bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improved 4-Aminoantipyrine Colorimetry for Detection of Residual Hydrogen Peroxide in Noodles, Fish Paste, Dried Fish, and Herring Roe
Authors: Ito Yoshio , Tonogai Yasuhide , Suzuki Hideyo , Ogawa Shunjiro , Yokoyama Tsuyoshi , Hashizume Takashi , Santo Hideyuki , Tanaka Kei-Ichi , Nishigaki Kikuyo , Iwaida Masahiro 
Published: February 2020

Abstract
Improved 4-aminoantipyrine (4-AA) colorimetry was developed for the detection of minute quantities of residual hydrogen peroxide in several kinds of food. Hydrogen peroxide in the sample was stabilized with potassium bromate and extracted with cold methanol. The methanol extract was diluted with phosphate buffer, protein was eliminated with zinc sulfate, and the extract was reacted with phenol, 4-AA, and peroxidase to the stable quinoneimine dye. The weak color solution was purified with Florisil column chromatography, concentrated, and determined by colorimetry. Recoveries of hydrogen peroxide from samples fortified at 0.5, 2, and 10 ppm ranged from 70.7 ± 8.9 to 98.5 ± 1.2%. Color development was linear with amount of H2O2 from 0.5 to 20 µg, corresponding to 0.05-2 ppm in samples.
Determination of Proof by Distillation: Low Results for Cocktails and Specialty Products
Authors: Mark Frances G , Vaughn Troy E 
Published: February 2020

Abstract
A variety of specialty products, as well as alcohol solutions containing individual ingredients of the products, were proofed according to the accepted distillation method for beverages containing &gt;600 mg extract/100 mL. Products and solutions containing non-dairy creamer, combinations of citric acid and sugar, or acetic acid gave distillates with specific gravities corresponding to proofs 0.2-0.7° lower than expected. Low results caused by carryover of acetic acid into the distillate can be prevented by making the sample alkaline before distillation. The mechanism of apparent reduced recovery of alcohol in the other cases is still under investigation.
Gas-Liquid Chromatographic Method for the Analysis of Microencapsulated Diazinon Insecticide: Collaborative Study
Authors: Karr James J ,   Collaborators:, Audino J B , Carlstrom A A , Chenery L T , Cox L M , DiPilla E J , Ellis N D , Gentry G M , Gerken D , Ginther B E , Hodgins E , Jung P D , Kahn B , King W , Launer J E , Law M W , Linhart B , MacEachern G , Minyard J P , Moya H , Renaux B , Rivera L , Schatz W E , Shah R D , Slatner J W , Smith W J , Topping A , Torrence A K , L Ullrich , Whitaker R L , Winstead G R , Wong D L 
Published: February 2020

Abstract
The determination of diazinon insecticide in Knox Out 2FM formulation was studied collaboratively by 18 laboratories. Knox Out 2FM is a flowable microencapsulated insecticide formulation containing 23 wt% active ingredient. Analytical samples are first treated by grinding in a tissue grinder and then extracted in situ with acetonitrile. This preparative step breaks the capsules and allows the active ingredient to dissolve in the solvent. Single determinations on each of 2 closely matched samples were made by flame ionization gas-liquid chromatography. The standard deviation by analysts was 0.18 wt% and the coefficient of variation was 0.76%. The combined laboratory and analyst variation gave a standard deviation of 0.59 wt% and a coefficient of variation of 2.49%. The method has been adopted official first action.
Atomic Absorption Spectroscopic Determination of Dimethylpolysiloxane in Juices and Beer
Authors: Kacprzak Jurgen L 
Published: February 2020

Abstract
A method is described for determining dimethylpolysiloxane (DMPS), an antifoaming agent, in juices and beer. The method involves adsorbing the beverage onto Florisil (an activated porous magnesium silicate), drying, and Soxhlet extraction with chloroform. The chloroform extract is evaporated to dryness and DMPS is determined in the residue after dissolution with methyl isobutyl ketone and aspiration into a nitrous oxide-acetylene flame of an atomic absorption spectrophotometer. The detection limit is about 0.2 ppm.
Direct Spectrophotometric Determination of Arprinocid in Premixes: Collaborative Study
Authors: Fink David W ,   Collaborators:, Baker K R , Bliss W J , Brignac P G , Brunsmann P , Cannon M J , Carr K E , Davis E J , Drewery G , Fink H C , Foster C L , Fox A , George G , Hanks A R , Lawrence A A , Leseney J L , Lowie D , Martin R P , Nichols F A , Portterfield D G , Riva M , Roozen W , Sikes P J , Smallidge R L , Stringham R W , Thorpe V A 
Published: February 2020

