bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination Of Total Sulfite In Shrimp, Potatoes, Dried Pineapple, And White Wine By Flow Injection Analysis: Collaborative Study
Authors: Sullivan John J , Hollingworth Thomas A , Wekell Marleen M , Meo Victor A , Saba Haytham H , Etemad-Moghadam Ali , Eklund Cheryl , Phillips John G , Gump Barry H 
Published: February 2020

Abstract
A method for the determination of total sulfite in shrimp, potatoes, dried pineapple, and white wine by flow injection analysis (FIA) was collaboratively studied by 8 laboratories. In the method, the sample solution Is reacted with sodium hydroxide to liberate aldehyde-bound sulfite. The sample stream is acidified to produce S02 gas, which diffuses across a Teflon membrane in the gas diffusion cell into a flowing stream of malachite green. The degree of discoloration of the malachite green is proportional to the amount of sulfite in the sample solution. Red wine was included in the study but Interlaboratory precision for these samples was not satisfactory and correlation with Monier-Williams results was poor. The present method is not recommended for use with these samples. For shrimp, potatoes, dried pineapple, and white wine, average reproducibility (RSDR) of results was 25% for samples at 10 ppm S02 and 10% for samples at &gt;50 ppm. Overall average reproducibility was 14%. Recoveries of sulfite added to samples averaged 80%. Comparison of FIA with the Monier-Williams method indicated comparable results by the 2 methods. The FIA method has been adopted official first action for determination of ≥5 ppm total sulfite in shrimp, potatoes, dried pineapple, and white wine.
Comparison of Three Liquid Chromatographic Methods with FDA Optimized Monier- Williams Method for Determination of Total Sulfite in Foods
Authors: Lawrence James F , Chadha Rajinder K , Menard Cathie 
Published: February 2020

Abstract
Three liquid chromatographic (LC) methods employing amperometric detection were compared with the collaboratively studied FDA optimized Monier-Williams distillation method for the determination of total sulfite in 5 food types. The foods included lemon juice, white wine, instant mashed potatoes, golden raisins, and onion flakes. Two of the LC methods (one employing headspace sampling and the other direct injection) used ion-exchange chromatography with a basic mobile phase (pH about 10.8) and a glassy carbon electrode; the third (employing direct injection) used ion-exclusion chromatography with an acidic mobile phase (pH about 2) and a platinum electrode. All 4 methods produced similar results for the wine, lemon juice, and raisins. Results were different for instant mashed potatoes and onion flakes. The headspace- LC method and direct ion-exclusion LC method, both of which employed an alkaline sample extraction, yielded significantly higher values for sulfite in instant potatoes than did the other 2 methods. A large interfering peak with both direct LC methods prevented quantitation of sulfite in the onion flakes. All methods can detect sulfite as low as about 1 jtg/g in 4 of 5 food types examined.
Factors Influencing Optimization of Diffusion Assays for Antibiotics
Authors: Brady Marietta Sue , Katz Stanley E 
Published: February 2020

Abstract
Agar nutrient content, cylinder charge volume, thickness (volume) of the agar layer, and incubation temperature were 4 factors varied to determine their effect(s) on the optimization of the cylinder-plate diffusion assay. Chlortetracycline was the pilot antibiotic and Bacillus cereus was used as the assay organism. Zones of inhibition were larger when the incubation temperature was lower than that which was commonly used and/or when the nutrient level was decreased; the zones were smaller when the incubation temperature was raised and/or when an increased nutrient level was used. The thickness (volume) of the assay layer played the most important role; the thinner the layer the less the effect the cylinder charge volume had on the zone diameter. The slopes of the response lines were minimally affected by cylinder charge volume. For a 7 mL assay layer per standard Petri plate, cylinder charge volumes ranging from 150 to 250 μL had little effect on zone diameter. The linearity of the response line was unaffected by assay layer thickness (volume), nutrient level, temperature of Incubation, or cylinder charge volume. As long as the conditions for the assay were standardized, there were no discernible effects on recoveries or potencies.
Outgrowth of Naturally Occurring Clostridium botulinum in Vacuum-Packaged Fresh Fish
Authors: Lilly Timothy , Kautter Donald A 
Published: February 2020

