Chemistry of Curing Reaction


Muscle pigments

  • There are a number of muscle pigments in meat including myoglobin, haemoglobin, the cytochromes, catalases, the flavins and other coloured substances.
  • Quantitatively the first two listed myoglobin and haemoglobin are abundant.
  • The lesser pigments also play role in colour development and stabilization.
  • Myoglobin and haemoglobin are complex proteins and undergo similar reaction in meat.
  • However, their roles in living tissues are quite different.
  • Haemolglobin is the red pigment found in blood and acts as the carrier for oxygen to the tissues.
  • Myoglobin is the predominant pigment in muscle and serves as the storage mechanism for oxygen at the

The Chemistry of curing reaction

  • Colour develops as a result of interaction of nitrite with the muscle pigments.
  • The nitrate and nitrite reactions in meat curing are as shown below
  • Nitrate reducing organisms

Curing reaction

Chemical changes of myoglobin that may occur during the curing reaction are as follows

Chemical changes of myoglobin

  • The ultimate pigment desired in most heat processed cured meats is the conversion of muscle pigment myoglobin into nitrosyl haemochrome (pink).

Undesirable Changes

  • Under some conditions the nitrosyl haemochrome pigment in meat may be oxidized to green, yellow or colourless porphyrin substances.
  • Such undesirable changes of the cured meat pigment may result from bacterial action or from chemical oxidation by peroxides, hypochlorites or other agents.
  • Light catalyzes these oxidative changes, as demonstrated by the tendency of cured meat surfaces to fade rapidly under strong light.

Curing Temperature

  • The curing room temperature is maintained at 3˚C in most curing commercial operations.
  • Bacon factories maintain their pickling cellars between 3.3 and 5.6°C, for at this temperature the growth of microorganisms is very slow, especially in the presence of salt.
Last modified: Tuesday, 10 April 2012, 7:29 AM