Abstract
A spectrophotometric analytical method for the determination of arprinocid [9-(2-chloro-6-fluorophenylmethyl)- 9H-purin-6-amine] in premixes has been evaluated in an interlaboratory collaborative study. The samples were prepared in pairs over the concentration range 10.1-16.2% arprinocid with 2 similar materials as carriers for the drug, and were distributed to 16 laboratories. Duplicate analyses were obtained within the overall paired sample design by a protocol which obviates data censoring and allows for statistical treatment according to both Youden and Steiner guidelines. Each collaborator was requested to run 1 determination on each of 16 differently numbered samples in groups of 8 on 2 different days. In this analytical procedure, the drug is extracted into CHC13 and transferred into 0.1N HC1 for measurement at 258 nm after isolation by liquid- liquid partitioning. The means of the analyses reported by the collaborators ranged from 96.9 to 101% of the true concentration of arprinocid and were not statistically significantly different (P &gt;0.1) from the true values. The coefficient of variation at the 12.2% formulation concentration level was 3.6%. The collaborative data were normally distributed (P ≮ 0.01) with a mean, median, and mode of 99.2, 99.2, and 100.0% recovery, respectively, and a standard deviation of 3.72%. In this distribution, 80% of the results were within the range 95.1-104.1% recovery. The systematic standard deviations of the 4 unit blocks (Sb) were each &lt;0.4% arprinocid and the analysis of variance demonstrated that laboratory bias is not statistically significant (P &gt;0.05). There is no statistically significant difference in either accuracy (P &gt;0.5) or precision (P &gt;0.05) between days, and the ruggedness test confirms that none of the 7 procedural variations which were selected for study has a significant effect on the analysis. This method has been adopted official first action.
Confirmatory Identification of Carbadox-Related Residues in Swine Liver by Gas-Liquid Chromatography/Mass Spectrometry with Selected Ion Monitoring
Authors: Lynch Martin J , Richard Bartolucci S 
Published: February 2020

Abstract
A confirmatory method has been developed to identify quinoxaline-2-carboxylic acid, the carbadox tissue residue, in swine liver, a target tissue, at the regulatory level of 30 μg/kg. Quinoxaline-2-carboxylic acid (QCA) is isolated from liver hydrolysates by solvent extraction and ion-exclusion chromatography, and a methyl ester derivative (CP-25,536 or QME) is identified by gas-liquid chromatography/ mass spectrometry with selected ion monitoring. The relative intensities of 3 ions: the base peak at m/z = 130, a second significant mass at m/z = 158, and the molecular ion (M+) at m/z = 188, are monitored simultaneously with a quadrupole mass spectrometer. Validation studies consisting of the analysis of liver fortified with QCA at the regulatory level and analysis of swine specimens containing physiologically incurred carbadox residues demonstrated that peak height ratios of ions in these tissue extracts corresponded to ion intensities of standards monitored at m/z = 188,158, and 130.
Electron Capture Gas-Liquid Chromatographic Determination of Morantel-Related Residues in Bovine Liver
Authors: Lynch Martin J , Bartolucci S Richard 
Published: February 2020

Abstract
A gas-liquid chromatographic assay has been developed to determine major residues of morantel in bovine liver, a target tissue, at levels of 0.2-0.8 ppm. The method is based on hydrolysis of the N-methyltetrahydropyrimidine portion of morantel and its metabolites to N-methyl-l,3-propanediamine, and conversion of the diamine to an N,N'-bis-(2-nitro-4-trifluoromethylphenyl) derivative. The addition of an internal standard, N-ethyl-l,3-propanediamine, to the tissue sample circumvents any potential problem that could arise from variable reaction yields, and eliminates the true recovery as a factor affecting the accuracy and precision of the procedure. The concentrations of the, derivatives are determined by pulsed electron capture gas-liquid chromatography over a linear dynamic range equivalent to 0.2-0.8 ppm morantel. The method has been evaluated at 0, 0.2,0.4, and 0.8 ppm levels in fortified bovine liver, and in a withdrawal sample containing physiologically incurred morantel residues. Mean values of 0.22 ± 0.015,0.40 ± 0.033, and 0.79 ± 0.045 ppm were found for fortified samples, 0.02 ppm for control liver, and 0.56 ± 0.050 ppm for the withdrawal sample.
Gas-Liquid Chromatographic Determination of Adipate Content of Acetylated Di-starch Adipate
Authors: Mitchell Gordon A , Vanderbist Michel J , Meert Florent F 
Published: February 2020

