bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapid and Simple Method for Determination of Cholesterol in Processed Food
Authors: Naeemi Esmaeel D , Ahmad Nissar , Al-Sharrah Tahani K , Behbahani Montaha 
Published: February 2020

Abstract
An improved method for determination of cholesterol in processed food with only one extraction and without solvent removal was developed. Total time to analyze a sample including gas chromatographic (GC) analysis is 45 min. Food samples spiked with internal standard are hydrolyzed in a screw-capped vial with saturated methanolic KOH. Cyclohexane is added to the mixture, and the upper layer is analyzed by GC on a capillary column. Average recoveries of spiked white eggs are 99 ± 0.5%. Fifteen types of processed food containing shrimp, fish, meat, cheese, eggs, and vegetables were analyzed with this method and with the AOAC method.
Dairy Product Analysis: Identification of Microorganisms by Mid-Infrared Spectroscopy and Determination of Constituents by Raman Spectroscopy
Authors: Fehrmann Angela , Franz Monika , Hoffmann Andreas , Rudzik Lutz , Wüst Eberhard 
Published: February 2020

Abstract
Identification of microorganisms by traditional microbiological methods is time consuming. The German Federal Health Office has developed a method using mid-infrared spectroscopy to identify microorganisms rapidly. This method has been modified for application to microorganisms important in the dairy industry. Mid- and near-infrared spectroscopies are well-established methods for quantitative measurements of fat, protein, lactose, and solid content in a variety of products. A disadvantage of both methods is the huge absorption due to water; extraction of other components is complicated and can be achived only statistically. With Raman spectroscopy, water causes less absorption. We investigated the use of Raman spectroscopy as a quantitative method for milk powder.
Polymerase Chain Reaction–Restriction Fragment Length Polymorphism Analysis: A Simple Method for Species Identification in Food
Authors: Meyer Rolf , Höfelein Christiane , Lüthy Jürg , Candrian Urs 
Published: February 2020

Abstract
The polymerase chain reaction (PCR) technique was applied to meat species identification in marinated and heat-treated or fermented products and to the differentiation of closely related species. DNA was isolated from meat samples by using a DNA-binding resin and was subjected to PCR analysis. Primers used were complementary to conserved areas of the vertebrate mitochondrial cytochrome b (cytb) gene and yielded a 359 base-pair (bp) fragment, including a variable 307 bp region. Restriction endonuclease analysis based on sequence data of those fragments was used for diffferentiation among species. Restriction fragment length polymorphisms (RFLPs) were detected when pig, cattle, wild boar, buffalo, sheep, goat, horse, chicken, and turkey amplicons were cut with Alul, Rsal, Taql, and Hinfl. Analysis of sausages indicates the applicability of this approach to food products containing meat from 3 different species. The PCR–RFLP analytical method detected pork in heated meat mixtures with beef at levels below 1%, and the method was confirmed with porcine- and bovine-specific PCR assays by amplifying fragments of their growth hormone genes. Inter- and intraspecific differences of more than 22 animal species with nearly unknown cytb DNA sequences, including hoofed mammals (ungulates), and poultry were determined with PCR–RFLP typing by using 20 different endonucleases. This typing method allowed the discrimination of game meats, including stag, roe deer, chamois, moose, reindeer, kangaroo, springbok, and other antelopes in marinated and heat-treated products.
Microwave-Assisted Extraction as an Alternative to Soxhlet, Sonication, and Supercritical Fluid Extraction
Authors: Lopez-A Vila Viorica , Young Richard , Teplitsky Nataly 
Published: February 2020

