Modification and Single-Laboratory Validation of AOAC Official Method 977.13 for Histamine in Seafood to Improve Sample Throughput

2015 ◽  
Vol 98 (3) ◽  
pp. 622-627 ◽  
Author(s):  
Kristin Bjornsdottir-Butler ◽  
F. Aladar Bencsath ◽  
Ronald A. Benner, Jr

Histamine is the main causative agent in scombrotoxin fish poisoning, the most frequently reported illness related to fish consumption. The AOAC official method for histamine determination in fish is the fluorometric method AOAC 977.13, which is sensitive and reproducible but somewhat labor intensive and time consuming. We investigated multiple modifications to this method in an attempt to reduce assay time and increase sample throughput while maintaining the performance of the original method. Some of the attempted modifications negatively affected the performance characteristics of the method. However, omitting the heating step during extraction and replacing the cuvette style fluorometer with a microplate reader retained method performance while increasing sample throughput. Therefore, we adopted these modifications and conducted a single-laboratory validation. The recovery, precision (RSD), and LOD of the modified method assessed by the single-laboratory validation ranged from 92 to 105%, 1 to 3%, and 0.2 to 0.5 ppm, respectively, in tuna, mahi-mahi, and Spanish mackerel samples. We conclude that the AOAC 977.13 fluorometric method, modified as described, will improve assay time and sample throughput efficiency cumulatively, as the number of sample units analyzed increases. We anticipate that this modified method could be used by regulatory agencies and other laboratories following successful multilaboratory validation.

1970 ◽  
Vol 53 (1) ◽  
pp. 3-6
Author(s):  
R. Bruce Klemm ◽  
Mary E. Ambrose Klemm

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.


2008 ◽  
Vol 91 (3) ◽  
pp. 614-621 ◽  
Author(s):  
Boqiang Fu ◽  
Jing Wang ◽  
Jean Michel Roturier ◽  
Zhiyu Tang ◽  
Huan Li ◽  
...  

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.


1996 ◽  
Vol 79 (4) ◽  
pp. 1012-1017 ◽  
Author(s):  
Gregory K Webster ◽  
Rostyk Mandzu ◽  
Lisa A Drong ◽  
William H Williams ◽  
Brian G Mess ◽  
...  

Abstract AOAC Official Method 971.47 was optimized for use with solid-phase extraction (SPE) using the same activated carbon referenced in the original method. The optimization of AOAC 971.47 begins after the roxarsone is extracted into the 2% K2HPO4 solution of the original method; instead of 30 mL, 9 mL is pipetted into a test tube. Next, to flocculate the protein, 300 μL HCI is pipetted into the tube and mixed. After 15 min, the contents of the tube are filtered through a 0.45 μm nylon membrane filter equipped with a glass prefilter. Next, 7 mL clear filtrate is pipetted into a new test tube, followed by the addition of 234 μL NaOH, and the contents of the tube are mixed. The filtrate is then passed through a 400 mg bed of activated carbon packed in a 3 mL SPE tube at a flow rate of 1 mL/min. The spectrophotometric analysis of the eluate is not changed from the original AOAC 971.47. The optimized method was validated and semiautomated. Results of roxarsone determination by the optimized procedure were found to be acceptable at all levels of approved claims. For the commercial feed samples analyzed, recoveries by the automated method ranged from 93.7 to 104% of the results reported by an independent laboratory using AOAC 971.47.


1983 ◽  
Vol 66 (1) ◽  
pp. 118-122
Author(s):  
Kate Wiggin ◽  
Judith Krzynowek

Abstract A modification of the AOAC official method for generic identification of cooked and frozen crabmeat was investigated in an experiment in which the cooked meats of a variety of shellfish were identified. The modification, substituting agarose for polyacrylamide as the gel medium, has many advantages over the official method, including ease of gel preparation, nontoxic reagents, and rapid focusing. Results indicate that the modified method is easier to use and that identifications of cooked shellfish species can be made as readily as with the current AOAC method.


2014 ◽  
Vol 97 (1) ◽  
pp. 166-172 ◽  
Author(s):  
Philip R Machonis ◽  
Matthew A Jones ◽  
Catherine Kwik-Uribe

Abstract Recently, a multilaboratory validation (MLV) of AOAC Official Method 2012.24 for the determination of cocoa flavanols and procyanidins (CF-CP) in cocoa-based ingredients and products determinedthat the method was robust, reliable, and transferrable. Due to the complexity of the CF-CP molecules, this method required a run time exceeding 1 h to achieve acceptable separations. To address this issue, a rapid resolution normal phase LC method was developed, and a single-laboratory validation (SLV) study conducted. Flavanols and procyanidins with a degree of polymerization (DP) up to 10 were eluted in 15 min using a binary gradient applied to a diol stationary phase, detected using fluorescence detection, and reported as a totalsum of DP 1–10. Quantification was achieved using (-)-epicatechin-based relative response factors for DP 2–10. Spike recovery samplesand seven different types of cocoa-based samples were analyzed to evaluate the accuracy, precision, LOD, LOQ, and linearity of the method. The within-day precision of the reported content for the samples was 1.15–5.08%, and overall precision was 3.97–13.61%. Spike-recovery experiments demonstrated recoveries of over 98%. The results of this SLV were compared to those previously obtained in the MLV and found to be consistent. The translation to rapid resolution LC allowed for an 80% reduction in analysis time and solventusage, while retaining the accuracy and reliability of the original method. The savings in both cost and time of this rapid method make it well-suited for routine laboratory use.


2020 ◽  
Vol 103 (1) ◽  
pp. 3-8
Author(s):  
Priti N Amritkar ◽  
Laxman Gujar ◽  
Ashutosh Kumar Mittal ◽  
Anand Sheshadri ◽  
Rajesh Girdhar ◽  
...  

