bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of Moisture in Dried Vegetables
Authors: Rader Bobby R
Published: February 2020

The determination of moisture in dried vegetables by a near-infrared speclrophotoraetric method, a Karl Fischer method, and a vacuum oven method was submitted to additional collaborative study. Results by the 3 methods showed good precision and agreement. The near-infrared and the Karl Fischer methods extract the moisture from the dried vegetables into dimethylformamide (DMF). In the near-infrared method the absorbance of the DMF solution is measured at 1.92 μ and compared to a standard curve. In the Karl Fischer method an aliquot of the DMF solution is added to formamide and titrated with the Karl Fischer reagent. The Karl Fischer and near-infrared methods are more specific than the vacuum oven method and can be used for a greater variety of samples. Both the Karl Fischer and near-infrared methods are recommended for adoption as official, first action.
Identification of Plant Material by Its Phenolic Content
Authors: Duggan M Bonner
Published: February 2020

Methods have been developed to extract and chroniatograph phenolic constituents of Mains sylvestris and Pyrus communis fruits. Differences in the occurrence of flavonoid compounds between the two fruits and between pulp and peel in a given fruit were compared; the flavonol glycosides most conveniently demonstrated the differences. Five major and three minor flavonol glycosides from Stayman apples and two major and two minor ones from Packingham pears were separated by thin layer chromatograpliy. All of the major and some of the minor compounds were also described by ultraviolet absorbance spectra. Studies show that fruits can be distinguished on the basis of chromatographic patterns of the flavonol glycosides and that the results can be confirmed by their ultraviolet absorbance spectra
Assay for Vitamin C: A Collaborative Study
Authors: Deutsch Mike J
Published: February 2020

A collaborative study was conducted to evaluate the mierofluorometric assay for vitamin C. Comparative assays for vitamin C were made, using a modified 2,6-dichloroindophenol assay and the 2,4-dinitrophenylhydrazine method. Results by the fluorometric method were good. Both the mierofluorometric assay and the modified 39.040 method were recommended for adoption as official, first action.
Collaborative Study of a Method For The Determination of Caffeine in Nonalcoholic Beverages
Authors: Johnson Arthur R
Published: February 2020

A spectrochromatographic procedure for the determination of caffeine based upon modifications of the original Levine procedure was subjected to a collaborative study. Recoveries were generally better than 90%. The results indicate that the method is accurate for the determination of caffeine in nonalcoholic beverages. It is recommended that the method be adopted as official, first action.
Detection of Chick Edema Factor in Fats and Fatty Acids by Electron Capture Gas Chromatography
Authors: Higginbotham G R , Firestone David , Chavez Linda , Campbell A D
Published: February 2020

An electron capture gas chromatographic screening test has been developed for detecting chick edema factor in fats and fatty acids. The procedure involves extraction of unsaponifiables from 10 g fat, alumina column chromatography of the unsaponifiables, sulfuric acid cleanup of the third alumina fraction (25% ethyl ether in petroleum ether), and electron capture gas chromatography at 200°C. Gas chromatographic peaks with retention times vs. aldrin between 10 and 25 are indicative of thepresence of chick edema factor. The screening test has been evaluated by two collaborative studies, and results indicate that the method is suitable as a screening test for chick edema factor.
A Comprehensive Nitrogen Method
Authors: Gehrke Charles W , Ussary James P , Perrin Carrol H , Rexroad Paul R , Spangler William L
Published: February 2020

A single comprehensive nitrogen method applicable to all fertilizers and to all forms of fertilizer nitrogen has been developed. The method utilizes untreated chromium metal powder in an acid medium to reduce nitrates. It quantitatively reduced nitrates alone, nitrates in the presence of organic matter, and nitrates in samples with high C1"/N03_ratios. Quantitative results were obtained with both solid and liquid fertilizer samples and with highly refractory organic samples. When subjected to the ruggedness test of Youden the method was "rugged."
Determination of 4(4-Chloro-2-suIfo-5-toIylazo)-l-naphthol in
D&C Red Nos. 8 and 9
Authors: Stein Charles
Published: February 2020

A procedure is described for determining small amounts of 4(4-chIoro-2-suIfo-5-tolylazo)- l-naphthol in D&C Red Nos. 8 and 9. The subsidiary color is separated from D&C Red Nos. 8 and 9 by precipitation and extraction under controlled conditions of alkalinity and salt concentration, and is measured spectrophotometrically. Samples containing up to 1.5% of the subsidiary color can be determined by this procedure. Recoveries of 0.5 to 1.5% added color ranged from 80 to 94%
Selective Residue Determination of Sulfur-, Halogen-, and
Phosphorus-Containing Pesticides by Helium-Plasma
Emission Spectrometry
Authors: Bache Carl A , Lisk Donald J
Published: February 2020

