bluuebunny/crossref_metadata_2025_split huggingface dataset:
International Proficiency Testing of Analytical Laboratories for Foods and Feeds from 1990 to 1996: The Experiences of the United Kingdom Food Analysis Performance Assessment Scheme
Authors: Key Pauline E , Patey Alan L , Rowling Simon , Wilbourn Anne , Worner Fiona M 
Published: February 2020

Abstract
The Food Analysis Performance Assessment Scheme (FAPAS) organized by a Secretariat of the UK Ministry of Agriculture, Fisheries, and Food has checked the proficiency of analytical laboratories for foods and feeds from 1990 to 1996. FAPAS was started for UK laboratories but was expanded worldwide at the request of analysts in other countries who did not have a home-based scheme. Thirteen thousand homogeneity-checked test materials were issued, covering a very wide range of analytes, including pesticides, toxins, veterinary drug residues, trace and nutritional elements, food colors, preservatives, sweeteners, alcohol congeners, fatty acids, nitrate, and proximate analysis. Participants returned 85% of requested data, and 47 000 z- score proficiency assessments were made, of which 81% were satisfactory. Evidence is presented of improvements in overall analytical ability with increased participation in proficiency testing in the areas of proximate analysis; organochlorine pesticide analysis; and lead, mercury, and acesul- fame-K analyses. Little improvement was shown in other analytical areas such as calcium analysis. Overall accuracies for analysis of specific pesticides and specific trace elements in the circulated test materials were compared.
New Trends in Food Microbiology: an AOAC INTERNATIONAL Perspective
Authors: Andrews Wallace H 
Published: February 2020

Abstract
The paper discusses 5 major trends in food microbiology from an AOAC INTERNATIONAL perspective. The first trend, and perhaps the one with the greatest impact on food microbiology during the past 10 years, is the introduction of the rapid test kit. The development of these kits is a result of attempts to expedite, simplify, miniaturize, and automate methods. The second trend is the introduction of new method validation programs. AOAC INTERNATIONAL offers 2 alternatives to method validation by collaborative study: the Test Kit Performance Tested Method Program and the Peer-Verified Method Program. The third trend is the increasing use of microbiological reference materials. Applications of reference materials and of certified reference materials is addressed. The fourth trend is the evolving international character of not just AOAC INTERNATIONAL but other recognized scientific organizations as well. An attempt at method harmonization is one important consequence of this evolving internationalism. Moreover, there is a growing trend toward sharing of microbiological expertise on a global scale, reflecting our ever-shrinking geographical differences. The fifth trend is the implementation and increasing use of the Hazard Analysis Critical Control Point (HACCP) concept. The nature of the HACCP program and its influence on microbiological testing of the finished product are described.
Fructans in Foods and Food Products, Ion-Exchange Chromatographic Method: Collaborative Study
Authors: Hoebregs Hubert ,   Collaborators:, Balis P , De Vries J , Eekelen J v , Farnell P , Gray K , Goedhuys B , Hermans M , Heroff J , van Leeuwen M , Li B W , Martin D , Pieters M , Quemener B , Roomans H , Slaghek T , Thibault J-F , van der Waal W , de Wit D 
Published: February 2020

Abstract
Nine collaborating laboratories assayed 6 blind duplicate pairs of food samples containing the fructans inulin or oligofructose. The 6 sample pairs ranged from low (4%) to high levels (40%). Following the proposed method, the samples were treated with amyloglucosidase and inulinase enzymes and the released sugars were determined byion exchange chromatography. Repeatability standard deviation ranged from 2.9 to 5.8%; reproducibility standard deviation ranged from 4.7 to 11.1%. The ion-exchange chromatographic method for determinationof fructans in food and food products has been adopted first action by AOAC INTERNATIONAL (997.08)
Performance Evaluation of Direct Forced-Air Total Solids and Kjeldahl Total Nitrogen Methods: 1990 through 1995
Authors: Lynch Joanna M , Barbano David M , Healy Patrick A , Fleming J Richard 
Published: February 2020

