Collaborative Study of a Method for the Determination of Commercial Sterility of Low-Acid Canned Foods

1972 ◽  
Vol 55 (3) ◽  
pp. 613-616
Author(s):  
C B Dexxy
Keyword(s):  
Collaborative Study ◽  
Hand Washing ◽  
Microbiological Method ◽  
Laboratory Worker ◽  
Collaborative Test ◽  
Canned Foods ◽  
The Individual ◽  
Head Cover ◽  
Laboratory Contamination

Abstract A microbiological method for examining canned foods for commercial sterility to minimize contamination by the individual laboratory worker has been developed. Previous comparative tests by 7 laboratories and an earlier collaborative test with 9 food laboratories had shown considerable laboratory contamination, but had provided useful information as to appropriate apparatus, reagents, and procedures. Simple baud washing with soap was compared with the following procedure: hand and face washing, followed by washing of hands and face with a detergent sanitizer solution, and the wearing of a disposable operating room cap. Persons with beards, mustaches, or sideburns below the ear lobe were not permitted to perform the test. Eight specially prepared commercial cans of salmon were examined by 12 collaborating laboratories; 4 were examined after the simple hand washing procedure and 4 by the double washing and head-cover technique. Results showed that 25% of the laboratories experienced laboratory contamination by using only simple hand washing as compared to 0% using the double washing and head-cover technique. The microbiological method, including the double washing and head-cover technique, has been adopted as official first action.

Automated Method for the Determination of Niacin and Niacinamide in Cereal Products: Collaborative Study

1975 ◽  
Vol 58 (4) ◽  
pp. 799-803
Author(s):  
Anthony F Gross
Keyword(s):  
Chemical Method ◽  
Collaborative Study ◽  
Pet Food ◽  
Microbiological Method ◽  
Chemical Methods ◽  
Cereal Products ◽  
Automated Method ◽  
Coefficients Of Variation ◽  
Baked Products

Abstract In a collaborative study, an automated method for the determination of niacin and niacinamide in cereal products was compared with the official final action microbiological (43.121–43.125) and chemical (43.044–43.046) methods. Ten samples of cereal products, including enriched flour, yeast-leavened baked products, fortified breakfast cereals, and baked pet food products, were submitted to 14 laboratories. Nine laboratories reported values by the automated method, 6 reported values by the microbiological method, and 7 reported values by the chemical method. The results from the microbiological method were not subjected to analysis of variance because of the unusually large between-laboratory variation. The between-laboratory coefficients of variation for the automated and chemical methods were 10.90 and 10.18%, on the basis of results from 7 and 4 laboratories, respectively. There was no significant (p>0.05) difference between methods when results from the 4 laboratories who used both methods were compared. The automated chemical method has been adopted as official first action.

Collaborative Study of a Semiautomated Method for the Analysis of Prednisolone and Prednisone Tablets

1977 ◽  
Vol 60 (1) ◽  
pp. 27-31
Author(s):  
James F Brower
Keyword(s):  
Collaborative Study ◽  
Colorimetric Method ◽  
Alcoholic Solution ◽  
Tetramethylammonium Hydroxide ◽  
Assay Method ◽  
Blue Tetrazolium ◽  
Coefficients Of Variation ◽  
The Individual ◽  
Semiautomated Method

Abstract A semiautomated colorimetric method for the determination of prednisolone and prednisone was collaboratively studied by 6 collaborators. In the method, an alcoholic solution of the drug is extracted with chloroform and the extract is reacted with tetramethylammonium hydroxide and blue tetrazolium; the absorbance of the resulting color is read at 525 nm. Collaborators were supplied with 4 composites of tablets of different dosage levels, 2 containing prednisolone and 2 containing prednisone. Results agreed with those obtained by the author using the CSP total steroid assay method. The coefficients of variation of the individual collaborator’s results for prednisolone and prednisone ranged from 0.54 to 2.38 and from 0.34 to 2.19%, respectively. This method has been adopted as official first action.