Abstract
Microwave-assisted extraction (MAE), Soxhlet, soni cation, and supercritical fluid extraction (SFE) were compared in their ability to extract 95 compounds listed in U.S. Environmental Protection Agency Method 8250. Freshly spiked soil samples and 2 standard reference materials were extracted with hexane-acetone (1 + 1) by MAE and Soxhlet extraction, with methylene chloride-acetone (1 + 1) by sonication extraction, and with supercritical carbondioxide modified with 10% methanol by SFE. Results indicate that MAE is a promising extraction technique. Of 94 compounds for which we are reporting data, 51 compounds gave MAE recoveries of &gt;80%; 33,50-79%; 8,20-49%; and 2, &lt;19%. Soxhlet extraction gave very similar results: 50 recoveries were &gt;80%; 32,50-79%; 8,20-49%; and 4, &lt;19%. Sonica tion recoveries were slightly higher: 63 values were &gt;80%; 25,50-79%; 4,20-49%; and 2, &lt;19%. SFE recoveries were the lowest: 37 values were &gt;80%; 37, 50-79%; 12,20-49%, and 8, &lt;19%. MAE gave the best precision: relative standard deviations (RSDs) were &lt;10% for 90 of 94 compounds. Soxhlet extraction gave the worst precision: only 52 of 94 samples gave RSDs ≤10%. Although MAE looks promising, 15 polar basic compounds extracted at 115°C with hexane acetone for 10 min (1000 W power) gave poor recoveries. Because no technique gave acceptable recoveries for these polar compounds, we investigated their extraction with MAE using acetonitrile at 50° and 115°C. Ten of the 15 compounds were quantitatively recovered (&gt;70%) with acetonitrile at 115°C.
Estimated Content Percentages of Volatile Liquids and Fat Extractables in Ready-to-Eat Foods
Authors: Daft James L , Cline J Kevin , Palmer Rosetta E , Sisk Ronald L , Griffitt Kenneth R 
Published: February 2020

Abstract
Content percentages of volatile liquids and fat ex tractables in 340 samples of ready-to-eat foods were determined gravimetrically. Volatile liquids were determined by drying samples in a microwave oven with a self-contained balance; results were printed out automatically. Fat extractables were ex tracted from the samples with mixed ethers; ex tracts were dried and weighed manually. The sam ples, 191 nonfat and 149 fatty (containing ca 2% or more fat) foods, represent about 5000 different food items and include infant and toddler, ethnic, fast, and importeditems. Samples were initially pre pared for screening of essential and toxic elements and chemical contamination by chopping and mix ing into homogenous composites. Content determi nations were then made on separate portions from each composite. Content results were put into a da tabase for evaluation. Overall, mean results from both determinations agree with published data for moisture and fat contents of similar food items. Co efficients of variation, however, were lower for de termination of volatile liquids than for that of fat ex tractables.
Interpretation of Combined H SNIF/NMR and C SIRA/MS Analyses of Fruit Juices To Detect Added Sugar
Authors: Martin Gilles G , Hanote Valérie , Lees Michéle , Martin Yves-Loïc 
Published: February 2020

Abstract
The site-specific natural isotopic fractionation studied by nuclear magnetic resonance (SNIF/NMR) method measures site-specific isotope contents in a variety of organic compounds by deuterium nuclear magnetic resonance spectroscopy. This technique, together with SIRA/MS (stable isotope ratio analysis/mass spectrometry) provides a powerful tool for food authentication and characterization. By using the ethanol resulting from sugar fermentation as a molecular probe, SNIF/NMR (deuterium) and SIRA/MS (13C) have been used together for authentication of fruit juices. The influence of deu terium content of the fermentation water on the iso topic parameters is shown and a means for normal izing the results is proposed. A large number of authentic juices have been analyzed to define the variation of isotopic ratios in natural juices. On the basis of these data, a set of rules was designed to enable interpretation of isotopic parameters in terms of possible adulteration of fruit juices by sugar addition. Results of analyses of Florida orange juice are presented. Orange juice samples from Brazil and Israel are included as 2 extreme cases. Assignment limits for a sample of orange juice of unknown origin also are given. These assignment limits are also provided for apple and grapefruit juices.
Identification of Ambergris from the New Bedford Whaling Museum by Nuclear Magnetic Resonance Spectroscopy
Authors: Moniz George A , Hammond Gerald B 
Published: February 2020

