bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analytical Methodology of Oxytetracycline in Feed
Authors: Billman D C 
Published: February 2020

Abstract
Preliminary evaluations have been conducted of the AOAC method for the assay of oxytetracycline in feed at the level of 10 g/ton. With careful techniques, nonmineral feeds containing 10 g/ton oxytetracycline can be assayed. Mineral feeds containing 10 g/ton oxytetracycline gave erratic results; further studies are planned with the use of compensating standard curves.
Collaborative Study of an Ultraviolet Spectrophotometric Method for Griseofulvin in Animal Feed
Authors: Kabasakalian Peter 
Published: February 2020

Abstract
Collaborative studies were made of an ultraviolet spectrophotometric method for determining griseofulvin in animal feed. Prior to measurement, the antibiotic is isolated from the feed by extraction with chloroform and separated from ultravioletabsorbing interferences in the extract by column chromatographic fractionation. The average recovery of griseofulvin by 9 collaborators was 103 ± 8.7% from fortified meal and 102 ± 9.7% from fortified pellets. The method is recommended for adoption as official, first action.
Malt Beverages and Brewing Materials
Authors: Stone Irwin 
Published: February 2020

Abstract
One new method, Total Haze of Beer After Chilling, is recommended for adoption as official, first action. Other new methods of the American Society of Brewing Chemists, which will be eventually submitted to the AOAC, are Diacetyl in Beer, Microbiological Controls, Aphids in Hops, and Physical Stability of Beer. The ASBC now has nine technical subcommittees investigating various analytical methods which may be of eventual interest to the AOAC.
Cryoscopy of Milk: Effect of Variations in the Method
Authors: Henningson R W 
Published: February 2020

Abstract
Bath level, sample temperature, rate of stirring, degree of supercooling, sample size, sample isolation, and refreezing of the sample were the variables in the thermistor cryoscopic method for the determination of the freezing point value of milk chosen for study. Freezing point values were determined for two samples of milk and two secondary salt standards utilizing eight combinations of the seven variables in two test patterns. The freezing point value of the salt standards ranged from –0.413 to –0.433°C and from –0.431 to –0.642°C. The freezing point values of the milk samples ranged from –0.502 to –0.544°C and from –0.518 to –0.550°C. Statistical analysis of the data showed that sample isolation was a poor procedure and that other variables produced changes in the freezing point value ranging from 0.001 to 0.011°C. It is recommended that specific directions be instituted for the thermistor cryoscopic method, 15.040–15.041, and that the method be subjected to a collaborative study.
Comparison of the FAO Schmid-Bondzynski-Ratzloff and Official AOAC Methods for Determining the Fat Content of Cheese
Authors: Weik R W , Horwitz William 
Published: February 2020

Abstract
The official AOAC method, 15.164, for determining the fat content of cheese was compared in six laboratories with the Schmid - Bondzynski - Ratzloff method, as adopted by the Food and Agriculture Organization of the United Nations. The results of analysis by the two methods are not significantly different; thus, the two methods can be used interchangeably.
Determination of Oven Moisture in Tobacco
Authors: Bortner C E , Ogg C L 
Published: February 2020

Abstract
A comparison of mechanical convection and gravity convection oven-drying of tobacco was made on 12 tobacco samples, six with high and six with low moisture content. Data show that better interlaboratory precision was obtained by drying in a mechanical convection oven. The term “apparent moisture” is vised becavise oven drying also causes loss of volatile organic material. The magnitude of this loss is shown to be from 0.25 to 1.5%, depending on the type and treatment of the tobacco. The forced draft oven method is recommended for adoption as official, first action.
Dessert Gel Strength Testing
Authors: Borker Emanuel , Stefanucci Arthur , Lewis Alfred A 
Published: February 2020

Abstract
The history of gelatin and gelatin dessert strength testing is reviewed. The current AOAC method for dessert gels using the Bloom Gelometer was found too variable for control of gelatin dessert production in a multi-plant operation. Variability can be reduced with a lower shot flow rate, rigid control of sample preparation, and frequent maintenance in gelometer alignment and adjustment. Detailed instructions for dessert gel strength testing are given.
A Rapid Method for the Quantitative Determination of Antihistamines and Some Related Compounds by Gas Chromatography
Authors: Celeste Anthony C , Polito Michael V 
Published: February 2020