An intense microwave-powered helium plasma was previously found to effectively excite sensitive atomic emission in sulfur, bromine, chlorine, iodine, and phosphorus in organic pesticides and drugs. In the work reported, helium-plasma emission spectrometry coupled with gas chromatography has been applied to a wide range of samples for analysis of pesticide residues. Monitoring atomic line emission provides sensitive, selective detection of sub-nanogram quantities of these major heteroelements in crops containing organic pesticides
Determination of Glycerol in Cosmetics by GLC. II. Collaborative Study
Authors: Gross Frederick C
Published: February 2020

The results of the collaborative study of the GLC method for glycerol in cosmetics show that the conditions originally specified must be modified. Some lots of the SAIB column packing bleed excessively at the specified temperature (200°C). Further work indicates that this difficulty can be eliminated by operating the SAIB column at 170-180 °C
High Resolution Infrared Spectra of Some Naturally Occurring Sesquiterpene Hydrocarbons
Authors: Wenninger John A , Yates Ronald L , Dolinsky Meyer
Published: February 2020

High resolution infrared spectra in the region from 4000 to 300 cm- 1 are presented for 36 sesquiterpene hydrocarbons. The compounds were isolated from commercial essential oils and purified by gas chromatographic techniques. The gas chromatographic retention times relative to isodurene as an internal standard and the five strongest infrared hands in the 1250— 300 cm- 1 region are also tabulated
Separation and Identification of Minor Alkaloids of
Strychnos nux vomica
Authors: Marini-BettÓlo G B , Monache F Delle , Brovetto A Gelabert de , Corio E
Published: February 2020

The various alkaloids of Strychnos nux vomica L. are separated and identified by the use of silica gel or alumina columns and/or thin layer plates. The groups correspond to these three: strychnine, pseudostrychnine, and icajine. Alkaloidal composition of the column chromatographic eluates and Rf values for the various TLC solvent systems are given.
Studies on the AOAC Tuberculocidal Test
Authors: Heister D , Shaffer C H , Hill M , Ortenzio L F
Published: February 2020

In vitro studies of the official, final action tuberculocidal test with ethyl and isopropyl alcohols confirmed previous results by the in vivo challenge procedures on naturally occurring infectious strains of Mycobacterium tuberculosis. Simulated use studies on sputum from 12 patients with active cases of pulmonary tuberculosis indicate that the end point in this method will provide a reasonably accurate index of tuberculocidal effectiveness in actual use
Determination of sec-Butylamine Residues in Fruit
Authors: Day E W , Holzer F J , Tepe J B , Eckert J W , Kolbezen M J
Published: February 2020

sec-Butylamine residues in certain fruit can be analyzed as follows: The amine is distilled from the tissue, reacted with 1- fluoro-2,4-dinitrobenzene, and determined by gas chromatography with an electron affinity detector. Dimethylamine interferes but can be separated from sec-butylamine by thin layer chromatography prior to the final measurement. Of 65 pesticides studied, only ferbam, thiram, and ziram, which produce dimethylamine upon hydrolysis, interfere to any degree with the determination
Detection and Differentiation of Cod Meat Substituted for Crabmeat in Frozen Crab Products
Authors: Freeman C C
Published: February 2020

Adulteration of frozen crab products with cod meat can be detected by macroscopic examination. Cod meat, when held in the path of a focused beam of light, forms a brilliant display of colored patterns whereas crabmeat does not. Cooking does not affect this phenomenon. Preliminary investigation indicates that fish, in general, possess the same refractive ability as cod to form the color patterns, whereas shellfish, in general, like crab, do not.
Method for the Extraction of Extraneous Materials from Ground Cinnamon
Authors: Roaf Andree , Brickey Paris M
Published: February 2020

A new method has been developed for the extraction of extraneous materials from ground cinnamon. In the method, hydrochloric acid is used to disperse gel formations, wet sieving is used to eliminate the dispersed gel, and a percolator replaces a trap flask to separate the extraneous material from cinnamon tissue. Collaborative results were good, and the method is recommended for adoption as official, first action.
Rapid Method for the Extraction of Light Filth from Peanut Butter
Authors: Gecan John S , Brickey Paris M
Published: February 2020

