bluuebunny/crossref_metadata_2025_split huggingface dataset:
Moisture Analysis of Forage by Near Infrared Reflectance Spectroscopy: Preliminary Collaborative Study and Comparison Between Karl Fischer and Oven Drying Reference Methods
Authors: Windham William R , Barton Franklin E , Robertson James A 
Published: February 2020

Abstract
A collaborative study of moisture analysis by neai infrared reflectance spectroscopy (NIRS) has been completed involving 5 laboratories and 20 forage samples. Near infrared reflectance spectroscopy calibrations for moisture were developed in the Associate Referee's laboratory from Karl Fischer (KF) and AOAC air oven (AO) (135°C for 2 h) moisture methods, respectively, and transferred to each collaborating laboratory's NIRS instrument. NIRS moisture data were validated with KF data from the Associate Referee's laboratory and AO data from each collaborating laboratory. The standard error of analysis of KF data by NIRS KF determination and AO data by NIRS AO determination ranged from 0.25 to 0.48% and from 0.74 to 1.88%, respectively. The standard errors between laboratories for NIRS KF and NIRS AO determinations were 0.2" and 0.39%, respectively. The standard error between moisture analyses by NIRS KF and NIRS AO calibrations, averaged across laboratories, was 0.42%. In addition, the standard error between laboratories for the AOAC AO method was 0.63%. The increase in standard error for the AOAC AO method was due to the random and systematic errors associated with the gravimetric techniques. The results indicate that NIRS analysis can accurately and precisely deterrr ine the moisture content of forages and forage crops because of th« very strong absorbance of water in the near infrared region.
Gas Chromatographic Determination of the Monosaccharide Composition of Plant Cell Wall
Preparations
Authors: Harris Philip J , Blakeney Anthony B , Henry Robert J , Stone Bruce A 
Published: February 2020

Abstract
A simplified procedure is described for determining the monosaccharide composition of plant cell wall ("fiber") preparations. The preparations are hydrolyzed using a 2-stage sulfuric acid method. The monosaccharides released are rapidly reduced and acetylated to produce alditol acetates, which are separated by capillary gas chromatography. This procedure has been applied to the analysis of fiber preparations from a variety of animal feeds. The monosaccharide composition of the fiber preparations varied among feeds from different sources, indicating the usefulness of this method in characterizing fiber preparations in nutritional studies.
Determination of /V-Nitrosodipropylamine in Trifluralin Emulsifiable Concentrates Using
Minicolumn Cleanup and Gas Chromatography with Thermal Energy Analyzer
Authors: Wotherspoon Dave , Hindle Ralph 
Published: February 2020

Abstract
A quick method for determining /V-nitrosodipropylamine (NDPA) levels in trifluralin emulsifiable concentrate formulations is described. At least 18 samples can be analyzed at one time in a minimum of fumehood space, with up to 90% savings on solvents and materials. A sample aliquot is mixed with a solution containing nitrosamine recovery standards, and nitrosamines are separated by minicolumn cleanup. Internal standard is added directly to the eluate containing the nitrosamines, and levels are determined by gas chromatography with thermal energy analyzer. Recoveries of spiked nitrosamines ranged from 98 to 102%. Coefficients of variation for samples containing 0.5 ppm NDPA are 13%. Minimum detectable limit, calculated as 3 times the noise, is 0.06 ppm. Comparison with the method formerly used by this laboratory shows no significant difference in the analytical results at 95% confidence limits, and control experiments were performed to ensure that there was no artifact formation of NDPA.
Liquid Chromatographic Determ [nation of Available Lysine in Soybean and Fish Meal
Authors: Rabasseda Joan , Rauret Gemma , Galceran Teresa M 
Published: February 2020

Abstract
A method for the determination of available lysine on the basis of the reactivity of the e-amino group with fluorodinitrobenzene (FDNB) has been optimized. Hydrolysis is performed in closed vessels in an autoclave. Conditions for different meals were established by using a modified sequential simplex method. Hydrolysis for 4 h was sufficient for the meals studied—soybean and fish. The use of liquid chromatography to determine available lysine was studied, and optimum conditions were established for separation and quantitation of e-DNB-lysine. The proposed method is faster, more accurate, and more precise than commonly used methods
Improved Method for Determination of Chlorothalonil and Related Residues in Cranberries
Authors: El-Nabarawy1 Ibrahim M , Carey William F 
Published: February 2020

