Methods of Analysis Approved by the Codex Alimentarius Commission. II. Determination of the Loss on Drying of Lactose: Collaborative Study1

1978 ◽  
Vol 61 (3) ◽  
pp. 558-560
Author(s):  
Charles T Bourland ◽  
Robert W Weik ◽  
Randall L Anderson ◽  
William Horwitz
Keyword(s):  
Collaborative Study ◽  
Codex Alimentarius ◽  
Forced Draft Oven ◽  
Codex Alimentarius Commission ◽  
Convection Oven ◽  
Methods Of Analysis ◽  
Significant Difference ◽  
Forced Draft ◽  
Better Than

Abstract A collaborative study was performed on the method recommended by the Codex Alimentarius Commission for determining loss on drying of lactose at 120°C for 16 hr. Eight samples of lactose were analyzed by 9 laboratories. Although there was no significant difference between the means of the values obtained with the convection and forced draft ovens, the precision attained by the 3 laboratories using a forced draft oven was considerably better than that attained by the laboratories using a convection oven. There is evidence that the directions for preparing samples of coarse crystals and lumpy products are inadequate

Convection Oven Determination of Loss of Mass on Drying of Quick Frozen French Fried Potatoes: Collaborative Study

1984 ◽  
Vol 67 (3) ◽  
pp. 635-636 ◽  
Author(s):  
David O Biltcliffe ◽  
Hillary J Judd ◽  
Roger Wood ◽  
◽  
A C Bushnell ◽  
...  
Keyword(s):  
Collaborative Study ◽  
Frozen Foods ◽  
Codex Alimentarius Commission ◽  
Convection Oven ◽  
Economic Commission ◽  
Two Samples ◽  
Repeatability And Reproducibility ◽  
Loss Of Mass ◽  
Fried Potatoes

Abstract A collaborative study was carried out on one of the methods submitted to the Joint Economic Commission for Europe (ECE)/Codex Alimentarius Commission Group of Experts on the Standardization of Quick Frozen Foods for the determination of moisture in quick frozen french (fried potatoes. The method was based on the determination of loss of mass of the sample on drying in a convection oven 16 h at 103±2°C. Two samples of uncooked quick frozen french fried potatoes and 2 samples of oven quick frozen french fried potatoes were analyzed by 14 and 13 laboratories, respectively. The method is simple and was found to be analytically satisfactory with repeatability and reproducibility values of 0.21 and 2.00 g/100 g french fried potatoes, and 0.29 and 3.00 g/100 g oven french fried potatoes, respectively. The method was adopted by the Group of Experts in preference to other proposed procedures for this determination. The method has been adopted official first action by AOAC.

Determination of Oven Moisture in Tobacco

1966 ◽  
Vol 49 (3) ◽  
pp. 525-528
Author(s):  
C E Bortner ◽  
C L Ogg
Keyword(s):  
Moisture Content ◽  
Organic Material ◽  
Oven Method ◽  
Forced Draft Oven ◽  
Oven Drying ◽  
Convection Oven ◽  
Volatile Organic ◽  
Forced Draft

Abstract A comparison of mechanical convection and gravity convection oven-drying of tobacco was made on 12 tobacco samples, six with high and six with low moisture content. Data show that better interlaboratory precision was obtained by drying in a mechanical convection oven. The term “apparent moisture” is vised becavise oven drying also causes loss of volatile organic material. The magnitude of this loss is shown to be from 0.25 to 1.5%, depending on the type and treatment of the tobacco. The forced draft oven method is recommended for adoption as official, first action.

