bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison Between Liquid and Paste Karl Fischer Extractions for NIRS Water Calibrations
Authors: Windham William R 
Published: February 2020

Abstract
The acceptance of near infrared reflectance spectroscopy (NIRS) for the routine analysis of water in forage was made possible by the application of Karl Fischer (KF) water analysis as the primary reference method during calibration. Water is extracted by ball milling the sample in the presence of methanol (1:50), and an aliquot of the liquid phase is sampled and titrated. An alternative extraction utilizes a 20 g sample with 20 mL methanol, and an aliquot of the paste is sampled and titrated. The objectives of this study were to compare extraction procedures (i.e., liquid vs paste) on the determination of water in 75 milled grains and concentrate rations, and to develop and compare NIRS calibrations for water on the basis of both extraction methods. The majority of the samples (N = 61) had a 1.05 percentage unit greater water content (P &lt; 0.05) from the paste method than from the liquid method. Bias between the extraction procedures was positively correlated (r2 = 0.84) to starch content. The lowered extraction efficiency of the liquid method is explained by its inability to account for water bound to starch. NIRS calibration and equation validation statistics were superior with water data from the paste method. The increased calibration errors with the liquid method also appear to reflect the inability of the method to accurately measure the total water concentration of the samples in relation to the water measurement based on the NIRS signals. The study concludes that the KF paste method is a superior primary reference method for the determination of water in flour obtained from cereal grains and concentrate rations.
Rapid Headspace Gas Chromatographic Method for Assessment of Oxidative Stability of Cooked Chicken Meat
Authors: Ang Catharina Y W , Young Louis L 
Published: February 2020

Abstract
Experiments were conducted to determine the volatile compounds in cooked chicken meat using a static headspace gas chromatographic (GC) technique. Preheating conditions for samples in vials were tested at 70,80, and 90°C for 20-120 min at each temperature. The majority of the peaks increased in size as the temperature and time increased. Optimum conditions were established as preheating at 80°C for 30 min followed by analysis on a packed column of 8% Poly MPE on Tenax GC with the temperature programmed from 50 to 200°C at 10°/min. Coefficients of variation for major peaks ranged from 8.3 to 14.7%. These results were compared with those obtained with a capillary column analysis of samples preheated at the same conditions. Cooked and stored chicken patties, pretreated with different levels of sodium tripolyphosphate, were analyzed by the thiobarbituric acid (TBA) method and the headspace GC technique. Significant positive correlations were obtained between TBA numbers and the areas of 3 major peaks of the headspace profiles, indicating the applicability of the rapid headspace GC method for the determination of oxidative changes in chicken meat.
Temperature-Independent Pectin Gel Method for Coliform Determination in Dairy Products: Collaborative Study
Authors: Roth Jonathan N , Bontrager Gordon L 
Published: February 2020

Abstract
Ten laboratories participated in a collaborative study to compare a pectin-based violet red bile (VRB) method with the VRB agar-based standard method for estimation of coliform bacterial counts in 7 different dairy food groups: cream, cheddar cheese, cottage cheese, homogenized milk, raw milk, sour cream, and yogurt. Each laboratory analyzed 8 samples of each food group as sample pairs prepared at high, medium, and low inoculum levels, and an uninoculated control pair. Overall mean log counts were higher for the pectin gel method in 18 of 21 cases (7 samples at 3 inoculum levels); 12 results were significantly higher (P &lt; 0.01) than those for the VRB agar method. Of the 3 higher VRB agar method means, 2 were not significant at P &lt; 0.10, and one was of borderline significance (0.05 &lt; P &lt; 0.06). Repeatability variation (sr) favored the pectin gel method in 14 of 21 cases; 7 were highly significant differences (P &lt; 0.01). None of the 7 results favoring the VRB agar method was statistically significant. Reproducibility variation (sR) favored the pectin gel method in 14 of 21 results. These data indicate that the pectin gel method gives higher recovery of coliforms with better precision than does the VRB agar method, and strongly support the suitability of the pectin gel method as an alternative to the agar-based VRB method for coliform counts in dairy products. The pectin gel method has been adopted official first action.
Fluorescent Enzyme Immunoassay for Rapid Screening of Salmonella in Foods: Collaborative Study
Authors: Flowers Russell S , Klatt Mary Joan , Keelan Susan L , Swaminathan B , Gehle Warren D , Chandonnet Heidi E 
Published: February 2020