Abstract
A total of 1074 test samples of commercial, domestic, vacuum- packaged fresh fish were studied to determine whether spoilage occurs before the products become toxic from naturally occurring Clostridium botulinum spores. The products were incubated for 12 days at 12°C (mild abuse). After incubation, they were tested for botulinal toxin and evaluated for organoleptic acceptability. Even when only marginally acceptable to laboratory personnel, none of the 1074 test samples were positive for C. botulinum toxin. Thus, the fish either contained no C. botulinum spores, or the spores were unable to grow out and produce toxin before spoilage made the product marginally unacceptable.
Determination of Ten N-Nitrosoamino Acids in Cured Meat Products
Authors: Pensabene John W , Fiddler Walter 
Published: February 2020

Abstract
A rapid, sensitive, and accurate solid-phase extraction method was developed for the measurement of 10 N-nitrosoamino acids (NAAs) in cured meat products. In the procedure, the comminuted meat was mixed with sulfamic acid and Celite, and then added to a glass column containing anhydrous sodium sulfate. The column was washed with pentane, and the NAAs were eluted with ethyl acetate. The eluate was concentrated, then derivatized with diazomethane followed by acetic anhydride-pyridine reagent. The NAA methyl esters and their acylated hydroxy derivatives were separated by gas chromatography on a DB-5 fused silica capillary column and quantitated with a thermal energy analyzer, a chemiluminescence detector specific for nitric oxide derived from the thermal denitrosation of nitrosamines. Recovery of 10 of the NAAs exceeded 75% at the 10 ppb level. The method is applicable to a wide range of cured meat products.
Dry Rehydratable Film for Enumeration of Total Aerobic Bacteria in Foods: Collaborative Study
Authors: Curiale Michael S , Sons Therese , Mcallister J Sue , Halsey Barbara , Fox Terrance L 
Published: February 2020

Abstract
A rehydratable dry-film plating procedure for aerobic plate counts has been compared to the standard agar plate method (966.23B and C, 15th ed.; 46.014-46.015, 14th ed.) in a collaborative study by 12 laboratories. Each laboratory analyzed the normal microflora of 3 samples in duplicate for 6 products. The aerobic plate counts ranged from 1.0 X 103 to 1.0 X 108 cfu/g. The products were flour, nuts, frozen raw shrimp, spice, frozen raw ground turkey, and frozen and refrigerated vegetables. Repeatability standard deviations of the 2 methods did not differ significantly for 13 of 18 test samples. For 1 shrimp and 2 turkey samples, the dry-film method had lower repeatability variances (P &lt; 0.05) and for 1 spice sample the agar method had lower repeatability variances (P &lt; 0.05). Relative standard deviations of repeatability were between 1.7 and 15.5% for the dry-film method and 1.2 and 16.0% for the agar method. Relative standard deviations of reproducibility ranged from 2.4 to 23.4 % for the dry-film method and 2.3 to 18.8% for the agar method. The dry rehydratable film method has been adopted official first action for determination of the aerobic plate count.
Improved Spectrophotometric Determination of Cyclopiazonic Acid in Poultry Feed and Corn
Authors: Chang-Yen Ivan , Bidasee Keshore 
Published: February 2020

Abstract
An improved visible spectrophotometric method has been developed for cyclopiazonic acid in poultry feed and corn. The method Is based on the reaction of cyclopiazonic acid with Ehrlich reagent and detection at 580 nm. Reaction conditions were optimized with respect to reaction and measurement times and acid and Ehrlich reagent concentrations. Calibration curves were linear from 1 to 20 μg cyclopiazonic acid in 3 mL Ehrlich reagent, with a lower detection limit of 0.08 mg/kg for 50 g samples of poultry feed and corn. Recoveries from 50 g samples of poultry feed spiked with cyclopiazonic ranging from 0.16 to 1.20 mg/kg averaged 93.8%. Moldy corn and poultry feed samples analyzed by this method contained between 1 and 4 mg/kg cyclopiazonic acid.
Rapid Screening Method for Deoxynivalenol in Agricultural Commodities by Fluorescent Minicolumn
Authors: Gordon William C , Gordon Linda J 
Published: February 2020