Pyrolysis-Gas Chromatographic Techniques for the Analysis of Automobile Finishes: Collaborative Study

1976 ◽  
Vol 59 (1) ◽  
pp. 35-41 ◽  
Author(s):  
William D Stewart
Keyword(s):  
Mass Spectrometry ◽  
Infrared Spectroscopy ◽  
Collaborative Study ◽  
Pyrolysis Gas ◽  
Analytical Technique ◽  
Organic Vehicle ◽  
Unknown Sample ◽  
Chromatographic Techniques ◽  
Methods Of Analysis

Abstract Samples of 7 automobile topcoats currently used by the major American automobile manufacturers were analyzed by various pyrolysis-gas chromatographic techniques. The samples were similar shades of white paint with small differences in the organic vehicle composition. The study involved analysis of the 7 samples and identification of an unknown sample chosen from the 7. A ninth chip was also included for determination of the reproducibility of the analytical technique. The samples were analyzed by other methods of analysis, including diamond cell infrared spectroscopy and mass spectrometry. Sample sizes from 4 to 200 μg were needed for the various methods of analysis and, in all cases, the unknown sample was correctly identified.

Gas Chromatographic-Thermal Energy Analysis Method for Determination of Volatile N-Nitrosamines in Baby Bottle Rubber Nipples: Collaborative Study

1987 ◽  
Vol 70 (1) ◽  
pp. 64-68 ◽  
Author(s):  
J Ian Gray ◽  
Michael A Stachiw
Keyword(s):  
Thermal Energy ◽  
Energy Analysis ◽  
Collaborative Study ◽  
Internal Standard ◽  
Analytical Techniques ◽  
The United States ◽  
Baby Bottle ◽  
Relative Standard ◽  
Better Than

Abstract A collaborative study was conducted on the U.S. Food and Drug Administration (FDA) dichloromethane extraction method for determining volatile N-nitrosamines in baby bottle rubber nipples. Following dichloromethane extraction, A'-nitrosamines were determined by gas chromatography-thermal energy analysis. Six pairs of blind duplicate rubber nipple samples representing 6 lots were analyzed by 11 collaborating laboratories. All samples were portions taken from equilibrated composites of cut-up rubber nipples obtained from manufacturers in the United States. Recoveries of the internal standard (N-nitrosodipropylamine) at approximately 20 ppb ranged from 10 to 120%. Reproducibility relative standard deviations (RSDJ were between 35 and 45% for N-nitrosamine levels from 10 to 20 ppb. However, when data from laboratories with recoveries less than 75% were excluded (this is now specified in the method), RSD„ values were between 11 and 32% for N-nitrosamine levels from 6 to 26 ppb. Values were consistent with or better than those reported for other analytical techniques designed to quantitate trace contaminants at the low ppb level, e.g., afiatoxin in foods. The method has been adopted official first action for the quantitation of volatile N-nitrosamines in baby bottle rubber nipples.

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.

Gas Chromatographic Determination of Metribuzin in Formulations: Collaborative Study

1984 ◽  
Vol 67 (4) ◽  
pp. 840-843
Author(s):  
William R Betker ◽  
◽  
D Anderson ◽  
J M Bajovich ◽  
O O Bennett ◽  
...  
Keyword(s):  
Methylene Chloride ◽  
Collaborative Study ◽  
Internal Standard ◽  
Chromatographic Determination ◽  
Peak Height ◽  
Gas Chromatograph ◽  
Significant Difference ◽  
Butyl Phthalate ◽  
Gas Chromatographic Method

Abstract A collaborative study was conducted on a gas chromatographic method for determining metribuzin. Two 75% dry flow able and two 42% liquid flowable formulations were analyzed by 18 laboratories. Formulations were extracted by shaking or ultrasonic mixing for 1-5 min with methylene chloride which contained di-n-butyl phthalate as an internal standard. The extracts were injected into a gas chromatograph equipped with an OV-225 column. Peak area ratios and peak height ratios showed no significant difference. The reproducibility coefficient of variation was 0.75% for the 75% formulation and 1.41% for the 42% formulation. This GC method has been adopted official first action.