A method has been developed for the extraction of light filth from peanut butter. The new method eliminates the petroleum ether and chloroform treatments in 36.021 and the pancreatin digestion in 36.022. Results are comparable to the official methods, and analysis time is reduced by one-half. The method is recommended for adoption as official, first action.
Polarographic Determination of Fumaric Acid in Foods
Authors: Taylor James E , Blomquist V H
Published: February 2020

The previously reported polarographic method for determining fumaric acid in foods has been revised and subjected to collaborative study. Interferences from naturally occurring substances were kept to a minimum by using a 25.00 g sample of juices. Seven types of samples were sent to collaborators: grape jelly (0.10% added fumaric acid) and apple, lemon, orange, pineapple, sauerkraut, and tomato juices with 0.05, 0.10, and 0.50% added fumaric acid. Analysis at the 0.05 and 0.10% levels indicated a 95 % confidence limit of ± 0.003 about the means 0.05 and 0.10, respectively, while results from the 0.50% level indicated ± 0.01 about its mean of 0.48. It is recommended that the method be adopted as official, first action.
Analysis for Aflatoxin M in Milk
Authors: Masri M S , Page J R , Garcia V C
Published: February 2020

Various extraction techniques were tried for the analysis of aflatoxin M in dried milk. Waring Blendor extractions with methanol containing varying concentrations of water were compared. The use of 2 0% water in methanol and defatting of the filtered extract with low boiling petroleum ether are recommended. The partitioning of aflatoxin M between chloroform and aqueous methanol extracts was tested, using different concentrations of water in methanol for the upper phase, and different volume ratios of upper to lower phases. In these partition experiments attention was paid to completeness of extraction of aflatoxin M and the amount of residue in the chloroform extracts. The use of water:methanol ( 1 : 1 , v/v) for the upper phase and three chloroform extractions, each equal to ½ the volume of the upper phase, are recommended. Certain cleanup procedures of the chloroform extracts (wash and column cleanup) were suitable for estimation of aflatoxin M (M1 plus M2, if present) after thin layer chromatography.
Survey of Green Coffee for Potential Aflatoxin Contamination
Authors: Levi Collete P , Borker Emanuel
Published: February 2020

A method for the detection and estimation of aflatoxin B1 in green coffee beans is described. According to the AOAC method, the toxin is extracted with aqueous methanol: hexane and the extract is cleaned up on a Celite column. The extract is further purified on a Florisil column and is then chromatographed on thin layer plates. The estimated limit of detection of the method is 2 μg aflatoxin/kg green coffee. About 75% aflatoxin B1 added to green coffee was recovered. The method was used in a survey of suspect samples of green coffee. No aflatoxin was detected in 58 samples originating in 10 producing countries. Preliminary studies with a new extraction solvent (dimethyl sulfoxide:benzene, 30:50) and a Florisil cleanup appear promising. About 85% aflatoxin B1 added to green coffee was recovered.
Colorimetric Determination of Benzocaine in Drugs
Authors: Myrick James W
Published: February 2020

A colorimetric determination of benzocaine by a modified Bratton-Marshall procedure has been developed for ear drops in water-soluble bases, suppositories in water-soluble bases, and throat lozenges. The method is applicable to concentrations normally found with these materials and does not require extensive cleanup. Other primary aryl amines, alkali iodides, and antipyrine in concentrations over 10 times the benzocaine content interfere in the method. Collaborative results indicate recoveries averaging 98.4—99.4% with standard deviations of 2.12-2.40%. It is recommended that the method be adopted as official, first action.
Collaborative Study of a Method for the Determination of Antipyrine and Benzocaine in Glycerol and Propylene Glycol Bases
Authors: Krause Richard T
Published: February 2020

A method for antipyrine and benzocaine, This Journal 50, 685-688 (1967), was studied by ten collaborators on five simulated commercial preparations at levels of 49—54 mg antipyrine/ml and 10—51 mg benzocaine/ml. The antipyrine and benzocaine are separated by column partition chromatography: antipyrine is retained on a ferric chloride column, and benzocaine is retained on a hydrochloric acid column. Maximum absorbances are determined on chloroform eluates at 272 and 283 mμ for antipyrine and benzocaine, respectively. Infrared spectra of the residues are determined in potassium bromide for identification of the drugs. The average recovery for antipyrine was 99.3 ± 1.80%, and for benzocaine, 99.0 ± 1 . 6 0 % . Infrared spectra submitted by collaborators corresponded to the reference standards and showed no interfering peaks. The method, with a slight change in the preparation of the standard solutions, is recommended for adoption as official, first action.
Oscillopolarographic Determination of Parathion, Paraoxon, and p-Nitrophenol in Fortified Canned Peaches Following Thin Layer Chromatography
Authors: Hearth Fred E , Ott Daniel E , Gunther Francis A
Published: February 2020