Abstract
A collaborative study was performed in 13 laboratories to validate an enzyme immunoassay (EIA) procedure for rapid detection of Salmonella in foods. The EIA was compared with the standard culture procedure for detection of Salmonella in 6 food types: ground black pepper, soy flour, dried whole eggs, milk chocolate, nonfat dry milk, and raw deboned turkey. Uninoculated and inoculated samples were included in each food group analyzed. There was no significant difference in the proportion of samples positive by the EIA and culture procedures at the 5% level for any of the 6 foods. The enzyme immunoassay screening method has been adopted official first action as a rapid screening method for detection of Salmonella.
Simultaneous Gas Chromatographic Determination of Carbofuran, Metalaxyl, and Simazine in Soils
Authors: Getzin Louis W , Cogger Craig G , Bristow Peter R 
Published: February 2020

Abstract
A method for extraction, cleanup, and simultaneous gas chromatographic detection of carbofuran, metalaxyl, and simazine in soils has been developed. Pesticide residues were extracted from soil with acetone containing 10% 0.2M HCl-KCl buffer (pH 2.0), cleaned up with methylene chloride-carbonate buffer (pH 10.7) solvent partitioning and solid-phase extraction on disposable silica gel columns, and quantitated with gas chromatography using a Supelcowax 10 megabore capillary column and a nitrogen-selective detector. Method limits of detection were 0.02 μg/g for the 3 pesticides in surface soils (0-30 cm depths) and 0.02,0.02, and 0.005 μg/g in soils below 30 cm (subsoils) for carbofuran, metalaxyl, and simazine, respectively. Recoveries for carbofuran, metalaxyl, and simazine were 92.6 ± 5.5, 93.6 ± 5.0, and 88.4 ± 6.7%, respectively, when soil samples were spiked with pesticide concentrations ranging from 0.02 to 2.0 μg/g.
Application of Analytical Standards in Method Development: Selected Chlorinated Phenols and Herbicides
Authors: Fast Douglas M , Reddy V Vikram , Ashley David L , Holler James S 
Published: February 2020

Abstract
Pure analytical standards are key components in the successful development of accurate analytical methods. When such compounds are unavailable commercially, a laboratory synthesis activity can provide such materials for use in method development. An example of such an approach is the synthesis of ethyl ethers of chlorinated phenols and ethyl esters of several phenoxy herbicides. Individual synthesis steps and the characterization of such materials are described. The use of such analytical standards in method development is vital for defining method characteristics. In addition, such materials are helpful in diagnosing chromatographic and mass spectral problems in the course of this work. Key mass spectral information including parent and daughter scans obtained from these analytical standards by using tandem mass spectrometry provide the basis for a new analytical method with increased sensitivity and specificity.
Closed Vessel Sample Decomposition by Microprocessor Controlled High Temperature/ Pressure Asher for Elemental Analysis by Inductively Coupled Argon Plasma Emission Spectrometer
Authors: White R Thomas 
Published: February 2020

Abstract
A safe, reliable, and efficient method is described for automated acid decomposition of biological samples, agricultural food products, and environmental material under high temperature and pressure. A high temperature/pressure asher that provides temperatures up to 320°C and pressures up to 100 bars (1450 psi) is used to heat 5 mL of ultrapure acid 4 h for complete sample decomposition. The unit is microprocessor-controlled with up to 5 programmable temperature levels and ramp time intervals. These levels and intervals are displayed on a CRT screen. Both temperature and pressure program set points and actual readings inside the autoclave can be monitored by an analyst as the decomposition program progresses. Biological samples and agricultural food products of 1.0 g each are weighed into 70 mL closed quartz vessels for acid digestion. The digested samples are analyzed by using an inductively coupled argon plasma (ICP) emission spectrometer for aluminum, boron, calcium, iron, lead, magnesium, manganese, phosphorus, potassium, sodium, strontium, sulfur, and zinc. Environmental material of 0.2 g each is weighed into 20 mL glassy carbon vessels for digestion and ICP analysis for calcium, iron, lead, magnesium, manganese, nickel, phosphorus, potassium, sodium, strontium, sulfur, titanium, and zinc. The average recovery for 31 elemental standards evaluated by digestion in the high temperature/ pressure asher provided an average recovery of 98.7%.
Determination of Size Distribution of Fat Globules in Intravenous Fat Emulsions by Photon Correlation Spectroscopy
Authors: Cyr Terry D , Lawrence Robert C , Lovering Edward G 
Published: February 2020