Abstract
Laboratory-prepared and commercial samples of antihistamine mixtures are analyzed by gas chromatography with a Carbowax 20M-SE 30 phase on Anakrom ABS column. Recoveries for the simulated tablet preparations range from 96.9 to 102.5%. Recoveries from commercial preparations range from 90.7 to 113.2% of label declarations. Retention times for 12 antihistamines, dextromethorphan HBr, and phenylpropanolamine HC1 relative to diphenylpyraline HCI, the internal standard, are given.
Collaborative Studies of Methods for Determining Vanillin and Ethyl Vanillin in Flavoring Material
Authors: Fitelson J 
Published: February 2020

Abstract
Collaborative study was conducted on two ultraviolet absorption methods for vanillin and one paper chromatographic method for vanillin and ethyl vanillin. The official, first action screening method for vanillin was compared with another ultraviolet absorption method which determines p-hydroxybenzaldehyde. Results were more accurate by the ultraviolet absorption method than by the official method, when the estimation of p-hydroxybenzaldehyde was eliminated. The method is recommended for adoption as official, first action. Improvements have been incorporated into the paper chromatographic method to prevent tailing of spots, and the revised method is recommended for adoption as official, first action.
Extraneous Materials in Flour
Authors: Reed Garland L 
Published: February 2020

Abstract
Collaborative results are presented comparing method 36.02S(a) for extraneous materials in flour with method 36.029. Last fall method 36.029 was adopted as official, first action based on a collaborative study by the AACC. The present study was conducted to obtain additional data and to clarify the exact wording to be used in 36.029. The data, although limited, tend to show that the two methods are equal.
Improved Method for the Determination of Maggots in Canned Mushrooms
Authors: Brown Robert F , Aho Arthur C 
Published: February 2020

Abstract
Collaborative studies were conducted on a new sieving method, using both a nested combination of Nos. 20, 40, and 140 sieves and a crystal violet stain, for determining maggots and other arthropod filth in canned mushrooms. The method greatly improves the yield, accuracy, speed, and facility with which this determination can be accomplished. It is recommended for adoption as official, first action.
Rapid Flame Photometric Method for Sodium in Fruits
Authors: Boland Feederick E 
Published: February 2020

Abstract
The flame photometric method of Pro and Mathers for sodium in wines and distilled spirits has been adapted to the analysis of sample solutions of fruit and subjected to collaborative testing. A sample solution of fruit is aspirated directly into the flame photometer, which eliminates the need for ashing the sample and thus effects a saving of time. Six Food and Drug Administration District Laboratories, two State laboratories, and the Associate Referee participated in the collaborative study. The results indicate that the method is sufficiently accurate for the determination of sodium in fruit, and the method is recommended for adoption as official, first action.
Investigations of the Gas-Liquid Chromatography of Fruit Acids
Authors: Hautala Earl 
Published: February 2020

Abstract
Present analytical methods for the determination of fruit acids are long, since most require a separate determination for each individual acid. Gas-liquid chromatography offers a method capable of determining many acids by one procedure. Citric and l-malic acid esters were successfully prepared and chromatographed. Tartaric acid esterification and chromatography were attempted without satisfactory results. It is recommended that other stationary liquids and derivatives be studied.
Study of Extraction Procedures for Chlorinated Organic Pesticides in Fresh Eggs
Authors: Sawyer Allen D 
Published: February 2020

Abstract
The Johnson procedure was modified to provide a quicker and more satisfactory method for cleanup of fresh egg samples for chlorinated pesticide residue analysis. Acetonitrile extraction of the sample was followed by centrifugation of the extract and chromatography on a “layered” Florisil sodium sulfate column. The use of the “layered” column yielded 15% eluates suitable for direct analysis by microcoulometric gas chromatography. Unfortified egg samples were analyzed for DDD, DDE, DDT, heptachlor epoxide, and dieldrin by both this procedure and the Onley-Mills technique, and the results were compared.
Coliform and Total Bacterial Counts in Spices, Seasonings, and Condiments
Authors: Warmbrod Fred , Fry Linda 
Published: February 2020

Abstract
The regulatory program of the Tennessee Food and Drug Division has been extended to include microbiological contaminants in spices, seasonings, and condiments. Samples were examined for aerobic plate count, coliform count, and acid tolerant bacteria and mold counts. Some samples gave high coliform counts which may possibly indicate contamination. A regulatory program is more meaningful if microbacteriological examinations are made on food products.
Collaborative Study of Improved Sporicidal Test
Authors: Ortenzio L F 
Published: February 2020