Abstract
Tetrachloroisophthalonitrile (chlorothalonil) was applied under controlled conditions in 1985 to a cranberry bog for fungus control and for residue studies. Randomly selected samples of cranberries were analyzed for residues of chlorothalonil, its metabolite 4-hydroxy- 2,5,6-trichloroisophthalonitrile, hexachlorobenzene, and pentachlorobenzonitrile by extraction, methylation, Florisil column cleanup, and electron capture gas chromatography. Because of interferences in the GC determinative step, previously reported methodology was modified. The total residues found in the test samples were well below the permissible limit for the parent and related compounds.
Development of Porcine Rapid Identification Method (PRIME) by Modified
Agar-Gel Immunodiffusion
Authors: Cutrufelli Mark E , Mageau Richard P , Schwab Bernard , Johnston Ralph W 
Published: February 2020

Abstract
A porcine rapid identification method (PRIME) has been developed for detection of pork in a wide variety of meat products. The test is an adaptation of previously developed field screening immunodiffusion tests for beef and poultry detection. The PRIME test was demonstrated to be specific, sensitive, and accurate in the analysis of samples in the laboratory and in a commercial meat processing establishment.
Determination of Diacetyl in Butter as 2,3-Diaminonaphthalene Derivative, Using a Fluorometric Procedure or Reverse Phase Liquid Chromatography with Fluorescence Detection
Authors: Damiani Pietro , Burini Giovanni 
Published: February 2020

Abstract
Two procedures, one fluorometric and the other reverse phase liquid chromatographic, for determination of a derivative of diacetyl are described. Exploratory work on diacetyl standard solutions to establish the best conditions for the derivatization with 2,3-diaminonaphthalene (DAN) to yield 2,3-dimethylbenzo[g]-quinoxaline (DMBQ) is discussed, as well as the fluorescence characteristics of the DMBQ derivative. Diacetyl was determined in 10 commercial butter samples by the proposed procedures and by other known methods (determination of o-phenylenediamine and 3,3-diaminobenzidinederivatives). Recoveries from butter samples spiked with known amounts of diacetyl ranged from 96.9 to 101.8% (with CVs ranging from 0.3 to 2.1%) for the fluorometric procedure and from 96.9 to 102.7% (with CVs ranging from 0.5 to 2.4%) for the chromatographic procedure. These results agree well with those obtained with o-phenylenediamine and 3,3-diaminobenzidine methods on the same butter samples. The proposed methods have the advantages of improved detectability and specificity.
Determination of Polychlorinated Biphenyls in Sediments, Using Sonication Extraction and
Capillary Column Gas Chromatography-Electron Capture Detection with Internal Standard
Calibration
Authors: Dunnivant Frank M , Elzerman Alan W 
Published: February 2020

Abstract
A sonication technique is presented for the extraction of polychlorinated biphenyls (PCBs) from sediments. In addition, a quantitation scheme is described which allows peak-specific and, in many cases, congener-specific determination of PCBs. PCBs are quantitated by capillary column gas chromatography-electron capture detection, with internal standard calibration. Results utilizing sonication extraction were compared with those obtained by Soxhlet and steam distillation extractions of 3 U.S. Environmental Protection Agency (EPA) quality control sediment samples and 3 lake sediments known to be contaminated with PCBs. Environmental lake sediments were extracted wet, with no drying prior to extraction. Recoveries by each technique varied depending on the sediment sample being extracted and degree of chlorination of PCB congeners. With proper selection of extraction solvent, the sonication technique can recover amounts of PCBs equivalent to and sometimes greater than recoveries by the Soxhlet or steam distillation techniques. A 24-h quiescent period in the extraction solvent between 2 sonications improved extraction efficiency for 2 freeze-dried sediments but did not affect results obtained for 3 environmentally contaminated sediments that were extracted without drying. Replacement of Soxhlet extraction with the sonication technique results in reduced sample preparation time, decreased volumes of solvents and sample, and substitution of common laboratory glassware in place of fragile, expensive Soxhlet glassware. Sonication extraction can also improve precision compared with Soxhlet extraction
Fluorogenic Assay for Rapid Detection of Escherichia coli in Chilled and Frozen Foods:
Collaborative Study
Authors: Moberg Lloyd J , Wagner Mary K , Kellen Lisa A 
Published: February 2020

