bluuebunny/crossref_metadata_2025_split huggingface dataset:
Collaborative Study of a Method for the Determination of Weight Per Unit Volume of Packaged Ice Cream
Authors: Habeger Larry E 
Published: February 2020

Abstract
A new method and the official AOAC method (15.181) for the determination of weight per unit volume of ice cream were compared in a collaborative study by twelve collaborators in six laboratories. In the official method, hard frozen ice cream is immersed in a specially constructed overflow can filled with deodorized kerosene and the volume of the ice cream is determined by measuring the volume of kerosene displaced. In the new method, hard frozen ice cream is immersed in a container of fixed volume filled with water and the volume of water displaced is determined by weight loss. This study shows that the new method is more precise than the old one. It is therefore recommended that the new method be adopted as official, first action.
Collaborative Study of a Gas Chromatographic Determination of Methylene Chloride, Ethylene Dichloride, and Trichloroethylene Residues in Spice Oleoresins
Authors: Roberts Laura A 
Published: February 2020

Abstract
A method for the gas chromatographic determination of methylene chloride, ethylene dichloride, and trichloroethylene residues in spice oleoresins was studied collaboratively. The method employs a microcoulometric gas chromatograph fitted with a Porapak Q column and is based on the volatility of the solvent residues, their relative retention times on a polyaromatic bead chromatographic column, and their detectability by a halide-specific microcoulometric method. Recoveries were adequate when the method was closely followed; recoveries were erratic when collaborators deviated from the method. Further study is recommended.
Determination of Vitamins D2 and D3 in Pharmaceuticals by Gas-Liquid Chromatography
Authors: Murray T K , Erdody P , Panalaks T 
Published: February 2020

Abstract
A method is described for determining vitamin D in multivitamin preparations; in the method, vitamins D2 and D3 are isomerized with antimony trichloride and separated by GLC. Vitamins D,2 and D3 are differentiated and measured separately and one vitamin may be used as an internal standard for the other. Vitamin A is largely removed by partition chromatography but can be tolerated in the final dilution in a ratio of 1:1 with vitamin D. When the method was used for the assay of multivitamin preparations, the coefficient of variation was 3.2%.
Bacteriological Method for the Examination of Tree Nut Meats
Authors: Lanier John M 
Published: February 2020

Abstract
A collaborative study was made of a method used by the Food and Drug Administration for the bacteriological examination of tree nut meats. The method is based on enumeration and identification of Escherichia coli and on aerobic plate counts. Collaborative recoveries of E. coli were considered satisfactory, and the method is recommended for adoption as official, first action. The method for determining aerobic plate counts will be further studied.
Determination of Dicofol (Kelthane®) Residues in Fruits and Vegetables
Authors: Gunderson Ellis L 
Published: February 2020

Abstract
A colorimetric method for the determination of dicofol residues involves the extraction and cleanup procedures of the Mills, Onley, and Gaither method for chlorinated pesticides, with modification of the Florisil cleanup step. The determinative step is a modified Fujiwara alkaline pyridine reaction. The product of the Fujiwara reaction is treated with benzidine in formic acid, and the resulting colored solution is analyzed spectrophotometrically at 530 mμ. The method will detect as little as 5 μg dicofol and has been employed successfully in analysis of various fruits and vegetables, with recoveries of 93—100% at levels of 1, 2, and 5 ppm. Cleanup on all crops tested was adequate. It is recommended that studies on the method be continued, and that the method be studied collaboratively
Detection of Adulteration in Dark Colored Fruit Juices
Authors: Fitelson J 
Published: February 2020

Abstract
The official, first action paper chromatographic method for detecting adulteration in Concord grape juice has been applied to several dark colored fruit juices, including cherry, raspberry, blackberry, and strawberry. In contrast to the complicated anthocyanin patterns on the paper chromatograms of grape juices, these juices show simple patterns of one or two major red bands. Since most advUterants have more complicated anthocyanin patterns, they can be readily detected by this method, even at low concentrations. If adulteration cannot be detected by the anthocyanin patterns, it can usually be shown by the anthocyanidin patterns. In this paper chromatographic test, three separate anthocyanidin spots are formed. The dark colored juices tested here showed most of the anthocyanidin color in the central spot, whereas the possible adulterants showed other patterns. Therefore, mixtures will have abnormal anthocyanidin patterns in this test. Examples of both laboratory-prepared adulterated juices and some adulterated commercial juices are given.
Rapid Screening Method for Chick Edema Factor in Fats and Fatty Acids: 1967 Collaborative Study
Authors: Higginbotham G R , Ress John , Firestone David 
Published: February 2020