A procedure combining thin layer chromatography and oscillopolarography has been developed for the separation and microdetermination of parathion, paraoxon, and p-nitrophenol in admixture as residues in fortified canned peach extractives. The use of anthracene as an internal standard for aiding in the location of these compounds on TLC plates is proposed and discussed. This method responds to about 0.5 ppm each for the three compounds with a starting sample of 10 g peaches. While the oscillopolarograph is a very precise instrument, the precision obtainable from the total method is TLC dependent.
Determination of Sugar in Plant Materials: Measurement of Unreduced Copper by Atomic Absorption Spectrometry
Authors: Potter A L , Ducay E D , Mccready R M
Published: February 2020

An atomic absorption spectrophotometer was used for the quantitative analysis of reducing sugars by determining unreduced copper. Copper reduced in alkaline solution by sugar forms insoluble Cu2O. The Cu20 was centrifuged from the solution, and the unreduced copper in solution was measured with an atomic absorption spectrophotometer. The concentration of sugar present in test solutions was determined from a working curve prepared from known amounts of sugar.
Spectrophotometric Determination of Raceophenidol in Feed at Very Low Levels
Authors: Pratt Edward L , Auerbach Morris E
Published: February 2020

Raceophenidol in feed at concentration levels intended for growth promotion of poultry can be estimated by a curvature inversion measurement related to the ultraviolet spectrum of derived p-methylsulfonylbenzaldehyde. The drug can be accurately measured at the 0.0005% level. Collaborative studies on the method showed an average value of 94 ± 10% of claim. The method is recommended for adoption as official, first action.
Collaborative Study of the Analysis of Molasses and Molasses Products
Authors: Katesitis Boris
Published: February 2020

A collaborative study was conducted to investigate the methods of sampling and sample preparation of food and feed grade liquid and dried molasses in relation to sugar analysis. The effects of the sample size and solution treatment with EDTA and potassium oxalate were investigated. Lane- Eynon standard and constant volume methods were used to determine invert sugar and total sugar as invert. Results of analyses by collaborators were in good agreement. The various treatments studied did not affect the precision of the analysis. The methods are recommended for adoption as official, first action.
Collaborative Study for Fluorine in Feeds
Authors: Ritchie George D
Published: February 2020

A method for determining fluorine in feeds was studied collaboratively. The sample is ashed with saturated magnesium acetate as a fixative, and the fluoride ion is isolated by the Willard-Winter distillation. The fluoride concentration of the distillate is measvired spectrophotometrically at 570 imt by its bleaching effect on zirconyl- SPADNS dye reagent. Nine collaborators participated in the study on three commercial feed samples containing fluorine levels of 0.006, 0.012, and 0.055% and a National Bureau of Standards phosphate rock sample containing 3.4% fluorine. Because of the lack of precision and the large standard deviations, it is recommended that the study be continued.
Collaborative Study of Minerals in Feeds by Atomic Absorption Spectrophotometry
Authors: Heckman Mary
Published: February 2020

Eleven laboratories collaboratively studied the analysis of feeds for zinc, manganese, iron, and copper by atomic absorption spectrophotometry. Five feeds and one mineral mixture were analyzed. The feed samples were prepared by both dry ashing and wet digestion. Samples were analyzed chemically for manganese and iron. Results indicate the method is suitable for zinc, manganese, and iron. Further work is needed on the determination of copper. The method for atomic absorption analysis of feeds for calcium and magnesium (recommended too late for action in 1966) and the method for zinc, manganese, and iron are recommended for adoption as official, first action.
Estimation of Arecoline: A Rapid Distillation Method
Authors: Nambudiri E Sankaran
Published: February 2020

The extraction procedure for estimation of arecoline in areca nut is lengthy and not suitable for routine use. A method, based on the steam volatility of arecoline, has been standardized; it is simple and rapid for routine estimation of arecoline in areca nuts and arecoline hydrobromide in drugs and gives maximum and consistent recovery.
Collaborative Study of a Method for the Determination of Weight Per Unit Volume of Packaged Ice Cream
Authors: Habeger Larry E
Published: February 2020

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

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

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%.
Determination of Secondary and Minor Plant Nutrients in Fertilizers by Atomic Absorption Spectrophotometry. IV.
Authors: Mcbride C H
Published: February 2020

The results of three previous collaborative studies were reviewed and recalculated. On this basis, the atomic absorption spectrophotometric method is recommended for adoption as official, final action for calcium, copper, iron, magnesium, manganese, and zinc.
Bacteriological Method for the Examination of Tree Nut Meats
Authors: Lanier John M
Published: February 2020

