Determination of Fat,Moisture, and Protein in Meat and Meat Products by Using the FOSS FoodScan Near-Infrared Spectrophotometer with FOSS Artificial Neural Network Calibration Model and Associated Database: Collaborative Study

Abstract A collaborative study was conducted to evaluate the repeatability and reproducibility of the FOSS FoodScan near-infrared spectrophotometer with artificial neural network calibration model and database for the determination of fat, moisture, and protein in meat and meat products. Representative samples were homogenized by grinding according to AOAC Official Method 983.18. Approximately 180 g ground sample was placed in a 140 mm round sample dish, and the dish was placed in the FoodScan. The operator ID was entered, the meat product profile within the software was selected, and the scanning process was initiated by pressing the start button. Results were displayed for percent (g/100 g) fat, moisture, and protein. Ten blind duplicate samples were sent to 15 collaborators in the United States. The within-laboratory (repeatability) relative standard deviation (RSDr) ranged from 0.22 to 2.67% for fat, 0.23 to 0.92% for moisture, and 0.35 to 2.13% for protein. The between-laboratories (reproducibility) relative standard deviation (RSDR) ranged from 0.52 to 6.89% for fat, 0.39 to 1.55% for moisture, and 0.54 to 5.23% for protein. The method is recommended for Official First Action.

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Indirect and Direct Determination of the Casein Content of Milk by Kjeldahl Nitrogen Analysis: Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/81.4.763 ◽

1998 ◽

Vol 81 (4) ◽

pp. 763-774 ◽

Cited By ~ 58

Author(s):

Joanna M Lynch ◽

David M Barbano ◽

J Richard Fleming

Keyword(s):

Standard Deviation ◽

Nitrogen Content ◽

Relative Standard Deviation ◽

Collaborative Study ◽

Direct Determination ◽

Raw Milk ◽

Method Performance ◽

Relative Standard ◽

Milk Casein

Abstract The classic method for determination of milk casein is based on precipitation of casein at pH 4.6. Precipitated milk casein is removed by filtration and the nitrogen content of either the precipitate (direct casein method) or filtrate (noncasein nitrogen; NCN) is determined by Kjeldahl analysis. For the indirect casein method, milk total nitrogen (TN; Method 991.20) is also determined and casein is calculated as TN minus NCN. Ten laboratories tested 9 pairs of blind duplicate raw milk materials with a casein range of 2.42- 3.05℅ by both the direct and indirect casein methods. Statistical performance expressed in protein equivalents (nitrogen ⨯ 6.38) with invalid and outlier data removed was as follows: NCN method (wt%), mean = 0.762, sr = 0.010, SR = 0.016, repeatability relative standard deviation (RSDr) = 1.287℅, reproducibility relative standard deviation (RSDR) = 2.146%; indirect casein method (wt℅), mean = 2.585, repeatability = 0.015, reproducibility = 0.022, RSDr = 0.560℅, RSDR = 0.841; direct casein method (wt℅), mean = 2.575, sr = 0.015, sR = 0.025, RSDr = 0.597℅, RSDR = 0.988℅. Method performance was acceptable and comparable to similar Kjeldahl methods for determining nitrogen content of milk (Methods 991.20, 991.21,991.22, 991.23). The direct casein, indirect casein, and noncasein nitrogen methods have been adopted by AOAC INTERNATIONAL.

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Determination of Maleic Hydrazide Residues in Tobacco and Vegetables

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/56.5.1164 ◽

1973 ◽

Vol 56 (5) ◽

pp. 1164-1172

Author(s):

Milan Ihnat ◽

Robert J Westerby ◽

Israel Hoffman

Keyword(s):