Abstract
A photon correlation spectroscopy method has been developed to characterize the size distribution of fat globules in intravenous fat emulsions (IFE) in terms of mean diameter, standard deviation of the distribution, and percentage of large particles outside the distribution. Mean fat globule diameters of samples of all IFE products available in Canada were about 0.3 μm, similar to values reported in the literature. The methodology is sufficiently sensitive to detect the presence of 5% by weight of 2 μm polystyrene microspheres in an intravenous fat emulsion. The effect of changes in instrument settings and variables on the results has been evaluated.
Determination of Water-Insoluble Cell Walls in Feeds: Interlaboratory Study
Authors: Carré Bernard , Brillouet Jean-Marc 
Published: February 2020

Abstract
A collaborative study was conducted to test a new rapid procedure for determination of water-insoluble cell wall (WICW) content in feeds. In the method, starch is solubilized near boiling temperature with Termamyl, a heat-stable alpha-amylase, and proteins are solubilized at 40 °C with sodium dodecylsulfate and Pronase. Then, the organic matter of the residue is determined by incineration. Three hours were required to treat 12 different samples, including solubilization treatments, filtrations, and rinses. Eleven unknown products including 9 common feedstuffs of various origin and 2 mixed diets for poultry were analyzed by 7 analysts in France. Coefficients of variation ranged from 2.3 to 6.1%. The results were compared to those for water-insoluble dietary fiber (WIDF), total dietary fiber, and neutral detergent fiber. Agreement was best with the water-insoluble dietary fiber procedure. For most samples, the ratios of WIDF/WICW ranged from 0.981 to 0.842. The differences between WICW and WIDF values correspond to cell wall protein which is accounted for in WICW, but not in WIDF.
Determination of Arsenic and Selenium in Whole Fish by Continuous-Flow Hydride Generation Atomic Absorption Spectrophotometry
Authors: Brumbaugh William G , Walther Michael J 
Published: February 2020

Abstract
A combined wet chemical and dry ash digestion and use of a continuous- flow hydride generator coupled with a flame-heated quartz cell enabled the simple, precise, and highly automated atomic absorption determination of arsenic and selenium in tissues of whole fish. Percent relative standard deviation averaged 4% for each element; method detection limits (μg/g dry wt) were about 0.06 for arsenic and 0.04 for selenium. Digestion of samples proceeded with little operator attention and without perchloric acid. Analysis for arsenic as As(V) simplified sample preparation but care had to be exercised to avoid interferences from high concentrations of selenium.
Levels of Polychlorinated Biphenyls and Pesticides in Bluefish Before and After Cooking
Authors: Trotter William J , Corneliussen Paul E , Laski Ronald R , Vannelli Joseph J 
Published: February 2020

Abstract
Similar levels of polychlorinated biphenyls (PCBs), pesticides, and fat were found in 20 correlated uncooked and cooked (baked) bluefish fillets. Fillets averaged 2.5 ppm PCBs as Aroclor 1254 (whole basis) before cooking; after cooking, with the oil drippings and skin discarded, the average PCB level was 2.7 ppm. Although PCBs, lipophilic pesticides, and fat were lost along with oil drippings and skin that were discarded after cooking, the moisture loss in the fillets during cooking compensated for these weight losses almost completely. After the fillets were cooked and the oil drippings and skin were discarded, the PCB content of the fillets was 27% lower on the average.
Tolerance Setting Process in the U.S. Environmental Protection Agency
Authors: Trichilo Charles L , Schmitt Richard D 
Published: February 2020

Abstract
The U.S. Environmental Protection Agency (EPA) is responsible for setting tolerances for pesticide residues in food, under the authority of the Federal Food, Drug, and Cosmetic Act. The residue chemistry data required to set tolerances include metabolism in plants and animals, analytical methods, magnitude of the residue, and concentration in processed foods. A key aspect of tolerance-setting procedures is the identity of the residue in the matrix of concern; without knowledge of the chemical moieties that occur as residues, it is impossible to develop suitable methods or generate meaningful residue data. For new chemicals, EPA carries out a single-laboratory validation of the analytical method needed to generate residue data and to enforce tolerances. Tolerance enforcement methods need to be rapid and inexpensive and to use commercially available equipment and reagents. Methods are more complex for many newer pesticides, which are polar compounds that leave low levels of residue. EPA now requires that the registrants of older pesticides, for which methods are not acceptable by today's standards, must develop better methods.
Aflatoxins in Domestic and Imported Foods and Feeds
Authors: Wood Garnett E 
Published: February 2020