Abstract
A new method for the separation and identification of ambrein in ambergris using adsorption chromatography and 1H and 13C Fourier transform nuclear magnetic resonance spectroscopy (FT-NMR) is presented. We demonstrated the effectiveness of this method by analyzing an approximately 85-year-old sample of suspected ambergris from the New Bedford Whaling Museum (New Bedford, MA). Results prove that ambrein remains a major constituent of ambergris even after 85 years of storage under ordinary conditions.
Liquid Chromatographic Determination of Nalidixic Acid in Pharmaceutical Preparations
Authors: Walker Samuel T 
Published: February 2020

Abstract
A simple, rapid, and environmentally safe liquid chromatographic (LC) method was developed for the qualitative and quantitative determination of pharmaceutical preparations of nalidixic acid. The new method was applied to commercial preparations of tablets and a suspension of nalidixic acid and found to be satisfactory for both quantitative and qualitative determinations. Previous LC methods either used chloroform to extract, which we were trying to eliminate, or used a mobile phase of about pH 2.5, which will destroy the column coating. TheLC system for the new method uses sul fanilic acid as internal standard, a μ-Bondapak C18 column, and a mobile phase of methanol, 0.0045M dibasic potassium phosphate, and 0.0072M hexadecyltrimethyiammmonium bromide. The detection wavelength is 254 nm. The sample is dissolved in methanol, and an aliquot is injected through a 20 μL injection loop. Average recoveries ranged from 99.4 to 101.3%.
Salmonella Detection in Dried Milk Products by Motility Enrichment on Modified Semisolid Rappaport-Vassiliadis Medium: Collaborative Study
Authors: Bolderduk Robert F , Milas John E ,   Collaborators:, Asperger H , Becker H , Chatron S , Cordier J L , DeSmedt J , Gonzalez D , Hammers A , Hoekstra J , Kanitz L , McDonagh S , Nowacki R , Oggel J , Quinlan J , Stolpenir L , Trottier Y L , Van Gestel G , Van Oudenallen A , West W , Zschaler R 
Published: February 2020

Abstract
A collaborative study involving 19 laboratories was performed to validate motility enrichment on modified semisolid Rappaport-Vassiliadis (MSRV) medium for rapid detection of motile Salmonella in dried milk products. The MSRV method was compared with the AOAC culture method for detection of Salmonella in nonfat milk powder, whole milk powder, whey powder, casein powder, and butter milk powder. Samples were artificially inoculated with Salmonella at 2 levels of contamination. Un-inoculated control samples were included for each type of product. The sensitivity rates were 100% for the MSRV method and 99.0% for the AOAC culture method, while the specificity rate was 100.0% for both methods. Only for the samples of whey powder, which were inoculated with H2S negative S. tennessee, was there a significant difference in the proportion of samples positive by MSRV and the culture procedure. The MSRV method for detection of motileSalmonella in dried milk products has been adopted first action by AOAC INTERNATIONAL.
Determination of Patulin in Apple Juice by Liquid Chromatography: Collaborative Study
Authors: Brause Allan R , Trucksess Mary W , Thomas Frederick S , Page Samuel W ,   Collaborators:, Burke J , Tanner A , Hammack S , Woodward B B , Post S , Simmons D , Cherix G , Kennedy M , Lewis S , English N , Coppola E D , Kline L , Coopersmith A , Foos J F , Eisele T A , Krueger D A ,   Collaborators:, Hofsommer H J , MacDonald S , Hesford F , Lea A , Symonds P , Martin G , Acar J , Eksi A , Ardenghi R , Weiss J , Lee B , Woidich H 
Published: February 2020