Abstract
Results from collaborative studies of the performance of the direct forced-air oven-drying method for determination of milk total solids content (AOAC Method 990.20) and the Kjeldahl total nitrogen method for determination of milk total nitrogen content (AOAC Method 991.20) were published in 1989 and 1990, respectively. Method performance was characterized by using the harmonized ISC7IUPAC/ AOAC guidelines for method validation, and the methods now have final action status. During1990 through 1995, the split sample collaborative study format was used to monitor the performance of these methods as part of a multilaboratory quality assurance program. Seven blind duplicate milk materials were sent from a central laboratory onceevery 2 months to participating laboratories. Data were analyzed with the same statistical procedures used in the original collaborative studies. Compared with the original collaborative study, the repeatability and reproducibility of the oven-drying method improved over time. For the Kjeldahl total nitrogen method, within-laboratory repeatability improved slightly, whereas between-laboratory reproducibility was similar to but not always as good as in the original study. The results demonstrate that the statistical protocol for collaborative studies can be used effectively as the basis for a multilaboratory quality assurance program and that the method performance achieved in a collaborative study can be maintained and even improved with time.
Determination of Residues of Alachlor and Related Herbicides in Crops by Liquid Chromatography with Electrochemical Detection
Authors: Nortrup David A 
Published: February 2020

Abstract
A method is described for determining residues of 3 acetamide herbicidesalachlor [2-chloro-N(2,6- diethylphenyl)-N(methoxymethyl)acetamide], acetochlor [2-chloro-N(2-ethyl-6-methylphenyl)-N (ethoxymethyl)acetamide), and butachlor [2-chloro-N(2,6-diethylphenyl)-N(butoxymethyl)- acetamide)by liquid chromatography (LC). Currently no published method determines metabolites from all 3 herbicides in crops. Strong-base hydrolysis after extraction of a test portion with water-acetonitrile results in the formation of 2,6- diethylaniline (DEA) and 2-(1-hydroxyethyl)-6-ethylaniline from alachlor metabolites, 2-ethyl-6-methylaniline and 2-(1-hydroxyethyl)-6-methylaniline from acetochlor metabolites, and DEA from butachlor. The anilines are isolated by steam distillation, partitioned with Supelclean ENVI-Chrom P solid-phase extraction columns, and methylated prior to LC analysis. The limit of quantitation of aniline moieties is about 0.01 ppm. Recoveries of 0.01- 0.40 ppm aniline moieties are generally 74-103%, with relative standard deviations of 2.2 to 14.0%.
Liquid Chromatographic Method for Determining the Concentration of Bisazir in Water
Authors: Scholefield Ronald J , Slaght Karen S , Allen John L 
Published: February 2020

Abstract
Barrier dams, traps, and lampricides are the techniques currently used by the Great Lakes Fishery Commission to control sea lampreys {Petromyzon marinug) in the Great Lakes. To augment these control techniques, a sterile-male-release research program was initiated at the Lake Huron Biological Station. Male sea lampreys were sterilized by intraperitoneal injection of the chemical sterilant P,P-bis(1-aziridinyl)-Nmethylphosphinothioic amide (bisazir). An analytical method was needed to quantitate the concentration of bisazir in water and to routinely verify that bisazir (&gt;25 μg/L) does not persist in the treated effluent discharged from the sterilization facility to Lake Huron. A rapid, accurate, and sensitive liquid chromatographic (LC) method was developed for determining bisazir in water. Bisazir was dissolved in Lake Huron water; extracted and concentrated on a C18 solid-phase extraction column; eluted with methanol; and quantitated by reversed-phase LC using a Cis column, amobile phase of 70% water and 30% methanol (v/v), and UV detection (205 nm). Bisazir retention time was 7-8 min; total run time was about 20 min. Method detection limit for bisazir dissolved in Lake Huron water was about 15 μg/L. Recovery from Lake Huron water fortified with bisazir at 100 μg/L was 94% (95% confidence interval, 90.2-98.2%).
Comparative Study of Colorimetric and Fully Automated Enzyme-Linked Immunoassay System for Rapid Screening of Listeria spp. in Foods
Authors: Kerdahi Khalil F , Istafanos Philip F 
Published: February 2020

Abstract
Two enzyme-linked immunoassay (ELISA) systems for rapid screening of Listeria spp. were compared for their use in analysis of spiked foods regulated by the U.S. Food and Drug Administration. The Tecra Listeria kit is a 48 h visual ELISA that detects Listeria spp. through colorimetry. It has been approved for first action by AOAC INTERNATIONAL.The Vitek immunodiagnostic assay system for Listeria (\i\D AS LIS) is a fully automated 48 h ELISA that detects Listeria spp. by immunofluorescence. Fifty-two food samples were artificially contaminated with high (11-42 colony-forming units [cfu]/25 g food) and low (2-8 cfu/25 g food) levels of L monocytogenes and screened by the 2 protocols. Unspiked samples were also assayed as negative controls. Six unspiked samples werefound positive for Listeria spp. by both methods: 3 were identified as L. monocytogenes and 3 as L. innocua by official methods. Both ELISA methods detectedall spiked samples. One unspiked sample was assayed positive by Tecra and negative by VIDAS LIS. No Listeria spp. were recovered when the sample was tested by the conventional method. Nointerference due to background fluorescence of food matrixes was observed in the VIDAS LIS method. Results suggest a modified VIDAS LIS preenrichment medium may be used in place of the VIDAS standard medium in the protocol.
Stability of Sulfonamide Antibiotics in Spiked Pig Liver Tissue During Frozen Storage
Authors: Thomas George K , Millar Roderick G , Anstis Peter W 
Published: February 2020

