Pigments in meat

R. Sakata, Studies on physicochemical characteristics of red pigments in meat products. Animal Sci. J. 71 (2000) 1-16. 

Hydrogen peroxide can even catch microbial criminals, like those that produce the green iridescence sometimes seen on ham or other cold cuts. Bacteria, as do humans, produce peroxide, which attacks myoglobin, the reddish pigment in meat. 

Colorants and pigments, in meats Color density, see also Colorimetry Colorimetry, see also Color analysis amylose, 689-692... 

Krzywicki, K. 1982. The determination of haem pigments in meat. Meat Sci. 7 29-36. 

The reactions of the heme pigments in meat and meat products have been summarized in the scheme presented in Figure 6-13 (Fox 1966). Bilin-type structures are formed when the porphyrin ring system is broken. 

In addition to the independent oxidation of unsaturated fats and of the heme pigments in meat, there is also a reaction between the two which brings about their mutual oxidation, accelerating both rancidity and color loss. 

The loss of vitamin C may also occur during reactions of ascorbic acid with some of the reactive food components. In particular, reactions of ascorbic acid with quinones generated by enzymatic browning reactions, reactions with nitrites and haem pigments in meat and meat products are technologically significant. 

Both nicotinic acid and nicotinamide have been used in the enrichment of bread, flour, and other grain-derived products. Animal feed is routinely supplemented with nicotinic acid and nicotinamide. Nicotinamide is also used in multivitamin preparations. Nicotinic acid is rarely used in this appHcation. The amide and carboxyHc acid have been used as a hrightener in electroplating baths and as stabili2er for pigmentation in cured meats. 

Paprika contains capsombin and capsanthin (Fig. 8.3) which occur mainly as the lauric acid esters, and about 20 other carotenoid pigments. Paprika is produced in many countries which have developed their own specialties. Cayenne or cayenne pepper, produced from a different cultivar of C. annum, is usually more pungent. C. frutescens is the source of the very pungent Tabasco sauce. Paprika oleoresin is produced by solvent extraction of the ground powder. Obviously paprika supplies both flavor and color and its use is limited to those products compatible with the flavor. The recent rise in demand for tomato products in the form of pizza, salsa, etc., has increased the demand for paprika. Paprika is used in meat products, soups, sauces, salad dressings, processed cheese, snacks, confectionery and baked goods.1018... 

In meat curing, nitrite is traditionally used for developing the pink, heat-stable pigment. Its other important role is the inhibition of the outgrowth of Clostridium botulinum spores in pasteurized products and, in some countries, in several types of smoked fish. Nitrite also serves as an antioxidant and contributes positively to the development of the flavor of cured-meat. The undesirable side-effect, however, is the reaction of nitrite with amino groups of food constituents, leading to the formation of NNCs. 

Vitamin A (retinol) is the parent substance of the retinoids, which include retinal and retinoic acid. The retinoids also can be synthesized by cleavage from the provitamin (3-car-otene. Retinoids are found in meat-containing diets, whereas p-carotene occurs in fruits and vegetables (particularly carrots). Retinal is involved in visual processes as the pigment of... 

Color and color uniformity are important criteria for retail acceptance of both fresh and processed meats. This unit describes the methods for detection and quantitation of pigments in nitrite-cured or uncured cooked meats. Protocols for measurement of fresh meat pigments are presented in UN1TF3.3. 

The Hornsey (1956) procedure and its modifications have received widespread acceptance as relatively rapid measures of the adequacy of cure development in processed meats. The Hornsey procedure is also an accurate method for nutritional assessment of heme and heme iron content of meats (Carpenter and Clark, 1995), where ppm heme iron = ppm total heme/11.7. However, one caveat should be noted. The total heme pigment measurement is higher in cured meats than in similar uncured samples. Roasted turkey breast meat, for example, was reported by Ahn and Maurer (1989a) to have 23,26,34, and 34 ppm total pigment in samples formulated with 0, 1, 10, and 50 ppm nitrite, respectively. This effect should be considered to avoid overestimation of the heme iron content of cured meats. 

Some investigators have soaked cooked meat slices in freshly prepared 1% sodium dithionite solution to maintain the pigments in the reduced state. However, this is not truly representative of the fresh meat slice, since dithionite will also reduce the brown globin hemichromes, intensifying the pink color to a level greater than that actually observed after slicing. 

This paper is an adaptation of the Hornsey (1956) method for measurement of nitrosyl and total heme pigments in cured meats, using 2 g meat samples rather than 10 g samples. Thus, less reagent is needed and more samples may be analyzed at the same time. 

Franke, W.C. and Solberg, M. 1971. Quantitative determination of metmyoglobin and total pigment in an intact meat sample using reflectance spectrophotometry. J. Food Sci. 36 515-519. 

Mohler, K. 1974. Formation of curing pigments by chemical, biochemical or enzymatic reactions. In Proceedings of the International Symposium on Nitrite in Meat Products. Wageningen, The Netherlands Center for Agricultural Publishing and Documentation. 

Meat proteins include sarcoplasmic, myofibrillar, and connective tissue proteins. Among the sarcoplasmic proteins are heme pigments and enzymes, which influence the color, smell, and structure of meat. Myofibrillar proteins and collagen are able to retain and hold water in meat structure and to emulsify fat. Therefore they influence the rheological properties of meat products. 

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