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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.
Determination of Cyclohexylamine in Various Artificially Sweetened Foods and Artificial Sweeten
Authors: Howard John W , Fazio Thomas , Klimeck Barbara A , White Richard H
Published: February 2020

Procedures for the determination of cyclohexylamine in various dietetic products (carbonated beverages, dry beverage bases, canned fruits, fruit juice drinks, liquid and dry weight control formulations, and food sweetener preparations) and in sodium and calcium cyclamates have been developed. Recoveries were as follows: dietetic products 90-100% at the 0.2 ppm level, and sodium and calcium cyclamates 90-100% at the 2.0 ppm level. Cyclohexylamine was isolated from the following products at the indicated levels: carbonated beverages 0.0-6.5 ppm, dry beverage bases 0.0-480 ppm, canned fruits 0.3-0.9 ppm, fruit juice drink 0.7 ppm, liquid and dry weight control formulations 0.0-2.8 ppm, liquid and dry base food sweetener preparations 1.4-95 ppm, and cyclamates 3.8-54 ppm. The presence of cyclohexylamine was confirmed by either infrared spectrophotometry or mass spectrometry.
Rubidium Sulfate Flame Detector: Effect of Design of Alkali Source and Anode on Sensitivity and Stability
Authors: DeLoach Hiroko K , Hemphill D D
Published: February 2020

An improved alkali-flame detector using pure rubidium sulfate and an anode of new design were optimized for the quantitative determination of organophosphate pesticides. The performance of this detection system was evaluated for response to organophosphate standards, noise level, fluctuation of baseline, short- and long-term reproducibility at low pesticides levels, conditioning time of instrument, life and physical stability of alkali source, and required frequency of detector cleaning. Under optimum conditions the detector was sensitive to 1 pg pesticide standard. To define the parameters of the alkali flame detector, studies were made of different designs of the alkali source which influence flame configuration and the relationship of the position and shape of the anode to the flame. The most important parameter appears to be the method of introducing alkali vapor.
Determination of Total Phosphate and Identification of Acid-Insolubles in Superphosphoric Acid
Authors: Carel A B , Jordan D E
Published: February 2020

Discrepancies in the analysis of superphosphoric acid for iron, aluminum, and phosphorus are found to be directly related to the digestion procedure used for sample preparation. Various acid digestions and combined acid-base digestion data are discussed. Chemical and atomic absorption data are combined to confirm the structure of the acid-insoluble material identified by X-ray diffraction analysis. Recommended digestion procedures are included for the quantitative analysis of superphosphoric acid for iron, aluminum, and phosphorus.
Automated High Precision Determination of Phosphorus at Concentrations of 0.01 to 7.5 mg P2O5/ml
Authors: Jordan Donald E
Published: February 2020

An automatic P2O5 method of wide concentration range which analyzes phosphate from 0.01 to 7.5 mg P2O5/ml without range expansion and with in situ dilution is described. Parameters involving elimination of sample-wash crossmixing and modification of known published technology are described. Precision at 40 samples/hr throughout the concentration range from 0.1 to 75% P2O5 is better than +0.3% relative and accuracy is better than +0.4% relative.
Chemical Composition of Fresh Elderberries
Authors: Taylor James R , Fernandez-Flores E
Published: February 2020

Fresh elderberries were analyzed for amino acids by formol titration, insoluble solids, soluble solids, ash, K2O, P2O5, invert sugar, l-malic acid, total polyphenolics, protein, and titratable acidity calculated as citric acid. Authentic data are tabulated.
Moisture in Honey: Review of Chemical and Physical Methods
Authors: White Jonathan W
Published: February 2020

A critical review is presented of the determination of moisture in honey by chemical (Karl Fischer) and several physical methods, including evaporation, distillation, refractometry, density, and viscosity. Methods are compared for precision and accuracy, and interrelationships are discussed. Wedmore’s interpretation of Chataway’s specific gravity results is shown to be based on a misconception.
Review of Methods for Mercury in Pesticide Formulations
Authors: Launer James E
Published: February 2020

Outlines are given for mercury methods that have been accepted by CIPAC. One method separates mercury from other pesticides by dissolving the pesticide in hot glacial acetic acid and amalgamating the mercury on zinc. Another method dissolves mercury in hydrochloric acid and separates it from other pesticides by hydrogen sulfide precipitation or by amalgamation on zinc. Other oxidation procedures are given for decomposition of mercury compounds. Further study is recommended for the method in which mercury is released with fuming sulfuric-nitric acids and determined with thiocyanate titration.