bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of the Iodine Value of Oils and Fats: Summary of Collaborative Study
Authors: Firestone David 
Published: February 2020

Abstract
Two collaborative studies were conducted using the Wijs method for determining the iodine value in a wide range of vegetable and animal oils and fats. The results obtained when using carbon tetrachlo-ride were compared to those obtained when using a substitute solvent mixture of cyclohexane and glacial acetic acid. The values reported for the iodine values indicate that the cyclohexane and acetic acid mixture can be used in place of carbon tetrachloride without loss of precision. The method has been adopted first action by AOAC INTERNATIONAL as an IUPAC/AOCS/AOAC method.
Determination of Total Dietary Fiber in Foods and Products with Little or No Starch, Nonenzymatic-Gravimetric Method: Collaborative Study
Authors: Li Betty W , Cardozo Maria S 
Published: February 2020

Abstract
A collaborative study was conducted to validate a nonenzymatic-gravimetric method for the determination of total dietary fiber (TDF) of samples containing little or no starch such as most fruits, and vegetables and many purified polysaccharides. This simple procedure involves suspension of freeze-dried, ground samples in deionized water and incubation at 37°C for 90 min, followed by pre-cipitation with 4 volumes of 95% ethanol. The weight of the dilute alcohol-insoluble residues after correcting for crude protein and ash corresponds to the TDF content of the sample. Six samples in blind duplicate (apples, apricots, cabbage, carrots, onions, and soy fiber) were sent with Celite to 10 laboratories. The reproducibility relative standard deviation (RSDr) of the TDF values for 9 laboratories ranged from 2.92 to 6.25%. The repeatability standard deviation (RSDr) for the 9 laboratories ranged from 1.50 to 2.70%. The method has been adopted first action by AOAC INTERNATIONAL.
Simple and Rapid Determination of Phytase Activity
Authors: Engelen Adrianus J , Van Der Heeft Fred C , Randsdorp Peter H G , Smtt Ed L C 
Published: February 2020

Abstract
A simple and rapid method is described for determining the enzymatic activity of microbial phytase. The method is based on the determination of inorganic orthophosphate released on hydrolysis of sodium phytate at pH 5.5.
Comparison of Direct Extraction and AOAC Official Methods for Available P2O5 in Fertilizers: Collaborative Study
Authors: Gliksman Joseph E 
Published: February 2020

Abstract
Fifteen fertilizer samples were sent to 13 laboratories for determination of available P2O5. Eleven laboratories, including author's laboratory, completed the analyses. Each sample was analyzed twice for available P2O5 by the new direct extraction method, and by either of the AOAC Official Methods using direct or indirect extraction. Results were favorable for the new direct extraction method even though the range and types of samples were highly variable. The direct extraction method was adopted first action by AOAC INTERNATIONAL.
Determination of Dephosphate Bromofenofos in Milk by Liquid Chromatography with Electrochemical Detection
Authors: Takeba Kazue , Itoh Takeshi , Matsumoto Masao , Nakazawa Hiroyuki 
Published: February 2020

Abstract
A sensitive, specific method for the determination of dephosphate bromofenofos (DBFF) in milk by liquid chromatography (LC) with electrochemical detection is described. DBFF, the only metabolite of bromofenofos (BFF, a fasciolicide), was extracted from milk by liquid–liquid partition with acetone, acetonitrile, and dichloromethane and purified by using a C18 cartridge. The compound was separated from the matrix peaks by reversed-phase LC and detected by dual-electrode coulometric detection on a Kaseisorb LC ODS-300-5 (250 × 4.6 mm id, 5 μm) column. The mobile phase was acetonitrile–0.05M potassium dihydrogen phosphate (55 + 45, v/v) at pH 3.0. The flow rate was 1 mL/min at 40°C. The applied potentials of detectors 1 and 2 were maintained at 0.30 and 0.45 V, respectively. Average recoveries (n = 5) of DBFF from milk spiked at 1 and 10 ng/mL were 73.1 and 82.7%, respectively; and coefficients of variation were 8.4 and 2.8%, respectively. The detection limit of DBFF in milk was 0.2 ng/mL. Fifty-nine raw and 181 commercial milks were analyzed. DBFF was detected in 4 raw milks (0.2–1.5 ng/mL; average, 0.6 ng/mL) and in 3 normal liquid commercial milks (0.3–0.7 ng/mL; average, 0.5 ng/mL). The identity of DBFF from milk was confirmed by gas chromatography/mass spectrometry.
Update on Validation of Microbiological Methods by AOAC INTERNATIONAL
Authors: Andrews Wallace H 
Published: February 2020