Abstract
Collaborative data indicate that changes are needed in the present official sporicide test to avoid serious errors caused by carryover of the germicidal chemical into subculture tubes, slow germination time with exposed surviving spores, and failure of such spores to germinate in ordinary subculture and re-subculture tubes withovit a heat-shock treatment. Changes also appear desirable to reduce variations due to irregular drying of spores prior to exposure to sporicidal chemicals. A proposed revised text is recommended for adoption as official, first action.
Moisture in Dried Vegetables and Spices
Authors: Eader Bobby R 
Published: February 2020

Abstract
A collaborative study was conducted to compare the near-infrared spectrophotometric method and a Karl Fischer volumetric method with a vacuum oven method for the determination of moisture. Results by the near-infrared method were as accurate as and more rapid and specific than the vacuum oven method. Results by the Karl Fischer method were not as satisfactory; more study is needed to improve the precision of the method.
Rapid Procedure for Aflatoxin Analysis in Cottonseed Products
Authors: Stoloff Leonard , Graff Alan , Rich Harold 
Published: February 2020

Abstract
A new method for the determination of aflatoxins in cottonseed is presented and compared with two other procedures. This procedure yields good recovery for added aflatoxin, is relatively simple and rapid, and produces relatively clean extracts for TLC. A 75 g sample of ground cottonseed or cottonseed meal is extracted with aqueous acetone, centrifuged to remove solids, treated with lead acetate and acetic acid to precipitate interfering substances, and recentrifuged. An aliquot of the supernatant is mixed with powdered cellulose and packed into a chromatographic column for liquid-liquid partition chromatography. Hexane elutes the lipid materials; the aflatoxins are eluted with a hexane-chloroform mixture. After solvent evaporation, the aflatoxin-containing residue is dissolved in chloroform and chromatographed by TLC. Silica gel is the adsorbent; a benzeneethanol-water mixture is the developing solvent. The aflatoxin content is estimated by comparison with standard aflatoxins.
Determination of Molecular Weight
Authors: Ogg C L 
Published: February 2020

Abstract
An initial study, in which 23 collaborators participated, was conducted on the determination of molecular weight by the isothermal distillation (vapor pressure osmometry) method. Each used his own method and apparatus to analyze four samples in duplicate; the molecular weight ranged from 123 to 891. Results show that the chief problem is the choice of the correct solvent and reference standard and that the use of bare thermistors is questionable.
Determination of Chlorinated Pesticide Residues in Wheat by Electron Capture Gas Chromatography
Authors: Saha J G 
Published: February 2020

Abstract
Electron capture gas chromatography has been used to measure the efficiency of an extraction and cleanup procedure for chlorinated pesticide residues in wheat. Soxhlet extraction of ground wheat with acetonitrile, followed by partition into petroleum ether and cleanup on a magnesia-Celite column has been found adequate for the determination of heptachlor, aldrin, dieldrin, and endrin in concentrations as low as 5 ppb. Recoveries of aldrin, dieldrin, and endrin ranged from 98 to 104%, while those of heptachlor were 84–92%.
Gas Chromatography of Dinitro Herbicides
Authors: Boggs Hugh M 
Published: February 2020

Abstract
Dinitrophenolic pesticides tail badly when gas chromatography is attempted. Tailing can be eliminated by converting these pesticides to their methyl ethers with diazomethane and detecting these methylated compounds with electron capture gas chromatography, using either radium or tritium as the source. These compounds give symmetrical peaks on a 4′ × 4 mm i.d. column packed with 10% DC-200 on 90/100 mesh Anakrom ABS and operated at 150 or 200°.
Phenylmercuric Compounds: A Review of Analytical Methods and a Proposed Polarographic Assay
Authors: Hopes Ted M 
Published: February 2020

Abstract
A polarographic method, using pH 10 borate buffer and 0.1M KCl as the base solution, has been applied to phenylmercuric compounds. The second reduction wave given by phenylmercuric compounds is easy to measure. The limiting current is controlled by the diffusion and is directly proportional to concentration between 8 and 40 μg/ml. A sensitive test for free Hg++ will detect 3.7 μg/ml in the final test solution. The polarographic method is more specific, sensitive, and accurate than existing methods which are reviewed here. It is recommended that the method be applied to various pharmaceuticals.
Coulometric Determination of Kjeldahl Nitrogen
Authors: Christian Gary D , Jung Paul D 
Published: February 2020