Abstract
A collaborative study was conducted to compare a proposed LSTMUG method with the AOAC official method for Escherichia coli detection. E. coli produces an enzyme, β-glucuronidase, which cleaves the substrate, 4-methyl-umbelliferyl-β-D-glucuronide (MUG), to yield a fluorescent end product. Incorporation of the MUG substrate into lauryl tryptose broth (LST) enables a rapid quantitative method for screening E. coli, which is detected by fluorescence of the medium under longwave UV light. In this collaborative study, 5 food samples, 2 frozen (entree sauce/gravy and dairy topping) and 3 chilled (hamburger, pork sausage, and cheese), were tested for E. coli detection by 17 collaborating laboratories. Results indicate that the LST-MUG method is equal to or better than the current AOAC method for detecting E. coli. The LST-MUG method has been adopted official first action
Survey of Vitamin Content of Fortified Milk
Authors: Tanner James T , Smith Jeffrey , Defibaugh Phillip , Angyal Gerald , Villalobos Melina , BUENO Martin P , Mcgarrahan Eugene T , Michael Wehr H , Muniz Juan F , Hollis Bruce W , Koh Younghan , Reich Peter , Simpson Kenneth L 
Published: February 2020

Abstract
This paper summarizes work done by 4 different laboratories on the vitamin content of milk. Riboflavin, vitamin A, and vitamin D were assayed in whole, 2%, and skim milks that had been fortified. In general, the adherence to label claim decreased with decreasing fat content. This may be due to methods and stage of vitamin addition prior to processing
Historical Perspectives on Methodology to Detect Listeria monocytogenes
Authors: Donnelly Catherine W 
Published: February 2020

Abstract
While recognized as a causative agent of illness in animals and humans for some time, the foodborne role of Listeria monocytogenes is a new and emerging one. This review briefly summarizes the historical developments in methodology used to detect the presence of L. monocytogenes. Although clinical procedures exist, these procedures do not consider isolation of Listeria from heavily contaminated environments. Federal agencies such as the U.S. Food and Drug Administration and the U.S. Department of Agriculture have defined protocols for the isolation of Listeria from dairy and meat products, respectively. Each of these protocols, and current problems common to all methods for the isolation of Listeria from food products, are discussed. Finally, future challenges with respect to improvement in our abilities to recognize, isolate, and rapidly identify Listeria in foods are presented
Microbial Diffusion Assay for Antibiotics in Feeds Using a Simplified Design
Authors: Brady Marietta Sue , Katz Stanley E 
Published: February 2020

Abstract
Results are compared for the microbiological analysis of antibiotics in feeds using the AOAC plate diffusion assay and the simplified 2-plate assay. Five antibiotics, bacitracin, chlortetracycline, oxytetracycline, penicillin, and streptomycin, were used to supplement feed extracts at levels of 100 and 25 μg antibiotic/g feed (bacitracin at 100 jug/g only). For bacitracin at the one level and for penicillin at both levels, the 2-plate design yielded significantly more accurate results than those of the AOAC assay. The same was true for the 25 μg/g level of oxytetracycline and the 100 μg/g level of streptomycin. For streptomycin at the 25 μg/g supplementation, the AOAC assay results showed better accuracy. There was no significant difference in results between the 2 designs for oxytetracycline at 100 fig/g and chlortetracycline at either level. The accuracy and precision of the results for the 2-plate design are equivalent to or better than those obtained using the AOAC design; in addition, the 2-plate assay is less labor-intensive, is more cost-effective, and is able to determine reasonable conditions of similarity.
Rapid Procedure for Determination of Nicarbazin Residues in Chicken Tissues
Authors: Parks Owen W 
Published: February 2020

Abstract
A procedure is described for the quantitation of nicarbazin residues in chicken tissues. The method includes extraction of tissue with chloroform-ethyl acetate-dimethyl sulfoxide (50 + 50 + 0.8), adsorption on neutral alumina, and subsequent elution of the residues with methanol-pH 6.0 phosphate buffer (1 + 1). Extracts are separated on a 15 cm, 5 μm C18 column with methanol-pH 6.0 phosphate buffer (6.5 + 3.5) as the mobile phase. The dinitrocarbanilide portion of the complex is detected and quantitated with an electrochemical detector in the reductive mode. Recoveries, based on dinitrocarbanilide, were greater than 95% in liver, breast, and thigh muscle tissues fortified with 0.25-8.0 ppm nicarbazin.
Apple Juice Composition: Sugar, Nonvolatile Acid, and Phenolic Profiles
Authors: Lee Hyoung S , Wrolstad Ronald E 
Published: February 2020