Abstract
A gas-liquid chromatographic method is described for rapid, quantitative determination of adipate content of acetylated di-starch adipate. The adipate group is very labile and, under mild alkaline conditions at ambient temperature, is easily hydrolyzed from the starch. Free adipic acid is formed by acidification of the solution with HC1, and then extracted with ethyl acetate. Ethyl acetate is removed under vacuum distillation, and a silyl derivative of the adipic acid is formed. Glutaric acid internal standard is introduced into the original starch sample before hydrolysis. An aliquot of the silylated solution is injected into a gas chromatograph fitted with a column having silicone oil as the active phase. A flame ionization detector is also incorporated. Results correlate well with the amount of adipylating reagent used. No adipic acid is detectable when a hydrolyzed, extracted sample of acetylated di-starch adipate is subjected to a second extraction. Recovery levels of adipic acid, from starches fortified with 100-500 ppm, are in the range of 97-102.5.%
Gas Chromatographic Determination of Sorbitol, Mannitol, and Xylitol in Chewing Gum and Sorbitol in Mints
Authors: Daniels Daniel H , Warner Charles R , Fazio Thomas 
Published: February 2020

Abstract
A method has been developed for determination of sorbitol, mannitol, and xylitol in chewing gum and sorbitol in mints. Chewing gum is partitioned between methylene chloride and water; the mint is simply dissolved in water. The aqueous extract is dried and the residue is derivatized with pyridine-acetic anhydride to form the corresponding peracetates. The derivatives are quantitated by gas chromatography using a 9 ft × 2 mm column packed with 10% Silar IOC on Chromosorb W/AW. Average recoveries of these sugar alcohols ranged from 96 to 102%.
Radioimmunoassay of Oxfendazole in Sheep Fat
Authors: Nerenberg Clinton , Tsina Irene , Matin Shaikh 
Published: February 2020

Abstract
Oxfendazole (methyl 5-(phenylsulfinyl)-2-benzimidazole- carbamate) is a broad spectrum anthelmintic agent designed for use in food-producing animals. A simple radioimmunoassay (RIA) for determination of oxfendazole in plasma was modified for determining oxfendazole in sheep fat. Fat tissue was enzymatically hydrolyzed to an oily residue with collagenase- hyaluronidase, and oxfendazole was then extracted into an acidified aqueous phase. An aliquot of this phase was used directly for RIA. Bound radioactivity was separated from free by using polyethylene glycol-bovine gamma globulin because oils and other components in the aqueous aliquot preclude the use of charcoal for the separation. The lower limit of sensitivity of the assay is 0.003 ppm. Accuracy experiments carried out in the range 0.01-0.5 ppm gave a regression line of y (ng/g) = 0.91x (ng/g) + 2.89, with r = 0.99. Fat tissue derived from sheep given an oral dose of 6.0 mg/kg was analyzed by this method and by a high pressure liquid chromatographic (HPLC) method. Values obtained by the 2 methods agreed well.
Effects of Particle Size and Method of Milling on Determination of Morphine in Papaver somniferum L. Straw
Authors: Engelke Beatriz Ferreira , Vincent Phillip G 
Published: February 2020

Abstract
Different particle sizes of blade- and ball-milled poppy straw were separated and analyzed for morphine by high pressure liquid chromatography. Morphine content varied up to 70% among the different size particles. This may account for discrepancies observed in percentages of morphine found among random aliquots. Homogenizing a carefully quartered sample of blade-milled straw by further pulverization in a percussion ball mill 2 min and taking a quartered aliquot for morphine analysis improved the reproducibility of results.
Susceptibility of Strawberries, Blackberries, and Cherries to Aspergillus Mold Growth and Aflatoxin Production
Authors: Llewellyn Gerald C , Eadie Thomas , Dashek William V 
Published: February 2020