Standard Deviation ◽

Present Method ◽

Maleic Hydrazide ◽

Collaborative Study ◽

Official Method ◽

Sample Weight ◽

Relative Standard ◽

The Mean ◽

Pipe Tobacco

Abstract The distillation-spectrophotometric method of Hoffman for determining maleic hydrazide has been modified to include a double distillation and was applied to the determination of 1–30 ppm maleic hydrazide residues in tobacco and vegetables. Recoveries of 1–23 μg added maleic hydrazide were independent of weight of maleic hydrazide, but did depend on sample and sample weight. The following recoveries were obtained from 0.5 g sample: pipe tobacco, 84%; commercially dehydrated potato, 83%; cigar tobacco, 81%; dried potato, 76%; fluecured tobacco, 73%; dried carrot, 71%. In the absence of sample, the recovery was 82%. When appropriate standard curves were used, maleic hydrazide levels determined in tobacco samples were essentially independent of sample weight in the range 0.1–3 g. The mean relative standard deviation for a variety of field-treated and fortified tobacco samples containing 1–28 ppm maleic hydrazide was 3%. The precision and sensitivity of this procedure seem to be substantial improvements over official method 29.111–29.117. It is recommended that the present method be subjected to a collaborative study.

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Liquid Chromatographic Determination of Ampicillin Residues in Porcine Muscle Tissue by a Multipenicillin Analytical Method: European Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/85.4.889 ◽

2002 ◽

Vol 85 (4) ◽

pp. 889-900 ◽

Cited By ~ 1

Author(s):

Eric Verdon ◽

Pierric Couëdor ◽

Pierre Maris ◽

Michel Laurentie ◽

P Batjoens ◽

...

Keyword(s):

Mass Spectrometry ◽

Standard Deviation ◽

Relative Standard Deviation ◽

Muscle Tissue ◽

Phosphate Buffer ◽

Collaborative Study ◽

Porcine Muscle ◽

Relative Standard ◽

Liquid Chromatographic

Abstract A collaborative study involving 14 laboratories was conducted to determine residues of ampicillin in porcine muscle tissue by using a liquid chromatographic method developed for multipenicillin analysis that can quantitate 8 penicillin compounds (benzylpenicillin, phenoxymethylpenicillin, ampicillin, amoxicillin, nafcillin, oxacillin, cloxacillin, and dicloxacillin) at trace levels in muscle tissue. This method involves extraction of the penicillins with phosphate buffer, pH 9, followed cleanup and concentration on a C18 solid-phase extraction column and reaction with benzoic anhydride at 50°C and with 1,2,4-triazole and mercury(II) chloride solution, pH 9.0, at 65°C. The derivatized compounds are eluted isocratically on a C8 column with a mobile phase of acetonitrile and phosphate buffer (pH 6; 0.1M) containing sodium thiosulfate and the ion-pair reagent tetrabutylammonium hydrogen sulfate. The penicillins are detected by UV absorption at 325 nm. The limit of detection and the limit of determination (quantitation) of the method were calculated to be approximately 3–5 and 25 μg/kg, respectively, in accordance with the criteria of European Union (EU) Decision No. 93/256/EEC. In this first interlaboratory study, collaborators were instructed to monitor 4 different penicillin compounds (benzylpenicillin, phenoxymethylpenicillin, ampicillin, and amoxicillin) by analyzing 8 blind samples of muscle tissue in triplicate. These samples were prepared from 2 materials containing different concentrations of incurred ampicillin (63.5 μg/kg for material No. 1 and 358.1 μg/kg for material No. 2) and 1 blank material. The repeatability relative standard deviation and the reproducibility relative standard deviation were 10.2 and 17.4%, respectively, for material No. 1 and 7.0 and 16.0%, respectively, for material No. 2. These results demonstrate that the method is suitable for the determination of ampicillin residues in muscle tissue at the EU maximum residue limit (50 μg/kg) and above. However, the identification of positives by this procedure may need additional confirmation by techniques with greater specificity, such as liquid chromatography combined with mass spectrometry, or tandem mass spectrometry. Investigations regarding the basis of interlaboratory testing studies will further demonstrate the suitability of multiresidue methodology for detecting and quantitating other compounds in the family of penicillin antibiotics.

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Crude Fat, Hexanes Extraction, in Feed, Cereal Grain, and Forage (Randall/Soxtec/Submersion Method): Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/86.5.899 ◽

2003 ◽

Vol 86 (5) ◽

pp. 899-908 ◽

Cited By ~ 34

Author(s):

Nancy J Thiex ◽

Shirley Anderson ◽

Bryan Gildemeister ◽

W Adcock ◽

J Boedigheimer ◽

...