Abstract
A rapid screening procedure based on the selective adsorption of deoxynivalenol (DON) from extracts of wheat and corn has been developed. DON is extracted from the sample with acetonitrile-water (85 + 15) and partially purified on a preparative minicolumn. Solvent is evaporated and the residue is dissolved in toluene-acetone (95 + 5) and chromatographed on a novel detector minicolumn which selectively adsorbs DON. A blue fluorescence is produced when the column is heated 5 min at 100°C. The procedure is capable of detecting DON at ≥ 500 ng/g. Forty-three wheat samples, contaminated with DON at 60-6300 ng/g, were assayed by gas chromatography-mass spectroscopy (GC-MS) of the heptafluorobutyryl derivative of DON and by the selective adsorption procedure. Comparison of results showed 9 1% agreement between data from the 2 methods. Selective adsorption assays were positive for all samples that were ≥ 500 ng/g by GC-MS (no false negatives) and were negative for 85 % of samples &lt; 500 ng/g (4/27 false positives). These four samples contained &gt; 200 ng/g by GC-MS. Samples of wheat (64), corn (23), soybeans (8), and sorghum (6) were extracted and extracts were assayed by thin-layer chromatography and the selective adsorption procedure. Selective adsorption assays agreed with TLC results.
Gas Chromatographic-Electron Capture Detection Method for Determination of 29 Organochlorine Pesticides in Finished Drinking Water: Collaborative Study
Authors: Lopez-Avila Viorica , Wesselman Raymond , Edgell Kenneth 
Published: February 2020

Abstract
A joint U.S. Environmental Protection Agency/AOAC interlaboratory method validation study was conducted on EPA Method 508, Determination of Chlorinated Pesticides in Water by Gas Chromatography with an Electron Capture Detector, to determine the mean recovery and precision for analyses of 29 pesticides in reagent water and finished drinking water. The study design was based on Youden's nonreplicate plan for collaborative tests of analytical methods. The waters were spiked with 29 pesticides at 6 concentration levels, as 3 Youden pairs. Eleven volunteer laboratories extracted the spiked test waters with methylene chloride, performed a solvent exchange with methyl ferf-butyl ether, and analyzed an aliquot of each extract by gas chromatography with electron capture detection. Results were analyzed using an EPA computer program, Interlaboratory Method Validation Study (IMVS), which measured recovery and precision for each of the 29 pesticides and compared the performance of the method between water types. Method 508 was judged acceptable for all analytes tested. Only 3 analytes (α-chlordane, 4,4′-DDE, and methoxychlor) exhibited practical significant matrix effects. The method has been adopted official first action.
Relative Retention Time Diagram as a Useful Tool for Gas Chromatographic Analysis and Electron-Capture Detection of Pesticides
Authors: Omura Masami , Hashimoto Kumiko , Ohta Kunio , Iio Tomoyuki , Ueda Shigekazu , Ando Keiko , Hiraide Hikaru , Kinae Naohide 
Published: February 2020

Abstract
To establish efficient operating conditions for gas chromatographic (GC) analysis of pesticides that are detected by electron-capture detector (ECD), separation degrees of 40 pesticides and their relative retention times (RRT) vs aldrin were determined. Eleven liquid phases, categorized according to the McReynolds constant (MC), were used: OV-1, OV- 3, DC-550, and OV-17 as non- or low polar liquid phases (MC ≦ 1000), OV-22, QF-1, and XE-60 as medium polar liquid phases (1000 &lt; MC ≦ 2000), PEG-20M, DEGA, and DEGS as high polar liquid phases (2000 &lt; MC), and a mixture of DC-200 and EPON1009. An RRT diagram was prepared by plotting the RRT of each pesticide on the horizontal axis and the MC values on the vertical axis. The RRT diagram could be used to describe the properties of pesticides—their behavior on each liquid phase and the precise operational conditions for qualitative GC analysis. The non- or low polar liquid phases were best suited for GC analysis of organochlorine pesticides having low polarity. Their detection limits ranged from 0.01 to 1.0 ng.
Near Infrared Reflectance Spectroscopy. I. Calibration Techniques for Forage Quality Assessment
Authors: Barton Franklin E , Burton G W , Monson W G 
Published: February 2020

