bluuebunny/crossref_metadata_2025 huggingface dataset:
A New Flash Injector for Gas Chromatography of Organophosphorus Insecticides
Authors: Solomon J
Published: February 2020

A new "flash injector" is described which features the removal of solvent from organophosphorus insecticide solutions prior to gas chromatography, using the stacked flame ionization detector. A micro-thin film of sample is deposited on glass wool for instantaneous vaporization in the injection port by syringe-injecting an aliquot of sample into a Pyrex glass wool plug contained in a specially designed Pyrex glass tube that fits the injection port. After pre-vaporization of the solvent, flash injection is completed by inserting and sealing the tube in the injection port by a mechanical flash injector. The method prodvices good chromatographic peaks and resolution, eliminates solvent peaks and interferences, improves reproducibility, prolongs column life, eliminates the use of septums, and requires little or no cleanup of extracts. Errors due to blow-by in the syringe, caused by injection against high port pressures, are eliminated. Injections larger than 5 /il can be used to facilitate detection of organophosphorus residues in low concentrations without extinguishing the detector flames.
Gel Permeation Cleanup for Malathion in Wheat, Using a Non-Ionic, Cross-Linked Polystyrene Polymer
Authors: Aker Norman L , Schanderl Sigmund H , Leeling Norman C
Published: February 2020

A gel permeation method, using non-ionic, cross-linked polystyrene beads (Bio-Beads), has been utilized for the separation of malathion from wheat samples. Elution patterns, using malathion-fortified wheat extracts, established that interfering materials were eluted before malathion. Extracts containing up to 1 mg malathion were successfully cleaned up at flow rates of 34—40 ml/hr; preliminary results indicate that flow rates up to 125 ml/hr do not adversely affect separation. Recoveries of malathion from fortified wheat extracts ranged from 90 to 112% for 10 to 1000 jug quantities. Preliminary study indicated that the cleanup was adequate when mixtures of other insecticides were included in wheat extracts containing malathion. The use of a column of non-ionic, cross-linked polystyrene beads for extract cleanup is simple and economical, since no apparent change in column performance occurs after repeated use.
Zebra Fish Eggs and Larvae as Aflatoxin Bioassay Test Organisms
Authors: Abedi Z H , Mckinley W P
Published: February 2020

Aflatoxin B1 is acutely toxic to embryos and larvae of zebra fish, Brachydanio rerio (Hamilton-Buchanan). These organisms are sensitive to sub-microgram quantities of the toxin and can be used as bioassay test organisms. The larval response is easier to measure than embryonic response, and a standard dosage-mortality curve for the larvae can be developed in 33 hr. As an aflatoxin bioassay test organism, the larvae of zebra fish have several advantages over other test organisms, including ducklings, embryos, and tissue cultures. They require no special skill or equipment and can be obtained easily in the laboratory throughout the year.
Growth and Production of Aflatoxins by Aspergillus flavus on Red Pepper {Capsicum frutescens L)
Authors: Schindler A F , Eisenberg W V
Published: February 2020

Aspergillus flavus grew on a substrate of crushed and fresh red pepper (Capsicum frutescens) and produced anatoxins B1 and G1. In addition, there was a shift in the ratio of aflatoxins B1 to G1 as compared to the ratio of these aflatoxins when grown on a Wort agar substrate. The increase in the proportionate amount of aflatoxin G1 to aflatoxin B1 extracted from the crushed red pepper was statistically significant at the 0.1% level.
Determination of Heavy Metals in Wines by Atomic Absorption Spectrophotometry
Authors: Měranger J C , Somers E
Published: February 2020

The effect of alcohol and sugar concentration on the atomic absorption analysis of copper, zinc, nickel, chromium, lead, cadmium, and cobalt has been investigated. Sugar reduced the sensitivity of analysis but could be compensated for by using the method of additions. Interference from alcohol was avoided by introducing an evaporation stage, and the concentration of the above cations was determined by direct aspiration in 24 native and imported wines.
Use of Anatone and Microbiotine in Phenol Coefficient Method for Disinfectant Testing
Authors: Ortenzio L F
Published: February 2020

Preliminary studies were made of two peptones which are being considered to replace Armour's Peptone or USP Peptic Digest of Animal Tissue. Results indicate that collaborative study on Anatone is warranted.
The High Resolution NMR Spectra of Pesticides. I. Organophosphorus Pesticides
Authors: Keith Lawrence H , Garrison Arthur W , Alford Ann L
Published: February 2020

A description of the 100 MHz nuclear magnetic resonance spectra of forty organophosphorus pesticides is presented as an identification aid and reference source. Chemical shifts and coupling constants are presented in tabular form, along with a discussion and figures of the more complex or unusual spectra. Tables of trends in chemical shifts and coupling constants as related to structure are included. Homonuclear spin decoupling, integration, protonation with trifluoracetic acid, D20 exchange, temperature, solvent and dilution effects, and supplemental 60 MHz spectra all were employed in correlating the spectra with the structures of the corresponding molecules. Interesting phenomena observed include long-range phosphorus to hydrogen coupling through four and five bonds, chemical nonequivalence of methylene groups and methyl groups in (CH3CH20)2P and (CH30)2P moieties, differences in the spectra of the cis and trans isomers of two pesticides due to anisotropic effects of their carbonyl groups, and magnetic nonequivalence of geminal methylene protons adjacent to an asymmetric carbon atom
Sodium Methylate Treatment of Cleaned Up Plant Extracts in Confirmation of Some Pesticide Residues By Gas-Liquid and Thin Layer Chromatography
Authors: Mendoza C E , Wales P J , Mcleod H A , Mckinley W P
Published: February 2020