scholarly journals Liquid Chromatographic Determination of Fumonisins B1, B2, and B3 in Corn: AOAC–IUPAC Collaborative Study

1996 ◽  
Vol 79 (3) ◽  
pp. 688-696 ◽  
Author(s):  
Eric W Sydenham ◽  
Gordon S Shephard ◽  
Pieter G Thiel ◽  
Sonja Stockenström ◽  
Petra W Snijman ◽  
...  
Keyword(s):  
Simultaneous Determination ◽  
Collaborative Study ◽  
Chromatographic Determination ◽  
Relative Standard ◽  
Valid Data ◽  
Liquid Chromatographic Determination ◽  
Standard Deviations ◽  
The Individual ◽  
Liquid Chromatographic

Abstract A liquid chromatographic (LC) method for simultaneous determination of fumonisins B1 (FB1), B2 (FB2), and B3 (FB3) in corn was subjected to a collaborative study involving 12 participants from 10 countries, in which the accuracy and reproducibility characteristics of the method were established. Mean analyte recoveries from corn ranged from 81.1 to 84.2% for FB1 (at a spiking range of 500 to 8000 ng/g), from 75.9 to 81.9% for FB2 (at a spiking range of 200 to 3200 ng/g), and from 75.8 to 86.8% for FB3 (at a spiking range of 100 to 1600 ng/g). The valid data were statistically evaluated after exclusion of outliers. Relative standard deviations for within-laboratory repeatability ranged from 5.8 to 13.2% for FB1, from 7.2 to 17.5% for FB2, and from 8.0 to 17.2% for FB3. Relative standard deviations for between-laboratory reproducibility varied from 13.9 to 22.2% for FB1, from 15.8 to 26.7% for FB2, and from 19.5 to 24.9% for FB3. HORRAT ratios, calculated for the individual toxin analogues, ranged from 0.75 to 1.73. The LC method for determination of fumonisins B1, B2, and B3 in corn (at concentrations of 800–12800 ng total fumonisins/g) has been adopted by AOAC INTERNATIONAL.

Collaborative Study of Acid-Detergent Fiber and Lignin

1973 ◽  
Vol 56 (4) ◽  
pp. 781-784 ◽  
Author(s):  
Peter J Van Soest
Keyword(s):  
Wheat Straw ◽  
Soybean Meal ◽  
Standard Error ◽  
Coefficient Of Variation ◽  
Collaborative Study ◽  
Barley Straw ◽  
Acid Detergent Fiber ◽  
Collaborative Test ◽  
Definition Of

Abstract A second collaborative study on acid-detergent fiber and lignin has been completed involving 10 laboratories and 6 samples including timothy, alfalfa, soybean meal, barley straw, orchardgrass, and wheat straw. Results from 7 laboratories appeared normal according to the Youden collaborative test and yielded a mean duplicate error of 0.40±0.31, a standard error between laboratories of 0.40, and a coefficient of variation of 1.02%. The duplicate error for lignin was 0.23±0.31, the standard error between laboratories, 0.28, and the coefficient of variation, 4.26%. Results indicate problems with filtering, handling fritted glass crucibles in a uniform weighing procedure, and reliably preparing asbestos used in the preparation of lignin. Modifications of the previously published method include reduction of sample size to 1 g, elimination of the use of decalin, rigorous definition of filtration and weighing procedures, use of P2O5 or Mg(ClO4)2 as desiccant, and determination of a lignin blank. Problems in filtration can be overcome by not using more vacuum than is necessary, making all additions with vacuum off, and allowing 15–30 sec settling before applying suction. The modified acid-detergent fiber and lignin method has been adopted as official first action.