Abstract
Aflatoxins, metabolic products of the molds Aspergillus flams and A. parasiticus, may occur in foods and feeds. These toxins cannot be entirely avoided or eliminated from foods or feeds by current agronomic and manufacturing processes and are considered unavoidable contaminants. To limit aflatoxin exposure, the U.S. Food and Drug Administration (FDA) has set action levels for these toxins in foods and feeds involved in interstate commerce. FDA continually monitors food and feed industries through compliance programs. This report summarizes data generated from compliance programs on aflatoxins for the fiscal year 1986. Commodities sampled included peanuts and peanut products, corn and corn products, tree nuts, cottonseed, milk, spices, manufactured products, and miscellaneous foods and feeds. Correlations were highest between aflatoxin contamination and geographical areas for corn/corn products and cottonseed/cottonseed meal. Higher incidences of aflatoxin contamination in corn and corn products designated for human consumption were observed in samples collected in the southeastern states (32 and 28%, respectively). A higher incidence of contamination was observed in corn designated for animal feed from Arkansas-Texas (74%) than from the southeastern states (47%). Only 3% of feed corn from corn belt states contained detectable aflatoxins. All aflatoxin-contaminated cottonseed was collected in the Arizona-California area; 80% of cottonseed meal analyzed from this area also contained detectable levels of aflatoxins. No aflatoxin Mi was detected in any of the 182 samples of fluid milk and milk products examined. The percentage of samples that contain measurable levels of aflatoxins is expected to vary with commodities from year to year; thus, the 1986 information can be used as a baseline for comparison to determine the effectiveness of control efforts exerted by the food and feed industries.
Polarographic Determination of Famotidine in Dosage Forms
Authors: Squella Juan A , Valencia Gladys , Lemus Igor , Nunez-Vergara Luis J 
Published: February 2020

Abstract
Famotidine, which cannot be electrochemically reduced at the dropping mercury electrode, exhibits catalytic proton reduction waves. The peak obtained by in-phase ac polarography in neutral media is of analytical interest. Recovery studies and individual tablet assays are described. Results show adequate precision and accuracy. Sample preparation is not time consuming, and no excipient separation is required.
Determination of Enantiomeric Purity of Tranylcypromine Sulfate by Proton Magnetic Resonance Spectroscopy with Chiral Lanthanide Shift Reagent
Authors: Hanna George M , Lau-Cam Cesar A 
Published: February 2020

Abstract
Optimum experimental conditions were developed for determination of the optical purity of samples of tranylcypromine sulfate by proton magnetic resonance spectroscopy after complexation with the chiral lanthanide chelate Eu(hfc).3. At a substrate concentration of 0.25M (0.125M as sulfate) in CDC13 and an Eu(hfc)3 to substrate molar ratio of 1, the methine proton geminal to the amino group in the cyclopropane ring showed the largest induced shift and largest enantiomeric induced shift difference. From the relative intensities of the resolved (+)-CH-NH2 protons (15.77 ppm) and (-)-CH-NH2 proton (16.04 ppm), the enantiomeric purity and percentage compositions were readily calculated. The mean ± SD recovery of (+)- tranylcypromine sulfate from synthetic enantiomeric mixtures was 101.02 ± 2.59 (n = 6).
Determination of Nicarbazin in Chicken Tissues By Liquid Chromatography and Confirmation of Identity By Thermospray Liquid Chromatography/Mass Spectrometry
Authors: Lewis Jerry L , Macy Thomas D , Garteiz Daniel A 
Published: February 2020