A rapid procedure that involves GLC-EC and TLC analyses of plant extracts 5 min after treatment with sodium methylate is described for the qualitative confirmation of some pesticide residues. Plant extracts are cleaned up by elution through a carboncellulose column before treatment. The compounds studied were aldrin, captan, carbophenothion, p,p'-DDD, de-hydrochlorinated p,p-DDD, p,p'-DDE, o,p -DDT, p,p -DDT, Diazinon, dieldrin, disulfoton, heptachlor, heptachlor epoxide, malathion, methoxychlor, de-hydrochlorinated methoxychlor, mevinphos, and parathion. The pesticides added to beet, lettuce, pineapple, potato, and wheat eluates were reliably confirmed by GLC-EC or TLC after sodium methylate treatment. The procedure could be used to confirm only some of the pesticides added to extracts of apples, carrots, cauliflower, grapes, and peas because of components in these samples that gave interfering peaks
Thin Layer Chromatography of Organophosphorus Insecticides with Several Adsorbents and Ternary Solvent Systems
Authors: Getz Melvix E , Wheeler Helen G
Published: February 2020

Forty-two organophosphorus insecticides were chromatographed on binder-free thin layer plates prepared from silica gel, aluminum oxide, and magnesium silicate. Five ternary solvent systems were used for the development and three selective chromogenic sprays for the identification of the migrated spots
Ultraviolet Spectra-Structure Correlations of Some Compounds of Pharmaceutical Interest: Review of General Principles
Authors: Furman William B
Published: February 2020

A brief survey of ultraviolet spectrastructure data is presented, oriented specifically toward the pharmaceutical chemist. Chromophores derived from benzene, phenol, pyridine, barbituric acid, xanthine, and phenothiazine are discussed in terms of wavelength of maximum absorbance and concentrations required for quantitative analysis
Determination of Small Bone Particles in Meat
Authors: Hill Robert M , Hites B D
Published: February 2020

Very small particles of bone can be separated from ground meats and meat products by the following procedure: The bulk of the meat is solubilized by digestion with papain and the bone is separated from the other nondigestible material according to its ability to settle in a carbon tetrachloride: acetone mixture. Turkey samples with widely varying bone content were analyzed, with good agreement between duplicate samples.
DDT-Type Compounds: Separation and Identification by a System Combining Thin Layer Chromatography, Gas Chromatography, and Infrared Spectroscopy
Authors: Abou-Donia M B , Menzel D B
Published: February 2020

Infrared spectroscopy, in combination with TLC and GLC, offers an effective technique for isolation, separation, and identification of DDT-type compounds. Rf values for DDT and 13 other compounds, most of which have been reported as DDT breakdown products, have been determined in 27 solvent systems, using TLC techniques. Three columns, in combination with the electron capture detector, have been experimentally studied to analyze the 13 DDT-like compounds. The positions and intensities of the infrared bands of the 14 compounds have been measured in KBr. The variations of these measurements have been discussed in relation to the structural changes of DDT-type compounds.
Determination of Cyclamates (Sodium and Calcium Salts) in Canned Fruits
Authors: Johnson D E , Nunn H B
Published: February 2020

A method for determining calcium or sodium cyclaniate in canned fruits and fruit products has been developed. The cyclamate salt in a homogenized portion of fruit is hydrolyzed to cyclohexylamine in the presence of hydrochloric acid at 125°C and 15 psi. The cyclohexylamine is extracted into chloroform and reacts with ethanolic p-quinone to produce 2-(cyclohexylamine)-l,4-benzoquinone, which is determined spectrophotometrically at 493 mµ. Sucrose and saccharin do not interfere. Eleven collaborators tested the method on canned pears, peaches, pineapple, and grapefruit. Each fruit was fortified at two different levels with sodium cyclamate. The average recovery of both levels of cyclamate salt in all four fruits was 98.7%. Each collaborator also tested the method on a can of commercially canned dietary peach pie filling. The results were good, and the method is recommended for adoption as official, first action.
Method for Evaluating the Potential Availability of Water-Insoluble Nitrogen Sources in Mixed Fertilizers
Authors: Katz Stanley E , Fassbender Carol A
Published: February 2020

A method was developed for the estimation of potential availability of waterinsoluble nitrogen sources in fertilizer based upon solution biodegradability procedures, i.e., water-insoluble nitrogen sources are degraded in the soil by microorganisms, making the nitrogen available to both plants and organisms. As the degradation of the nitrogen source proceeds in solution, the medium becomes turbid and the intensity of the turbidity reflects the degree of degradation. Eleven water-insoluble nitrogen sources and four commercial fertilizers were studied. Materials studied included representatives of plant, animal, marine, and synthetic origin. A parameter designated as the biodegradability index was proposed to better define water-insoluble nitrogen sources.
Determination of the Volume Weights, Water-Holding Capacity, and Air Capacity of Water-Saturated Peat Materials
Authors: Thorpe Virginia A
Published: February 2020

