American Oil Chemists Society, method

American Oil Chemists Society, method to determine gossypol contents of food products, 68-71... 

There are advantages and drawbacks for each of the aforementioned reagents. No single method can fulfill the methylation requirement for all kinds of samples. The BF3 method (see Basic Protocol 1), since its introduction by Metcalfe et al. (1961, 1966), has been widely used and is adopted as the official method for both the American Oil Chemists Society (methods Ce 2-66 and Ce lb-89 AOCS, 1989) and AOAC International (969.33 Firestone, 1995). The advantage of the BF3 method is that... 

Consistency of fats is commonly determined with the cone penetrometer, as specified in the Official and Tentative Methods of the American Oil Chemists Society (Method Cc 16-60). Other methods that have frequently been employed involve extrusion they include the extrusion attachment to the shear press (Vasic and deMan 1967), an extrusion rheometer used with the Instron universal testing machine (Scherr and Witt-nauer 1967), and the FIRA-NIRD extruder (Prentice 1954). 

Determination of four tocopherols and four tocotrienols in vegetable oils and fats by the official American Oil Chemists Society method is based on separation by normal-phase HPLC and fluorescence detection (AOCS, 1990). Oil samples are dissolved in hexane, whereas margarines and other fats containing vitamer esters need a cold saponification step to liberate the vitamers. The American Association of Cereal Chemists has a method to analyze vitamin E in various foods. This method (AACC, 1997) is applicable to a vitamin E range of 1 x 10" - 100%, and it includes hot saponification and separation by reversed-phase HPLC. Results are calculated as a-tocopherol acetate. The Royal Society of Chemistry has approved a method to analyze vitamin E in animal feedstuffs by normal-phase HPLC after the vitamers have been liberated by hot saponification (Analytical Methods Committee, 1990). 

Kyriakidis, N.B. and Katsiloulis, T. (2000) Calculation of iodine value from measurements of fatty acid methyl esters of some oils comparison with the relevant American Oil Chemists Society method. 

Examination of Water, Sewage and Industrial Wastes (American Public Health Association, New York, 1955) Standard Methods for the Examination of Dairy Products (American Public Health Association) Official Methods of Analysis (International Society of Leather Trades Chemists) which is in English and French Methods of Analysis of Fats and Feeds (American Oil Chemists Society), Methods of Analysis of Malt Beverages (American Society of Brewing Chemists). The British Standards Yearbook and its sectional lists contain much information of interest to analysts, as do the various national codexes, pharmacopeias and formularies. 

The methods of analysis of the American Oil Chemists Society (AOCS) are the principal procedures followed in the United States and Canada and are official in commercial transactions. When the material is for human consumption or dmg use, it must meet the specifications of the USP (12). Commercial distilled grades of glycerol do not requite purification before analysis by the usual methods. The deterrnination of glycerol content by the periodate method (13), which replaced the acetin and dichromate methods previously used, is more accurate and more specific as well as simpler and more rapid. 

Official and Tentative Methods, 3rd ed., American Oil Chemists Society, Chicago, lU., 1978, Ea6-51. 

The standard methods (26) of analysis for commercial lecithin, as embodied in the Official and Tentative Methods of the American Oil Chemists Society (AOCS), generally are used in the technical evaluation of lecithin (27). Eor example, the AOCS Ja 4-46 method determines the acetone-insoluble matter under the conditions of the test, free from sand, meal, and other petroleum ether-insoluble material. The phosphoHpids are included in the acetone-insoluble fraction. The substances insoluble in hexane are determined by method AOCS Ja 3-87. 

To analy2e fatty amines, both wet and instmmental methods of analysis are used. Wet methods routinely used are total amine value (ASTM Method D2073) combining weight or neutralization equivalent primary, secondary, and tertiary amine content (ASTM Method D2083) moisture, Kad-Fischer (ASTM Method D2072) and iodine value, measure of unsaturation (ASTM Method D2075). These provide important information on physical and chemical characteristics of the amine products used in various appHcation areas (8,76,81). In addition to the ASTM methods available, the American Oil Chemists Society has developed methods of analysis for fatty amines (82). 

D. Firestone, ed. Official Methods and Recommended Practices of theMmerican Oil Chemists Society, 3rd ed,Th.e American Oil Chemists Society, Champaign, lU., 1988. 

There are no universally accepted wet analytical methods for the characteri2ation of quaternary ammonium compounds. The American Oil Chemists Society (AOCS) has estabhshed, however, a number of appHcable tests (180). These include sampling, color, moisture, amine value, ash, iodine value, average molecular weight, pH, and flash point. 

