Official analysis methods

Olive oils must satisfy various instrumental analytical parameters and conform to legal limits, restrictions and precise panel test scores. 

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Note, moreover, that some member states have published official analysis methods that do not always correspond to the official EU methods. This is the case of France, which has published two methods for thioglycolic acid and its disulphide in depilatories and for Chloramine T in cosmetics, respectively. 

A sterilization process may thus be developed without a full microbiological background to the product, instead being based on the ability to deal with a worst case condition. This is indeed the situation for official sterilization methods which must be capable of general application, and modem pharmacopoeial recommendations are derived firm a careful analysis of experimental data on bacterial spore survival following treatments with heat, ionizing radiation or gas. 

The Pesticide Analytical Manual of the US Food and Drug Administration or the Official Methods of Analysis of AOAC International are method collections with international recognition. Both compilations are written in English, one prerequisite for its success. Method collections of EU Member States are most often available only in the national languages. Eor this reason, they are relatively unknown in other Member States. Fortunately, some good collections of official national methods are translated into the English language. The most important are... 

There are several publications detailing standard or officially recognized methods of fertilizer analysis. These include Official Methods of Analysis of AOAC International (Horwitz, 2000) Official and Standardised Methods of Analysis, published by the Royal Society of Chemistry (Watson, 1994) and Fertilisers - Methods of Analysis used in OEEC Countries (OEEC, 1952). There are also the EEC methods, which have been implemented in the UK by the Fertilisers (Sampling and Analysis) Regulations 1996 (Statutory Instrument (SI) 1996 No. 1342). The title page of the SI may be downloaded from the following website ... 

The colorimetric method based on the reagents of Folin and Denis or of Folin and Ciocalteu has been generally preferred over other methods to determine total phenols in complex natural materials such as wines and fruits (1, 2, 3, 4, 5). This method is relatively simple, convenient, reliable, generally applicable, and it is accepted as an official analysis in several countries for total phenols in wines and a number of other products. Although it is a preferred method, it can be even better than is commonly recognized. 

AOAC, 1999a. Official Methods of Analysis Method 988.05. Ch. 4, p. 13 AOAC International, Gaithersburg, Md. 

Table D1.5.1 Conventional Analysis Methods of a-Tocopherol and a-Tocopheryl Acetate in the AOAC International Official Methods of Analysis...

Accurate, precise, sensitive, and rapid analytical determinations are as essential in food science and technology as in chemistry, biochemistry, and other physical and biological sciences. In many cases, the same methodologies are used. How does one, especially a young scientist, select the best methods to use A review of original publications in a given field indicates that some methods are cited repeatedly by many noted researchers and analysts, but with some modifications adapting them to the specific material analyzed. Official analytical methods have been adopted by some professional societies, such as the Official Methods of Analysis (Association of Official Analytical Chemists), Official Methods and Recommendation Practices (American Oil Chemists Society), and Official Methods of Analysis (American Association of Cereal Chemists). 

Reliable analysis methods based on TLC, HPLC, GC, ELISA, and EIA are available for the determination of zearalenone, a-zearalenol, and /3-zearalenol. As far as the application of HPLC in the analysis of zearalenone is concerned, the Bennett et al. method (100) has also been adopted as an official method of analysis by the Association of Official Analytical Chemists International (17). The method involves extraction with chloroform and purification with liquid/liquid partition into 2% sodium hydroxide. After additional purification steps, determination is performed by C18 with a fluorescence detection (236 nm excitation, 418 nm emission). The method also allows for the determination of -zearalenone, and both analytes are determined in corn at levels... 

Proposals for new limits prepared by Commission Working Parties are submitted to the Standing Committee for Foodstuffs, which consists of representatives of the Member States, but is chaired by the Commission. Decisions on new limits are usually made by the Commission according to a Regulatory Committee procedure (Procedure Illb) - for details see section 13.3.4. The Commission publishes the limits as a Regulation in the Official Journal. Methods of sampling and analysis to check compliance with the maximum levels laid down are also published. 

Commission Decision 93/351/EEC of 19 May 1993 determining analysis methods, sampling plans and maximum limits for mercury in fishery products. Official Journal of the European Communities. No. L 144, pp. 23-24. 

Castro et al. [64] reported a comparison between derivative spectro-photometric and liquid chromatographic methods for the determination of omeprazole in aqueous solutions during stability studies. The first derivative procedure was based on the linear relationship between the omeprazole concentration and the first derivative amplitude at 313 nm. The first derivative spectra were developed between 200 and 400 nm (A/ = 8). This method was validated and compared with the official HPLC method of the USP. It showed good linearity in the range of concentration studied (10—30 /ig/ ml), precision (repeatability and interday reproducibility), recovery, and specificity in stability studies. It also seemed to be 2.59 times more sensitive than the HPLC method. These results allowed to consider this procedure as useful for rapid analysis of omeprazole in stability studies since there was no interference with its decomposition products. 

Bahbouh et al. used a conductimetric method for the analysis of dipyridamole [21], Ground tablets containing the drug were dissolved in 100 mL of 67% ethanol, and a portion was transferred to a titration cell equipped with a conductivity cell. The sample solution was diluted to 50 mL with water and titrated with 5 mM phosphotungstic acid. After each addition of titrant, conductivity measurements were recorded after a 2 min interval and plotted against the amount of titrant added. The end point was determined at the curve break. Results obtained by this method were in good agreement with those obtained by the official pharmacopoeial methods. 

Official analytical methods provide data and results that give soundproof of the authenticity and quality of an olive oil, or, alternatively, elements that permit the uncovering of altered and sophisticated over-classified oils. This section is not to be regarded as a comprehensive presentation of olive oil chemistry and analysis but is intended only to give the reader an overall perspective of the origin and fate, and the chemico-physical properties, of the classes of compounds constituting olive oil. 

The only oils in commerce that do have a legal definition backed by officially sanctioned methods of analysis are the various grades of olive oil. The second chapter discusses the production of these oils and its relationship to the various grades, and the officially sanctioned methods of analysis are described by an acknowledged expert in this field. 

Cold Test. The ability of an oil to withstand refrigerator storage is determined by the cold test analysis crystallization resistance is measured as the time in hours before the oil appears cloudy at 32°F or 0°C. Standardized AOCS Method Cc 11-53 requires that dry filtered oil be placed in a sealed 4-ounce bottle and submerged into an ice bath (103). A go/no-go examination after 5.5 hours for clarity is stipulated by the Official AOCS Method however, most laboratories practice the alternative procedure, which continues the clarity examinations until a cloud... 

Analytical measurements would be made using methods and equipment which had been tested to ensure they were fit for the purpose. These would be officially recognised methods or laboratory methods which were validated by analysis of certified samples or interlaboratory comparisons. 

Motohashi, N., Nagashima, H., Parkanyi, C., and Subrahmanyam, B., Official multiresidue methods of pesticide analysis in vegetables, fruits and soil, J. Chromatogr. A, 754, 333-346, 1996. 

The analysis of silicone products such as simethicone can be performed with good selectivity, using H NMR spectroscopy. The NMR-method was cross-validated [2] against the official IR-method [66]. 

Note When determining any nitrogen ingredients in fertilizer, known and blank standards should be used before the final official analysis is stated. Corrections should be made for the blank on all samples and the known standards should be within 0.1% N. If a known NIST (National Institute of Standards and Technology) standard reference material is available, it should be used to verify the method and to verify other internal check samples. 

Table 5 Official AOAC methods of analysis applicable to preservatives ...

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