To evaluate the aeration, water penetration, and water retention properties of peat under field conditions of water saturation, the method for determining the volume weight, water-holding capacity, and air capacity of water-saturated peat materials has been proposed and studied collaboratively. Although statistical treatment of the collaborative results indicates a satisfactory degree of precision for the products under consideration, correlation of the results with data indicates that small changes in the “packing” technique of the method would be desirable. The proposed method, as amended, is recommended for adoption as official, first action.
Collaborative Study of Infrared Anatysis of Dicamba
Authors: Malina Marshall
Published: February 2020

A collaborative study was conducted on an infrared method for the analysis of dicamba and its liquid formulations. Each sample was dissolved directly and submitted to infrared analysis, and its absorbance was compared to a reference standard. Results from 13 collaborating laboratories showed excellent precision, with a coefficient of variation of 0.017. Six laboratories participated in the study on liquid formulations, and results also showed excellent precision, with a coefficient of variation of 0.021. This method is recommended for adoption as official, first action.
Collaborative Study of the Determination of Morphine in Paregoric
Authors: Smith Edward
Published: February 2020

A partition chromatographic method for the determination of morphine in paregoric and other opium preparations was subjected to collaborative study. The morphine is separated from associated opium alkaloids by successive elution through consecutive acidic and alkaline columns and is measured by UV absorbance. The isolated morphine was shown to have a high degree of purity. The method is rapid and the results of the collaborative study show good precision and accuracy. The method is recommended for adoption as official, first action.
Lysergic Acid Diethylamide: Review and Collaborative Study
Authors: Look James
Published: February 2020

A method for identification and determination of lysergic acid diethylamide (LSD) was studied collaboratively by 11 collaborators on three samples prepared by the Associate Referee. The presumptive test is a valuable tool for rapid preliminary examination. Racemization of the LSD adds further to its identification by paper chromatography. Assay recovery, based on Sandoz LSD-25 reference standard, was 98.0%. Recovery by the same assay, but based on Ergonovine Maleate USP Reference Standard, was 96.5%. The method is recommended for adoption as official, first action.
Analytical Profiles of Sorghum Cane and Sugar Cane Sirups
Authors: Johnson Arthur R , Sturdivant Arthur T
Published: February 2020

Authentic samples of sorghum sirup and cane sirup have heen ohtained and analyzed for total solids, reducing sugars, sucrose, ash, Winton lead number, and polarization at 87°C. These analytical data may he used as guides in establishing purity of the sorghum cane and sugar cane sirups. Because of the similarity and the overlapping ranges of values, the sirups cannot be readily distinguished in blends
Indoxyl Acetate Spray Reagent for Fluorogenic Detection of Cholinesterase Inhibitors in Environmental Samples
Authors: Schutzmann R L , Barthel W F
Published: February 2020

A cholinesterase inhibition method to detect ihionophosphates (P=S compounds) and their oxygen analogs (P=O) by twodimensional thin layer chromatography is described. Environmental samples are cleaned up on Florex columns and spotted on silica gel thin layer plates. Plates are developed in solvent mixtures of opposite polarity, then sprayed with an enzyme solution and indoxyl acetate. Submicrogram sensitivity is achieved by fluorogenic and chromogenic reaction. Some compounds give characteristic colored reaction products.
GLC Determination of Residues of Disulfoton, Oxydemetonmethyl, and Their Metabolites in Tobacco Plants
Authors: Bowman M C , Beroza Morton , Gentry C R
Published: February 2020

Residues of disulfoton and five of its metabolites on disulfoton-treated tobacco plants were analyzed as follows: Plant extracts were separated into three fractions by liquid chromatograpliy and an aliquot of each was analyzed by GLC, using a flame photometric phosphorus detector. The tobacco caused no background interference in the GLC analysis. Recoveries of five of the six compounds from plants fortified at the 1 ppm level were 88 to 100%; the sixth was unstable in tobacco and its oxidation products were detected. GLC response was linear up to the 250 ng level and the sensitivity was 0,01 to 0.04 ppm. The general procedure was also successfully applied to oxydemetonmethyl and its sulfone, which are chemically similar to two of the disulfoton metabolites.
Comparison of Four Extraction and Cleanup Procedures for Chlorinated Pesticide Residues in Eggs
Authors: Wessel John R
Published: February 2020

The extraction efficiencies, based on the amount of pesticide removed by an exhaustive extraction, of four procedures were compared for effectiveness in removal of chlorinated pesticide residues incurred in eggs from hens fed lindane, DDE, DDT, heptachlor epoxide, dieldrin, and endrin. Acetonitrile, as used in the Mills, Onley, and Gaither method for nonfatty foods, yielded results equivalent to the exhaustive extraction, the double acetonitrile extraction by blending, and the Sawyer rapid method for eggs. Two types of Florisil columns, a split layer and a single layer column, were compared for cleanup efficiency of egg extracts from the Sawyer and the Mills et al. methods. Results of these studies indicate that the Mills et al. rapid method is applicable for the analysis of chlorinated pesticide residues in eggs at a level of 0.01 ppm.
Extraction and Gas-Liquid Chromatographic Determination of Vernolate in Soil
Authors: Hermanson H P , Siewierski Marie , Helrich K
Published: February 2020

A gas-liquid chromatographic system using flame photometric detection was developed for the separation and measurement of residue quantities of vernolate and 1-propanethiol in soil. With a 3% Apiezon L on Chromosorb G column, the limit of detection was 0.003 μg for either compound.
Method for the Extraction of Light Filth from Seedless and Seeded Raisins
Authors: Gecan John S , Brickey Paris M
Published: February 2020

