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.

Partially Hydrolyzed Gluten in Fermented Cereal-Based Products by R5 Competitive ELISA: Collaborative Study, First Action 2015.05

2015 ◽  
Vol 98 (5) ◽  
pp. 1346-1354 ◽  
Author(s):  
Markus Lacorn ◽  
Thomas Weiss
Keyword(s):  
Collaborative Study ◽  
Technical Committee ◽  
Competitive Elisa ◽  
New Method ◽  
Fermented Foods ◽  
Gluten Free ◽  
Free Products ◽  
Elisa System ◽  
Fermented Products

Abstract In 2008, the AACC International Protein Technical Committee (now Protein and Enzymes Technical Committee) initiated a collaborative study of a method for determining gluten in fermented products, using an R5 competitive ELISA system. The method has been approved as AACCI Approved Method AACCI 38-55.02. The new method has been validated for testing fermented foods and beverages to determine that they conform to the Codex threshold of 20 mg of gluten/kg in total for gluten-free products. It is recommended that the method be accepted by AOAC as Official First Action.

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.

Gluten in Rice Flour and Baked Rice Products by G12 Sandwich ELISA: First Action 2014.03

2015 ◽  
Vol 98 (1) ◽  
pp. 103-111 ◽  
Author(s):  
Elisabeth Halbmayr-Jech ◽  
Adrian Rogers ◽  
Clyde Don ◽  
Michael Prinster ◽  
G Augustin ◽  
...  
Keyword(s):  
Sandwich Elisa ◽  
Collaborative Study ◽  
Rice Flour ◽  
Elisa Test ◽  
Technical Committee ◽  
Free Products ◽  
Heat Treated ◽  
Test Kit ◽  
Low Levels ◽  
Ppm Level

Abstract The Protein and Enzymes Technical Committee of American Association of Cereal Chemists initiated a collaborative study to confirm whether the G12 antibody-based sandwich ELISA test kit is able to detect gluten in the lower mg/kg (ppm) level. Twenty laboratories investigated 24 heat-treated and non-heat-treated blind-coded samples with incurred gluten levels up to 100 mg/kg. The method has been validated for testing foods to conform to the defined Codex thresholds for gluten in gluten-free products at less than 20 mg gluten/kg. The collaborative study showed that low levels of gluten could be detected by G12 Sandwich ELISA with reproducibility RSDR of 32%and repeatability RSDr of 16%. Incurred samples showed a recovery between 62 and 135%. It is recommended that the method be accepted by AOAC as 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.

Liquid Chromatographic Determination of Vanillin and Related Flavor Compounds in Vanilla Extract: Cooperative Study

1985 ◽  
Vol 68 (6) ◽  
pp. 1198-1201 ◽  
Author(s):  
Philip A Guarino ◽  
Susan M Brown
Keyword(s):  
Collaborative Study ◽  
Chromatographic Determination ◽  
Technical Committee ◽  
Flavor Compounds ◽  
Official Method ◽  
Ethyl Vanillin ◽  
Liquid Chromatographic Determination ◽  
Phase Liquid ◽  
Liquid Chromatographic

Abstract Vanillin and related flavor compounds present in vanilla extract were determined by reverse phase liquid chromatography. Results compared favorably with the official AOAC spectrophotometric method. Compounds such as p-hydroxybenzaldehyde and ethyl vanillin known to interfere in the official method were resolved from vanillin. The method was evaluated by 6 industrial laboratories under the aegis of the Technical Committee of the Flavor and Extract Manufacturers Association. The method is suggested for AOAC collaborative study.

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.

Collaborative Study of a Potentiometric Method for the Determination of Fluoride in Vegetation

1975 ◽  
Vol 58 (6) ◽  
pp. 1129-1134 ◽  
Author(s):  
Jay S Jacobson ◽  
Laurence I Heller
Keyword(s):  
Reference Values ◽  
Collaborative Study ◽  
Fluoride Concentration ◽  
Practical Method ◽  
Potentiometric Method ◽  
Selective Electrode ◽  
Collaborative Test ◽  
Relative Standard ◽  
Vegetation Samples

Abstract A collaborative test was performed to evaluate a new potentiometric method for the analysis of fluoride in vegetation. The study was designed to provide estimates of accuracy and within- and between-laboratory precision of a method that employs extraction of fluoride, followed by analysis with an ion selective electrode. A group of laboratories experienced in fluoride analysis was provided with representative aliquots of specially prepared samples of vegetation and a detailed set of instructions. Reference values were established for the fluoride concentrations of vegetation samples prior to their distribution. Nine of the 23 laboratories participating in the study adhered strictly to instructions so the results from these 9 participants were used to evaluate the method. The coefficient of correlation between results from selected laboratories and reference values was 0.999. Deviations from reference values averaged 5.4% and relative standard deviations ranged from about 20% at 24 ppm to about 10% for concentrations >100 ppm fluoride. On the basis of these results, the new method has been adopted as official first action. The method is simpler and faster; it requires less equipment than the current official final action method (25.029–29.035) and can be used to estimate fluoride concentration in the foliage of plants exposed to fluorides in the atmosphere or in soils provided samples contain >10 ppm fluoride. Separate studies indicate, however, that certain samples of vegetation may be refractory to analysis by this potentiometric method. The final action method should be retained until a practical method is developed that is satisfactory for all types of vegetation.

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