Food colors, development

Animals that do not readily accept pelleted feeds may be enticed to do so if the feed carries an odor that induces ingestion. Color development is an important consideration in aquarium species and some animals produced for human food. External coloration is desired in aquarium species. Pink flesh in cultured salmon is desired by much of the consuming pubHc. Coloration, whether external or of the flesh, can be achieved by incorporating ingredients that contain pigments or by adding extracts or synthetic compounds. One class of additives that imparts color is the carotenoids. 

A good compilation of the functions of fats in various food products is available (26). Some functions are quite subtle, eg, fats lend sheen, color, color development, and crystallinity. One of the principal roles is that of texture modification which includes viscosity, tenderness (shortening), control of ice crystals, elasticity, and flakiness, as in puff pastry. Fats also contribute to moisture retention, flavor in cultured dairy products, and heat transfer in deep fried foods. For the new technology of microwave cooking, fats assist in the distribution of the heating patterns of microwave cooking. 

Because of the multiple conjugated olefinic stmcture in the molecule, pure crystalline carotenoids are very sensitive to light and air and must be stored in sealed containers under vacuum or inert gas to prevent degradation. Thus, commercial utilization as food colorings was initially limited however, stable forms were developed and marketed as emulsions, oil solutions and suspensions, and spray-dried forms. 

W. C. Bainbridge, Ind. Eng Chem. 18, 1329—1331 (1926). Development of the food color industry in the United States. Interesting historically. 

S. H. Hochheiser, Synthetic Foods Colors in the United States A. History Under Regulation, University Microfilms International, 83-04269, Ann Arbor, Mich., 1986. An excellent history of the development of legislation to control colorants used in foods, dmgs, and cosmetics. 

J. Walford, ed.. Developments in Food Colours, Vols. 1 and 2. Elsevier AppHed Science, London, 1980 and 1984. Includes chapters on synthetic and natral food colors used in the United States, and on the influence of color on the perception and choice of food. 

The use of natural dyes as food colorants evolved over a period spanning thousands of years. During that period, by trial and error, some dyes were found to be safe while others were not. By comparison, the development of synthetic dyes as food colorants has taken place over a comparatively short time. During that period, some synthetic dyes considered safe by existing health standards were used as food colors. Later, with iacreased knowledge, these were found to create health problems and were removed from the marketplace. The manufacture of synthetic dyes for use on foods creates more of a health and environmental problem than natural dyes, but offers greater variety and stabiUty of color (see Dyes, environmental chemistry). 

Photoelectric-Colorimetric Method. Although the recording spectrophotometer is, for food work at least, a research tool, another instrument, the Hunter multipurpose reflectometer (4), is available and may prove to be applicable to industrial quality control. (The newer Hunter color and color difference meter which eliminates considerable calculation will probably be even more directly applicable. Another make of reflection meter has recently been made available commercially that uses filters similar to those developed by Hunter and can be used to obtain a similar type of data.) This instrument is not a spectrophotometer, for it does not primarily measure the variation of any property of samples with respect to wave length, but certain colorimetric indexes are calculated from separate readings with amber, blue, and green filters, designated A, B, and G, respectively. The most useful indexes in food color work obtainable with this type of instrument have been G, which gives a... 

Although chlorophyll and chlorophyllin colorants seem to be easily obtained, in practice their production as natural food colorants is rather difficult. The sensitivity of chlorophylls to certain enzymes, heat, and low pH, and their low tinctorial strength greatly limit their manufacture and application as food additives, principally when the pigments are isolated from the protective environment of the chloroplasts. The well-known instability of chlorophylls prompted extensive research for developing... 

Vareltzis, K., Buck, E.M., and Labbe, R.G., Effectiveness of a betalains/potassium sorbate system versus sodium nitrite for color development and control of total aerobes, Clostridium perfringens and Clostridium sporogenes in chicken frankfurters, J. Food Protect., 47, 532, 1984. 

Color plays a special role in the foods we eat. For example, when confronted with a food of an unattractive color, the consumer assumes the food is of poor quality or is spoiled. Similarly, a product with an atypical color, e.g., a green cheese or a blue drink, in most cases would be rejected by the consumer. Typically, one associates certain colors with certain food items such as cherry with red, lemon with yellow, and orange with carrot. Therefore, color can serve as a primary identification of food and also as a protective measure to prevent the consumption of spoiled food. Food colors create physiological and psychological expectations and attitudes that are developed by experience, tradition, education, and environment we inevitably eat with our eyes. ... 

Kirschbanm, 1. et al.. Development and evaluation of an HPLC-DAD method for determination of synthetic food colorants, Chromatogr. Suppl., 57, 115, 2003. 

In recent decades, the synthetic colorant market has dechned, to the benefit of the natural-oriented market and consumers. Excluding FD C Red 40 and Red 28, the synthetic colorants are now as well accepted as they were. In addition to the decreasing enthusiasm for chemicals in food, the high costs of toxicological studies also inhibit the development and approval of new synthetic colorants. The existing technologies used for the extraction, concentration, and purification of natural plant pigments to be used as food colorants still produce lower yields and the final products are still expensive. 

Parker, L.E., Regulatory approaches to food coloration, in Developments in Food Colors 2, Applied Science Publishers, London, 1984. 

Solutions obtained for the analysis of other food ingredients had the greatest color development, i.e., false gossypol values, at pH 5 to 6. False gossypol reactions could not be eliminated by altering the pH of the reacting solutions in the AOCS (19) procedure. It is essential to be able to accurately determine the amount of an... 

BPA can occur due to an incomplete polymerization, followed by migration into the food or environment [200], Furthermore, BPA monomer is used as color developer in thermal paper and is consequently also present in recycled paper and paperboard which can be used as food packaging material [201]. Human exposure to BPA is believed to occur mainly through contaminated food, although recently dermal exposure and absorption have gained attention [202-204]. 

Pedreschi, F., Leon, J., Mery, D., Moyano, R, Pedreschi, R., Kaack, K., Granby, K. (2007). Color development and acrylamide content of pre-dried potato chips. J. Food Eng., 79, 786-793. 

Kanner, J., and Juven, B. J. (1980). S-NitrosiKysteine as an antioxidant, color-developing, and anticlostridial agent in comminuted turkey meat. J. Food Sci. 45, 1105-1108 and 1112. 

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