A method has been developed for the extraction of light filth from seeded and seedless raisins. Raisins are chloroform defatted, rehydrated in water, wet sieved, and extracted in a trap flask. Collaborative study resulted in reproducible recoveries and clean filter papers. This method is recommended for adoption as official first action.
TLC Determination of Uncombined 2-Naphthol-6-Sulfonic Acid (Sodium Salt) (Schaeffer Salt) in Color Additives
Authors: Moten Lueangier , Kottemann Christine
Published: February 2020

A thin layer chromatographic method is presented for determining uncombined sodium salt of 2-naphtliol-6-sulfonic acid (Schaeffer salt) in Ext. D&C Green No. 1. A direct fluorometric measurement may also be used to determine Schaeffer salt in Ext. D&C Green No. 1 and in FD&C Yellow No. 6. Uncombined Schaeffer salt in commercial samples of FD&C Yellow No. 6 varied from 0 to 0.5%; no samples of External D&C Green No. 1 were found to contain >0.1% of uncombined Schaeffer salt.
Subsidiary Colors in FD&C Blue No. 1
Authors: Stein Charles
Published: February 2020

The subsidiary colors in commercial FD&C Blue No. 1 have been identified by thin layer chromatography. They consist of dyes formed by the loss of one sulfonic acid group or of one sulfonated benzyl group from FD&C Blue No. 1.
Analysis of Cocoa Beans for Aflatoxins
Authors: Scott P M
Published: February 2020

The CB method for the analysis of peanut products for aflatoxins was modified to overcome the prohlem of an insoluble final residue when applied to cocoa: a 25% silver nitrate solution is used as the aqueous phase in the extraction procedure and the chloroform extract is reshaken with this reagent before column chromatography on silica gel. Good backgrounds arc obtained on TLC plates when the method is applied to powdered cocoa beans initially defatted with Ji-hexane. Recoveries of added aflatoxins are satisfactory (80-90%).
Quantitative Method for the Estimation of Aflatoxins in Peanuts and Peanut Products
Authors: Mayura K , Sreenivasamurthy V
Published: February 2020

A quantitative method for the estimation of four aflatoxins, based on chromatographic separations and selective destruction of B1 and G1 by nitric acid, has been developed. To enhance the specificity of the method, a sample blank is determined and is used to correct the values for nonspecific interfering substances.
Detection of Enzymatic Chillproofing Agents in Beer
Authors: Stone Irwin
Published: February 2020

A recently published ASBC method for the qualitative detection or semiquantitative determination of traces of proteolytic enzymes in beer is presented for adoption as official first action by the AOAC. Five other new methods of the ASBC are expected to have early publication. Eleven technical subcommittees are conducting studies.
Automated Determination of Zoalene in Feeds
Authors: Christopherson Howard L
Published: February 2020

Elimination of 5 steps (a quantitative wash, dilution to 100 nil, spiking an aliquot, evaporation to dryness, and dissolution in dimcthylformamide) in the official AOAC method for Zoalene in feeds and automation of the color reaction with cthylenediaminc using Technicon equipment has increased speed and precision several fold without significantly changing the chemistry of the AOAC method. A sampling rate of 80 analyses per hour with nearly steady state peak heights, good resolution hetween peaks, and low mixing noise was achieved hy using modified fittings and compressed gas for solution segmentation. A differential colorimeter provides automatic correction for feed blanks.
Recovery of 65 Organophosphorus Pesticides from Florisil with a New Solvent Elution System
Authors: Beckman Herman , Garber Dennis
Published: February 2020

The recoveries of 65 organophosphorus pesticides from Florisil have been measured. The data include reports of minimum detectable amounts of each compound on a comparable basis, the elution solvent syst em used, the elution pattern of the compounds, and a look into the structureactivity and structure-sensitivity relationships among the compounds. The compounds are divided into six groups based on the type of substituents associated with the phosphorus. A discussion of the significant points that were observed is given along with the tables of data.
Colorimetric Determination of Aklomide (2-Chloro-4-Nitrobenzamide) in Poultry Feed
Authors: George Glenn M , Daftsios A C , Morrison Joseph L
Published: February 2020

The coccidiostat aklomide is extracted from feed with methanol and assayed colorimetrically by reduction of the nitro group to anamine with titanium trichloride and subsequent color development with t he Bratton-Marshall reaction. Thirteen laboratories studied the method collaboratively on two levels of medicated feed. Overall average recovery was 106.5% of the oretical for the low level and 104.5% of the oretical for the high level. The method is recommended for adoption as official first action
Tar and Nicotine in Cigarette Smoke
Authors: Pillsbury H C , Bright C C , O"Connor K J , Irish F W
Published: February 2020

Cigarettes were conditioned 24 hr at 75°F and 60% relative humidity prior to being selected and smoked in a random order. Cigarettes were smoked in a Cambridge filter holder on an automatic smoking machine to a pre-determined butt length. TPM wet collection was on a CM113A filter disk and was determined as the net weight gain in the Cambridge filter holder after smoking. The filter pads were extracted with dioxane-isopropanol solution and were analyzed for moisture by gas chromatography. The pads and solvent extracts were steam distilled and the distillate was analyzed spectrophotometrically for nicotine. TPM dry was calculated as TPM wet minus nicotine and water. The coefficient of variation in this method is less than 5% with a 95% confidence level.
Comparison of White Gasoline and n-Heptane for Recovery of Insect Fragments and Rodent Hairs from Food Products
Authors: Thrasher Joel J , Brickey Paris M
Published: February 2020