Abstract
An AOAC International-International Union of Pure and Applied Chemistry-International Fruit Juice Union (AOAC-IUPAC-IFJU) collaborative study was conducted to evaluate a liquid chromatographic (LC) procedure for determination of patulin in apple juice. Patulin is a mold metabolite found naturally in rotting apples. Patulin is extracted with ethyl acetate, treated with sodium carbonate solution, and determined by reversed-phase LC with UV detection at 254 or 276 nm. Water, water-tetrahydrofuran, or water-acetonitrile was used as mobile phase. Levels determined in spiked test samples were 20, 50,100, and 200 μg/L. A test sample naturally contaminated at 31 μg/L was also included. Twenty-two collaborators in 10 countries analyzed 12 test samples of apple juice. Recoveries averaged 96%, with a range of 91-108%. Repeatability relative standard deviations (RSDr) ranged from 10.9 to 53.8%. The reproducibility relative standard deviation (RSDR) ranged from 15.1 to 68.8%. The LC method for determination of patulin in apple juice has been adopted first action by AOAC INTERNATIONAL.
Assessment of Immunochemical Methods for the Analysis of Trichothecene Mycotoxins in Naturally Occurring Moldy Corn
Authors: Park Joung J , Chu Fun S 
Published: February 2020

Abstract
The efficacy of various immunochemical methods for simultaneous analysis of different trichothe-cene mycotoxins in corn samples naturally contaminated with various Fusarium molds was evaluated. Antibodies against either T-2 tetraol tetraacetate (T-2-4ol-4Ac) or deoxynivalenol triacetate (Tri-Ac-DON) were used in the enzyme- linked immunosorbent assay (ELISA) and radioimmunoassay (RIA) for total type A and total DON-related trichothecenes (TCTCs), respectively. Specific antibodies against T-2 toxin were used in an RIA for analysis of T-2 toxin alone. Analytical recoveries of T-2 toxin analyzed as T-2-4ol-4Ac by ELISA and T-2 toxin by RIA at 10-200 ppb were 83.5-123% and 81.8-110.6%, respectively. T-2 toxin accounts for about 30% of total type A TCTCs by both liquid chromatography (LC)-ELISA and RIA methods. The correlation coefficients (r) of total type A TCTC levels versus T-2 toxin level by RIA was 0.725 (p &lt; 0.0001). A good correlation (r = 0.84 and p = 0.04) also was found for T-2 toxin levels obtained by LC-ELISA and RIA methods. In addition to T-2 toxin, HT-2 toxin, diacetoxyscirpenol, and T-2 tetrol were found in samples containing high levels of type A TCTCs by LC-ELISA. For analysis of DON alone, samples were treated with a Sep-Pak C18 cartridge to remove other acetylated DONs before RIA. Recovery of DON after the C18 cartridge treatment was 90%. Overall analytical recoveries of DON as Tri-Ac-DON (sample with no C18 treatment) and DON alone (with C18 treatment) at 10-500 ppb were 81.3-94% and 72.7-104%, respectively. RIA revealed that DON accounts for about 50% of total DON-related TCTCs. The coefficient of correlation between total DON-related TCTCs and DON levels was 0.84 (p &lt; 0.0001).
Liquid Chromatographic Method for Determination of Total Avermectin Bi and 8,9-Z-Avermectin B1 Residues in Hops
Authors: Cobin Janice A , Johnson Nelson A 
Published: February 2020