Abstract
An update is presented of the microbiological methods validated by AOAC since 1983. A sequential listing of the microbiological methods adopted first action between 1939 and 1993 gives the permanent new numbers of each, as introduced in Official Methods of Analysis, 15th Edition. Consideration is given to the expanded applicability of approved methods with respect to food matrix; the predominance of methods for the detection, identification, and serological testing of Salmonella spp.; and the procedures for coliforms and Escherichia coli, which were most frequently approved between 1973 and 1993. The substantial increase in validation of test kits is discussed, and categories of methods for the modification of test kits already approved are defined.
Extraction of Light Filth from Whole Wheat Flour, Flotation Method: Collaborative Study
Authors: Glaze Larry E , Bryce John R 
Published: February 2020

Abstract
An additional extraction/flotation method for the determination of light filth in whole wheat flour was validated through a collaborative study. A 50 g test portion is boiled in a 3% HCI solution. The mixture is washed with hot tap water on a No. 230 sieve. Then the residue is boiled in iso-propanol, transferred to a No. 230 sieve, and washed again. The residue is transferred to a Wildman trap flask using 40% isopropanol. The filth is isolated by flotation in mineral oil and a mixture of Tween 80 and Na4EDTA in 40% isopropanol. Average recoveries by 8 collaborators were 88.8 and 91.7% for insect fragments and rat hairs, respectively. The extraction/flotation method for determination of light filth in whole wheat flour has been adopted first action by AOAC INTERNATIONAL as an additional procedure to the AOAC Official Method 941.16, Filth in Grain Products.
Application of Gas Chromatography/Matrix Isolation/Fourier Transform Infrared Spectroscopy to the Identification of Pyrrolizidine Alkaloids from Comfrey Root (Symphytum officinale L.)
Authors: Mossoba Magdi M , Lin Hubert S , Andrzejewski Denis , Sphon James A , Betz Joseph M , Miller Lee J , Eppley Robert M , Trucksess Mary W , Page Samuel W 
Published: February 2020

Abstract
This paper demonstrates that pyrrolizidine alkaloids (PAs) extracted from comfrey root grown in Washington State (USA) can be identified by gas chromatography/matrix isolation/Fourier transform infrared (GC/MI/FTIR) spectroscopy. Infrared spectral bands observed in the fingerprint region were unique even for closely related structures. The identities of the 4 major components, intermedine, lycopsamine, 7-acetylintermedine, and 7-acetylly-copsamine, were confirmed by comparison with standards. Confirmation was also obtained by using the established techniques of electron ionization and positive ion chemical ionization gas chro-matography/mass spectrometry. The infrared spectra observed for the components of the root extract were consistent with known structures of specific PAs. The identities of the minor components, sym-phytine and its isomers symlandine and/or sym-viridine, in the same extract were not confirmed.
Determination of Cholinesterase Activity in Brain and Blood Samples Using a Plate Reader
Authors: Tor Elizabeth R , Holstege Dirk M , Galey Francis D 
Published: February 2020

Abstract
A rapid method is described for the quantitative determination of cholinesterase activity in large batches of blood and brain samples. The technique is an adaptation of the Ellman procedure for a 96-well microtiter plate reader. Ten samples can be analyzed simultaneously in 5 min, with all calculations, including statistical analysis, done automat- ically. The method detection limit is 0.1 μM/mL/min for blood and 0.1 μM/g/min for brain samples. The procedure has been applied to the routine analyses of samples presented to the veterinary diagnostic laboratory. Method performance, quality control, and normal ranges of cholinesterase activity in live- stock and other animals are described.
Enzyme-Linked Immunoassay for Detection of Listeria monocytogenes in Dairy Products, Seafoods, and Meats: Collaborative Study
Authors: Curiale Michael S , Lepper Wendy , Robison Barbara 
Published: February 2020