A study is described in which re-heptane is compared with gasoline as flotation oils from water and alcohol lower phases. n-heptane, containing less than 4% toluene, gave higher and more reproducible insect fragment and rodent hair recoveries than gasoline when used with an alcohol lower phase. Recoveries were comparable between n-heptane and gasoline when used with a water lower phase. In both cases filter papers were cleaner or contained equal amounts of plant debris as obtained with gasoline. It is recommended that re-heptane replace gasoline for use as the flotation oil in alcohol and water extractions, and that "n-heptane# replace the word "gasoline# in method 36.002(o).
Collaborative Study on the Quantitative Gas Chromatographic Determination of Lactic and Succinic Acids in Eggs
Authors: Staruszkiewicz Walter F
Published: February 2020

A GLC method developed for the quantitative determination of lactic and succinic acids was studied collaboratively by six laboratories. Extracts of 25-50 g egg, with 1-86 mg lactic and 0.4–50 m g succinic acids added, were prepared in our laboratory by present AOAC procedures. The collaborators analyzed the extracts by formation of the propyl esters through reaction with BF3-ra-propyl alcohol reagent. Gas chromatography was performed with acetophenone as internal standard on a diethylene glycol succinate column using a flame ionization detector. The resulting peak heights were used to quantitate the acids. For samples containing less than 10 mg lactic acid and less than 14 mg succinic acid, 28 of 30 determinations were within 1.0 mg of the known a mounts . The standard deviations for these samples were all less than 0.6 mg. The overall per cent recovery for all samples averaged 105.2% for lactic acid and 101.9% for succinic acid. The method seems to give reliable results and to be as practicable as the AOAC methods.
Collaborative Study of the Determination of Boron as Boric Acid in Caviar
Authors: Brunstad Joan W
Published: February 2020

Caviar containing boric acid at the 0.5% level was subjected to an interlaboratory study. Boron is quantitatively determined as the boron-curcumin color complex in the 0-5 jug range. Qualitative determination of boron in the 1–3 ng range is achieved using TLC. A prepared sample of caviar and an actual import sample were analyzed simultaneously. The methods are recommended for adoption as official first action.
Bratton-Marshall Reagent for the Detection of Substituted Urea Herbicides and Metabolites on TLC Plates
Authors: Onley John H , Yip George
Published: February 2020

The Bratton-Marshall reagent is used in a thin layer chromatographic analysis for eight substituted urea herbicides (chloroxuron, diuron, fenuron, fluometuron, linuron, metobromuron, monuron, and neburon) and some major metabolites in crop samples. Samples are cleaned up by a previously described procedure, spotted on alumina plates, and developed. All compounds are made visible by hydrolyzing, diazotizing, and spraying with N-(1-naphthyl) ethylenediamine. Immediately, characteristic pink-to-purple spots appear for all compounds against a light background. The least amount of compound detected, as a standard, is 0.1 μg. Recoveries on apples, asparagus, corn, grapes, pineapples, and green beans at fortification levels of 0.025 to 2.0 ppm arc estimated to be greater than 70%.
Alkaline Pre-Column for Use in Gas Chromatographic Pesticide Residue Analysis
Authors: Miller George A , Wells Clyde E
Published: February 2020

An alkaline pre-column is described for use with gas-liquid chromatographic analysis of pesticide residues. The alkaline layer is contained in one side of a column with dual injection ports so that it can be used when additional information is needed for better chromatogram interpretation. The alkaline pre-column destroys some pesticides, changes the retention times of others, and leaves some unaltered. Many troublesome crop peaks are eliminated, thereby permitting quantitation and/or identification of many pesticide residues. Physical column characteristics are described and relative retention time data are reported for 32 commonly found pesticides.
Separation of Fixed Organic Acids in Table Sirups
Authors: Johnson Arthur R , Fernandez-Flores Enrique
Published: February 2020

A number of organic non-nitrogenous acids have been separated from table sirups and identified by gradient elution chromatography and by programmed temperature GLC analysis of the trisilyl derivatives of the acids.
Extraction of Plant Sterols from Adulterated Butter Oil Using a Digitonin-Impregnated Celite Column
Authors: LaCroix Denis E
Published: February 2020

The phytosterol, β-sitosterol, can be used as an index of adulteration of butter oil with vegetable oils. A rapid, semimicro method for the analysis of plant sterols in butter oil adulterated with vegetable oils is described. The sterols are removed from the adulterated butter oil by passing the sample through a digitonin-impregnated Celite 545 column, eluted with dimethyl sulfoxide, and analyzed for β-sitosterol by GLC, using a 3% JXR column. The amount of β-sitosterol extracted from samples of butter oils adulterated with 5% levels of cottonseed, soybean, peanut, and safllower oils compare favorably with the β-sitosterol values obtained from equivalent amounts of each of the respective vegetable oils which were tested. As little as 3 mg β-sitosterol/100 g butter oil can be readily detected by this method.
Proposed Revision for Preparation of Meat Samples for Total Phosphorus Determination
Authors: Okamoto M , Shafer J W , Ettinger C L
Published: February 2020

Six ham samples were analyzed in duplicate by nine laboratories for total phosphorus. The samples were dried and ashed in a muffle furnace at 550°C according to method 2.017(c) and the proposed method. The gravimetric quinoline molybdate method, 2.025(b), was used to determine total phosphorus in both preparations. No statistically significant difference (p = 0.05) was found among the phosphorus values obtained by the above treatments.
Modification of Method for Aflatoxins in Milk
Authors: Masri M S , Page J R , Garcia V C
Published: February 2020