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.


2020 ◽  
Vol 103 (2) ◽  
pp. 489-493 ◽  
Author(s):  
Elizabeth M Mudge ◽  
Paula N Brown

Abstract Background Legalization of Cannabis across many U.S. states and in Canada had led to an urgent need for validated analytical methods for the quantitation of cannabinoids in Cannabis sativa L. flowers and finished products. The AOAC Stakeholder Panel on Strategic Food Analytical Methods Cannabis Expert Review Panel (ERP) approved an HPLC-diode-array detection (DAD) method for First Action Official MethodsSM status. Objective To present Official Methods of AnalysisSM (OMA) 2018.10 method details, validation results, and additional method extension data as approved by the ERP and further requirements for Final Action Official MethodsSM status. Methods This previously published method used 80% aqueous methanol via sonication for extracting eight cannabinoids—tetrahydrocannabidiolic acid, tetrahydrocannabinol, cannabidiolic acid, cannabidiol, tetrahydrocannabivarin, cannabigerol, cannabinol, and cannabichromene—in dried flowers followed by reversed-phase chromatographic separation and UV detection. Results The original method underwent extensive method optimization and a single-laboratory validation. Additional requirements requested by the Standard Method Performance Requirement (SMPR®) included a method extension, which was performed to collect repeatability data on two additional cannabinoids: cannabidivarinic acid and cannabigerolic acid. The methods performance was compared with the AOAC SMPR 2017.002 and 2017.001. RSDr ranged from 0.78 to 10.08% and recoveries from 90.7 to 99.2% in several different chemotypes. Conclusions The ERP adopted the method and provided recommendations for achieving Final Action status. Highlights After submission of additional validation data, an HPLC-DAD method for quantitation of cannabinoids in dried flowers and oils was accepted for First Action Official Method status (OMA 2018.10).


2019 ◽  
Vol 102 (2) ◽  
pp. 673-676
Author(s):  
Naoto Hieda ◽  
Yoshihiro Ikeuchi ◽  
Ichirou Matsuno

Abstract Background: Reliable measurements of iodine are essential for ensuring the qualityof infant formula. The AOAC Official Method 2012.15 for iodine tends to produce higher results in the presence of carbon remaining in the final test solution after digestion with alkaline dissolution. This is partly because of the lack of countermeasures for signal enhancement induced by coexisting carbon in Method 2012.15. Objective: To obtain more reliable values for infant formulas, we undertook an experiment. Methods: We modified the protocol by addingcarbon in the form of methanol to both the standardsolutions and the final test solutions. Comparisonsof the enhancement factor for iodine-127 were usedto find the optimized concentration of methanol from0–10%. Results: Optimization of the additional carbon showed that a 5% methanol minimum was necessary for a constant ratio of iodine. The results exhibited good linearity (coefficient of determination >0.999), and the LOQ was 0.19 μg/100 g for the reconstituted final product with a methanol concentration of 5%. The intermediate precision RSD was <3.76%, and the recovery factor was 97.5–104.2% for infant formula distributed in several countries and a special formula distributed in Japan. Conclusions: This demonstrates that 5% methanol, when addedto standard and final solutions, acts as an effective matrix matching agent. Highlights: This modified method produces more accurate iodine quantification in infant formulas and special formulas in which there is incomplete digestion of the matrix.


1997 ◽  
Vol 80 (3) ◽  
pp. 591-602 ◽  
Author(s):  
Patricia L Rogers ◽  
Walter Staruszkiewicz ◽  
A Adams ◽  
B Atienza ◽  
R J Berg ◽  
...  

Abstract A collaborative study was conducted to test a modification to the AOAC fluorometric method for histamine (AOAC® Official Method 977.13) that substitutes 75% methanol as the extracting solvent. All other steps remain unchanged. The extracts prepared with 75% methanol were also used to collaboratively test a gas chromatographic (GC) method for determination of putrescine and cadaverine in seafood. In the GC method, the extracted diamines are converted to fluorinated derivatives, the reaction mixtures are passed through solid-phase extraction columns, and the derivatives are quantitated by electron capture GC after separation on an OV-225 column. Fourteen laboratories using the GC method for putrescine and cadaverine and 16 laboratories using the fluorometric method for histamine analyzed 14 canned tuna and raw mahimahi (including blind duplicates and a spike) containing 0.2-2.6 ppm putrescine, 0.6-9.1 ppm cadaverine, and 0.6-154 ppm histamine. At the 5 ppm level, recoveries ranged from 71 to 102% for putrescine and 77 to 112% for cadaverine; the respective repeatability relative standard deviations (RSDr) were 5.2 and 15%, and the respective reproducibility relative standard deviations (RSDR) were 8.8 and 18%. At the 50 ppm level, histamine recoveries ranged from 84 to 125%, RSDr was 3.6%, and RSDR was 9.4%. The GC method for determination of putrescine in canned tuna and cadaverine in canned tuna and mahimahi has been adopted first action by AOAC INTERNATIONAL, and the AOAC Official Method 977.13, Histamine in Seafood, Fluorometric Method, has been modified


2002 ◽  
Vol 85 (3) ◽  
pp. 676-681
Author(s):  
Mark Wheeler Wheeler ◽  
Barbara Bennett ◽  
Harry Marks

Abstract A procedural modification of the AOAC Official Method for extracting light filth from ground oregano and ground marjoram was tested in an intralaboratory study. The modified method specifies isopropanol defatting, 975.49A(a), rather than chloroform–isopropanol defatting, 975.49A(b), followed by direct flotation as directed in AOAC Official Method, 975.49B(b). The modified method provided comparable results in less time while also providing safety, health, and financial benefits.


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