Application of the AOAC Official Method of Analysis for determination of ochratoxin A in brown rice: Inter laboratory study

Abstract The AOAC official method, 24.029–24.035, for the determination of fluorine in foods was modified slightly to o btain quantitative recoveries of fluorine from samples of fish protein concentrate (FPC). The most important alterations include the use of steam distillation, the addition of finely ground silica sand in the distillation, a decrease in the distillation temperature, and the utilization of direct titration. Recoveries of fluoride added to FPC before ashing, using this modified method, averaged 96.0 ± 3.0%. Our results are in agreement with those of several other analysts who used a variety of methods.

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Allyl Isothiocyanate in Mustard Seed

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/53.1.1 ◽

1970 ◽

Vol 53 (1) ◽

pp. 1-3 ◽

Cited By ~ 1

Author(s):

Donald L Andersen

Keyword(s):

Allyl Isothiocyanate ◽

Mustard Seed ◽

Official Method ◽

Average Recovery ◽

Aoac Method ◽

Aoac Official ◽

Mustard Seeds ◽

Column Preparation ◽

Aoac Official Method

Abstract A new GLC method for the determination of allyl isothiocyanate in mustard seed was compared to a method of the Midwest Research Institute and to a combination of the AOAC official method and the proposed method. Twelve collaborators compared the AOAC method and the GLC method, using whole mustard seeds. Each collaborator assayed three seed portions by both methods. The range, standard deviation, and coefficient of variation are less for each seed portion by the proposed than by the official method. The average recovery value of allyl isothiocyanate in the prepared standard solutions is lower, using the proposed GLC procedure, but seed assay values are significantly and consistently higher for each seed portion when compared with the results for the AOAC method. Reports from the collaborators also indicate that the proposed method is rugged, as the GLC column preparation was subjected to many changes. It is recommended that the GLC method be adopted as official first action.

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Comparison of Babcock and Ether Extraction Methods for Determination of Fat Content of Cream: Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/79.4.907 ◽

1996 ◽

Vol 79 (4) ◽

pp. 907-916 ◽

Cited By ~ 2

Author(s):

Joanna M Lynch ◽

David M Barbano ◽

J Richard Fleming

Keyword(s):

Extraction Method ◽

Collaborative Study ◽

Extraction Methods ◽

Fat Content ◽

Official Method ◽

Ether Extraction ◽

Aoac Official ◽

The Difference ◽

Aoac Official Method

Abstract A modified Mojonnier ether extraction method for determination of the fat content of cream was developed based on the method for milk (AOAC Official Method 989.05). The cream Babcock method (AOAC Official Method 920.111 B-C) was modified to harmonize with the milk Babcock method (AOAC Official Method 989.04) and to clarify procedural details. Using the AOAC collaborative study format, 10 laboratories tested 9 pairs of blind duplicate heat-treated cream samples with a fat range of 30-45% using both methods. The statistical performance (invalid and outlier data removed) was as follows: mean % fat = 37.932, sr = 0.125, sR = 0.151, RSDr = 0.330, RSDR = 0.398, r = 0.354, and R = 0.427 for the ether extraction method. For the Babcock method, mean % fat = 38.209, sr = 0.209, SR = 0.272, RSDr = 0.548, RSDR = 0.712, r = 0.592, and R = 0.769. Average test results for fat from the Babcock method were 0.277% (absolute fat) greater than for the Mojonnier ether extraction method. The difference between methods, as a percentage of the average fat content of the samples, was 0.73%. This agrees with differences observed between the 2 methods for milk when 10 to 17 laboratories tested 7 milk samples in blind duplicate at bimonthly intervals over a 4-year period (average difference 0.029% fat, 0.78% as a percentage of average fat content). The Mojonnier ether extraction and Babcock methods for fat in cream have been adopted by AOAC INTERNATIONAL. The new Babcock method replaced the AOAC Official Method 920.111 B-C.

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Determination of Total Dietary Fiber in Selected Foods Containing Resistant Maltodextrin by a Simplified Enzymatic-Gravimetric Method and Liquid Chromatography: Interlaboratory Study in China

Journal of AOAC International ◽

10.1093/jaoac/91.3.614 ◽

2008 ◽

Vol 91 (3) ◽

pp. 614-621 ◽

Cited By ~ 2

Author(s):

Boqiang Fu ◽

Jing Wang ◽

Jean Michel Roturier ◽

Zhiyu Tang ◽

Huan Li ◽

...

