made in a similar way to processed cheese. Real cheese is taken and certain enzymes added. These enzymes are the same types that turn young flavourless cheese into strongly flavoured mature cheese; but they are added at a much higher dose rate. So rather than getting a strong cheese flavour after 1 to 2 years, EMC is produced in 1 to 2 days. EMC used to be made solely by use of pig pancreatic enzymes, but the production methods used now are much more sophisticated. 

  The main focus is on microbial and fungal enzymes as vegetarian alternatives to pancreatic lipase. Another big advantage of these enzymes over pancreatic lipase/protease is that this animal product can only ever produce one flavour profile. It can be used in different combinations to produce a wide range of different cheese flavours. Furthermore there is always a concern about possible contamination of animal products with viruses or prions. This problem does not exist with microbial & fungal enzymes.

 

 Schematic representation of Enzyme modified cheese manufacture

Off-cuts or
shredded cheese

 

 (60 to 65% dry solids)

 

 

Mix

 

             Water and emulsifing salts (optional)

 

 

Cheese Slurry

 

  (40 to 55% dry solids)

 

 

Pasteurise

 

             (72oC 10 minutes)

 

 

Cool

 

             (40 to 55oC)

 

 

Incubate

 

             (40 to 55oC, 8 to 48 hours)  Enzymes

 

 

Repasteurise

 

               (72oC 25-35 minutes)

 

 

EMC Paste

 

                Spray dry or use direct