Abstract
The susceptibility of blackberries, cherries, and strawberries to Aspergillus growth and aflatoxin production has been examined. Three aflatoxigenic isolates of Aspergillus, A. flavus ATCC 15548 and NRRL 3251 as well as A. parasiticus NRRL 2999, were cultured on homogenates of the fruits for 14 days at 28 ± 2°C. Percent mycelial growth and spore infestation were determined each day with a calibrated grid. At day 14 each culture was frozen at –5°C until aflatoxins were extracted with methylene chloride and water. Aflatoxins were separated by thin layer chromatography (TLC) with benzene-methanol-acetic acid (90 + 5 + 5). This extraction and solvent system provided satisfactory separations of the aflatoxins and was free of background interference on the TLC plates. Although all fruits served as substrates for both Aspergillus growth and aflatoxin production, cherries appeared to be a more favorable substrate than did blackberries, and the latter was more favorable than strawberries. Whereas A. flavus produced both B1 and G1 on all substrates, it yielded B2 and G2 only on cherries. Although A. parasiticus NRRL 2999 synthesized B1, B2, G1, and G2 on both blackberries and cherries, no aflatoxins were detected on strawberries. In contrast, A. flavus NRRL 3251 failed to produce detectable levels of aflatoxin on any substrate. All substrates supported both mycelial growth and subsequent sporulation with cherries &gt; blackberries &gt; strawberries.
Interaction Between Sample Preparation Techniques and Three Methods of Nitrite Determination
Authors: Fox Jay B , Doerr Robert C , Lakritz Leon 
Published: February 2020

Abstract
Meat samples containing nitrite and varying concentrations of ascorbate, cysteine, and sodium chloride were prepared for nitrite analysis. The methods used were the AOAC method of dilution and heating; the addition of mercuric chloride, charcoal, and Carrez reagents at 2 different pH values; and direct analysis of sample supernatants with no treatment (control). The effect of these initial conditions and preparation methods on measured nitrite was determined by using 3 different Griess reagent combinations and chemiluminescent and differential pulse polarographic techniques. Systematic variations were observed in samples treated with mercuric chloride, while the addition of Carrez reagents had little or no effect. Best results were obtained by the AOAC dilution/heating method under alkaline conditions, or by charcoal addition followed by chemiluminescent or colorimetric nitrite determination. Statistical analysis of the nitrite concentrations determined in the several samples showed that these 3 procedures were precise to about 5-6% CV, which was not significantly different from the CV value of 4% determined from replicate analyses.
Multicomponent Analysis of Meat Products by Infrared Spectrophotometry: Collaborative Study
Authors: Bjarnø Ole-Christian ,   Collaborators:, Arneth W , Noack W , Pfeiffer G 
Published: February 2020

Abstract
A new method for rapid multicomponent analysis of meat products based on infrared transmission was tested in a collaborative study with 4 laboratories. A series consisting of 31 samples of different meats, cooked sausage, liver sausage, and fermented sausage was distributed and analyzed at all laboratories for protein, fat, and water by the present method and by well established reference methods. There was no significant difference between the infrared method and reference methods at the 95% confidence level for determination of protein, fat, and water in meat products. There is a great
Tellurium as Catalyst in Semimicro Kjeldahl Method for Total Nitrogen Determination
Authors: Liao Christina F-H 
Published: February 2020

Abstract
A modified semimicro Kjeldahl procedure is described for total nitrogen determination in agricultural materials and refractory organic nitrogen compounds, in which tellurium, alone or in combination with copper, is used as a catalyst. Tellurium alone is adequate for complete recovery of nitrogen from nicotinic acid if the acid:salt ratio is carefully controlled to nearly 1. However, when a mixture of tellurium and copper is used, complete nitrogen recovery could be obtained at a higher acidrsalt ratio. Use of a mixture also reduces clearing time when compared with copper alone in the Kjeldahl digestion. For samples containing nitrate, a Devarda's alloy (Cu:Al:Zn = 10:9:1) is proposed as a reducing agent in the pretreatment procedure to convert nitrate to ammonium in 6N H2SO4, with subsequent digestion of the sample by using a mixture of K2S04-catalyst and concentrated H2SO4. The proposed method is applicable for total nitrogen determination including NO3-N in plant, soil, and fertilizer samples.
In Vitro Assay for Predicting Protein Efficiency Ratio as Measured by Rat Bioassay: Collaborative Study
Authors: Satterlee Lowell D , Kendrick James G , Marshall Henry F , Jewell Duane K , Ali Rida A , Heckman Mary M , Steinke H Fred , Larson Paul , Phillips R Dixon , Sarwar G , Slump P 
Published: February 2020

Abstract
Seven laboratories collaborated in testing the calculated protein efficiency ratio (C-PER and DC-PER). The collaborative study required each laboratory to analyze 6 foods and a control protein (ANRC casein) for in vitro apparent protein digestibility, amino acid composition, and PER via rat bioassay. The 6 foods or food ingredients tested were nonfat dry milk, cooked chicken muscle, protein-fortified dry breakfast cereal, textured soy protein, oat-based dry breakfast cereal, and durum wheat flour. Data obtained from the study were analyzed statistically for the intralaboratory variation for each method of analysis (i.e., amino acid analysis, PER, etc.). The ability of the C-PER to rapidly predict rat PER was also measured. The C-PER and DC-PER methods were adopted official first action.
Assessment of Quantitative Methods for Determination of Trichothecenes in Grains and Grain Products
Authors: Scott Peter M 
Published: February 2020