Our previously described method for aflatoxin M in milk was modified to simplify and shorten the method. The use of basic copper carbonate as a cleanup aid with chloroform extracts is recommended for aflatoxin B1 but not for aflatoxin M analysis.
Paper Chromatographic Detection of Major Organic Acids in Fruit Juices
Authors: Fitelson J
Published: February 2020

The official AOAC paper chromatographic method for organic acids in vanilla extract has been modified slightly for fruit juices. Fruit juices are characterized by simple major organic acid patterns, so that addition of a foreign acid or cheaper fruit juices can frequently be detected by significant changes in the major organic acid pattern. A standard acid solution, developed simultaneously, provides a rough measure of the acid spot intensities. Eight collaborators participated in the examination of the two samples submitted. Two authentic juices were also provided for comparison purposes. All collaborators correctly found the unknown cherry juice to be adulterated with citric acid. Seven of the eight collaborators also reported correctly that the unknown blackberry juice was adulterated, although the acid pattern of this juice is more complicated and the addition of citric acid is more difficult to detect. The method is recommended for adoption as official first action.
Improvements in the Official First Action Method for Extraction and Assay of Nystatin in Animal Feeds
Authors: Platt T B , Levin J D , Massey Margaret A
Published: February 2020

An investigation was made of the steps used to prepare samples for assay of nystatin in feeds by the official first action method. Sample preparation can be simplified by eliminating the hexane wash and vacuum distillation to remove methanol. The need for a feed blank extract to prepare the standard curve was confirmed, but a simpler procedure was devised to produce the blank extract. It is recommended that the method be tested collaboratively.
Semimicro Method for Determining Total Lipids in Fish Meal
Authors: Ambrose Mary E , Roche Barbara J , Knobl George M
Published: February 2020

A simple and rapid method lias been developed for determining lipids in fish meal. Lipids are extracted with chloroform and methanol; the entire procedure requires no more than 10 min. An aliquot of the chloroform layer is dried at 50°C under nitrogen and then equilibrated 90 min in a desiccator. Twelve samples can be completed in a single day, compared to the three days required to complete an analysis by AOAC method 22.037. Results of the extraction method average 99.0% of those obtained by method 22.037.
Collaborative Study of a Rapid Electrophoretic Method for Fish Species Identification
Authors: Learson Robert J
Published: February 2020

A rapid electrophoretic method for fish species identification, using cellulose acetate as the supporting medium, was collaboratively studied to determine whether photographs of standard protein patterns from authentic species could he used to identify unknown samples. Twelve collaborators were sent six unknown samples of fish in duplicate to identify from a set of photographs representing standard patterns from nine species of fish. Results obtained from the 10 reporting collaborators indicated that correct identification from photographic standards was extremely difficult. Although the analysts were able to match the duplicates with an accuracy of 90%, only 39% of the unknowns were correctly identified. It is recommended that the method be collaboratively studied using authentic fish samples for standards instead of photographic standards.
GLC Flavor Profile of Maple Sirup
Authors: Underwood J C , Filipic V J , Bell R A
Published: February 2020

Studies during the past several years on the flavorants of maple sirup have led to the development of a GLC procedure that produces a chromatogram representing a flavor profile of maple sirup. The analysis of numerous maple sirups from different regions of the maple belt shows that the geographic location of maple trees does not qualitatively affect the major flavorants of maple sirup.
Rapid Screening Procedure for Determination of Benzoic Acid and Sorbic Acid in Fruit Beverages
Authors: Gantenbein W M , Karasz A B
Published: February 2020

A rapid and accurate method, requiring one extraction and UV analysis, has been developed for simultaneous detection of benzoic and sorbic acids in fruit beverages. Quantitative measurements of benzoic and sorbic acids are based on the strong absorbances at 225 and 250 mμ, respectively. Recoveries of benzoic and sorbic acids from orange juice and apple juice at levels normally present were adequate.
Differentiation of Certain Types of Cassias and Cinnamons by Measurement of Mucilaginous Character
Authors: Stahl William H , Skarzynski Jean N , Voelker William A
Published: February 2020

A simple method has been refined to differentiate Korintji and Batavia cassias from cassias of different geographical origin and also from true cinnamons. A certain particle-size fraction of the spice is slurried in an isopropyl alcohol-water mixture, heated to 80°C, transferred to a 100 ml graduated cylinder, shaken, and allowed to settle over a 2 hr period. The height of the column of sediment is measured. Korintji and Batavia give average column heights of 85.0 ml with a standard deviation of 6.7, and Seychelle cinnamon and Saigon cassia give an average height of 25.3 ml with a standard deviation of 4.1.
Estimation of Monosodium Glutamate in Food Products
Authors: Fernandez-Flores E , Johnson Arthur R , Blomquist Victor H
Published: February 2020

A procedure for estimating monosodium glutamate is described in which all food substances are extracted with water if an insignificant amount of starch is present, or with acetone-water solution when starch is present. An aliquot of the concentrated extract is chromatographed on a column of Dowex 50W—X8 (H+ form). The glutamic acid is retained on the column and eluted with 1N HCl. The glutamic acid content of the eluate is readily determined by the Sorensen formaldehyde titration procedure for amino acids, and the monosodium glutamate can be calculated.
Effect of Comminution on Mold Counts of Tomato Products
Authors: Eisenberg William V , Parran Hamilton M , Schulze Arnold E , Douglas Ruth G
Published: February 2020