Abstract
It is very time consuming and resource costly to rank forages by wet laboratory methods; therefore, near infrared reflectance spectroscopy (NIRS) was used to evaluate hybrid bermudagrass (Cynodon dactylon (L.) Pers.) cultivars for improvements In quality. Quality was assessed by the determination of acid detergent fiber (AOF), crude protein (CP), dry matter (DM), and in vitro dry matter digestibility (iVDMD). The samples were taken from plant breeding trials from 1983,1984,1985, and 1986. They included 32 cultivars, 4 cuttings, and 5 replications each for a total of 640 possible observations per year. This paper describes the process by which the NIR spectrometer was calibrated for each constituent and the effect of various methods of calibration on the performance of the NIRS system to determine quality in bermudagrass hybrids. Excellent one-year equations were obtained from calibrations using the bermudagrass parents in the 1983 samples (R2 = 0.83, 0.97, 0.70; SEC = 0.94, 0.76, 3.64, for ADF, CP, and IVDMD, respectively). Attempts to use outside populations did not produce equivalent results for the first year. The 1983 equations did not fit the 1984 and 1985 samples because of changes that were made to the spectrometer and the yearly differences in the samples. The instrument was then recalibrated with a diverse set of legumes and grass hay samples that contained some bermudagrass. These open population calibrations adequately ranked the bermudagrass entries. We documented that bermudagrass genotypes can be quickly and precisely ranked for forage quality traits via use of open population NIRS calibration equation.
Hypoglycin A Content in the Aril, Seeds, and Husks of Ackee Fruit at Various Stages of Ripeness
Authors: Chase G William , Landen William O , Soliman Abdel-Gawad M 
Published: February 2020

Abstract
Recently, hypoglycin A (HG-A), a natural toxin, was detected in canned ackee fruit. To determine the source of contamination, the HG-A content in the ackee fruit components (aril, seeds, and husks) at various stages of ripeness was determined by a method using an amino acid analyzer. HG-A concentrations in the unripe ackee fruit components were 939, 711, and 41.6 mg/100 g of seed, aril, and husk components, respectively. Analysis of the ripe fruit components showed that HG-A in the seed decreased to 269 mg/100 g and remained unchanged in the husk while the concentrations in the edible ripe aril decreased below the detection limit of 1.2 mg/100 g.
Mass Spectrometric Confirmation of the Presence of N-Nitrosopyrrolidine in Instant Coffee
Authors: Sen Nrisinha P , Seaman Stephen W , Weber D 
Published: February 2020

Abstract
Traces of N-nitrosopyrrolidine (NPYR) may occur in some samples of both instant coffee and fine-ground roasted coffee. The identity of NPYR in 2 samples of instant coffee was confirmed by mass spectrometry as well as by liquid chromatography- thermal energy analysis. A 2-step cleanup procedure, involving fractionation on basic alumina followed by gradient elution on reverse-phase C18 cartridge, is described that allows full-scan mass spectrometric confirmation of NPYR in tested samples.
Evaluation Of Protein Digestibility-Corrected Amino Acid Score Method For Assessing Protein Quality Of Foods
Authors: arwar Ghulam , Mcdonough Frank E 
Published: February 2020

Abstract
The current concepts of protein quality evaluation were reviewed. A detailed examination of existing animal assays and more promising amino acid scoring methods has been carried out by an Ad Hoc Working Group on Protein Quality Measurement for the Codex Committee on Vegetable Proteins during the last 5 years. Several factors such as Inadequacies of protein efficiency ratio (PER, the poorest test) and other animal assays, advancements made In standardizing methods for amino acid analysis and protein digestibility, availability of data on digestibility of protein and Individual amino acids in a variety of foods, and reliability of human amino acid requirements and scoring patterns were evaluated. On the basis of this evaluation, amino acid score, corrected for true digestibility of protein, was recommended to be the most suitable routine method for predicting protein quality of foods for humans. Amino acid scores corrected for true digestibility of protein (as determined by rat balance method) were termed "protein digestibility-corrected amino acid scores." A detailed method for the determination of the protein digestibility-corrected amino acid score was proposed, and information about the range of scores to be expected In foods or food products was provided In the present Investigation. The protein digestibility-corrected amino acid score method Is a simple and scientifically sound approach for routine evaluation of protein quality of foods. Accuracy of the method would, however, be confirmed after validation with growth or metabolic balance studies In humans.
Determination of Thiabendazole, 5-Hydroxythiabendazole, Fenbendazole, and Oxfendazole in Milk
Authors: Tai Susan S.-C , Cargile Nancy , Barnes Charlie J 
Published: February 2020