There are a variety of analytical methods commonly used for the characterization of neat soap and bar soaps. Many of these methods have been pubUshed as official methods by the American Oil Chemists Society (29). Additionally, many analysts choose United States Pharmacopoeia (USP), British Pharmacopoeia (BP), or Pood Chemical Codex (FCC) methods. These methods tend to be colorimetric, potentiometric, or titrametric procedures. However, a variety of instmmental techniques are also frequendy utilized, eg, gas chromatography, high performance Hquid chromatography, nuclear magnetic resonance spectroscopy, infrared spectroscopy, and mass spectrometry. 

The American Society for Testing and Materials (ASTM) and the American Oil Chemists Society (AOCS) provide standard methods for determining properties that are important in characterization of dimer acids. Characterization of dimer acids for acid and saponification values, unsaponiftables, and specific gravity are done by AOCS standard methods ... 

Anonymous. "Official and Tentative Methods of the American Oil Chemists Society American Oil Chemists Society Champaign, Illinois, 1973. 

Standard analytical procedures were used to evaluate the composition of ingredients. Of the proximate analyses, nitrogen, lipids, and crude fiber were measured by American Oil Chemists Society (AOCS) methods (12) and moisture and ash by Association of Official Analytical Chemists (AOAC) methods (13). Amino acid analyses were performed by gas-liquid chromatography (14) except for tryptophan, which was analyzed colormetrically Tl5). In addition to these assays, certain tests of ingredient safety or spoilage were also performed, which space does not permit to be reported in this paper, to assure that ingredients met accepted standards for food safety (16). 

American Oil Chemists Society (AOCS), "Official and Tentative Methods (with updating through 1982)," 1982, 3rd ed. 

Miller HE. A simplified method for the evaluation of antioxidants, Journal Of The /American Oil Chemists Society. 1971 48(2) 91. 

Chu, B.S., Ichikawa, S., Kanafusa, S., Nakajima, M. (2007). Preparation of protein-stabilized p-carotene nanodispersions by emulsification-evaporation method. Journal of the American Oil Chemists Society, 84, 1053-1062. 

Several methods have been introduced which express the degree of oxidation deterioration in terms of hydroperoxides per unit weight of fat. The modified Stamm method (Hamm et at 1965), the most sensitive of the peroxide determinations, is based on the reaction of oxidized fat and 1,5-diphenyl-carbohydrazide to yield a red color. The Lea method (American Oil Chemists Society 1971) depends on the liberation of iodine from potassium iodide, wherein the amount of iodine liberated by the hydroperoxides is used as the measure of the extent of oxidative deterioration. The colorimetric ferric thiocyanate procedure adapted to dairy products by Loftus Hills and Thiel (1946), with modifications by various workers (Pont 1955 Stine et at 1954), involves conversion of the ferrous ion to the ferric state in the presence of ammonium thiocyanate, presumably by the hydroperoxides present, to yield the red pigment ferric thiocyanate. Newstead and Headifen (1981), who reexamined this method, recommend that the extraction of the fat from whole milk powder be carried out in complete darkness to avoid elevated peroxide values. Hamm and Hammond (1967) have shown that the results of these three methods can be interrelated by the use of the proper correction factors. However, those methods based on the direct or indirect determination of hydroperoxides which do not consider previous dismutations of these primary reaction products are not necessarily indicative of the extent of the reaction, nor do they correlate well with the degree of off-flavors in the product (Kliman et at. 1962). 

Many standardized functional property tests have been published. Standardized methods are available from many organizations, including the American Association of Cereal Chemists, American Oil Chemists Society, and International Dairy Federation. Generally, these methods have been tested in collaborative studies by several laboratories and found to be repeatable. Therefore the use of standardized methods may facilitate comparison of results between laboratories. Even though a method has been standardized, there is no guarantee that the test results will relate to protein functionality in a particular product or product application. Another problem is that most of the standardized tests are empirical. If any step in the procedure is changed or equipment is substituted, comparisons between laboratories may not be possible. 

American Oil Chemists Society. 1993a. AOCS Official Method Ca5a-40. Free Fatty Acid. Champaign, 111. 

Mossoba, M.M., Kramer, J.K.G., Delmonte. P. Yurawecz, M.P., and Rader, J.I. 2003. Official Methods for the Determination of Trans Fat. American Oil Chemists Society Press, Champaign, 111. 

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