Gas Chromatographic-Chemiluminescence Method for Determination of Volatile NNitrosamines in Minced Fish-Meat and Surimi-Meat Frankfurters: Collaborative Study

1990 ◽  
Vol 73 (6) ◽  
pp. 947-952
Author(s):  
John W Pensabene ◽  
Walter Fiddler ◽  
John G Phillips
Keyword(s):  
Extraction Method ◽  
Solid Phase ◽  
Collaborative Study ◽  
Energy Analyzer ◽  
Chemiluminescence Method ◽  
Fish Meat ◽  
Relative Standard ◽  
Minced Fish ◽  
Standard Deviations

Abstract A collaborative study was carried out on a solid-phase extraction method for separating volatile N-nltrosamlnes, particularly N-nltrosodlmethylamlne (NDMA), from combination minced fish or surlml-meat frankfurters with detection by gas chromatography-chemllumlnescence (thermal energy analyzer). The results from the 10 collaborators were evaluated using the most recent AOAC guidelines for determining outliers and for the analysis of variance. For NDMA, repeatability standard deviations, sr, ranged from 0.56 to 2.25; repeatability relative standard deviations, RSDr, ranged from 8.9 to 11.5%. Reproducibility standard deviations, sR, for NDMA ranged from 1.40 to 6.49, and reproducibility relative standard deviations, RSDR, ranged from 24.2 to 28.9%. Our data compared favorably to the reproducibility (RSDR) curve of Horwltz. The method has been adopted official first action by AOAC.

scholarly journals Determination of Ochratoxin A in Wine and Beer by Immunoaffinity Column Cleanup and Liquid Chromatographic Analysis with Fluorometric Detection: Collaborative Study

2001 ◽  
Vol 84 (6) ◽  
pp. 1818-1827 ◽  
Author(s):  
Angelo Visconti ◽  
Michelangelo Pascale ◽  
Gianluca Centonze ◽  
E Anklam ◽  
A M Betbeder ◽  
...  
Keyword(s):  
Ochratoxin A ◽  
Red Wine ◽  
Collaborative Study ◽  
White Wine ◽  
Fluorometric Detection ◽  
Immunoaffinity Column ◽  
Relative Standard ◽  
Standard Deviations ◽  
Liquid Chromatographic

Abstract The accuracy, repeatability, and reproducibility characteristics of a liquid chromatographic method for the determination of ochratoxin A (OTA) in white wine, red wine, and beer were established in a collaborative study involving 18 laboratories in 10 countries. Blind duplicates of blank, spiked, and naturally contaminated materials at levels ranging from ≤0.01 to 3.00 ng/mL were analyzed. Wine and beer samples were diluted with a solution containing polyethylene glycol and sodium hydrogen carbonate, and the diluted samples were filtered and cleaned up on an immunoaffinity column. OTA was eluted with methanol and quantified by reversed-phase liquid chromatography with fluorometric detection. Average recoveries from white wine, red wine, and beer ranged from 88.2 to 105.4% (at spiking levels ranging from 0.1 to 2.0 ng/mL), from 84.3 to 93.1% (at spiking levels ranging from 0.2 to 3.0 ng/mL), and from 87.0 to 95.0% (at spiking levels ranging from 0.2 to 1.5 ng/mL), respectively. Relative standard deviations for within-laboratory repeatability (RSDr) ranged from 6.6 to 10.8% for white wine, from 6.5 to 10.8% for red wine, and from 4.7 to 16.5% for beer. Relative standard deviations for between-laboratories reproducibility (RSDR) ranged from 13.1 to 15.9% for white wine, from 11.9 to 13.6% for red wine, and from 15.2 to 26.1% for beer. HORRAT values were ≤0.4 for the 3 matrixes.