Abstract
After digestion by official methods, samples were analyzed for nitrogen. The pH of an aliquot of the acid digest was adjusted to 8.6, and the ammonia was titrated with coulometrically-generated hypobromite. Distillation and preparation of standard solutions were eliminated, and the results agreed closely with those obtained by standard procedures.
A Flow Cell and Chart Ratchet for Repetitive Infrared Analysis
Authors: Ellis John H 
Published: February 2020

Abstract
A system for minimizing the recycling time between samples in an infrared quantitative analytical routine is described. This system utilizes flow-through attachments that allow changing samples without removing the cell from the spectrophotometer. A chart ratching device permits the instrument to scan automatically and repeatedly a portion of the spectrum and record each sample in sequence.
Determination of Nitrite and Nitrate in Meat Products
Authors: Landmann Wendell A 
Published: February 2020

Abstract
A study was initiated on a method for the simultaneous determination of nitrate and nitrite in meat products. Nitrate and nitrite are determined by difference before and after the reduction of nitrate with metallic cadmium. Nitrate is diazotized, coupled with sulfanilic acid and 1-naphthol, and measured. From 93 to 95% of nitrate and nitrite added to meat can be recovered, and nitrate and nitrite do not interfere with each other in the determination. Ruggedness tests were satisfactory, and the method should be studied collaboratively.
Oxidative Metabolism and Persistence of Parathion and Malathion on Field-Sprayed Lettuce
Authors: Coffin D E 
Published: February 2020

Abstract
Parathion and malathion, at a rate of 400 g active ingredient/acre, were applied individually to field plots of lettuce. Samples were taken at various intervals after spraying and analyzed by paper chromatography for residues of these compounds and their metabolites. Parathion residues decreased from 1.9 to 0.1 ppm in 4 days; detectable quantities were present up to 15 days. Small quantities of paraoxon and two unidentified metabolites of parathion were detected, at times, up to 2 days after application of parathion. Malathion residues decreased from 11.5 ppm at 4 hours to less than 0.1 ppm at 10 days. Malaoxon and three unidentified metabolites of malathion were detected, at times, up to 2 days after application of malathion.
Determination of Trace Levels of Copper in Soil Solutions With 1,5-Diphenylcarbazone
Authors: Geering H R , Hodgson J F 
Published: February 2020

Abstract
Soil solutions containing 3 to 14 ppb copper were analyzed colorimetrically with 1,5-diphenylcarbazone (DCO) as reagent. In this method, a 50 ml sample of soil solution is adjusted to about pH 1 with HCl (1 + 1) and copper is extracted from the solution with 0.025% dithizone/CCl4 solution. The dithizone extract is digested with 70% HClO4, redissolved in 5 ml 0.01M HCl, and diluted to 25 ml with water. A 20 ml aliquot of this solution is neutralized with 0.2M aqueous NH3 and buffered at pH 4.7 with 5 ml lM KH2PO4. Up to 3 μg copper is then determined by extracting the element from the aqueous solution into 5 ml benzene containing 0.0036% DCO. The color developed in the benzene layer follows Beer’s law at 550 mμ. As little as 0.1μg can be estimated with a precision of ± 10%.
Identification of Supplemental d- and dl-α-Tocopheryl Acetate in Premixes, Feed Concentrates, and Feeds
Authors: Tinkler F Howard , Passero Frank V , Ames Stanley R , Nelan Donald R 
Published: February 2020

Abstract
A procedure has been developed to distinguish between supplemental d- and dl-atocopheryl acetate in premixes, feed concentrates, and feeds. Tocopheryl acetate in a crude extract is partially purified by oxidative adsorption, de-esterified by saponification, and further purified by chromatography. Identification of the form of tocopheryl acetate is based on the change in optical rotation of the purified tocopherol measured before and after oxidation by potassium ferricyanide. In eight experiments the procedure was used on a poultry feed containing 4.5% fat and supplemented at levels of 10 and 20 IU vitamin E/lb with d- and dl-α-tocopheryl acetate. The form of supplemented tocopheryl acetate was readily identified in each case.
Determination of Lipids in Fish Meal
Authors: Lee C F , Ambrose M E , Smith P 
Published: February 2020

