Foods 314 INDEX

Methods are described for determining the extent to which original natural color is preserved in processing and subsequent storage of foods. Color differences may be evaluated indirectly in terms of some physical characteristic of the sample or extracted fraction thereof that is largely responsible for the color characteristics. For evaluation more directly in terms of what the observer actually sees, color differences are measured by reflectance spectrophotometry and photoelectric colorimetry and expressed as differences in psychophysical indexes such as luminous reflectance and chromaticity. The reflectance spectro-photometric method provides time-constant records in research investigation on foods, while photoelectric colorimeters and reflectometers may prove useful in industrial color applications. Psychophysical notation may be converted by standard methods to the colorimetrically more descriptive terms of Munsell hue, value, and chroma. Here color charts are useful for a direct evaluation of results. 

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... 

Direct or indirect methods may be used to determine moisture in dehydrated foods. Indirect methods must be calibrated in terms of direct methods—the most common of which are the oven, distillation, and Fischer methods. Accuracy of the direct methods is difficult to evaluate except by comparison with a chosen reference method. Several reference methods are reviewed, but none can be given an unqualified recommendation as most practical and suitable for all foods. An indirect measure of moisture is the equilibrium vapor pressure of water, which can be measured easily and accurately. Arguments are presented to show that vapor pressure may be a better index of the stability of dehydrated foods than the moisture content, which has been frequently used for this purpose. 

AAoisture determination is probably one of the most important and most widely used analytical measurements in the processing and testing of food products. It is of economic importance both to the consumer and to the food technologist. To the technologist, the moisture content is frequently an index of stability and quality of food, while to the consumer, it may serve as a measure of quantity as well as a measure of quality. 

Pressure of Water Vapor as an Index of Moisture in Dehydrated Foods... 

The advantages of vapor pressure as an index of moisture have been discussed. At the present time very few vapor pressure data are available for foods. It would be of great interest to measure vapor pressure concurrently with the moisture content in order to determine the usefulness of the vapor pressure in studies on the stability of dehydrated foods. 

Because the quality and health aspects of foods cannot be measured by a single index, it necessarily follows that the subject of control methods in the canned food industry is very broad, and includes chemical, physical, organoleptic, and bacteriological tests, only the first of which is discussed here. The measurement of color, odor, optical clarity, texture, viscosity, and chemical composition has been used to evaluate canned foods, but in many cases the methods that are applicable to one product are either not applicable to another, or can be used only after considerable modification. 

In certain cases, such as the treatment of zoo animals or endangered species, it may be impossible to recover the cost of approval of a drug for that species. In such circumstances, the FDA can add the drug to an index oflegally marketed non-approved drugs. A drug can only be indexed for use in situations vhere there is no risk of it entering the human food chain. 

The applicability of the linear-mixing model is seen most prominently in the interpretation of the 5 C of bone apatite which has been shown to represent the total diet, rather than being derived from energy foods , as was previously proposed by some authors. Although 5 C,p should represent total diet, the isotopic fractionation between this component and total diet appears to be somewhat variable, suggesting that more definite knowledge about this fractionation is needed if we are to use 5 C,p as an index of total dietaiy 5 C values. 

On the GM debate and biosafety research, a review of results performed under the European Commission supervision ( EC-sponsored Research on Safety of Genetically Modified Organisms , edited by C. Kessler and I. Economidis) is available also online at the EU-website http //europa.eu.int/ comm/research/quality-of-life/gmo/. An update on current research in food safety, nutrition and food-related disease might be found in the websites of the World Health Organization, http //www.who.int/fsf/GMfood/index.htm, and of the UK Food Standards Agency, http //www.foodstandards.gov.uk/. 

SCF (2000). Opinion of the Scientific Committee on Food on the Tolerable Upper Intake Level of Beta Carotene. Scientific Committee on Food, http //europa.eu.int/comm/ food/fs/sc/scf/index en.html. 

Fuleki, T. and Francis, F.J., Quantitative methods for anthocyanins. 2. Determination of total anthocyanin and degradation index for cranberry juice, J. Food Set, 33, 78, 1968. 

European-Commission, Food additives and flavorings, retrieved Jannary 9, 2006, http //enropa.en.int/comin/food/fs/sfp/flav index en.html, 2006. 

Food legislation in the US was implemented in 1938 and since then has been improved dynamically. The Food, Drug and Cosmetic Act classified specific colorants to be used in food and non-food products (FD C colorants). Each colorant has a color index (Cl) number and Cl name. Colorants are also identified by their Chemical Abstract Service (CAS) registry code numbers. The two groups are Certifiable Colorants and Exempt Colorants. 

Food Colorant Color CAS Color Index EU Code EU Status FDA Code FDA Status JECFA Status... 

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