Sulfuric Acid/Hydrogen Peroxide Digestion and Colorimetric Determination of Phosphorus in Meat and Meat Products: Collaborative Study

1991 ◽  
Vol 74 (1) ◽  
pp. 22-26 ◽  
Author(s):  
David K Christians ◽  
Thomas G Aspelund ◽  
Scott V Brayton ◽  
Larry L Roberts
Keyword(s):  
Hydrogen Peroxide ◽  
Sulfuric Acid ◽  
Collaborative Study ◽  
Meat Products ◽  
Colorimetric Determination ◽  
Pork Sausage ◽  
Relative Standard ◽  
Significant Difference ◽  
Standard Deviations

Abstract Seven laboratories participated In a collaborative study of a method for determination of phosphorus in meat and meat products. Samples are digested In sulfuric acid and hydrogen peroxide; digestion Is complete In approximately 10 mln. Phosphorus Is determined by colorimetric analysis of a dilute aliquot of the sample digest. The collaborators analyzed 3 sets of blind duplicate samples from each of 6 classes of meat (U.S. Department of Agriculture classifications): smoked ham, water-added ham, canned ham, pork sausage, cooked sausage, and hamburger. The calibration curve was linear over the range of standard solutions prepared (phosphorus levels from 0.05 to 1.00%); levels in the collaborative study samples ranged from 0.10 to 0.30%. Standard deviations for repeatability (sr) and reproducibility (sR) ranged from 0.004 to 0.012 and 0.007 to 0.014, respectively. Corresponding relative standard deviations (RSDr and RSDR, respectively) ranged from 1.70 to 7.28% and 3.50 to 9.87%. Six laboratories analyzed samples by both the proposed method and AOAC method 24.016 (14th Ed.). One laboratory reported results by the proposed method only. Statistical evaluations Indicated no significant difference between the 2 methods. The method has been adopted official first action by AOAC.

Generic Combustion Method for Determination of Crude Protein in Feeds: Collaborative Study

1989 ◽  
Vol 72 (5) ◽  
pp. 770-774 ◽  
Author(s):  
Rose A Sweeney
Keyword(s):  
Crude Protein ◽  
Collaborative Study ◽  
Combustion Method ◽  
Performance Requirements ◽  
General Terms ◽  
Relative Standard ◽  
Kjeldahl Method ◽  
Standard Deviations ◽  
And Performance

Abstract Nine laboratories participated in a collaborative study on determination of crude protein in animal feeds to compare a generically described combustion method with the AOAC mercury catalyst Kjeldahl method (7.015). The combustion method was written in general terms of method principle, apparatus specifications, and performance requirements. The sample set comprised closely matched pairs of feed ingredients and mixed products ranging from 10 to 90% protein. Ten pairs ground to 0.5 mm were the focus of the study; 4 pairs were ground to 1.0 mm for comparison. Nicotinic acid and lysine monohydrochloride were included as standards. Collaborators were instructed to report their results for performance checks using materials supplied. Only one laboratory failed to meet the proposed limits. Seven laboratories used the LECO Model FP-228 analyzer and 2 used the LECO CHN 600 analyzer. For the 0.5 mm pairs, repeatability standard deviations (sr) ranged from 0.09 to 0.58 for the Kjeldahl method and from 0.14 to 0.33 for the combustion method, with a pooled sr value of 0.28 and relative standard deviation (RSDr) of 0.59%. Reproducibility standard deviations (SR) ranged from 0.23 to 0.86 (Kjeldahl) and from 0.30 to 0.61 (combustion), with a pooled sR value of 0.52 and RSDR of 1.10%. Grand means for the samples ground to 0.5 mm were 47.65% protein by the combustion method and 47.41% protein by the Kjeldahl method. For samples ground to 1.0 mm, corresponding values were 31.82 and 31.50% protein. The generic combustion method has been approved interim official first action.

Liquid Chromatographic Method for Determination of Iodine in Milk: Collaborative Study

1993 ◽  
Vol 76 (4) ◽  
pp. 711-719 ◽  
Author(s):  
David Sertl ◽  
William Malone ◽  
◽  
P Beljaars ◽  
C Blake ◽  
...  
Keyword(s):  
Membrane Filter ◽  
Collaborative Study ◽  
Reversed Phase ◽  
Powdered Milk ◽  
Insoluble Material ◽  
Relative Standard ◽  
Repeatability And Reproducibility ◽  
Standard Deviations ◽  
Liquid Chromatographic

Abstract Nine laboratories participated in an AOAC International/ International Dairy Federation collaborative study on a liquid chromatographic (LC) method for determination of iodine in milk. Liquid milk is passed through a 25 000 MW membrane filter to remove protein and insoluble material. Iodine (in the form of iodide) in the clear filtrate is separated by reversed-phase ion-pair LC and is detected electrochemically. Participants analyzed 2 commercial pasteurized whole milks and 5 nonfat dry milk powders in blind duplicate. Each sample was tested in duplicate on 2 days. Repeatability and reproducibility standard deviations (sr and SR, respectively) and repeatability and reproducibility relative standard deviations (RSDr and RSDR, respectively) for determinations of iodine in whole milk (mean recovery, 86.7%) were as follows: sr, 22 μg/L; SR, 22 μg/L; RSDr, 8.2%; and RSDR, 8.3%. For powdered milk (mean recovery, 91 %), the values were as follows: sr, 0.14 μg/g; SR, 0.22 μg/g; RSDr, 9.0%; and RSDR, 12.7%. The method was adopted first action by AOAC International.