Atomic Absorption Spectrophotometric Determination of Tin in Canned Foods, Using Nitric Acid-Hydrochloric Acid Digestion and Nitrous Oxide-Acetylene Flame: Collaborative Study

1985 ◽  
Vol 68 (2) ◽  
pp. 209-213
Author(s):  
Robert W Dabeka ◽  
Arthur D Mckenzie ◽  
Richard H Albert
Keyword(s):  
Atomic Absorption ◽  
Coefficient Of Variation ◽  
Collaborative Study ◽  
Statistical Treatment ◽  
Green Beans ◽  
Pineapple Juice ◽  
Tomato Paste ◽  
Quantitation Limit ◽  
Canned Foods

Abstract Twenty-six collaborators participated in a study to evaluate an atomic absorption spectrophotometric (AAS) method for the determination of tin in canned foods. The 5 foods evaluated were meat, pineapple juice, tomato paste, evaporated milk, and green beans, each spiked at 2 levels. The concentration range of tin in the samples was 10-450 μg/ g, and each level was sent as a blind duplicate. Statistical treatment of results revealed no laboratory outliers and 6 individual or replicatetotal outliers, accounting for 3.3% of the data. Repeatability (withinlaboratory) coefficient of variation (CVo) ranged from 2.2 to 48%, depending on the tin level and food evaluated. For samples containing >80 μg/g of tin, repeatability CV averaged 5.6% including outliers and 3.7% after their rejection. Overall among-laboratories coefficient of variation (CVX) varied from 3.3 to 58%; at levels >80 μg/g, it averaged 7.3% with outliers and 5.3% after their rejection. Recovery of tin, based on spiking levels, ranged from 100.0 to 112.8% and averaged 105.4%. Detection limit range is 2-10 μg/g, and lower quantitation limit is 40 μg/g. This method has been adopted official first action.

Determination of Natamycin in Cheese and Cheese Rind: Interlaboratory Collaborative Study

1987 ◽  
Vol 70 (6) ◽  
pp. 949-954
Author(s):  
Willem G Deruig
Keyword(s):  
Coefficient Of Variation ◽  
Collaborative Study ◽  
Spectrometric Method ◽  
Ultraviolet Detection ◽  
Collaborative Test ◽  
Low Levels ◽  
Liquid Chromatographic

Abstract A collaborative test on the determination of natamycin in cheese and cheese rind was conducted. Participants were from 37 laboratories in 13 countries. Eight samples, consisting of 4 duplicates, were investigated by a spectrometric method and a liquid chromatographic (LC) method. The spectrometric method gave good results (coefficient of variation [CV] = 12%) and the LC method with ultraviolet detection gave reasonable results (CV = 25%) for levels down to 15 mg/ kg (0.9 mg/dm2). For very low levels, a preconcentration step is necessary, but even then quantitation is poor (CV = 35-37%) for both methods at 1.7 mg/kg, although the presence of natamycin can be detected qualitatively. For a level of 0.3 mg/kg, quantitation is poor (CV = 39%) for the LC method and impossible (CV = 60%) for the spectrometric method.

Determination of Gluten in Processed and Nonprocessed Corn Products by Qualitative R5 Immunochromatographic Dipstick: Collaborative Study, First Action 2015.16

2016 ◽  
Vol 99 (3) ◽  
pp. 730-737 ◽  
Author(s):  
Markus Lacorn ◽  
Katharina Scherf ◽  
Steffen Uhlig ◽  
Thomas Weiss ◽  
G Augustin ◽  
...  
Keyword(s):  
Qualitative Analysis ◽  
Collaborative Study ◽  
Technical Committee ◽  
Gluten Free ◽  
Free Products ◽  
Collaborative Test ◽  
Corn Products

Abstract In September 2013, the AACC International (AACI) Protein Technical Committee (now Protein and Enzymes Technical Committee) initiated a collaborative study of a method for the qualitative analysis of intact gluten in processed and nonprocessed corn products, using an R5 immunochromatographic dipstick system. It was validated to demonstrate that potential gluten-free products contain gluten lower than the Codex threshold of 20 mg/kg gluten. The results of the collaborative test with 18 participants confirmed that the method is suitable to detect gluten contaminations that are clearly lower than the threshold. It is recommended that the method be accepted by AOAC as Official First Action.