Abstract
A bulk portion of homogenized pig liver tissue was spiked at room temperature with 0.2 mg/kg (twice the Australian maximum residue limit) of each of sulfathiazole, sulfachlorpyridazine, sulfadimidine (sulfamethazine), sulfaquinoxaline, and sulfadimethoxine. After subsampling and packaging, selected individual packaged units were tested to confirm homogeneity of the prepared material. The material was stored frozen at -20°C and analyzed in replicate by liquid chromatography on 11 sampling dates over a period of about 6 months. Analytical data were plotted on a log-linear scale and subjected to linear regression on the basis of firstorder kinetics for the decay. Storage stabilities (decay half-lives at -20°C) calculated from the mean slope of regression lines were sulfadimethoxine, 567 days; sulfadimidine, 457 days; sulfachlorpyridazine, 312 days; sulfathiazole, 291 days; and sulfaquinoxaline, 271 days. Significant depletion (65% loss) of residue was observed for sulfaquinoxaline during preparation of spiked bulk liver tissue. An extension of the study to measure the storage stability of sulfaquinoxaline under accelerated decay conditions (refrigerator temperature, 4°C) showed it to be relatively unstable, with a decay half-life of 11 days. Results demonstrate the need for both regulatory agencies and testing laboratories to be aware of potential errors associated with improper transport, storage, and handling of tissue samples submitted for antibiotic testing.
Determination of Tilmicosin in Bovine and Porcine Sera by Liquid Chromatography
Authors: Moran John W , Turner James M , Coleman Mark R 
Published: February 2020

Abstract
A liquid chromatographic (LC) assay is described for determining tilmicosin in bovine and porcine blood sera. Tilmicosin is isolated from the serum matrix and purified by solid-phase extraction with C18 sorbent. Sample is analyzed by LC using a gradient system with a phenyl reversed-phase column that separates tilmicosin from the matrix in 30 min. Tilmicosin is measured by UV absorbance at 280 nm. Validation of assay included evaluation of accuracy, precision, linearity, specificity, sensitivity, range, and sample stability. The method has a limit of quantitation of 0.1 ppm and a validated range of 0.1 to 10.0 ppm. Recoveries were 91–95% for bovine serum and 85–93% porcine serum. The limit of detection was 0.05 (μg/mL. Limits of detection and quantitation were based on 3 and 6 times the baseline noise of control serum samples, respectively. Relative standard deviations of precision samples (n = 6) were 2% or less for both sera. The method has better specificity and analysis time than previous microbiological methods for tilmicosin in sera.
Survival and Detection of Shigella flexneri in Vegetables and Commercially Prepared Salads
Authors: Rafii Fatemeh , Lunsford Pamala 
Published: February 2020

Abstract
The normal bacterial microflora of 4 commercially prepared salads (coleslaw, crab salad, carrot salad, and potato salad) and 3 vegetables (green pepper, onion, and cabbage) were evaluated. Twenty-eight species of bacteria, including potential pathogens, were isolated. The foods were artificially inoculated with an avirulent mutant strain of Shigella flexneri 5 (pHS1059) to develop a method for the rapid detection of Shigella spp. Bacteria were separated from insoluble and particulate salad ingredients by filtration through shark skin filter paper and by low speed centrifugation. S. flexneri survived at 4°C in all salads for at least 11 days and up to 20 days in crab salad. The polymerase chain reaction (PCR), using primers for amplification of a 118-base pair DNA fragment from the virulence-associated spa region, present in all Shigella spp., was used to detect S. flexneri in filtrates from salads inoculated with S. flexneri 5 (pHS1059). DNA was amplified from all of the artificially contaminated salads and vegetables except green pepper. After 3–5 days of storage, the PCR also amplified S. flexneri DNA from salads that had been enriched with nutrients to increase the number of bacteria. Green peppers contained a PCR inhibitory substance that was attenuated by dilution and enrichment before the PCR. No amplification of DNA was observed in foods to which S. flexneri had not been added.
Effects of Salt and Serum on the Sporicidal Activity of Liquid Disinfectants
Authors: Sagripanti Jose-Luis , Bonifacino Aylin 
Published: February 2020