Determination of Total Taurine in Pet Foods by Liquid Chromatography of the Dansyl Derivative: Collaborative Study

2000 ◽  
Vol 83 (4) ◽  
pp. 784-788 ◽  
Author(s):  
Kieran McCarthy ◽  
Claudia Hischenhuber ◽  
Neil Joyce ◽  
G Cherix ◽  
C Hischenhuber ◽  
...  
Keyword(s):  
Liquid Chromatography ◽  
Fluorescence Detection ◽  
Collaborative Study ◽  
Gradient Elution ◽  
Taurine Concentration ◽  
Dansyl Derivative ◽  
Relative Standard ◽  
Standard Deviations ◽  
Liquid Chromatographic

Abstract A liquid chromatographic (LC) method for the determination of total taurine in pet foods was evaluated in a collaborative study. Ten laboratories assayed 6 blind duplicate pairs of wet and dry pet foods. The taurine in the 6 sample pairs ranged from low (170 mg/kg) to high (2250 mg/kg) concentrations as is. Collaborators also assayed a sample of known taurine concentration for familiarization purposes. Samples were hydrolyzed to release bound taurine, which was subsequently converted to the dansyl derivative and quantitated by gradient-elution LC with fluorescence detection. Repeatability relative standard deviations, RSDr, ranged from 3.2 to 10.0%; reproducibility relative standard deviations, RSDR, ranged from 6.1 to 16.1%. The method has been adopted Official First Action status by AOAC INTERNATIONAL.

scholarly journals Determination of Clopidol Residues in Chicken Tissues by Liquid Chromatography: Collaborative Study

2003 ◽  
Vol 86 (4) ◽  
pp. 685-693 ◽  
Author(s):  
Guo-Fang Pang ◽  
Yan-Zhong Cao ◽  
Chun-Lin Fan ◽  
Jin-Jie Zhang ◽  
Xue-Min Li ◽  
...  
Keyword(s):  
Liquid Chromatography ◽  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Solid Phase ◽  
Collaborative Study ◽  
Reversed Phase ◽  
Method Performance ◽  
Chicken Muscle ◽  
Relative Standard

Abstract Eighteen laboratories participated in a collaborative study on the determination of clopidol residues in chicken muscle tissues by liquid chromatography. Of these, results from 16 laboratories which rigorously followed the method were subjected to statistical analysis. The method performance was assessed by all participants using 14 samples of chicken muscle fortified at concentrations ranging from 0.1 to 5.0 mg/kg. In addition, 9 participants each reported results for 6 clopidol-incurred samples in chicken muscle. Test portions were extracted with acetonitrile, and the extracts were purified with alumina and anion exchange resin solid-phase extraction cartridges in sequence. Clopidol was separated by reversed-phase liquid chromatography and quantified at 270 nm. Average recoveries ranged from 81.8 to 85.4%, reproducibility relative standard deviation (RSDR) ranged from 11.9 to 22.6%, and repeatability relative standard deviation (RSDr) ranged from 9.9 to 15.1%. For clopidol-incurred samples at concentrations of 0.100–0.687 mg/kg, the mean determination value range was 0.099–0.659 mg/kg; RSDR was 12.6–19.8%, RSDr was 3.1–8.5%; and HORRAT values were 0.7–1.1. The accuracy and precision of the method are in conformity with the requirements specified by AOAC INTERNATIONAL. The method was adopted Official First Action in April 2003.