Abstract
Lipids were extracted from a series of twelve menhaden meals by six methods, and results were compared. The chloroformmethanol extraction method developed by Smith, et al., extracts approximately the same amount of lipids as the official AOAC method, 22.037. The Torry-TNO method with chloroform-methanol extraction, and acid and alkaline hydrolysis methods extract lesser amounts of lipids, but all methods extract more than the ethyl ether method, 22.032. The Smith-Ambrose-Knobl method, rather than AOAC method 22.037, is recommended for extraction of total lipids from fish meal because of its simplicity and efficiency.
Metabolism and Storage of DDT in Beef Cattle
Authors: McCully K A , Villeneuve D C , McKinley W P , Phillips W E J , Hidiroglou M 
Published: February 2020

Abstract
Beef steers were fed forage contaminated with technical DDT for 83 days. Fat samples were removed by omentectomy at various intervals after feeding of the contaminated forage had ceased. Residues of p,p′-DDE, DDD, and p,p′-DDT were found. DDD residues declined at the greatest rate, p,p′-DDT declined at an intermediate rate, while p,p′-DDE declined at the slowest rate.
In a second experiment technical DDT was administered orally, intraperitoneally, and intravenously to beef steers. Fat samples were removed by omentectomy 3 days after dosing. The steers that received technical DDT intraperitoneally and intravenously stored DDD and p,p′-DDT in the fat at a much lower ratio than the orally treated animals.
p,p′-DDT was administered by the oral, intraperitoneal, and intravenous routes in another experiment. Three and 8 days after dosing, the residues in the omental fat of the orally treated animals showed increased DDD to p,p′-DDT ratios when compared to these ratios for the other 2 groups which had declined from pre-treatment levels.
The data suggest that p,p′-DDT is dechlorinated to DDD in the rumen of the bovine.
Determination of Dichlobenil and Its Metabolite, 2,6-Dichlorobenzoic Acid, in Agricultural Crops, Fish, Soil, and Water
Authors: Meulemans Kenneth J , Upton Edwin T 
Published: February 2020

Abstract
A rapid and sensitive analytical method has been developed for the detection of residues of the selective herbicide, 2,6-dichlorobenzonitrile, and its possible metabolite, 2,6-dichlorobenzoic acid, in agricultural crops, fish, soil, and water. Plant extractives, which interfere with the electron capture gas chromatographic detection of these compounds, are removed by special column absorption chromatography. A limit of detectability of 0.05 ppm is obtained.
An Improved Method for the Analysis of DDT and Its Metabolites in Eggs
Authors: Beckman Herman , Bevenue Arthur , Carroll Kenneth , Erro Felix 
Published: February 2020

Abstract
A rapid method has been developed in which DDT residues are extracted from egg samples by blending with acetone and filtering, and then cleaned up on a Florisil column. An overall average recovery of 94.4% was obtained on samples fortified at levels of 0.05 to 1.0 ppm. The determinative step was electron capture gas chromatography; confirmation of the analysis could be obtained with microcoulometric gas, paper, or thin layer chromatography.
A Study of the Effectiveness of Some Extraction Procedures for Pesticide Residues in Vegetables
Authors: Burke Jerry A , Porter Mildred L 
Published: February 2020

Abstract
Nine blending-type extraction procedures were compared for effectiveness in removal of field-applied p,p’-TDE from kale. Extraction efficiencies were based on the amount removed by an exhaustive extraction. Acetonitrile, as used in the Mills, et al. rapid method for nonfatty foods, produced the highest result for this chlorinated pesticide, i.e., 99% of that removed by the exhaustive technique. Extraction efficiencies as low as 65% were obtained by some procedures. Higher results for field-applied diazinon and parathion were obtained by the Mills, et al. procedure than by the Watts and Storherr method.
Use of Thin Layer Chromatography for Detection of Contaminating Pesticides in Commercial Pesticide Formulations
Authors: Bontoyan Warren 
Published: February 2020

Abstract
A rapid and specific procedure has been devised for detecting chlorinated hydrocarbons, organophosphorus compounds, and other contaminating pesticides in commercial pesticide formulations. Samples were extracted with chloroform, spotted on thin layer plates, and compared to standards. Spots showing evidence of contamination are identified by gas chromatography and infrared techniques. Silver nitrate mixed with aluminum oxide and silica gel G are used as the immobile phases. Spraying is not necessary with the silver nitrate-aluminum oxide immobile phase.