Keyword(s):

Dietary Fiber ◽

Interlaboratory Study ◽

National Standard ◽

Official Method ◽

Total Dietary Fiber ◽

Modified Method ◽

Resistant Maltodextrin ◽

Aoac Official ◽

Aoac Official Method

Abstract An interlaboratory study was conducted in China to validate the modified AOAC Official Method 2001.03 for the determination of total dietary fiber (TDF) in foods containing resistant maltodextrin (RMD), which will be adopted as the National Standard Method of China. The kind of buffer solution, the volume of filtrate evaporation, the volume of eluent for desalting and residual solution after evaporation, etc. were modified, which had been proved to have acceptable accuracy and precision in the routine assay. TDF contents in 3 representative foods and 2 kinds of RMD ingredient (i.e., NUTRIOSE 06 and NUTRIOSE 10) were measured using the modified method in 6 eligible laboratories representing commercial, industrial, and governmental laboratories in China. The results of the interlaboratory study indicated that the intralaboratory repeatability, interlaboratory reproducibility, and precision of the modified method are adequate for reliable analysis of TDF in food containing RMD, as well as resistant dextrin. Compared to AOAC Official Method 2001.03, the modified method is time- and cost-saving.

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Liquid Chromatographic Determination of Pyrantel Tartrate in Medicated Formulations

Journal of AOAC International ◽

10.1093/jaoac/86.5.882 ◽

2003 ◽

Vol 86 (5) ◽

pp. 882-887

Author(s):

Joyce A Konrardy ◽

Mary A Burner ◽

Tommy W Garner ◽

Mark A Litchman ◽

Gregory K Webster

Keyword(s):

Chromatographic Determination ◽

Official Method ◽

Stability Indicating ◽

Stability Indicating Method ◽

Liquid Chromatographic Determination ◽

Aoac Official ◽

Liquid Chromatographic ◽

Aoac Official Method ◽

Pyrantel Tartrate

Abstract The validation of a novel liquid chromatographic (LC) method for the determination of pyrantel tartrate in feed is presented. The method provides a significant improvement over the efficiency and precision of AOAC Official Method 978.30. The method was shown to be accurate, precise, linear, and robust for medicated articles. Unlike the official method, the LC method was shown to be a superior stability-indicating method. After the method was validated by using laboratory blends, the effectiveness of the method was demonstrated with marketed product as well.

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Determination of Formaldehyde in Maple Sirup: Interfering Substances

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/55.1.121 ◽

1972 ◽

Vol 55 (1) ◽

pp. 121-122

Author(s):

J C Underwood

Keyword(s):

Mass Spectrometry ◽

Carbonyl Compounds ◽

Official Method ◽

Formaldehyde Determination ◽

Aoac Official ◽

Aoac Official Method

Abstract Three carbonyl compounds isolated from maple sirup by distillation as in the AOAC official method for formaldehyde have been identified by mass spectrometry as formaldehyde, acetone, and acetaldehyde. Acetone and acetaldehyde do not interfere with the formaldehyde determination if the procedure of the AOAC official method is followed; acetol and glyoxal also do not cause errors in the formaldehyde value. Tests run have shown the modified Nash method (31.184–31.189) adopted as official final action to be extremely specific for formaldehyde in maple sirup.

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Single-Laboratory Validation of AOAC Official Method 2011.10 for Vitamin B12 in ‘Indian’ Infant and Pediatric Formulas and Adult Nutritionals

Journal of AOAC International ◽

10.5740/jaoacint.19-0199 ◽

2020 ◽

Vol 103 (1) ◽

pp. 3-8

Author(s):

Priti N Amritkar ◽

Laxman Gujar ◽

Ashutosh Kumar Mittal ◽

Anand Sheshadri ◽

Rajesh Girdhar ◽

...