Abstract
Apples from Michigan, Washington, Argentina, Mexico, and New Zealand were processed into juice; the 8 samples included Golden Delicious, Jonathan, Granny Smith, and Mcintosh varieties. Liquid chromatography was used for quantitation of sugars (glucose, fructose, sucrose, and sorbitol), nonvolatile acids (malic, quinic, citric, shikimic, and fumaric), and phenolics (chlorogenic acid and hydroxymethylfurfural [HMF]). Other determinations included pH, °Brix, and L-malic acid. A number of compositional indices for these authentic juices, e.g., chlorogenic acid content, total malic - L-malic difference, and the HMF: chlorogenic ratio, were at variance with recommended standards. The phenolic profile was shown to be particularly influenced by gelatin fining, with peak areas decreasing by as much as 50%. The L-malic: total malic ratio serves as a better index for presence of synthetic malic acid than does the difference between the 2 determinations. No apparent differences in chemical composition could be attributed to geographic origin.
Stable Isotopic Carbon Composition of Apples and Their Subfractions—Juice, Seeds, Sugars, and Nonvolatile Acids
Authors: Lee Hyoung S , Wrolstad Ronald E 
Published: February 2020

Abstract
The 13C:12C ratios of 8 authentic apple juice samples and their subfractions were determined by mass spectrometry. Apples from Argentina, Mexico, New Zealand, and the United States were processed into juice; pulp was collected from the milled fruit and seeds were collected from the press-cake. Sugars, nonvolatile acids, and phenolics were isolated from the juice by treatment with ion-exchange resins and polyvinylpyrrolidone (PVPP). The mean value for all juice samples was — 24.2%o which is close to the values reported by other investigators. Juice from apples grown in Argentina, Mexico, and New Zealand did not differ from U.S. samples. The isotopic composition of the subfractions ranged from -22.0 to -31.0%o. The values for the pulp were essentially the same as for juice. The sugar fraction was slightly less negative than the juice; the nonvolatile acid and phenolic fractions were more negative. The levels of nonvolatile acids and phenolics in apple juice are low, however, so these compounds contribute little to overall δ13C values in juice.
Determination of Vitamin K1 in Powdered Infant Formulas, Using Supercritical Fluid
Extraction and Liquid Chromatography with Electrochemical Detection
Authors: Schneiderman Martin A , Sharma Avadhesh K , Mahanama Kariyawasam R R , Locke David C 
Published: February 2020

Abstract
Vitamin K, (phylloquinone) is extracted from commercial soy proteinbased and milk-based powdered infant formulas by using supercritical fluid extraction with C02 at 8000 psi and 60°C. Quantitative extraction requires only 15 min, and does not suffer from the problems associated with conventional solvent extraction of lipophilic materials from media such as formulas. Vitamin K, is determined in the extracts by using reverse-phase liquid chromatography (LC) with reductive mode electrochemical detection at a silver electrode polarized at —1.1 V vs SCE. LC run time is 9 min. The minimum detectable quantity is 80 pg, and response is linear over at least 5 orders of magnitude. Recovery of vitamin K, from a milk-based powdered formula was 95.6% with RSD of 7.4%, and from a soy protein-based product, 94.4% recovery with RSD of 6.5%.
Screening Method for Determination of High Levels of Cadmium, Lead, and Copper in Foods
by Polarized Zeeman Atomic Absorption Spectrometry Using Discrete Nebulization Technique
Authors: Saito Isao , Oshima Harumi , Kawamura Norihisa , Yamada Masuo 
Published: February 2020

Abstract
A screening method for determination of cadmium, lead, and copper in foods was developed. The sample (1-3 g) is digested with HN03- H2S04-HCI04 in a centrifuge tube attached to a straight glass tube that prevents loss of HN03 by volatilization. After digestion, potassium iodide, H2S04, and MIBK (4-methyl 2-pentanone) are added, and the metals are extracted with MIBK as metal iodides. The MIBK solution is injected and the metals are determined by flame polarized Zeeman atomic absorption spectrometry using a discrete nebulization technique. Recoveries of metals from fortified milk powder, unpolished rice, fish, beef, peanut butter, apple, and cabbage were satisfactory. The analytical results for NBS Oyster Tissue and NIES Pepperbush, Chlorella, and Mussel agreed with certified or reference values except lead in Pepperbush. The limits of quantitation for cadmium, lead, and copper were 0.01, 0.09, and 0.02 ppm, respectively. This method is simple and safe for routine analysis of high levels of cadmium, lead, and copper in foods.
Automated Microanalysis for Reducing Sugars, Sucrose, and Starch in Single Soybean
Leaflets
Authors: Hoogenboom Gerrit , Huck Morris G , Peterson Curt M , Goli Ankon 
Published: February 2020