Abstract
A collaborative study was conducted to evaluate Listeria-TekTM, an enzyme-linked immunosorbent assay (ELISA) for detection of Listeria monocytogenes and other Listeria spp. in foods. The present ELISA method was compared to the U.S. Food and Drug Administration culture method for detection of L. monocytogenes in dairy products and seafoods and to the U.S. Department of Agriculture Food Safety and Inspection Service method for detection of L. monocytogenes in meats. Replicate samples of 6 food types (frankfurters, roast beef, Brie cheese, 2% milk, raw shrimp, and crab meat) inoculated with L. monocytogenes and uninoculated control samples were analyzed by the collaborators. L. monocytogenes was identified in 593 samples by the ELISA method and in 574 samples using culture procedures. Identical results were obtained for 506 positive samples and 419 negative samples using the ELISA and culture methods for an overall agreement rate of 85.6%. The enzyme-linked immunoassay for detection of L. monocytogenes in dairy, seafood, and meat products has been adopted first action by AOAC INTERNATIONAL.
Multifunctional Column Coupled with Liquid Chromatography for Determination of Aflatoxins B1, B2, G1, and G2 in Corn, Almonds, Brazil Nuts, Peanuts, and Pistachio Nuts: Collaborative Study
Authors: Trucksess Mary W , Stack Michael E , Nesheim Stanley , Albert Richard H , Romer Thomas R 
Published: February 2020

Abstract
An AOAC/IUPAC collaborative study was conducted to evaluate the effectiveness of a multifunctional column for the determination of aflatoxins. The test portion is extracted with acetonitrile–water (9 + 1), the extract is filtered, and the filtrate is passed through the column. The aflatoxins in the eluate are determined by reversed-phase liquid chromatography after derivatization with trifluoroacetic acid. Naturally contaminated corn, almonds, Brazil nuts, peanuts, and pistachio nuts spiked with total aflatoxins at 5,10,20, and 30 ng/g were sent to 12 collaborators in the United States, Denmark, France, Japan, and Switzerland. Eleven collaborators completed the study. Average recoveries of total aflatoxins for each spike level for the various commodities (excluding Brazil nuts at 5 ng/g) were 93,97,95, and 95%, respectively; the repeatability relative standard deviation (RSDr) ranged from 6.0 to 23.2% and the reproducibility relative standard deviation (RSDR) ranged from 12.0 to 69.4%. The multifunctional column coupled with a liquid chromatographic method for determination of aflatoxins in corn, almonds, Brazil nuts, peanuts, and pistachio nuts has been adopted first action by AOAC INTERNATIONAL.
Rapid Screening of Pharmaceuticals by Thin-Layer Chromatography: Analysis of Essential Drugs by Visual Methods
Authors: Kenyon Allen S , Flinn Paul E , Layloff Thomas P 
Published: February 2020

Abstract
A method for rapidly screening pharmaceuticals by thin-layer chromatography has been designed for use in areas with limited resources and by operators with limited training. An apparatus for performing the analysis in a plastic bag under equilibrium conditions was designed. Results can be reproduced by different operators and in different locations. The analysis can be performed without electricity or in a remote area, away from a laboratory. It is especially suited for field use in developing countries. The method is low cost, maintenance-free, fast, and reliable; it also uses limited volumes of solvents. The analyses can be performed without weighing if reference materials can be supplied in tablet form, provided the drug content is listed and only one unit is required for each analysis. All procedures were developed for the analysis of drugs from a partial list of essential drugs established by the World Health Organization. Three drugs were selected and prepared in the form of reference tablets. Comparisons with the analyses of the drugs in standard dosage forms were made by using reference tablets and primary USP standards. Comparable results were obtained, proving that the screening process can be conducted by using reference tablets and without weighing either the sample or the reference. The method has been successfully demonstrated and used in Swaziland, by high school teachers in the United States, and by personnel from the Ministry of Health in Saudi Arabia. Personnel can be trained in a short time to perform screening analysis of drugs.
Determination of pH of Soils by Different Methods: Collaborative Study
Authors: Kalra Yash P 
Published: February 2020

Abstract
Fifty-three laboratories (including author’s) from Canada, India, Israel, and the United States participated in a collaborative study for the measurement of pH of different types of soils. A method with 2 alternative procedures was used for pH measurements of mineral soils (alternative I for soils containing less than 17⋊ organic carbon and alternative II for soils with variable salt content), a second method was used for saline-sodic soils, and a third method was used for organic soils (soils containing at least 17⋊ organic carbon). The pH was measured potentiometricaIly. The methods were selected by the Soil Science Society of America, S889 Committee on Coordination of Official Methods of Soil Analysis. Each laboratory used all 4 procedures to analyze 10 blind duplicate samples per procedure. The repeatability relative standard deviation values (RSDr) were 1.45–7.80% for mineral soils tested by the alternative 1,0.95–6.91% for mineral soils tested by the alternative II, 0.74–7.09% for saline-sodic soils, and 0.73–4.66% for organic soils. The corresponding reproducibility relative standard deviation (RSDR) values were 2.67–10.75%, 2.03–7.54%, 2.45–9.93%, and 2.15–6.32%. Repeatability and reproducibility data indicated that the results are within acceptable levels. The 3 methods for pH measurements of mineral, saline-sodic, and organic soils were adopted first action by AOAC INTERNATIONAL.
Babcock Bottle Certification Appparatus Performance Evaluation
Authors: Lynch Joanna M , Barbano David M , Houghton George , Fleming J Richard 
Published: February 2020