Abstract
A liquid chromatographic method has been developed and validated for determination of avermectin B1 and 8,9-Z-avermectin B1 residues in dried hops. The dried hops are rehydrated and subsequently extracted with a methanol-water mixture.The aver- mectins are partitioned into hexane and the hexane extract is concentrated (purified) on an amino- propyl solid-phase extraction column. The purified extract is derivatized with trifluoroacetic anhydride, and the derivatized avermectins are analyzed by re versed-phase liquid chromatography with fluorescence detection. Recoveries of the avermectins fromdried hops fortified with approximately 51000 ng/g avermectin B1a or 8,9-Z-avermectin B1a ranged from 73 to 108% with an overall average recovery of 95%. The limit of quantitation is 5 ng/g (signal-to-noise ratio [S/N] &gt; 10), and the limit of detection is 2 ng/g (S/N &gt; 3) for each analyte. The assay procedure provides a simple, rapid, and sensitive method for monitoring the total avermectin residues in hops.
Determination of Diesel Fuel and Motor Oil in Water and Wastes by a Modified Diesel-Range Organics Total Petroleum Hydrocarbon Method
Authors: Draper William M , Dhaliwal Joginder S , Perera S Kusum , Baumann Frank J 
Published: February 2020

Abstract
The American Petroleum Institute method for determination of diesel-range total petroleum hydrocarbon (TPH) by gas-liquid chromatography with flame ionization detection was modified to allow simultaneous determination of motor oil. Motor oil elutes as a broad hump of unresolved alkanes and can be distinguished readily from diesel fuel and other fuel oils by its profile. The boiling point ranges for No. 2 diesel fuel and motor oil are C10– C21 and C21–C38, respectively, and these ranges define TPHs in diesel fuel (TPH-D) and motor oil (TPH- M). By this convention, less than 6% of No. 2 diesel is characterized as TPH-M, and less than 9% of motor oil is quantitated as TPH-D. Inlet discrimination was observed when motor oil was injected with a splitless injector. Accurate motor oil quantitation with splitless sample introduction requires calibration with the product or triacontane, which has a similar response factor. Detector response to motor oil (and other petroleum products) and a homologous series of n-alkanes was nearly constant when on-column injection was used. Instrument detection limit for motor oil was about 0.5 μg (split- less injection, total area under the curve), and the widest linear range (up to 100 μg) was obtained by subtracting the solvent chromatogram. Procedures for isolation of motor oil from oil-in-water (O/W) and water-in-oil (W/0) emulsions are described. Method detection limits for diesel fuel and motor oil in purified water were 0.041 and 1.5 mg/L, respectively.
Improved Gas Chromatographic Analysisof Organophosphorus Pesticides with Pulsed Splitless Injectiony
Authors: Wylie Philip , Uchiyama Katsura 
Published: February 2020

Abstract
Gas chromatographic (GC) analysis of 6 organo-phosphorus pesticides (methamidophos, acephate, omethoate, diazinon, dimethoate, and chlorpyrifos) was performed with cool on-column, splitless, and pulsed splitless injections and with nitrogen–phos phorus or mass-selective detection. The pulsed splitless technique uses a high column flow rate during injection to sweep the sample out of the inlet rapidly, reducing analyte loss due to adsorption or thermal decomposition. After injection, the column flow rate is automatically reduced to normal values for chromatographic analysis. Pesticide recoveries for splitless and pulsed splitless injections were determined by comparison of GC peak areas with those obtained with cool on-column injection. With conventional splitless injection at a column flow rate of 5 mL/min, recoveries of acephate, omethoate, and methamidophos were only 57, 63, and 71 %, respectively. Pulsed splitless methods with very fast injection flow rates dramatically improved recoveries, with all 6 pesticides falling in the 97–102% range. Because column flow rates are much less for GC with mass spectral detection (GC/MS), recoveries with splitless injection were lower and improvements with pulsed splitless injection were less dramatic for GC/MS. When splitless injection was used, recoveries of the 6 pesticides spiked into a green bean matrix were better than those of pesticides dissolved in pure solvent, presumably because matrix compounds compete with pesticides for active sites in the inlet. By using pulsed splitless injection of solvent standards with very fast initial column flow rates, systematic analyte losses in the inlet were eliminated, making recoveries of pesticides from solvent and green bean matrix very similar.
Determination of Allantoin in Biological, Cosmetic, and Pharmaceutical Samples
Authors: Bin Chen Xue , Matuszewski Wojciech , Kowalczyk Jan 
Published: February 2020