Abstract
A recently proposed improved rapid screening method for chick edema factor in fats was studied collaboratively by ten laboratories. The new procedure, a modification of the official electron capture method, reduces sample cleanup time by replacing the saponification step of the original procedure with a preliminary sulfuric acid cleanup step. Subsequent cleanup involves alumina column chromatography of the petroleum ether extract from sulfuric acid treatment, and gas chromatographic analysis at 200 °C of a specific polar alumina fraction. Gas chromatographic peaks with retention times vs. aldrin between 10 and 25 indicate the presence of chick edema factor. It is recommended that the modified procedure be adopted as official, first action.
Quantitative Gas Chromatographic Determination of Heroin in Illicit Samples
Authors: Grooms Julian O 
Published: February 2020

Abstract
A gas-liquid chromatographic method, using trimethyl silyl derivatives, is described for the quantitative determination of heroin in illicit samples in the presence of opium alkaloids such as morphine and monoacetylmorphine and common diluents such as lactose and procaine. Silylation of the illicit sample makes it possible to detect and identify some adulterants, namely, sugars such as lactose and mannitol, and procaine. The method provides a quick, accurate, and specific technique for determining heroin in illicit samples at concentrations over 5% with the optimum accuracy between 10 and 50%
Analysis of Sodium Diphenylhydantoin and Phenobarbital Combinations by Nonaqueous Titration
Authors: Agarwal Sura J P , Blake Martin I 
Published: February 2020

Abstract
A simple, nonaqueous titration procedure is described for the determination of sodium diphenylhydantoin and phenobarbital combinations. Preliminary separation of the components is unnecessary. The phenobarbital content is determined by direct titration in tert.-butyl alcohol, using sodium methoxide or triethyl n-butyl ammonium hydroxide as the titrant. The total acidity is determined by titration of the sample after passage through a cation exchange resin (Amberlite IRC-50). The sodium diphenylhydantoin content is obtained by difference. Quantitative recoveries were obtained for synthetic mixtures and commercially available dosage forms
Radioactive Lactose in Skim Milk Following Administration of Carbonyl-14C-Carbaryl to a Lactating Cow
Authors: Baron R L 
Published: February 2020

Abstract
Administration of 2 g carbonyl-14C-carbaryl to a lactating cow resulted in radioactive residues in milk of approximately 1 % of the administered dose. Analysis of the distribution of radioactivity in skim milk showed 13 and 87% of the radioactivity present as organic-soluble and water-soluble components, respectively. Crystallization of lactose from the water-soluble components resulted in removal of 90—95% of the 14C radioactivity. The data obtained indicate that following hydrolysis of the carbonyl-14- C-carbaryl, a small quantity of 14C02 was incorporated into lactose
Gaptan and Structurally Related Compounds: Thin Layer and Gas-Liquid Chromatography
Authors: Pomerantz Irwin H , Ross Ronald 
Published: February 2020

Abstract
Captan, folpet, and Difolatan® are structurally related fungicides. Major metabolites derived from these compounds are the imides: tetrahydrophthalimide and phthalimide. The epoxides of captan and Difolatan are possible alteration products which may form under conditions of weathering or degradative metabolism. A TLC method has been developed which differentiates between captan, folpet, Difolatan, tetrahydrophthalimide, phthalimide, captan epoxide, Difolatan epoxide, and tetrahydrophthalimide epoxide. The method is based upon chromatography on silica gel with 1% methanol in chloroform as solvent for development, followed by sequential color development of the resulting spots. N,NDimethyl - p - phenylenediamine, potassium permanganate, and chromic acid were the chromogenic sprays used. Lower limits of detection for these compounds were determined in the named TLC system. The GLC behavior of this group of compounds was also studied, utilizing both a 10% DC-200 on Gas Chrom Q (80—100 mesh) column and a mixed column of 10% DC-200:15% QF-1 (1:1) each on 100-120 mesh Gas Chrom Q. GLC retention times and response data were determined with an electron capture detector
Comparison of a Liquid Ion Exchange Electrode and the AOAC Method for Determining Calcium in Animal Feeding Stuffs
Authors: Allen R D , Hobley J , Carriere R 
Published: February 2020