Abstract
This study compares the effects of various concentrations of salt or serum in the killing of Bacillus subtilis spores by either glutaraldehyde, sodium hypochlorite, cupric ascorbate, hydrogen peroxide, peracetic acid, formaldehyde, or phenol. Salt affected only glutaraldehyde, its sporicidal activity increasing with an increase in concentration of sodium bicarbonate or sodium chloride. The sporicidal activity of glutaraldehyde was minimal when the concentrations of aldehyde groups and lysine residues from protein were similar. We present an equation describing the effect of serum on spore survival as a function of glutaraldehyde concentration that fits the data with a regression coefficient of 0.9. Cupric ascorbate and peracetic acid were inhibited by serum, but this effect was linked to a rise in pH. Sodium hypochlorite was the agent most sensitive to protein, with its sporicidal activity nearly disappearing in the presence of 2% serum or an equivalent amount of purified protein.
Supercritical Fluid Extraction of Polychlorinated Biphenyls and Organochlorine Pesticides from Freeze-Dried Tissue of Marine Mussel, Mytilus eduli
Authors: Yoo Wesley J , Taylor Larry T 
Published: February 2020

Abstract
Supercritical fluid extractions (SFEs) of 21 polychlorinated biphenyls (PCBs) and 8 organochlorine pesticides (OCPs) from freeze-dried mussel tissue are compared with traditional Soxhlet extractions. The aim was to determine the efficacy of supercritical CO2 to extract these 2 classes of lipophilic compounds. A spike study to determine the feasibility of on-line cleanup by inclusion of an inert matrix (activated alumina) in the extraction vessel showed that the chemical integrity of the PCBs was not compromised, whereas some DDTs were decomposed to their respective metabolites. Relatively long static extraction time, higher density, and lower temperature yielded quantitative recoveries of PCBs from freeze-dried mussel tissue with good reproducibilities. Recoveries of OCPs were nonquantitative and highly variable. Finally, the efficacy of fluoroform (CHF3) as an alternative supercritical fluid to selectively extract PCBs and OCPs was studied. Fluoroform yielded nonquantitative and variable recoveries of PCBs and OCPs, but its use eliminated the need for in situ alumina to retain coextracted lipids from the matrix.
A Bridging Study Between Liquid Chromatography and Microbial Inhibition Assay Methods for Determining Amoxicillin Residues in Catfish Muscle
Authors: Ang Catharina Y W , Luo Wenhong , KiessLing Connie R , Mckim Karen , Lochmann Rebecca , Walker Calvin C , Thompson Harold C 
Published: February 2020

Abstract
A bridging study was conducted to establish the correlation between a liquid chromatographic (LC) method and a microbial inhibition (Ml) method for analysis of amoxicillin residues in catfish muscle. The LC procedure involved precolumn derivatization with formaldehyde followed by LC separation with fluorescence detection. The Ml procedure used Bacillus stearothermophilus as the test organism and was validated in this study before the bridging investigation. The 2 methods were compared for determination of both fortified and incurred samples. No significant differences were found between the methods when all data were included in statistical computations. The linear correlation of LC means versus Ml means had a slope of 0.972 and a negligible intercept (1.0 ng/g), with a correlation coefficient of 0.9962. LC was more specific and showed better sensitivity than Ml for amoxicillin residues at ≤10 ng/g. For practical purposes, values obtained by the 2 methods can be considered equivalent.
X-Ray Fluorescence Determination of Manganese in FD&C Blue No. 1
Authors: Hepp Nancy M 
Published: February 2020

Abstract
An X-ray fluorescence (XRF) method was developed for determining manganese in FD&C Blue No. 1 from simply prepared pressed pellets. Results were compared with those of atomic absorption spectroscopy (AAS) of acid-digested or ashed samples. Levels of manganese determined by XRF and AAS were equivalent. The limit of detection (3σ) for the XRF method was 3µg manganese/g dye. The 95% confidence interval at the specification level was 100 ± 10 μg manganese/g dye
Direct 24-Hour Presumptive Enumeration of Escherichia coli 0157:H7 in Foods Using Hydrophobic Grid Membrane Filter Followed by Serological Confirmation: Collaborative Study
Authors: Entis Phyllis ,   Collaborators:, Bryant D , Bryant J , Bryant R G , Inami G , Cholensky J S , Garcia G R , Ramsey S M , Courtney T , Pruett W P , Dagdag E B , Davis-DeBella P E , San Diego , Humes L M , Lau D , Watson J , Erickson J , Hayes M , Ingham S , Sage J , Jirele K , Zuroski K , Kelley G , Lerner I , Patel D R , Peery D A , Simpso S , Zachary C 
Published: February 2020