New data are presented on the effect of particle-size reduction of tomato tissue by special milling equipment, such as the Urschel Comitrol, on mold and rot fragment counts of tomato products. Prior mold count data as related to other types of equipment used for control of particle size are discussed. The mold count-rot fragment count ratio characterizes the product with respect to processing and permits the determination of comparable counts on products produced by different processes.
Collaborative Study of the GLC Determination of Glycerine and Propylene Glycol in Tobacco
Authors: Giles J A , Cundiff R H
Published: February 2020

A method for the methanolic extraction of glycerine and propylene glycol from tobacco and their determination by gas chromatography was collaboratively studied by 11 laboratories. Results show unacceptably high systematic error standard deviations. Additional study and refinement of the procedure will be required before it is suitable as a standard method.
Collaborative Study of the Sweep Co-Distillation Cleanup for Chlorinated Pesticide Residues in Edible Fats and Oils
Authors: Malone Bernadette , Burke Jerry A
Published: February 2020

A collaborative study was made of the sweep co-distillation cleanup method for multiple residues of chlorinated pesticides in edible fats and oils with determination by electron capture GLC using a column of 15% QF-1/10% DC-200 on 80–100 Gas Chrom Q. Heptachlor epoxide, p,p’-DDE, dieldrin, p,p’-TDE, and p,p’-DDT were added at two levels to butterfat and soybean oil. Mean recoveries of pesticides ranged from 86.0 to 102.1% in soybean oil and 86.4 to 98.8% in butter.
TLC Separation and Spectrophotometric Determination of 2-Aminoanthraquinone in D&C Blue No. 9
Authors: Bell Sandra J
Published: February 2020

Batches of 3,3’-dichloroindanthrene meeting the specifications set forth in the Color Additive Regulations are certifiable as D&C Blue No. 9. One of the specifications requires that D&C Blue No. 9 contain no more than 0.2% 2-aminoanthraquinone. In the method described, 2-aminoanthraquinone is extracted from D&C Blue No. 9 with dimethylsulfoxide, together with several other impurities. This solution is spotted onto a thin layer plate and developed with diethyl ether. After removal from t he plate, the 2-aminoanthraquinone is extracted into acetic acid and the amount is determined spectrophotometrically. Recoveries of 0.1, 0.2, and 0.5% of added intermediate ranged from 86 to 96%.
Determination of Phosphorus in Fruits and Fruit Products by a Spectrophotometry Molybdovanadate Method and by the Official Gravimetric Quinoline Molybdate Fertilizer Method
Authors: Estrin Ben , Brammell Wallace S
Published: February 2020

A newly developed spectrophotometric molybdovanadate method and the official gravimetric quinoline molybdate fertilizer method, 2.025(b), slightly modified, were used to determine phosphorus in fruits and fruit products. In the former method, the use of hazardous perchloric acid is avoided by dry-ashing the sample as in method 20.017 and by using nitric acid rather than perchloric acid in the molybdovanadate reagent. In the quinoline molybdate method, the sample is dry-ashed in the same way. In both proposed methods, the official ash solution is used for the phosphorus determination as in the official volumetric method, 20.031–20.032. Ash weight can be obtained before preparing this solution; in the official colorimetric method, however, a second aliquot must be dry-ashed for the ash weight. The two proposed methods gave results in good agreement with those obtained by the official volumetric method. These methods are simpler and faster than the two present official methods.
The High Resolution NMR Spectra of Pesticides. II. The DDT-Type Compounds
Authors: Keith L H , Alford A L , Garrison A W
Published: February 2020

The high resolution nuclear magnetic resonance spectra of the DDT class of pesticides and related compounds are discussed, including a study of the resonances of the aromatic protons as they are affected by various substiluents. The CCl3 moiety on the α-carbon strongly deshields the ortho protons on the aromatic rings, and this deshielding effect is greatly enhanced by substitution of a chlorine ortho rather than para on the aromatic ring. These deshielding effects are explained by a consideration of the electronegativity of the substituents and the stereochemistry of the molecule. The chemical shifts and coupling constants are tabulated.
Dry Ashing Method for the Determination of Total Arsenic in Poultry Tissues
Authors: Morrison Joseph L , George Glenn M
Published: February 2020

A method is described for the determination of arsenic in poultry tissue, which is sensitive to levels of less than 0.1 ppm. Tissue samples are dry-ashed in the presence of magnesium oxide and magnesium nitrate and the arsenic is determined colorimetrically with silver diethyldithiocarbamate. Arsenic content in the tissue is determined from standard curves prepared for each tissue; this technique corrects for losses during the ashing step.
Sensitive Identity Test for Chlortetracycline in Fish
Authors: Blakely Jocelyn , Kramer Julian , Selzer George B
Published: February 2020

Residues of chlortetracycline in fish at a level of 0.10 ppm may be identified by the method described. The antibiotic is extracted into butanol, chromatographed on a paper moistened with pH 4.6 Macllvaine’s buffer and developed with nitromethane-chloroform-pyridine (20 + 10 + 3), and detected on plates inoculated with Bacillus cereus var. mycoides in a pH 6.6 agar base. The procedure will also identify residues of the other tetracyclines in fish.
Enhanced Recovery of Salmonella montevideo from Onion Powder by the Addition of Potassium Sulfite to Lactose Broth
Authors: Hall Joanne R
Published: February 2020