Abstract
In the proposed method for determining calcium in animal feeds and ingredients, the ashed sample is dissolved in dilute HCl, pH is adjusted to 5.5—6.0 with KOH solution, and the solution potential is measured with an ion exchange calcium electrode. Statistical evaluation of the experimental data, as measured by the standard deviation and coefficient of variation, shows that the recovery and reproducibility of the electrode method compare favorably with the official AOAC method. Advantages of the proposed method are the reduction of analytical steps and the saving of analytical time.
Field Test to Determine Proper Heat Treatment of Animal Swill
Authors: Czech Fred P , Sunseri Alfred P 
Published: February 2020

Abstract
Properly cooked garbage is a widely accepted, economical, and good source of nutrition for hogs. However, incompletely cooked or raw garbage represents a real hazard as a source of contagious diseases among livestock. The simple, rapid, and reliable field test described in this paper can be used to determine whether swill has been cooked enough to destroy disease agents such as hog cholera virus. The test monitors the effect of cooking upon the survival of the common enzyme, acid phosphomonoesterase. Garbage exudate is incubated with the substrate phenolphthalein monophosphate. If present, the heat-labile enzyme reacts with the substrate to form phenolphthalein. The latter produces a red color at alkaline pH, indicating insufficient cooking of the hog swill. The test may be performed in the field at the cook-site, and a valid index of proper cooking can be obtained without the presence of a livestock inspector during cooking.
Instrumental Evaluation of Aflatoxin Resolution on TLC Plates
Authors: Pons Walter A , Goldblatt Leo A 
Published: February 2020

Abstract
An objective instrumental evaluation system is suggested for determining the degree of resolution of aflatoxins on TLC plates coated with silica gel. The plates are spotted with a standard containing the four aflatoxins, developed, and scanned with a densitometer equipped for fluorescence measurement. Numerical resolution factors are calculated from the recorder traces and used as an index of degree of separation of the aflatoxins.
Chemical Composition of Fruits
Authors: Boland Frederick E , Blomquist Victor H , Estrin Ben 
Published: February 2020

Abstract
Authentic data are presented on the chemical composition of strawherries, red raspberries, blackberries, black raspberries, boysenberries, and cranberries. Samples were analyzed for total soluble solids, ash, K2O, P2O5, invert sugar, protein, anhydrous citric acid, and amino acids.
Egg Content of Noodles by Quantitative Analysis of Characteristic Proteins of the Egg
Authors: Silano V , D’Errico Anna Maria , Micco Claudia , Muntoni F , Pocchiari F 
Published: February 2020

Abstract
A new method has been developed for determining the egg content of noodles. Extracts of noodles were prepared in 0.15M NaCl and fractionated by disk electrophoresis on polyacrylamide gel. In the electrophoretic patterns of extracts from noodles with different egg content, bands of proteins originating from eggs were found. The densitometric measurement of intensity of one of these bands (Mb = 0.21) permitted the quantitative evaluation of the egg content of noodles.
Fluorometric Determination of Sterols as Cholesterol in Egg Noodles: Collaborative Study
Authors: Roberts Laura A 
Published: February 2020

Abstract
A fluorometric method has been developed for the quantitative determination of per cent sterols as cholesterol in egg noodles. Sterol is extracted with chloroform from a ground composite, and an aliquot is subjected to a Liebermann-Burchard reaction followed by fluorometric measurement. Seven collaborators obtained 98.5-101% recoveries of sterols, and the fluorometric determination of sterols as cholesterol is recommended for adoption as official, first action.
An Improved Method for the Quantitative Determination of Coenzyme Q and α-Tocopherol in Rat Liver
Authors: Argrett Loretta C , Seward C R 
Published: February 2020

Abstract
A simple method for analyzing rat liver for CoQ and α-tocopherol is outlined. This method has distinct advantages over the previous methods described in the literature because the time-consuming steps of column chromatography and spectrophotometric assay of the many column fractions have been eliminated. The time required for sample analysis has been approximately halved. The method has four steps: (a) saponification of the tissue lipids in a nitrogenous atmosphere and extraction of the non-saponifiable lipid fraction, (b) TLC of the extract, (c) extraction of CoQ and α-tocopherol from their bands on the TLC plates, and (d) colorimetric assay of each compound. The bands after TLC were easily detected because of a fluorescent indicator, and the separation and recoveries were good.
Dursban Oxygen Analog: Determination in Fortified Milk and Body Tissues of Cattle
Authors: Ivey M C , Claborn H V 
Published: February 2020