Atomic Absorption Spectrophotometric Method for Determination of Polydimethylsiloxane Residues in Pineapple Juice: Collaborative Study

1990 ◽  
Vol 73 (5) ◽  
pp. 721-723
Author(s):  
Robert D Parker
Keyword(s):  
Nitrous Oxide ◽  
Atomic Absorption ◽  
Spectrophotometric Method ◽  
Collaborative Study ◽  
Atomic Absorption Spectrophotometry ◽  
Pineapple Juice ◽  
Absorption Spectrophotometry ◽  
Relative Standard ◽  
Standard Deviations

Abstract An atomic absorption spectrophotometric method for determination of polydimethylsiloxane (PDMS) residues In pineapple juice was collaboratively studied by 9 laboratories. PDMS residues are extracted from pineapple Juice with 4- methyl-2-pentanone and the extracted silicone Is measured by atomic absorption spectrophotometry using a nitrous oxide/ acetylene flame. Collaborators analyzed 5 samples Including 1 blind duplicate. Reproducibility relative standard deviations (RSDR) were 13.1% at 31 ppm, 6.9% at 18 ppm, 14.8% at 7.9 ppm, and 16.1 % at 4.9 ppm PDMS. The method has been approved Interim official first action by AOAC.

Spectrophotometric Determination of Cyclamate in Soft Drinks and Desserts: Complementary Collaborative Study

1988 ◽  
Vol 71 (6) ◽  
pp. 1212-1214
Author(s):  
Anna-Maija K SJÖBERG
Keyword(s):  
Spectrophotometric Determination ◽  
Spectrophotometric Method ◽  
Soft Drink ◽  
Collaborative Study ◽  
Soft Drinks ◽  
Food Control ◽  
Average Recovery ◽  
Relative Standard ◽  
Standard Deviations

Abstract Fifteen official food control laboratories participated in a collaborative study of a spectrophotometric method to determine cyclamate in a soft drink and a dessert at concentrations of 90-311 mg/L and 202-526 mg/kg, respectively, with blind duplicates and a blank. Average recovery from the soft drink was 97.5%, and from the dessert, 98.6%. Reproducibility relative standard deviations were 4.7-6.5% and 6.9-8.5%, respectively. The outlier percentage was 5.5%. This study complements an earlier work by leading Nordic food laboratories and was designed according to the latest recommendations. The results of this study were compared with those of the earlier collaborative study and with general collaborative results obtained by AOAC.

Collaborative Study on Ashing: 1969

1970 ◽  
Vol 53 (5) ◽  
pp. 926-927
Author(s):  
Joseph Kowalczuk
Keyword(s):  
Atomic Absorption ◽  
Collaborative Study ◽  
Atomic Absorption Determination ◽  
Absorption Determination ◽  
Relative Standard ◽  
Dry Ashing ◽  
Standard Deviations ◽  
Calcium Iron

Abstract A collaborative study evaluated the effect of wet vs. dry ashing on the atomic absorption determination of calcium, iron, magnesium, manganese, and zinc in feeds. Ten laboratories analyzed 6 samples. The high relative standard deviations indicate that ashing methods should be further studied.

scholarly journals Determination of Arsenic in Seafood by Electrothermal Atomic Absorption Spectrometry after Microwave Digestion: NMKL Collaborative Study

2000 ◽  
Vol 83 (6) ◽  
pp. 1423-1428 ◽  
Author(s):  
Kaare Julshamn ◽  
Arngriimur Thorlacius ◽  
Per Lea ◽  
Kjetil Barland ◽  
Kari Eidem ◽  
...  
Keyword(s):  
Atomic Absorption Spectrometry ◽  
Atomic Absorption ◽  
Blue Mussel ◽  
Collaborative Study ◽  
Electrothermal Atomic Absorption Spectrometry ◽  
Absorption Spectrometry ◽  
Method Performance ◽  
Relative Standard ◽  
Standard Deviations

Abstract Eight laboratories participated in an interlaboratory method performance (collaborative) study of a method for the determination of arsenic in foodstuffs of marine origin by electrothermal atomic absorption spectrometry after wet digestion using a microwave oven technique. The study was preceded by a practice round of familiarization samples. The method was tested on 8 materials (cod roe, krill, blue mussel, saithe, scampi, cod fillet, shrimp, and cod extract) ranging in As content from 2 to 75 mg/kg. The materials were sent to participants in the study as blind duplicates, and the participants were asked to perform single determinations on each sample. Repeatability relative standard deviations (RSDr) for As ranged from 6.8 to 17.4%. Reproducibility relative standard deviations (RSDR) ranged from 7.6 to 24%. The highest RSDR value was found for the sample with the highest concentration of As.

Sign in / Sign up

Export Citation Format

Share Document