Abstract
A liquid chromatographic method is described for the quantitative measurement of nicarbazin in chicken liver, fat, muscle, and skin tissues. The 4,4'-dinitrocarbanilide (DNC) portion of nicarbazin is extracted from tissues with ethyl acetate. After filtration and evaporation, the extract is purified by liquid-liquid partitioning with acetonitrile-hexane and alumina cartridge chromatography. DNC is separated and measured by reverse-phase liquid chromatography (RPLC) with an octadecylsilyl (ODS) column and a UV detector set at 340 nm. The overall average recovery of DNC added to tissues was 83.4 ±3.1%. The lowest level validated in tissues by this procedure was 0.10 ppm. The limit of detection was estimated to be 0.020 ppm. This method provides a sensitive, selective, rapid, and reproducible alternative to existing purification, separation, and detection techniques, such as differential pulse polarography and colorimetry, for determination of nicarbazin in chicken tissues. Identity of DNC is confirmed by subjecting the purified extracts to thermospray-LC/mass spectrometric analysis using negative-ion detection and selected ion monitoring. Three structural-indicating ions at m/z 302,272, and 164 are monitored in the thermospray-mass spectrum which are characteristic of the DNC molecule.
Liquid Chromatographic Determination and Gas Chromatographic-Mass Spectrometric Confirmation of Lasalocid Sodium in Bovine Liver: Interlaboratory Study
Authors: Frank Lesley R , Barnes Charlie J 
Published: February 2020

Abstract
The U.S. Food and Drug Administration (FDA) sponsored an interlaboratory study of a liquid chromatographic determinative procedure for lasalocid sodium in chicken skin with adhering fat. Four laboratories analyzed 35 dosed tissue samples and 82 fortified tissue samples containing lasalocid at levels ranging from 0.1 to 0.6 ppm. Samples were homogenized with acetonitrile, washed with hexane, and partitioned into the mobile phase prior to analysis liquid chromatography with fluorescence detection. The results of the interlaboratory study showed good reproducibility for fortified samples. Fortification levels, average recoveries, and interlaboratory percent coefficients of variation were as follows: 0.6 ppm, 0.57 ppm, and 9.7; 0.3 ppm, 0.25 ppm, and 9.1; and 0.15 ppm, 0.14 ppm, and 7.0, respectively. Data for analysis of the dosed tissue also showed good agreement among the laboratories.
Microscopic Detection and Identification of Various Substitute Vegetable Tissues in Ground Horseradish
Authors: Galacci Raymond R 
Published: February 2020

Abstract
Turnip root, parsnip root, potato tuber, and corn kernels have been used as adulterants in the preparation of horseradish sauce and horseradish powder. The diagnostic histological features of horseradish root and its known adulterants are described and illustrated as viewed through a polarizing microscope with cross polars and a first order red plate. A procedure which can be used to detect any of the known adulterants in horseradish is described. The adaptation of a previously reported semiquantitative method is also discussed.
Determination of Orotic Acid by Liquid Chromatography as a Criterion for Calculating Nonfat Milk Solids in Milk Bread
Authors: Bui Lap V 
Published: February 2020

Abstract
A sensitive and reproducible isocratic liquid chromatographic method is described for the determination of orotic acid levels in skim milk powder and milk bread. The results are used to calculate the nonfat milk solids content in milk bread. Sample preparation is simple and rapid and produces an extract which, after passing through an on-line cleanup system, has a minimum adverse effect on the performance and life of the analytical column. Mean recoveries of 96-105% were obtained with coefficients of variation in the range 1.0-8.5% and a detection limit of 5 mg/kg. The liquid chromatographic method was more sensitive than the standard colorimetric method, while results obtained by both methods agreed closely.
Microbiological Survey of Selected Imported Spices and Associated Fecal Pellet Specimens
Authors: Satchell Felicia B , Bruce Verneal R , Allen Geraldine , Andrews Wallace H , Gerber Harriet R 
Published: February 2020

Abstract
A microbiological survey was performed on 4 selected imported spices: black peppercorns, white peppercorns, coriander, and fennel seed. Aerobic plate count values ranged from 104 to 107 colonyforming units (CFU)/g for black and white peppercorns and from 103 to 105 CFU/g for coriander and fennel seed. Combined results of the 3-tube most probable number procedure and the API 20E kit indicated the presence of Escherichia coli in 4 test samples of black peppercorns, 1 test sample of white peppercorns, and 1 test sample of coriander. Two test samples of black peppercorns were positive for Salmonella contamination. Among the various Enterobacteriaceae isolated from the spices, Enterobacter cloacae and Klebsiella pneumoniae were found most frequently in all spice types. Of 18 mammalian and avian fecal pellets removed from the spices and analyzed microbiologically, E. coli was found in only 2 pellet specimens. There was no apparent relationship between the enteric microflora found in spices and those found in the fecal pellets.