Abstract
Electron capture gas chromatography is used to analyze milk and animal tissue extracts for the oxygen analog (diethyl O-3,5,6-trichloro-2-pyridyl phosphate) of Dursban®. Residues of 0.1 p pm were satisfactorily recovered from fat a n d muscle and 0.025 ppm from milk. Recoveries from brain, spleen, heart, kidney, and liver tissue averaged 62, 58, 24-40, 18, and 0%, respectively.
Comparison of a Phosphorimetric Procedure for Parathion on Celery with the Averell-Norris and Electron Capture Methods
Authors: Moye H Anson 
Published: February 2020

Abstract
A rapid and sensitive procedure to determine parathion on celery is described. Parathion is extracted with an isopropyl alcohol: hexane solvent mixture, hydrolyzed to p-nitrophenol with hydrogen peroxide in highly alkaline solution, and measured phosphorimetrically. Fortification levels of 0.08 to 60.0 ppm yielded recoveries between 79 and 112%.
Ultraviolet Absorption Spectrophotometry Method for the Determination of Morphine in Paregoric
Authors: Takazawa Futoshi 
Published: February 2020

Abstract
An ultraviolet absorption spectrophotometric method is described for the determination of morphine in paregoric. Morphine is isolated from a 5 ml paregoric sample by a modification of the USP XVII extraction procedure and then measured by ultraviolet absorption spectrophotometry. Factors affecting the precision and accuracy of the method are discussed.
Fluorometric Analysis of Sodium Fluorescein in Ophthalmic Solutions
Authors: Jekabsons Evalds 
Published: February 2020

Abstract
A collaborative study was conducted on a fluorometric method for sodium fluorescein in ophthalmic solutions. Using a standard curve prepared from hydrolyzed fluorescein diacetatc, the dye concentration was determined in a pH 9 buffer (excitation wavelength 460 mµ, emission wavelength 515 mµ). Recoveries for the four solutions were 96–104%. TLC on fluorescent silica gel sheets is used to identify sodium fluorescein, detect possible degradation products, and differentiate acriflavine from hydrochloride. It is recommended that the method be adopted as official first action.
Moisture in Cheese: Collaborative Study of a Distillation Method and Discussion of a Karl Fischer Procedure
Authors: Strange Theron E 
Published: February 2020

Abstract
Eleven laboratories studied a proposed method of determining moisture in cheese by distillation with a mixture of n-amyl alcohol and xylene and compared it with method 15.157. Samples from two Cheddar cheeses and two Blue cheeses were analyzed. There was reasonably good agreement between the two methods for moisture in Cheddar cheese. The distillation method gave lower and more consistent results for moisture in Blue cheese, and a proposed adaptation of the Karl Fischer tilration procedure gave still lower results.
Quantitative Determination of Lactic Acid and Succinic Acid in Foods by Gas Chromatography
Authors: Salwin Harold , Bond John F 
Published: February 2020

Abstract
Lactic and succinic acids are liberated from the sample with sulfuric and phosphotungstic acids, extracted with absolute ether, csterified with boron trifluoride-npropyl alcohol, and gas chromatographed on a diethylene glycol succinate column. Acctophenone is used as internal standard, and a dilution procedure is described for accommodating samples having high concentrations of lactic and succinic acids. Recovery data were obtained on whole egg samples with acids added in concentrations representative of decomposed eggs: up to 100 mg lactic acid and up to 60 mg succinic acid/100 g egg. Maximum absolute errors were 7.1 mg for lactic acid and 4.4 ing for succinic acid. Maximum percentage errors were 7.1 and 13.3, respectively. The method was also applied to beef, shrimp, and cottage cheese whey.
Gas Chromatographic Determination of Ethyl O,O-Dimethyldithiophosphoryl- 1-Phenyl Acetate in Technical Grade Cidial and Its 50% Liquid Formulation
Authors: Bazzi B , Abbruzzese L , Galluzzi G 
Published: February 2020