The use of K2SO3 in lactose broth pre-enrichment media was studied as a means of enhancing the recovery of salmonellae from onion powder. Salmonella montevideo was inoculated at several dilutions into lactose broth containing varying amounts of onion powder, with and without the addition of 0.5 g K2SO3. Recovery was improved when K2SO3 was added. In another series of determinations, 0.5 g K2SO3 was added to lactose broth and the S. montevideo initial inocula were varied from approximately 5 to 5 × 107 organisms; the amount of onion powder was also varied (0.1 to 12 g). Results show that when 3 to 10 g onion powder was used, 0.5 g K2SO3 in lactose broth enhanced the recovery of S. montevideo.
Report of the Joint AOAC-AOCS Aflatoxin Committee
Authors: Fischbach Henry
Published: February 2020

The Joint AOAC-AOCS Aflatoxin Committee, first proposed in 1964 and an active committee in 1965, coordinates methods development in the two societies. The history and accomplishments of this committee are outlined and the areas of interest of the AOAC and the AOCS are defined. Since the committee’s inception the following actions have been taken: AOAC has adopted two methods for peanuts and peanut products and a chemical derivative confirmation test as official final action and a method for cottonseed as official first action; the AOCS has adopted one of the above methods for peanuts and peanut products as a Tentative Method. The AOAC Associate Referee topics for anatoxins are listed and the current status of research under these topics is described.
Quantitation of Food Adulterants by Multiple Radial Immunodiffusion. I. Cross-Reacting Antigen Mixtures
Authors: Lietze Arthur
Published: February 2020

Two cross-reacting antigens were isolated from wheat flour. These antigens were recombined in various proportions and various dilutions and were analyzed by radial immunodiffusion, using an antibody against wheat flour. The results demonstrate that multiple radial immunodiffusion is a valid analytical technique. If antigens cross-react they must be present in a known ratio. This ratio can be estimated from the experimental data.
Computer-Generated Table for the Selection of Chromatographic Column Systems to Separate Organic Bases
Authors: Farrell Terryl J , Pecsok Robert L
Published: February 2020

A computer has been used to generate a set of tables describing the data of Doyle and Levine for selecting optimum conditions to separate organic bases. The tables show all compounds on the same sheet of paper, thus avoiding the use of a separate graph or overlay for each compound. The computer program can generate additional entries for other bases as the data become available.
Spectrophotometric Determination of Caffeine in Leaf Tea
Authors: Newton John M
Published: February 2020

A UV spectrophotometric method for the determination of caffeine in leaf tea has been studied collaboratively by 13 laboratories on four different types of leaf tea. The chromatographic cleanup procedures are those of the official AOAC chromatographic methods for caffeine in APC and in coffee. The coefficient of variation for all samples studied collaboratively ranged from 3.74 to 5.78%. The method is recommended for adoption as official first action.
Investigation of Volatile Reducing Substances as an Indicator of Decomposition for Raw and Processed Foods
Authors: Moorhouse Barbara R , Salwin Harold
Published: February 2020

Volatile reducing substances (VRS) in foods were determined by an empirical procedure in which volatiles are stripped by aeration from an aqueous extract of a sample, passed through alkaline potassium permanganate, and measured by the extent of permanganate reduction. Experimental parameters were investigated as a step toward developing a standardized procedure. Dilute methanol was investigated as a reference solution, the equipment described in published procedures was simplified, and some operating conditions were controlled. The amount of permanganate reduction increased with length of aeration, but variations in aeration rate from 1360 to 1790 ml/min were not critical. The method was applied to ground beef, shrimp, and peaches. The raw food materials were stored at ice or refrigeration temperatures until they reached a decomposed state. Samples withdrawn at intervals during storage were processed and preserved by freezing or by freeze-drying. The content of VRS in raw samples increased as the foods decomposed. The VRS were partly lost during cooking and completely lost during freeze-drying. Therefore, the VRS content appears to have promise as an index of decomposition for a variety of raw foods and possibly for some cooked foods, but not for foods that have been freeze-dried.
Chromatographic Separation and Fluorometric Analysis of Cocci diostat Nequinate (Statyl®) in Feed Mixtures
Authors: Krol George J , Nash Norris G
Published: February 2020

Nequinate is separated from the constituents of feed extracts by partition column chromatography utilizing Sephadex LH-20. The isolated fraction containing the drug is analyzed by a fluorometric procedure. The sensitivity of the fluorometric determination is enhanced 50-fold by the addition of methanesulfonic acid. Structurally related coccidiostats or other drugs currently used in feed mixtures do not interfere.
Fatty Acid Composition of Crude and Refined Cottonseed Oils
Authors: Iverson John L
Published: February 2020

The fatty acid composition of 20 cottonseed oils was determined by isothermal GLC analysis of the total esters. A urea fractionation procedure, combined with modified programmed temperature GLC, was used to detect esters present in trace amounts (0.001–0.1%) in four refined and three crude oils. The odd a n d even chain length saturated acids from C8 to C26 were present. Mono-unsaturated acids from C15 to C20 were also detected. The crude and refined oils did not differ markedly in their fatty acid composition. The presence of malvalic and sterculic acids and the possible presence of shorter and longer chain length cyclopropenoid acids with their interfering GLC peaks make it impossible to detect and quantitatively estimate the branched and multiple branched acids.