Abstract
Currently available methods for determination of trichothecenes are evaluated primarily for accuracy, precision, and limits of detection. A few of the more accurate and sensitive methods are discussed further with respect to convenience and number of trichothecenes determined. The best technique to date for quantitating trichothecenes is gas-liquid chromatography with electron capture or mass spectrometric detection, subject to available instrumentation.
Aflatoxicol and Aflatoxins B1 and M1 in the Tissues of Pigs Receiving Aflatoxin
Authors: Trucksess Mary W , Stoloff Leonard , Brumley William C , Wilson David M , Hale Otha M , Sangster Lowell T , Miller Doris M 
Published: February 2020

Abstract
Aflatoxicol (AFL) and aflatoxins B1 and M1 were found in tissues (kidney, liver, and muscle) of feeder pigs given an estimated LD50 oral dose of B1 (1.0 mg/kg body weight) provided as a rice culture of Aspergillus flavus and of market-weight pigs fed a naturally contaminated feed, containing aflatoxin Bi at a level of 400 ng/g from corn, for 14 days. The residues in all tissues decreased with time after treatment in both groups, with no detectable residues (approximate detection limits, ng/g, B1 0.03, M1 0.05, AFL 0.01) in pig tissues from the feeding experiment 24 h after withdrawal of aflatoxin-contaminated feed. B1 and M1, when found in the feeding experiment, were at about the same levels in all tissues except the kidney, in which M1 was the dominant aflatoxin. The level of AFL, when detected, was about 10% of the B1 level.
Liquid Chromatographic Determination of Aflatoxins in Artificially Contaminated Cocoa Beans
Authors: Hurst W Jeffrey , Lenovich Lawrence M , Martin Robert A 
Published: February 2020

Abstract
A high pressure liquid chromatographic method is described for the extraction and determination of aflatoxins in artificially contaminated cocoa beans. Aflatoxins were extracted by using a CB extraction, column cleanup, and chromatography on a reverse phase column with UV detection at 365 nm for aflatoxins B1 and G1 and fluorescence detection for aflatoxins B2 and G2 (365 nm excitation and 455 nm emission). Recoveries from artificially contaminated cocoa beans of various roast conditions ranged from 77.50 to 107.35%. CV values ranged from 4.87 for G1 to 7.66 for G2 (n = 8). The method can be used for cocoa beans ranging from no roast to a heavy roast (12 min at 400°F).
Colorimetric Determination of Ethambutol Hydrochloride
Authors: Shingbal Dattatray M , Naik Shailendra D 
Published: February 2020

Abstract
A precise colorimetric procedure is proposed for estimation of ethambutol hydrochloride, based on reaction of the drug with 2,4-dinitro-l-fluorobenzene under stipulated conditions. The yellow chromophore is quantitated spectrophotometrically at 376 ± 1 nm. The relationship between absorbance and drug concentration was linear within a range of 5-40 μg/mL. The method is suitable for the analytical control of ethambutol HCl and its formulations.
Trapping Low Levels of Methyl Bromide in Air or as Residues at Ambient and Lower Temperatures for Gas Chromatography
Authors: Dumas Theodore 
Published: February 2020

Abstract
Methyl bromide in air was analyzed by direct injection onto a trapping tube filled with Tenax GC and operated at 25 or 0°C. Methyl bromide amounts as low as 35 ng could be determined. Methyl bromide flushed from flasks and collected in cold traps before injection onto the trapping tube showed recoveries of 99% for 30 ng in a 60 L sample. This gas chromatographic method was also used to determine methyl bromide desorption from fumigated wheat; 0.3 ppb (10-9 g) was desorbed in 24 h from 1 g wheat aerated for 30 days.
Analytical Methods Used by Industry for Determining Lead in Processed Foods
Authors: Elkins Edgar R 
Published: February 2020

Abstract
Over the past 8 years, a number of food processors and can manufacturers have participated in repeated round-robin studies of lead methodology. During this period, 3 methods have been found to be comparable in a variety of foods: carbon rod atomic absorption, chelation-solvent extraction atomic absorption, and anodic stripping voltammetry. Each method is described and results are given from a number of round-robin studies. In general, the coefficient of variation at lead levels of 0.1-0.3 ppm is usually ≤20%.