abstract
Fifteen laboratories took part in a collaborative study to validate a method for enumerating Escherichia coli 0157:H7. The method is based on use of a hydrophobic grid membrane filter and consists of 24 h presumptive enumeration on SD-39 Agar and serological confirmation to yield a confirmed E. coli 0157:H7 count. Six food products were analyzed: pasteurized apple cider, pasteurized 2% milk, cottage cheese, cooked ground pork, raw ground beef, and frozen whole egg. The test method produced significantly higher confirmed count results than did the reference method for milk, pork, and beef. Test method results were numerically higher than but statistically equivalent to reference method results for cheese, cider, and egg. The test method produced lower repeatability and reproducibility values than did the reference method for most food/inoculation level combinations and values very similar to those of the reference method for the remaining combinations. Overall, 94% of presumptive positive isolates from the test method were confirmed serologically as E. coli 0157:H7, and 98% of these were also biochemically typical of E. coli 0157:H7 (completed test). Corresponding rates for the reference method were 69 and 98%, respectively. On the basis of the results of this collaborative study and the precollaborative study that preceded it, it is recommended that this method be adopted official first action for enumeration of E. coli 0157:H7 in meats, poultry, dairy foods, infant formula, liquid eggs, mayonnaise, and apple cider
Stability of Organic Pollutants During Microwave-Assisted Extraction from Solid Matrixes
Authors: Lopez-Avila Viorica , Young Richard , Beckert Werner F 
Published: February 2020

abstract
A stability study was conducted for 95 semivolatile organics listed in U.S. Environmental Protection Agency Method 8250 (this number includes 6 surrogate compounds). These compounds were spiked into solvent only [hexane-acetone (1 +1), methylene chloride-acetone (1 +1), toluenemethanol (10 + 1), and methyl ferf-butyl ether], solvent/dry soil suspensions, and solvent/wet soil suspensions [20% water (w/w)] and heated with microwave energy in closed vessels at 50° or 145° C for 5 or 20 min. For comparison and to determine nitrogen blowdown losses, spiked solvent samples that had not been exposed to microwave energy were concentrated by the blowdown technique and analyzed for each of the spiked compounds. Hexane-acetone (1+1) seems to be the best for the compounds and matrixes investigated, with recoveries &gt; 80%, except for basic compounds and benzoic acid in the solvent/dry soil suspension experiments. Increasing extraction time from 5 to 20 min did not increase recoveries; in fact, recoveries of neutral compounds decreased slightly at the longer extraction time. Increasing the temperature from 50° to 145° C decreased recoveries of basic compounds by about 10%. Recoveries of basic compounds, of benzoic acid (and probably other organic acids as well), and at least to some extent of phenolic compounds from the solvent/wet soil suspensions were higher than those for solvent/dry soil suspensions.
Solid-Phase Extraction Cleanup for Ivermectin in Liver Tissue
Authors: Reising Kyle P , Benedetto Nrffer Migdal Di 
Published: February 2020

abstract
Extraction of liver tissue with organic solvent produces coextractants with compounds of interest. The solid-phase extraction (SPE) cleanup of liver tissue developed for ivermectin removes nonpolar coextractants. Liver extract that has been reduced to dryness is reconstituted in 0.5 mL acetonitrile. The mixture is passed through 0.1 g C18 SPE column, and the eluate is collected. The column is eluted further with 2 mL acetonitrile. Combined eluates are derivatized with 1-methylimidazole and trifluoroacetic anhydride, and the ivermectin derivative is determined by liquid chromatography with fluorescence detection.
Occurrence of β2- Adrenergic Agonist Residues in Urine of Animal Meat Producers in Portugal
Authors: Ramos Fernando , Castilho M Conceicāo , Da Silveira M Irene Noronha 
Published: February 2020

abstract
Between January 1,1991, and December 31,1993, bovine urine was collected for analysis of β2-adrenergic agonist residues. A multiresidue method was developed that was capable of detecting clenbuterol, clenpenterol, clenproperol, mabuterol, mapenterol, bromobuterol, tulobuterol, and salbutamol through enzyme-linked immunosorbent assay, liquid chromatography (LC) with photodiode array detection, and gas chromatography with mass detection in electron impact mode with selective-ion monitoring. Among 1031 samples, 24 contained clenbuterol and 1 contained salbutamol. The results confirm that clenbuterol is the β2-adrenergic agonist most used as bovine growth promoter in Portugal.