Abstract
An automated enzymatic hydrolysis procedure was developed to analyze aqueous leaf extracts for soluble carbohydrates in the presence of chlorophyll. Following an initial estimate of free reducing substances in the extracts from individual soybean {Glycine max [L.] Merr. 'Braxton') leaflets, separate portions were incubated with invertase or amyloglucosidase. The increase in ferricyanide reduction after incubation with the enzyme was assumed to represent the concentration of sucrose or starch, respectively, in the original extract. Use of an autoanalyzer operating in a double-beam mode compensated for interference from chlorophyll and other endogenous pigments. Extraction efficiency was checked by successive boiling-water extractions, and enzymatic incubation conditions were verified by a series of internal calibration standards. After 3 successive boilingwater extractions of § min each, more than 95% of the soluble sucrose was removed from the leaflets. Although the conditions of these procedures were insufficient for quantitative removal of all soluble starch present in the soybean leaflet, they represent a compromise that yields an aqueous extract which is amenable to enzymatic assay while avoiding excessive degradation of labile carbohydrates during the extraction process. This method allowed for a rapid comparison between drought-stressed and non-stressed soybean leaflets, which were collected during field experiments and stored in a laboratory freezer for later analysis of osmotic potential and soluble carbohydrates, e.g., glucose, fructose, sucrose, and starch.
Determination of Intermediates and Side-Reaction Products in Tartrazine by
Ion-Pair Liquid Chromatography
Authors: Kirchmayr Klaus , Malissa Hans , Szolgyenyi Gerald P , Winsauer Karl 
Published: February 2020

Abstract
A reverse-phase ion-pair liquid chromatographic method was applied to the measurement of uncombined intermediates and side-reaction products in Tartrazine (FD&C Yellow No. 5). These compounds, sulfanilic acid, phenylhydrazine-p-sulfonic acid, pyrazolone-T, methyl and ethyl esters of pyrazolone-T, and 4,4'-(diazoamino)-dibenzenesulfonic acid, form strong ion pairs with the tetrabutylammonium (TBA) counterion, which are separated on an RP-18 column with a methanol-water solvent mixture under acidic conditions. Baseline resolution is attained with a 0.03 mol/L TBA concentration and a pH of 2.5. With a linear step flow program and 40°C column temperature, elution time is reduced to 20 min with no equilibration between individual runs. Performance data for quantitative measurement are given in terms of calibration curve linearity (r between 0.98 and 1.00 for all compounds studied) and method detection limit (from 0.004 to 0.022% as % per weight of Tartrazine).
Reverse-Phase Liquid Chromatographic Determination of Lysine in Complete Feeds and
Premixes, Using Manual Precolumn Derivatization
Authors: Cottingham Layna S , Smallidge Robert L 
Published: February 2020

Abstract
A sample portion is hydrolyzed with 6N HCl for 23 h and cooled, the pH is adjusted to 7.7 with NaOH, and the solution is diluted with pH 7.7 borate buffer. An aliquot of the sample extract is derivatized with 9-fluorenylmethyl chloroformate (9-FMC). Lysine is separated from other amino acids by isocratic reverse-phase liquid chromatography (LC) using fluorescence detection: 260 nm excitation and 313 nm emission. The mobile phase is acetonitrile-O.lM acetic acid (pH 4.2) buffer (53 + 47). Linearity is satisfactory over a range of 0.4-24 Mg/mL. Results from 9 feed samples (1.1-2.7% lysine) analyzed by both the LC method and an amino acid analyzer were not significantly different statistically. Recovery of standard lysine, spiked just before derivatization on these same 9 samples (in duplicate), was 100.9% with a coefficient of variation (CV) of 2.4%. A study of within-day and between-day method precision resulted in CVs of 1.1 and 1.8%, respectively. The variation of results was negligible when the method was tested for ruggedness on 7 factors.