Abstract
The liquid chromatographic determination previously developed for benzlmldazoles in cattle liver has been slightly modified and applied to the determination of 4 benzlmldazoles In milk. Recoveries of fenbendazole (FBZ), oxfendazole (OFZ), and thiabendazole (TBZ) from milk fortified at the 10 ppb level were 80% or greater with an Intralaboratory coefficient of variation of 11 % or less. Recovery of 5-hydroxythiabendazole (5-OH-TBZ) at the 30 ppb level averaged 56% with an Intralaboratory coefficient of variation of 5%. Limited data on the depletion of FBZ, OFZ, TBZ, and 5-OHTBZ In milk were also generated.
Liquid Chromatography and Fluorescence Detection of Vitamin A in Animal Feeds, Finished Feeds, and Premixes
Authors: Thorpe Virginia A 
Published: February 2020

Abstract
A simple liquid chromatographic method for vitamin A (retinol) in animal feeds is described. The feed is saponified, diluted to minimize interferences, and extracted Into petroleum ether with a single step. The analysis is sensitive and specific with liquid chromatography and a fluorescence detector. The minimum level of detection is 15 ng/mL, which Is equivalent to 10 000 units/lb vitamin A. The method Includes a stable and reproducible standardization of vitamin A that Is used to calibrate standard peak heights In terms of units retlnol/mL. Guarantees of 10 000 units/lb up to premix levels can be analyzed with good recoveries and precision.
Liquid Chromatographic Determination of Pindolol and Related Compounds in Raw Materials
Authors: Lacroix P M , Moir D , Lovering E G 
Published: February 2020

Abstract
A liquid chromatographic method for the assay of pindolol and related compounds In the bulk drug has been developed. The method resolves 6 known and several unknown impurities from the drug and each other by using a nitrile column, an acetonitrlle-sodlum acetate buffer (35 + 65), and a UV detector set at 219 nm. Minimum quantifiable amounts of Impurities are 0.02% or less relative to the drug. Ten lots of pindolol raw material were evaluated for purity and drug content. Total levels of Impurities In these samples, quantltated against pindolol, ranged from about 0.03 to 0.24%. Assay results were within the range of 98.5 to 101.5%.
High-Performance Immunoaffinity Chromatography for Drug Residue Analysis
Authors: Katz Stanley E , Brady Marietta Sue 
Published: February 2020

Abstract
High-performance Immunoaffinity chromatography (IAC) is a potentially strong analytical tool for measurement of drug residues In various matrixes. Although the use of Immunoaffinity separations Is not new, the application to drug residue analysis Is in its Infancy. The present paper discusses the production and purification of antibody, the preparation of columns, the theoretical basis of the analytical separation and elutlon, and variations of the analytical approach.
Diagnostic Data Evaluation. Part VI. Data Evaluation to Establish Product Standards
Authors: Malanoski Anthony J 
Published: February 2020

Abstract
Cooked corned beef was studied to evaluate the feasibility of monitoring the product by means of chemical analysis. The protein fat-free value and the molsture.-protein ratio were evaluated with respect to variability. The molsture:proteln ratio was not as effective as the former because of the greater variability and the requirement for additional analyses.
Flour Acidity Comparisons as Related to Fat Acidity Methods of the Association of Official Analytical Chemists and the International Organization for Standardization
Authors: Parker Gregory D , Lane Ralph H 
Published: February 2020

Abstract
Acidity data were compared of selected flour samples obtained by methods of the International Organization for Standardization (ISO) and the Association of Official Analytical Chemists (AOAC) with and without toluene as a part of the titration medium. In all cases, the ISO method produced significantly higher fat acidity values (P &lt; 0.001) than the AOAC method, probably as a result of greater extraction of acidic materials with the more polar solvent, 95% alcohol, than with petroleum ether. Except for a whole wheat flour sample, no differences (P &gt; 0.05) existed between fat acidity values produced by AOAC methodology consisting of titration of the evaporated petroleum ether extract of the flour in a medium of equal volumes of 95% alcohol and toluene as prescribed In the official method (14.069-14.071), or In a medium of 95% alcohol alone. Based on the data and the potential toxicity of toluene, a collaborative study Is recommended to determine the Influence of Its removal from the official AOAC method. Fat