Meats, color changes cured

An unintentional gas-induced color change to meat occurs when it is exposed to sufficiently high levels of nitrogen dioxide (NOj) such as during incomplete combustion of gases in gas ovens. The surface of the meat becomes pink, much like the characteristic pink of cured meat, due to the formation of nitrosylhemochrome (Cornforth et al., 1998). 

Color changes in cured meats are induced by curing and/or drying and during storage (Sebranek, 1988). Depending on the process of preservation, a meat mixture may be subject to temperatures between ambient and... 

Sebranek (1988) has reviewed the effects of heat on denaturation of the proteins. Dehydration by heat denatures the muscle proteins, particularly the sarcoplasmic proteins. This induces a rather dramatic change in meat color. The heme pigments, which provide most of the color of fresh meat, serve as a general indication of doneness or temperature history. In the case of cured products, heme pigments react to form nitric oxide hemochro-mogen, which contributes the characteristic pink cured meat color (Pearson and Tauber, 1984). 

Hall, G. O. 1950. Curing of meat to avoid undesirable color change. U. S. patent 2,513,094. 

A color change to brown is observed when non-cured meat is heated. A Fe + complex is present which has its fifth and sixth coordination sites occupied by histidine residues of denatured meat proteins. 

In carcass decontamination dilute solutions of organic acids (1-3%) normally do not have any effect on the sensory properties of meat. However, it is known that lactic and acetic acid can produce unfavorable sensory changes if applied directly to meat cuts, which may be irreversible. Salts of organic acids are approved for use as food ingredients such as emulsifiers, color and flavor enhancers, and humectants. They are also used to enhance the quality of cooked or cured meat products and to control the pH (Smulders and Greer, 1998). Sodium lactate is approved for use as (1) a flavor enhancer, (2) humectant, and (3) pH control agent (Lemay et al., 2002). 

In addition to the curing salts and related processes mentioned above, additives collectively known as adjuncts are used in many cured meat products. These include ascorbates, phosphates, glucono-D-lactone, and sugars. Adjuncts are used primarily to obtain or maintain desirable changes, the ascorbates in connection with color and the others in connection with pH, texture, and in some cases flavor. Adjuncts may also affect safety. The concentration of each curing agent depends on the nature of the food products and on the technology used in individual countries [81]. 

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