Abstract
The use and performance of a computer-controlled apparatus for certification of Babcock bottles used for payment testing were evaluated. The apparatus delivered mercury into the bottle neck using a syringe mounted on a motorized pump. Syringe movement and the collection and calculation of data were controlled by computer. The apparatus was evaluated using four 8% milk bottles (total volume 1.600 mL; bottles rejected if deviation was ≥0.008 mL) and four 50% short-neck cream bottles (total volume 5.000 mL; bottles rejected if deviation was ≥0.050 mL). Six milk and 5 cream bottle trials were conducted; each bottle was read 5 consecutive times for each trial. As a percentage of the rejection criteria, average repeatability was 5–6% and reproducibility was 9–10%. These values were similar for both types of bottles. The evaluation of the apparatus demonstrated acceptable within- and between- days performance in relation to the rejection criteria and volumes measured. Because the apparatus creates a closed system during certification, an additional experiment was conducted with 50% short-neck cream bottles to determine the effect of internal pressure within a bottle on volume estimates. Four trials were conducted, as previously described, using 4 control and 4 experimental bottles. Volume between the 0 and 50% marks (5 mL) was determined. Holes were drilled in the experimental bottles to eliminate internal pressure for the final 2 trials. The estimated volume of bottles under pressure was 0.0054 ± 0.0012 mL greater than without internal pressure (i.e., about 11% of the rejection criteria). We concluded that any pressure effect was small relative to other factors that affect volume determination.
Detection of Bixin, Lycopene, Canthaxanthin, and β-Apo-8′-Carotenal in Products Derived from Red Pepper
Authors: Mínguez-Mosquera M Isabel , Hornero-Méndez Dámaso , Garrido-Fernández Juan 
Published: February 2020

Abstract
An analytical method using either thin layer or liquid chromatography is proposed for the detection of 4 pigments (bixin, lycopene, canthaxanthin and (β-apo-8′-carotenal) that can be used fraudulently to intensify the natural color of products derived from red pepper (oleoresins, paprika, paprika paste, etc.)- Similarly, the addition of other colorant natural products containing some of these pigments as major pigments (such as tomato for lycopene and Bixa orellana seeds for bixin) can be detected. The method proposed can also be used to control the aforementioned pigments in their natural sources as well as in food products.
Postcolumn Derivatization Liquid Chromatographic Method for Paralytic Shellfish Toxins
Authors: Oshima Yasukatsu 
Published: February 2020

Abstract
More than 20 analogues of saxitoxin occur naturally. An accurate analytical method applicable to all saxitoxins is required because of the recent findings that decarbamoyl toxins and C (N-sulfocarbamoyl- 11-hydroxysulfate) toxins are metabolites of marine animals or major products of some dinoflagellate species. Almost all the toxins could be determined by ion-interaction chromatography on a silica-based reversed-phase (C8) column with postcolumn periodate oxidation and fluorescence detection. Toxin groups of different net charges were separately determined by isocratic elution using different mobile phases. For determination of the saxitoxin group (net charge, 2+) and the gonyautoxin group (net charge, 1+), use of 1-heptanesulfonate as counterion, with or without acetonitrile in the mobile phase, resulted in resolution of decarbamoyl toxins from their carbamate analogues. C toxins having both M-sulfocarbamoyl and 11-hydroxysulfate moieties on the same molecule were completely resolved using the tetrabutylammonium ion. High sensitivity with detection limits ranging from 20 to 110 fmol were achieved as a result of reduced band broadening and optimized reaction conditions. For applications to biological matrixes, a cleanup procedure using a C18 solid-phase extraction cartridge was effective in preventing false peaks. When applied to low-toxicity shellfish, the liquid chromatographic method gave higher values than the standard mouse bioassay, because of underestimation by the bioassay.
Liquid Chromatographic Determination of Residual Isocyanate Monomers in Plastics Intended for Food Contact Use
Authors: Damant Andrew P , Jickells Sue M , Castle Laurence 
Published: February 2020