Keyword(s):

Standard Deviation ◽

Relative Standard Deviation ◽

Animal Feed ◽

Collaborative Study ◽

Meat Products ◽

The United States ◽

Official Method ◽

Cereal Grain ◽

Relative Standard ◽

Time Required

Abstract A method for determining crude fat in animal feed, cereal grain, and forage (plant tissue) was collaboratively studied. Crude fat was extracted from the animal feed, cereal grain, or forage material with hexanes by the Randall method, also called the Soxtec method or the submersion method. The use of hexanes provides for an alternative to diethyl ether for fat extractions. The proposed submersion method considerably decreases the extraction time required to complete a batch of samples compared to Soxhlet. The increase in throughput is very desirable in the quest for faster turnaround times and the greater efficiency in the use of labor. In addition, this method provides for reclamation of the solvent as a step of the method. The submersion method for fat extraction was previously studied for meat and meat products and was accepted as AOAC Official Method 991.36. Fourteen blind samples were sent to 14 collaborators in the United States, Sweden, Canada, and Germany. The within-laboratory relative standard deviation (repeatability) ranged from 1.23 to 5.80% for crude fat. Among-laboratory (including within) relative standard deviation (reproducibility) ranged from 1.88 to 14.1%. The method is recommended for Official First Action.

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

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/74.1.22 ◽

1991 ◽

Vol 74 (1) ◽

pp. 22-26 ◽

Cited By ~ 1

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.

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Determination of Cholecalciferol (Vitamin D3) in Selected Foods by Liquid Chromatography: NMKL Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/86.2.400 ◽

2003 ◽

Vol 86 (2) ◽

pp. 400-406 ◽

Cited By ~ 20

Author(s):

Anders Staffas ◽

Arne Nyman ◽

K Ask ◽

E Hermansson ◽

J S Jacobsen ◽

...

Keyword(s):

Liquid Chromatography ◽

Standard Deviation ◽

Fish Oil ◽

Vitamin D3 ◽

Collaborative Study ◽

The Other ◽

Vitamin D2 ◽

Cooking Oil ◽

Relative Standard

Abstract Results are presented from an NMKL (Nordic Committee on Food Analysis) collaborative study of a method for the determination of cholecalciferol (vitamin D3) in foods. The method is based on the addition of an internal standard (vitamin D2), followed by saponification and extraction with n-heptane. The fraction that contains vitamin D2/D3 is separated by preparative normal-phase liquid chromatography (LC), and the analytes are determined by reversed-phase LC with UV detection at 265 nm. The method was tested by 8 participating laboratories. In this study 6 different matrixes were analyzed for cholecalciferol content: milk, liquid infant formula (gruel), cooking oil, margarine, infant formula, and fish oil. The contents varied from 0.4 to 12 μg/100 g. Three matrixes (milk, gruel, and margarine) were fortified with vitamin D3. In the other matrixes, vitamin D3 was added at 3 different levels at the Swedish National Food Administration. The milk was analyzed as a blind duplicate, whereas the other matrixes were analyzed as split-level pairs. The recoveries from the samples with vitamin D3 added varied from 93 to 102%. The repeatability relative standard deviation (RSDr) values for accepted results varied between 2.2% (fish oil) and 7.4% (cooking oil), whereas the reproducibility relative standard deviation (RSDR) values varied between 6.8% (margarine) and 24% (cooking oil).

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Crude Fat, Diethyl Ether Extraction, in Feed, Cereal Grain, and Forage (Randall/Soxtec/Submersion Method): Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/86.5.888 ◽

2003 ◽

Vol 86 (5) ◽

pp. 888-898 ◽

Cited By ~ 81

Author(s):

Nancy J Thiex ◽

Shirley Anderson ◽

Bryan Gildemeister ◽

W Adcock ◽

J Boedigheimer ◽

...