Keyword(s):

Vitamin B12 ◽

Water Soluble ◽

Official Method ◽

Relative Standard ◽

Aoac Method ◽

Aoac Official ◽

Indian Infant ◽

Single Laboratory ◽

Aoac Official Method

Abstract Background: Ensuring the quality of infant and pediatric formulas and adult nutritionals is of utmost importance for the health and safety of rapidly urbanizing Indian population. B12 is an important water-soluble vitamin, which is fortified externally in such nutritional formulations. The Bureau of Indian Standards (BIS) has a recommended microbiological assay–based method for determination of vitamin B12 that is not precise and accurate enough to meet the label claim requirements of infant, adult, and/or pediatric nutritionals. The AOAC Official Method 2011.10 was originally developed under the AOAC Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) for the determination of vitamin B12 in infant and pediatric formulas and adult nutritionals. However, those SPIFAN matrixes did not contain malt and other indigenous cereal and legume flour (with or without cocoa powder), which are commonly found in Indian formulations. Thus, there is a need to replace this method with a more precise and accurate method. Objective: This study was undertaken to validate the AOAC Official Method 2011.10 on vitamin B12 in ‘Indian’ infant and pediatric formulas and adult nutritionals. Methods: The single-laboratory validation (SLV) of AOAC Method 2011.10 was carried out as per the AOAC Guidelines in six Indian pediatric and adult nutritional formulas to verify its fitness for purpose. Cobalamin in the sample was converted to cyanocobalamin on treatment with potassium cyanide. The sample was then subjected to clean up through a C18 cartridge. Vitamin B12 in the eluted extract was separated from other components using size-exclusion column chromatography followed by a C18 column. The HPLC analysis was carried out at 550 nm. Results: Diastase treatment and C18 solid-phase extraction cleanup satisfactorily removed the matrix interference. The relative standard deviation of the determined values in 30 samples each from 6 selected Indian products and NIST SRM 1849a was <20%. The average recoveries for the spiked recovery samples ranged from 91.75 to 101.14%. Conclusions: Method 2011.10 met the standard method performance requirements set forth by the AOAC SPIFAN. Therefore, we recommend the Method 2011.10 for adoption as the BIS official method for the analysis of vitamin B12 in ‘Indian’ infant and pediatric formulas and adult nutritionals. Highlights: This was the first SLV project that the AOAC India section undertook to extend the scope of the AOAC Method 2011.10 for vitamin B12 analysis by validating it in ‘Indian’ infant and pediatric formulas and adult nutritionals.

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Refinement of AOAC Official MethodSM 2005.06 Liquid Chromatography-Fluorescence Detection Method to Improve Performance Characteristics for the Determination of Paralytic Shellfish Toxins in King and Queen Scallops

Journal of AOAC International ◽

10.5740/jaoacint.11-184 ◽

2012 ◽

Vol 95 (1) ◽

pp. 129-142 ◽

Cited By ~ 28

Author(s):

Andrew D Turner ◽

Robert G Hatfield

Keyword(s):

Fluorescence Detection ◽

Periodate Oxidation ◽

Performance Characteristics ◽

Official Method ◽

Refined Method ◽

Paralytic Shellfish ◽

Aoac Official ◽

Psp Toxins ◽

Aoac Official Method

Abstract AOAC Official MethodSM 2005.06 LC-fluorescence detection (FLD) method is an official alternative to the mouse bioassay for the determination of paralytic shellfish poisoning (PSP) toxins in bivalve shellfish. To validate the method for species of relevance to the UK official control monitoring program, the method performance characteristics were tested for whole king and queen scallops. Validation showed that, while the performance was generally acceptable for the quantitation of non-N-hydroxylated toxins, poor toxin recovery and sensitivity was evident for the analysis of N-hydroxylated toxins following periodate oxidation. These effects occurred in a range of scallop samples with variable temporal and spatial sources. The effects were also noted in other laboratories following a small interlaboratory study. As a result, the method was refined to improve the recovery and sensitivity of analysis following the periodate oxidation step in the PSP method for scallops. Performance improved through alterations to the preparation of the periodate oxidant, use of higher volumes for C18 cleanup, and injection volumes in combination with the use of a king scallop matrix modifier for oxidation of N-hydroxylated toxin calibration standards. A single-laboratory validation of the refined method showed that the selectivity, linearity, sensitivity, recovery, and precision were acceptable and similar to values reported previously for AOAC Official Method 2005.06 in other bivalve species. Results showed the method to be rugged for all parameters investigated, including small changes to the composition of the new periodate reagent utilized in the refined method. The refined scallops LC method was subsequently compared with the European reference method. PSP-positive scallops showed an excellent agreement between the methods for queen and Atlantic scallops, with a small level of positive bias in the LC results for whole king scallops. These differences were related solely to the use of the highest toxicity equivalence factors for toxin epimeric pairs, with gonyautoxin (GTX)1,4 and GTX2,3 in particular present at high concentrations in the king scallops. Overall, the refined LC-FLD method improved the performance characteristics of AOAC Official Method 2005.06 for the determination of PSP toxins in whole king and queen scallops, and showed a good overall agreement between the official methodologies. It is, therefore, recommended as a more appropriate option for the routine monitoring of PSP toxins in these species.