Abstract
A liquid chromatographic (LC) method was developed for the analysis of 10 isocyanates in polyurethane articles and laminates intended for food use. Residual isocyanates are extracted by dichloromethane with concurrent derivatization by 9-(methylaminomethyl)anthracene. The resultant derivatives are analyzed by reversed-phase LC with fluorescence detection. Separation of the isocyanates was studied and optimized. Quantitation uses 1-naphthyl isocyanate as internal standard and standard addition to the food package. Validation demonstrated the method to have good precision (± 2–5%) and recovery (83–95%) for samples spiked with isocyanates at 0.1 mg/kg. The limit of detection was 0.03 mg/kg. Analysis of 19 commercial polyurethane or laminate food packages demonstrated that the method was not prone to interferences. Residues of diphenylmethane-4,4′-diisocyanate were detected in 5 packages and ranged from 0.14 to 1.08 mg/kg.
Adulteration of Soluble Coffee with Coffee Husks and Parchments
Authors: Prodolliet Jacques , Bruelhart Melene , Blanc Maurice B , Leloup Valerie , Cherk Genevieve , Donnelly Catherine M , Viani Rinantonio 
Published: February 2020

Abstract
Commercial soluble coffee can be adulterated with coffee husks or parchments. Xylose is a good tracer for this type of mispractice. The analysis of total xylose in a wide selection of green beans and the assessment of its fate during processing allowed the derivation of a maximum total xylose limit of 0.40%, above which a soluble coffee should be considered as adulterated. Out of the 700 commercial soluble coffees analyzed, 81 exhibited a total xylose level above this limit. Of the samples with total xylose level lower than the limit, 99% displayed concentrations in free mannitol and total glucose below 0.30 and 2.10%, respectively.
Homogeneous Sample Preparation of Raw Shrimp Using Dry Ice
Authors: Bunch Elaine A , Altwein Diane M , Johnson Lloyd E , Farley Joyce R , Hammersmith Amy A 
Published: February 2020

Abstract
Sample homogeneity is critical to accurate and reproducible analysis of trace residues in foods. A method of uniform sample preparation using dry ice is described for shrimp. Other sample preparation techniques for raw shrimp produce nonhomogeneous samples. Sample homogeneity was determined through analysis of chloramphenicol added to intact tiger or white shrimp prior to sample preparation. Simulated chloramphenicol residue levels were 50, 15, 10, and 5 ppb. No significant differences were noted when analyses of shrimp inoculated with chlor-amphenicol prior to sample preparation with dry ice were compared with analyses of shrimp spiked after grinding with dry ice. Grinding shrimp with dry ice produced samples with homogeneous chloramphenicol residues. This technique should be applicable to other tissues and vegetable products.
LC-Receptorgram: A Method for Identification and Quantitation of β-Lactams in Milk by Liquid Chromatography with Microbial Receptor Assay
Authors: Zomer Eliezer , Quintana Julio , Saul Steven , Charm Stanley E 
Published: February 2020

Abstract
A rapid determinative method was developed for identification and quantitation of common β-lactam drugs (e.g., amoxicillin, ampicillin, cephapirin, penicillin G, ceftiofur, and cloxacillin) in milk. This method combines the advantages of liquid chromatography (LC) with the selectivity and sensitivity of a microbial receptor assay. This LC-receptorgram procedure identifies and quantitates β-lactams at 10 ppb or lower within 3 h. A simple purification scheme, using solid-phase extraction, gave recoveries ranging from 50% for amoxicillin to 80-90% for other β-lactams. Individual drugs were separated by LC using a reversed-phase C8 column and an isocratic buffer system containing methanol (35%) in phosphate buffer (50 mM, pH 6.0). The Charm II quantitative procedure was used to detect (5-lactams in the LC fractions. In a blind study of raw milk fortified with β-lactams, the coefficients of variance for quantitation of 6 β-lactams at the safe levels ranged from 4.1 to 13%. The confidence level for selectivity was greater than 99%, and for detection of positives at safe levels, it was 95% or greater. Analysis of 6 β-lactams in incurred samples showed that all 6 drugs are depleted to below 10 ppb in less than 48 h. Incurred samples with cephapirin and ceftiofur contained active metabolites, in addition to parent drug, that were detected by the LC-receptorgram. In market milk samples that screened positive in routine testing programs, penicillin G, cephapirin, and ceftiofur were identified by the LC-receptorgram as the most common contaminants. In several samples containing cephapirin or ceftiofur, an active metabolite was detected in addition to the parent drug. Only the parent drug was detected for other β-lactams.