Liquid Chromatographic Determination of Levodopa and Levodopa-Carbidopa in Solid Dosage Forms: Collaborative Study

1987 ◽  
Vol 70 (6) ◽  
pp. 987-990 ◽  
Author(s):  
Susan Ting
Keyword(s):  
Coefficient Of Variation ◽  
Collaborative Study ◽  
Chromatographic Determination ◽  
Content Uniformity ◽  
Solid Dosage ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic Determination ◽  
The Individual ◽  
Liquid Chromatographic

Abstract A liquid chromatographic method for the determination of levodopa in tablets and capsules and levodopa-carbidopa in tablets was collaboratively studied by 6 laboratories. Collaborators were supplied with duplicate powdered composites of levodopa (1 synthetic formulation, 1 commercial tablet, and 1 commercial capsule) and levodopa- carbidopa (1 synthetic formulation and 2 commercial tablets), along with individual levodopa-carbidopa tablets for content uniformity determinations. The repeatability coefficient of variation (CV„) and reproducibility coefficient of variation (CV„) for levodopa single component were 0.48 and 0.87%; for levodopa in combination, 0.50 and 0.90%; and for carbidopa, 0.77 and 1.20%, respectively. Overall, the recovery values for levodopa and carbidopa from synthetic formulations simulating tablets were 100.4 and 99.5%, respectively .The pooled CVD„ and CVDX values for the individual tablet assays were 2.07 and 2.30% for levodopa, and 1.80 and 2.24% for carbidopa, respectively. The method has been adopted official first action for determination of the active ingredients in levodopa tablets and capsules and in levodopa-carbidopa tablets and for content uniformity testing in the combination dosage form.

Collaborative Study of a Colorimetric Determination of Nitroglycerin in Sublingual Tablets

1972 ◽  
Vol 55 (1) ◽  
pp. 187-189
Author(s):  
Yvonne H Pfabe
Keyword(s):  
Collaborative Study ◽  
Colorimetric Determination ◽  
Coefficients Of Variation ◽  
Ethylenediamine Dihydrochloride ◽  
The Individual ◽  
Low Dosage

Abstract The colorimetric determination of nitroglycerin in tablets (JAOAC 53, 579–581 (1970)) was collaboratively studied by 13 laboratories. The nitroglycerin is hydrolyzed to nitrite, which diazotizes p-chloroaniline; this diazotization product is coupled with N-(l-naphthyl)- ethylenediamine dihydrochloride and measured at 560 nm. Samples were analyzed at a composite level (1.2 mg) and at an individual tablet level (0.15–0.6 mg). Coefficients of variation ranged from 4 to 14%, with the highest variation in the individual assay of low dosage tablets. Samples analyzed by the Associate Referee 6 months after the first analysis showed lower assay results, indicating deterioration. It is recommended that this study be continued.

Liquid Chromatographic Determination of Sugars in Licorice Extracts: Collaborative Study

1984 ◽  
Vol 67 (4) ◽  
pp. 764-767
Author(s):  
Pramathesh S Vora ◽  
Raymond M Tuorto ◽  
◽  
F Atchley ◽  
W Conway ◽  
...  
Keyword(s):  
Liquid Chromatography ◽  
Collaborative Study ◽  
Chromatographic Determination ◽  
Sugar Concentration ◽  
Wide Range ◽  
Liquid Chromatographic Determination ◽  
The Individual ◽  
Liquid Chromatographic

Abstract A collaborative study to determine fructose, glucose, sucrose, and maltose in a variety of licorice extracts has been performed using liquid chromatography. Six collaborators participated in the study, and each collaborator was sent 5 samples which were analyzed in blind replicates. A practice sample was used with a specific range of 8-10% fructose, 10-12% glucose, and 5-7% sucrose. The individual sugar concentration of the 5 samples ranged from 2.0 to 10%. AH samples were quantitated by comparing results with a pure sugar standard containing fructose, glucose, sucrose, and maltose and analyzed under the same conditions. No significant problems were encountered running the practice or other samples despite the wide range of instruments and columns used. Results showed less deviation within laboratories compared with results obtained among laboratories. The method has been adopted official first action.

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