Methods of Analysis for Toxic Elements in Foods. Part IV. General Method of Ashing for the Determination of Toxic Elements

1993 ◽  
Vol 76 (2) ◽  
pp. 257-262 ◽  
Author(s):  
Igor M Skurikhin
Keyword(s):  
Toxic Elements ◽  
Codex Alimentarius ◽  
Methods Of Analysis ◽  
Dry Ashing ◽  
General Method

Abstract As a result of the request of the Codex Alimentarius Committee on Methods of Analysis and Sampling, a general method for ashing of foods for the determination of toxic elements was assembled. This method consolidates the results of more than a decade of interlaboratory work of numerous USSR food laboratories and specifies the details of wet and dry ashing procedures.

A COLLABORATIVE STUDY OF METHODS FOR THE DETERMINATION OF POTASSIUM, CALCIUM AND MAGNESIUM IN PLANT MATERIALS

1960 ◽  
Vol 40 (4) ◽  
pp. 589-595 ◽  
Author(s):  
G. M. Ward ◽  
H. B. Heeney
Keyword(s):  
Plant Tissue ◽  
Collaborative Study ◽  
Plant Materials ◽  
Reliable Determination ◽  
Flame Photometer ◽  
Methods Of Analysis ◽  
Calcium And Magnesium

Thirteen Canadian laboratories collaborated in a 2-year study of methods of analysis of plant tissue. The investigation has shown that the flame photometric procedure for potassium and a modification of the chelatometric method using EDTA for calcium and magnesium give the most consistent and reproducible results. Further research is necessary before the flame photometer can be used for the reliable determination of calcium and magnesium.

Collaborative Study of Accuracy and Precision of Rapid Determination of Fat in Meat and Meat Products by Foss-Let Method

1977 ◽  
Vol 60 (4) ◽  
pp. 853-858 ◽  
Author(s):  
Julio D Pettinati ◽  
Clifton E Swift
Keyword(s):  
Food Industry ◽  
Rapid Determination ◽  
Collaborative Study ◽  
Meat Products ◽  
T Test ◽  
Laboratory Sample ◽  
Accuracy And Precision ◽  
Aoac Method ◽  
Better Than

Abstract Collaborators in 12 meat and food industry laboratories performed 4 fat determinations each on 7 samples of meat and meat products by the rapid (7–10 min) Foss-Let method and compared the results with those obtained by AOAC method 24.005(a) or 24.005(b). From the overall mean of results on all samples, determinations by the Foss-Let method averaged 0.11% fat higher than by the AOAC method. This difference was not significant by the t-test (P = 0.05), which indicated agreement between the compared methods in determining fat content. Precision of the Foss-Let method was equivalent to and generally slightly better than that of the AOAC method. Standard deviations with the Foss-Let method were 0.2 % fat for between-duplicates and for within-laboratory repeatability; 0.4% fat for between-laboratories, including variation due to laboratory-sample interaction; and 0.5% fat for reproducibility between analysts in different laboratories. The Foss-Let method has been adopted as official first action.

Gas Chromatographic Determination of Metolachlor in Pesticide Formulations: Collaborative Study

1985 ◽  
Vol 68 (3) ◽  
pp. 570-572
Author(s):  
Thomas G Gale ◽  
Arthur H Hofberg
Keyword(s):  
Active Ingredient ◽  
Collaborative Study ◽  
Internal Standard ◽  
Chromatographic Determination ◽  
Matched Pair ◽  
Emulsifiable Concentrate ◽  
Flame Ionization ◽  
Pesticide Formulations ◽  
Better Than

Abstract A gas chromatographic (GC) procedure for the determination of metolachlor in emulsifiable concentrate formulations containing about 76% active ingredient was collaboratively studied using the matched pair scheme. Metolachlor was extracted from the formulation with acetone containing dipentyl phthalate as the internal standard, chromatographed on OV-101, and detected by flame ionization. Determinations on the 4 samples by 21 government, university, and industrial collaborators using peak area measurements showed within-laboratory repeatability of better than 0.5%. Reproducibility was better than 1% for the formulation. The method has been adopted official first action.

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