Abstract
Methods for determining allantoin in biological, cosmetic, and pharmaceutical samples are reviewed. The methods cover 3 main categories: spectrophotometry, alkalimetric titration, and chromatography (thin-layer and liquid). Comments are given on suitability for different sample types and on further development of methods for allantoin determination.
Determination of Tilmicosin in Bovine Milk by Liquid Chromatography with Ultraviolet Detection
Authors: Ngoh Maureen A 
Published: February 2020

Abstract
A method is described for determining tilmicosin in bovine milk by liquid chromatography with ultraviolet (UV) detection. Samples are defatted by centrifugation. The lower skim layer is cleaned on a C18 solid-phase extraction cartridge. The extract is concentrated and analyzed with a reversed-phase phenyl column with UV detection at 280 nm. The method was validated with control milk fortified at 50,100, and 200 ng/mL. Average recoveries (and intralaboratory coefficients of variation) were 97% (9%), 98% (5%), and 101% (3%), respectively. The limit of quantitation is approximately 20 ng/mL, and the limit of detection is approximately 13 ng/mL. The method was tested on milk from a cow dosed with tilmicosin.
Determination of Sugars, Starches, and Total Dietary Fiber in Selected High-Consumption Foods
Authors: Li Betty W 
Published: February 2020

Abstract
A general scheme has been developed to determine sugars, starches, and total dietary fiber (TDF) in half-gram freeze-dried subsamples of various foods (or wet samples containing about 0.5 g dry matter). Duplicate subsamples are extracted for free sugars with 80% methanol, dried, derivatized to their trimethylsilylated oximes or ethers, and quantitated by gas–liquid chromatography (GLC). Residues after 80% methanol extraction are incubated with a solution containing amyloglucosidase in acetate buffer. Hydrolyzates are centrifuged, and duplicate aliquots are removed for glucose determination by GLC. Starch content is calculated as glucose (g/100 g) × 0.9. Remaining hydrolyzates are diluted with 4 volumes of 95% ethanol, left at room temperature for 1 h, and then filtered through glass crucibles matted with Celite filter aid. The weight of dry residues are corrected for residual crude protein and ash, and the resulting values are taken to be the TDF content of a sample. A variety of high- consumption foods selected by the Nutrient Data Laboratory of the Agricultural Research Service were analyzed for carbohydrate fractions by this method. Values for total sugar and dietary fiber were compared with those obtained by a commercial laboratory using different methods.
Automated Spectrophotometric Method Using 2,2’-Dithiodipyridine Acid for Determination of Cholinesterase in Whole Blood
Authors: Cerón Jose J , Palacio María J Fernandez Del , Bernal Luis J , Gutierrez Cándido 
Published: February 2020

Abstract
An automated method using 2,2’-dithiodipyridine (2-PDS) as chromophore for determination of wholeblood cholinesterase activity was developed. Assay procedures, optimal concentrations of chromophore and substrate, detection limit, precision, backgrounds, and sensitivity of the method were compared with those of an earlier automated method based on the Eilman method and using 5,5’-dithiobis(2-nitrobenzoic acid) (DTNB) as chromophore. The new method has the advantages of automation (resulting in increase throughput rate and decrease in amount of reagents used) and good precision and sensitivity. Sample dilutions also are reduced in the new method because hemoglobin interference is less.
Effect of USP Apparatus 1 and 2 at Different Rotational Speeds on Dissolution of Niacin Formulations
Authors: Kirchhoefer Ross D , Hamilton Jimmy F 
Published: February 2020

Abstract
Forty-four niacin formulations were examined by the United States Pharmacopeia dissolution test, consisting of 0.1 N HCl with apparatus 1 and 2. Each formulation was tested with apparatus 1 (basket) at 100 rpm and apparatus 2 (paddle) at 50 and 100 rpm. Dissolution results varied widely among manufacturers.