Abstract
A gas chromatographic method has heen developed for analysis of ethyl O,O-dimethyldithiophosphoryl- 1-phenyl acetate. The insecticide or a convenient amount of an insecticidal preparation is dissolved in toluene, together with a suitable internal standard, and analyzed by gas chromatography, using a thermal conductivity detector. The precision (P = 0.05) of the method is ±1.5% of the concentration found.
Collaborative Study of the Determination of Sodium and Potassium in Fish and Other Marine Products
Authors: Thompson Mary H 
Published: February 2020

Abstract
Collaborative studies on the flame photometric method for determining sodium and potassium in fishery products, using both dry-ash and wet-ash methods, indicate that both ashing methods are equally efficient and the choice of method depends upon the analyst. Both methods of preparing fishery product samples for flame photometric analysis are recommended for adoption as oflicial first action
Methods for Examination of Flavonoids in Fruits: Application to Flavonol Glycosides and Aglycones of Apples, Pears, and Strawberries
Authors: Duggan M Bonner 
Published: February 2020

Abstract
Extraction and isolation methods developed for flavonoids in fruits and fruit products include a choice of column trapping or solvent extraction, plus a method of isolating flavonoid compounds for GLC by selective lead precipitation, based upon control of pH. The methods were applied to apples, pears, and strawberries. Two-dimensional TLC on cellulose was used to compare flavonol glycoside patterns. GLC identification was based upon the identities and relative amounts of the flavonol aglycones, chromatographed as the trimethylsilyl derivatives. Free flavonol aglycones are shown to occur in damaged and/or decomposed fruit.
Collaborative Study of the Determination of Soluble Solids in Tomato Products by Refractive Index Expressed as Per Cent Sucrose
Authors: Lamb Frank C , Evans George 
Published: February 2020

Abstract
A collaborative study was conducted on a method for determining refractive index of tomato concentrates after filtration. A pectic enzyme preparation in dry form is added to undiluted concentrate to facilitate filtration and an optional incubation step is included for samples which are difficult to filter. Dilution with an equal weight of water containing the enzyme preparation is specified for samples which cannot be filtered satisfactorily without dilution. Standard deviations varied from 0.15% for a sample giving a reading of 24% sucrose at 20°C to 0.40% for a sample reading 44%. This agreement is comparable to that previously obtained on the official vacuum drying method. Results are reported from two laboratories using ultracentrifugation methods for obtaining clear serum. It is recommended that the filtration method be adopted as official first action and that the ultracentrifuge method be further studied.
Method for the Extraction of Extraneous Materials from Unground Cassia
Authors: Roaf Andree L , Brickey Paris M 
Published: February 2020

Abstract
A new method has been developed for the extraction of extraneous materials from unground cassia. Hydrochloric acid is used to remove adhering extraneous material from the bark; double sieving is used to separate larger pieces of bark from filth elements and smaller plant material; and extraction of extraneous material from plant debris is performed in a trap flask. Collaborative results were good, and the method is recommended for adoption as official first action.
TLC Identification of Four Artificial Sweeteners in Beverages: Collaborative Study
Authors: Korbelak Trean 
Published: February 2020

Abstract
Saccharin, the cyclamates, dulcin, and P-4000, added to seven flavors of commercial beverages, can be separated and identified by TLC on silica gel, using a solvent system of butanol, ethanol, ammonia, and water. Saccharin is detected as a fluorescent spot under shortwave UV radiation. Successive spraying with solutions of bromine, fluorescein, and N-1-naphtliyl-ethylenediamine dihydrochloride reveals cyclamate as a bright pink spot, dulcin as a brownish or blue spot, and P-4000 as a brown-pink spot. Concentrations as low as 0.004% saccharin, 0.05% cyclamate, 0.03% dulcin, and 0.002% P-4000 have been detected in extracts from commercial products spiked with sweeteners. Preservatives and coloring and flavoring materials did not interfere with accurate identification. Six collaborators correctly identified three different unknown sweetener mixtures used to spike six flavors of beverages, plus one unknown of a commercially artificially sweetened beverage. Product blanks were negative for artificial sweeteners. The method is relatively simple and rapid, and t h e detection characteristics of the sweeteners, as well as their Rf values, aid in identification. The method is applicable to any one or any combination of the four sweeteners and is recommended for adoption as official first action.