Keyword(s):

Standard Deviation ◽

Relative Standard Deviation ◽

Diethyl Ether ◽

Animal Feed ◽

Collaborative Study ◽

Meat Products ◽

The United States ◽

Official Method ◽

Cereal Grain ◽

Relative Standard

Abstract A method for determining crude fat in animal feed, cereal grain, and forage (plant tissue) was collaboratively studied. Crude fat was extracted from the animal feed, cereal grain, or forage material with diethyl ether by the Randall method, also called the Soxtec method or the submersion method. The proposed submersion method considerably decreases the extraction time required to complete a batch of samples. The increase in throughput is very desirable in the quest for faster turnaround times and the greater efficiency in the use of labor. In addition, this method provides for reclamation of the solvent as a step of the method. The submersion method for fat extraction was previously studied for meat and meat products and was accepted as AOAC Official Method 991.36. Fourteen blind samples were sent to 12 collaborators in the United States, Sweden, Canada, and Germany. The within-laboratory relative standard deviation (repeatability) ranged from 1.09 to 9.26% for crude fat. Among-laboratory (including within) relative standard deviation (reproducibility) ranged from 1.0 to 21.0%. The method is recommended for Official First Action.

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Determination of p-Toluenesulfonamide in Ice Cream by Combination of Continuous Flow and Liquid Chromatography: Summary of Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/77.3.672 ◽

1994 ◽

Vol 77 (3) ◽

pp. 672-674 ◽

Cited By ~ 3

Author(s):

Paul R Beuaars ◽

Remmelt Van Dijk ◽

Arie Brands

Keyword(s):

Liquid Chromatography ◽

Standard Deviation ◽

Relative Standard Deviation ◽

Continuous Flow ◽

Collaborative Study ◽

Ice Cream ◽

Relative Standard ◽

On Line ◽

Positive Results

Abstract A collaborative study of the determination of p-tolu-enesulfonamide (p-TSA) in ice cream by a combination of continuous flow and on-line liquid chromatography was conducted. Seven ice cream samples containing 0-6.35 mg p-TSA/kg at 4 levels (1 blank and 3 pairs of split level samples) were analyzed by 11 laboratories. For all samples analyzed, the repeatability relative standard deviation varied from 2.08 to 3.67%, whereas the reproducibility relative standard deviation ranged from 7.79 to 11.68%. The average p-TSA values for the split levels 1,2, and 3 were 0.55,1.02, and 4.44 mg p-TSA/kg, respectively, with mean recoveries ranging from 76 to 79% (overall recovery range for all levels, 63-101 %). No false positive results were reported for the blank sample, and no interference was encountered by the presence of vanillin in samples. The method has been adopted first action by AOAC INTERNATIONAL.

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Method for the Rapid Determination of Protein in Meats Using the CEM Sprint™ Protein Analyzer: Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/94.5.1555 ◽

2011 ◽

Vol 94 (5) ◽

pp. 1555-1561

Author(s):

Cindy Moser ◽

Kathy Herman ◽

K Barnhardt ◽

M Ceizyk ◽

T Chriscoe ◽

...

Keyword(s):

Standard Deviation ◽

Relative Standard Deviation ◽

Rapid Determination ◽

Collaborative Study ◽

Meat Products ◽

The United States ◽

Processed Meat ◽

Binding Agent ◽

Relative Standard ◽

Dye Binding

Abstract A collaborative study was conducted to determine the protein content of raw and processed meat products by a protein-tagging and colorimetric technique. Meat products were prepared following AOAC Official MethodSM 983.18 and analyzed using CEM Corporation's Sprint Rapid Protein Analyzer. Sprint provides protein results by combining an accurately weighed test portion with a known amount of dye-binding agent. The dye-binding agent binds with the lysine, histidine, and arginine, as well as the n-terminus of the proteins commonly found in raw meat and processed meat products. Results are displayed and reported by the Sprint as a percentage (g/100 g) of protein. Ten blind duplicate study samples were sent to 10 collaborating laboratories in the United States. The within-laboratory (repeatability) relative standard deviation (RSDr) ranged from 0.91 to 3.04%, and between-laboratories (reproducibility) relative standard deviation (RSDR) ranged from 1.50 to 3.41% for protein. The method is recommended for Official First Action.

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

Journal of AOAC International ◽

10.1093/jaoac/86.4.685 ◽

2003 ◽

Vol 86 (4) ◽

pp. 685-693 ◽

Cited By ~ 3

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.

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