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Ion Chromatographic Determination of Nitrate and Nitrite in Vegetable and Fruit Baby Foods

Journal of AOAC International ◽

10.1093/jaoac/88.6.1793 ◽

2005 ◽

Vol 88 (6) ◽

pp. 1793-1796 ◽

Cited By ~ 25

Author(s):

Sarah E McMullen ◽

John A Casanova ◽

Lois K Gross ◽

Frank J Schenck

Keyword(s):

Chromatographic Determination ◽

Official Method ◽

Anion Exchange Column ◽

Baby Foods ◽

Suppressed Conductivity Detection ◽

Method Yield ◽

Aoac Official ◽

Nitrate And Nitrite ◽

Aoac Official Method

Abstract An ion chromatographic method was developed for the determination of nitrate and nitrite in vegetable and fruit baby foods. The introduction of nitrate or nitrite to food may be natural or artificial as a preservative. Because of the higher pH found in babies' stomachs, nitrate can act as a reservoir for the production of nitrite by nitrate-reducing bacteria that can be harbored in the intestinal tract. This problem does not exist in adults because of the lower pH of the adult stomach. Exposure to nitrite by infants can result in methemoglobinemia (blue baby syndrome). There are also indications that carcinogenic nitrosamines can be formed from nitrates at the higher pH. These gastric conditions disappear at approximately 6 months of age. In this method, nitrate and nitrite were separated on a hydroxide-selective anion exchange column using online electrolytically generated high-purity hydroxide eluant and detected using suppressed conductivity detection. Average recoveries of spiked nitrite residue ranged from 91 to 104% and spiked nitrate residue ranged from 87 to 104%. This method and the AOAC Official Method yield comparable results for samples containing incurred nitrate residue. In addition, this method eliminates the hazardous waste associated with the use of cadmium found in the AOAC Official Method.

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Extension of AOAC Official Method 999.14 (Choline in Infant Formula and Milk) to the Determination of Choline in Dietary Supplements

Journal of AOAC International ◽

10.1093/jaoac/87.6.1297 ◽

2004 ◽

Vol 87 (6) ◽

pp. 1297-1304 ◽

Cited By ~ 5

Author(s):

Jeanne I Rader ◽

Carol M Weaver ◽

Mary W Trucksess

Keyword(s):

Dietary Supplements ◽

Dietary Supplement ◽

Infant Formula ◽

Sole Source ◽

Official Method ◽

Standard Curve ◽

Liquid Products ◽

Aoac Official ◽

Aoac Official Method

Abstract AOAC Official Method 999.14 is applicable for the determination of choline in milk and infant formulas. To date, its use has not been extended beyond these matrixes. We modified Official Method 999.14 and applied it to the determination of choline in a range of choline-containing dietary supplements. Dietary supplement tablets, capsules, wafers, softgels, liquid products, and drink powders were included. We found that the standard curve could be extended to cover a wider range of choline concentrations and defined a procedure for the use of Norit for samples in which the vitamin C content was high enough to interfere with the analysis. Recoveries of choline added to infant formula powders and to representative dietary supplement tablets, capsules, powdered drink mix, and wafer products were 85–114%. The use of Norit during the procedure did not affect the recovery of choline added to infant formula powders or to dietary supplements. An alkaline digestion was included for use with a product containing lecithin as the sole source of choline.

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