Association of Official Agricultural Chemists

Method 13.86 as published in Official Methods of Analysis, 8th Ed., Association of Official Agricultural Chemists Washington, DC, 1955,... 

Official Methods ofMnalysis 8th ed., W. Horwitz, ed.. Association of Official Agricultural Chemists, Washiagton, D.C., 1955, p. 826. 

A successful program of quality control also involves maintenance of sanitary conditions and production of products free from adulteration, contamination, and filth. Methods given by the Association of Official Agricultural Chemists (1) should be applied to the finished product to ensure against seizure and prosecution by federal and state food and drug authorities. In many instances such methods of analysis are not adaptable to production-line control and less accurate but more rapid methods must be substituted. With such procedures, more severe tolerances must be used to provide a sufficient margin of safety. 

Association of Official Agricultural Chemists, "Official and Tentative Methods," 6th ed., 1945. 

Though the literature is replete with methods of measuring the moisture content, truly accurate as well as practical methods are virtually nonexistent in the food field. The situation is well illustrated in what is probably the best compendium on this subject, the Official and Tentative Methods of Analysis of the Association of Official Agricultural Chemists (2). It becomes apparent from an examination of this volume that the stress is laid not so much on accuracy as on reproducibility and practicability of a method. Though these last two factors are for the most part the only ones of importance in the control of processing procedures and in standardization of products of commerce, the factor of accuracy is, nevertheless, of extreme importance to the research worker who endeavors to establish broad quantitative generalizations for the conditions that govern the stability of foods. 

In one procedure that has been widely used, the sample, after suitable treatment, is refluxed with sodium and isopropyl alcohol, after which the solution is diluted with water and the inorganic chloride is determined by standard methods (13, 54) The method has been adopted by the Association of Official Agricultural Chemists 29, 30) as a tentative one for technical DDT and for dusts, oil solutions, and aqueous emulsions of DDT, for use in the absence of other chlorine-containing compounds. The National Association of Insecticide and Disinfectant Manufacturers has also accepted the total-chlorine method for the analysis of these preparations 28). Essentially the same procedures have been described by Donovan 22), of the Insecticide Division of the Production and Marketing Administration, for technical DDT and various commercial DDT products containing no other compounds interfering with the chlorine determination. 

A procedure that has been widely used for spray residues is the separation of the residue from the sample by extraction with an organic solvent, usually benzene. After most of the solvent has been removed, the residue is treated with sodium and isopropyl alcohol and the chloride ion is estimated by standard methods. Carter 10) has determined in this manner DDT residues on a number of crops, and he has recommended the adoption by the Association of Official Agricultural Chemists of the method as a tentative one for DDT 11). Koblitsky and Chisholm 42) have determined DDT in soil samples by the sodium-isopropyl alcohol procedure after removing the DDT by extraction with an azeotropic mixture of two volumes of benzene and one volume of isopropyl alcohol. 

LaClair (44) and Soloway et al. (SO) have modified the dehydrohalogenation reaction to permit the determination of p,p -DDT in dusts and oil solutions containing technical DDT. The reaction between the base and the halide is carried out at 20° to 30° C., as Cristol (16) has found that under proper conditions at this temperature the p,p -DDT reacts completely, whereas the o,p -DDT and most of the impurities react only slightly. The Association of Official Agricultural Chemists (3) tentative method for the determination of the purity of p,p -DDT, which employs the dehydrohalogenation procedure, has been modified by Fleck (30) so that the reaction is carried out at 25° C. instead of under reflux conditions. 

Selenium on and in the peel of apples was determined by the procedure of the Association of Official Agricultural Chemists (1). Samples of approximately 1 kg. of whole fruit were hand-peeled with a Devault peeler and the parings were digested as directed (1, 29.60). 

Resistant starch will serve as primary source of substrate for colonic microflora and may have important physiological benefits. On this basis resistant starch can be classified as a dietary fibre. The Association of Official Agricultural Chemists (AOAC) method of determining dietary fibre will measure some resistant starch as dietary fibre. 

Gehrke, C.W., Ussary, J.P. and Kramer, G.H. Jr (1 964) Automation of the AOAC flame photometric method for potassium in fertilizers. Journal of the Association of Official Agricultural Chemists 47, 459 69. 

By 1900 many analytical procedures were available. Dujardin-Salleron (France) not only codified these procedures but also produced the necessary equipment for them (I). Official methods of wine analysis were soon developed in France and many other countries, and our own Association of Official Agricultural Chemists began developing tentative and official methods of wine analysis as early as 1916 (2) these continue to the present (3). Official methods of analysis, both for reference and routine purposes, are given on the international field by the Office International de la Vigne et du Vin (4) and by Amerine and Ough (5). For current American practices see Refs. 3, 5, 6, 7, 8, 9, 10, 11, 12, 12a. For European procedures see Refs. 4, 9,13,14,15,16,17,18,19,20,21,22,23. 

ASSOCIATION OF OFFICIAL ANALYTICAL CHEMISTS (AOAC). Formerly called the Association of Official Agricultural Chemists. It was founded in 1884. There arc 3000 members. These scientists develop, tost and study methods for analyzing fertilize , foods, feeds, diugs, pesticides, cosmetics, and other products related to agricultural and public health. It is located at 1111 N. 19th St.. Ste. 210, Arlington. VA. 22209. http //w-ww.aoac org/... 

For these determinations and for the preliminary operations mentioned, the directions laid down by the International Association of Leather Trades Chemists are officially adopted in Europe. These specify also that the results should always represent the mean of two distinct and concordant analyses. The official methods used in America are those of the Association of Official Agricultural Chemists of the United States and of the American Leather Chemists Association and differ in some details from the European methods (see Allen s Commercial Organic Analysis, 1911, 4th edit., Vol. V, pp. 76 et seq.). 

Youden WJ (1962) The collaborative test, presented at the Referees Seventy-sixth Annual Meeting of the Association of Official Agricultural Chemists, Washington, D.C., 16.October... 

To this end, the committee members drew up a letter and questionnaire soliciting the help of all of the above cited agencies in addition to the National Research Council physicists and chemists, members of the American Drug Manufacturers Association, United States Pharmacopoeia, National Formulary, Bureau of Chemistry of the Association of Official Agricultural Chemists, teachers in the leading college of pharmacy, etc. In all, 700 questionnaires were sent out. Of these 700, only 52 answers were received while 13 stated they "...were not interested in the problem."... 

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