bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Polydextrose (Polymer) and Residual Monomers in Polydextrose by Liquid Chromatography
Authors: Thomas John W , Brown Donna L , Hoch Daniel J , Leary John J , Dokladalova Jarmila 
Published: February 2020

Abstract
A simple, liquid chromatographic method has been developed for determination of the reduced-calorie food additive polydextrose—a water soluble, 1 kilocalorie/gram bulking agent used extensively for manufacture of low-calorie food products. The method allows rapid determination of polydextrose content as well as determination of the minor components: dextrose, sorbitol, and 2 isomeric anhydroglucoses in bulk samples of polydextrose. The proposed method is superior to current Food Chemical Codex (FCC) methodologies for determination of polydextrose (phenol sulfuric acid spectrophotometry) and for determination of residual monomers [gas chromatographic (GC) determination as their trimethylsilyl derivatives]. The proposed method is more precise, considerably faster, and is safer to execute. The method uses a resin-based cation exchange column, 0.001N sulfuric acid mobile phase, and differential refractive index detection. Analyte response curves were linear; and data displayed good precision with coefficients of variation ranging from 1.1 to 1.6%. The efficiency, specificity, precision, and ruggedness of the method make it amenable to implementation in a routine quality control operation.
Capillary Gas Chromatographic Determination with Electron Capture Detector of β-Propiolactone in Biological Materials
Authors: Geahchan Aziz , Fouillet Bruno , Chambon Paul , Chambon Renee , Nouri Bahia 
Published: February 2020

Abstract
A method has been developed for the determination of β- propiolactone by derivatizing it to the volatile N-hexyl-3- heptafluorobutanoyloxypropanamide, which can be separated and Identified by a capillary CP-Sil 8 column, and detected by an electron capture detector (ECD). First, β- propiolactone is reacted with N-hexylamine to yield N-hexyl- 3-hydroxypropanamide. The fluorobutanoyl ester derivative is next prepared by using heptafluorobutyrlc acid anhydride in the presence of trimethylamine. The method Is very sensitive, simple, and specific, and can be used to detect and quantitate residual β-propiolactone In Iyophilized biological materials. The limit of detection is 0.2 ppm β-proplolactone in a 50 mg sample; however, because of variability at low levels, the limit of quantitation is 1 ppm. Detector response was linear for 2-500 ng β-propiolactone. Recoveries were 98% or greater from Iyophilized vaccines spiked at the 2-20 ppm level. No side products or interference peaks were observed in the derivatization reaction.
Comparison of Preston Agar and a Blood-Free Selective Medium for Detection of Campylobacter jejuni in Food
Authors: Peterz Mats 
Published: February 2020

Abstract
The present collaborative study compares recovery of Campylobacter Jejuni from food in 2 agar media. Six laboratories analyzed 8 samples each of chicken liver Inoculated with Campylobacter Jejuni. Samples were enriched in Preston broth and isolation was carried out on Preston agar (PA) and Campylobacter blood-free selective medium (CBFS), a charcoal- based medium with cefoperazone and amphoteracin as antibiotic supplements. There was no difference In the recovery rate between the 2 agar media; however, the specificity of CBFS was better than that of PA. There was a slightly better growth of Campylobacters, and competing organisms were more inhibited on CBFS than on PA.
Immunochromatography of Fusarochromanone Mycotoxins
Authors: Yu Jaehyuk , Chu Fun Sun 
Published: February 2020

Abstract
The present paper describes an enzyme-linked immunoassay (ELISA) used In combination with thin-layer chromatography (TLC) and liquid chromatography (LC) for determination of fusarochromanone (TDP) mycotoxins in barley, wheat, and a Fusarlum culture grown in rice and corn. The mycotoxins were first extracted from the sample with 100% methanol and subjected to TLC or LC without additional cleanup treatment. Individual fractions eluted from TLC or LC were acetylated, then analyzed by ELISA. Determinations of TDP toxins at levels as low as 0.1 and 0.5 ng were achieved by ELISA in combination with LC and TLC, respectively. The detection limit for TDP-1 in barley and wheat was about 20 ppb by ELISA alone as compared with a detection limit of 5 ppb by a combination of ELISA with either TLC or LC. Overall analytical recovery (% of added) of TDP-1 added to barley and wheat at 5,10, and 20 ppb of TDP-1 was 106.9 ± 15.3 and 113.2 ± 11.6 by LC-ELISA and 108.8 ± 9.1 and 110.4 ± 4.9 by TLC-ELISA, respectively. Analysis of extracts obtained from Fusarlum equiseti R6137 grown in corn and rice by the combination of TLC and ELISA revealed that diacetyl-TDP was also produced by this fungus in addition to TDP-1 and TDP-2. Comparable results were obtained when fungal extracts were subjected to ELISA, LC, and immunochromatography (i.e., combination of ELISA with either TLC or LC).
Modified Gas Chromatographic/Mass Spectrometric Method for Determination of Daminozide in High Protein Food Products
Authors: Faughnan Kevin T , Woodruff Marie A 
Published: February 2020

Abstract
A modified version of the Conditt and Baumgardner gas chromatographic/mass spectroscopic (GC/MS) method for determination of daminozide in peanut butter and raw peanuts is described. Daminozide in the food product is hydrolyzed to unsymmetrical dimethylhydrazine (UDMH) by sodium hydroxide digestion. The generated UDMH is distilled from the food matrix and captured by reaction with salicylaldehyde in a condensation trap. Resulting high pH distillates generated by peanuts and peanut products are adjusted back to a pH of 5-6 through addition of glacial acetic acid. After thermal incubation and extraction Into methylene chloride, salicylaldehyde dimethylhydrazone is separated from interferences by capillary GC and quantitated by MS using the selective ion monitoring (SIM) mode. Quantitation of daminozide is based on the ratio of the salicylaldehyde dimethylhydrazone molecular ion (m/z 164) to the molecular ion (m/z 153) of the Internal standard, 4-nitroanisole. Confirmation of daminozide identity is determined by relative Intensity of the m/z 164 Ion to the m/z 120 (C7H4ON) ion. Improved m/z 164 Ion Intensity and reduction of neighboring interferences due to acetic acid treatment permitted a daminozide detection limit of 0.005 ppm in a 50 g sample and an associated 0.02 ppm limit of quantitation. This modification is specific for high protein samples that generate high pH distillates such as peanuts and peanut products and is not specifically intended for analysis of low protein samples.
Listeria monocytogenes
Authors: Farber Jeffrey M 
Published: February 2020

Abstract
Listeria monocytogenes, one of the "new enemies" in food microbiology, is a human and animal pathogen that is widespread in nature. The organism Is a transient constituent of the Intestinal flora excreted by 1-10% of healthy humans. It is an extremely hardy organism and can survive for many years in the cold In naturally Infected sources. L monocytogenes has been Isolated from a wide variety of foods, including dairy products, meats, and fish. Although most of the foodborne listeriosis outbreaks have been linked to the consumption of dairy products, recent sporadic cases have been associated with meats, as well as other foods. It is now recognized that listeriolysln 0, a 60-kilodalton protein, is one of the major virulence factors of the organism. All strains of L monocytogenes are pathogenic by definition although some appear to be more virulent than others. There have been recent reports of hemolytic isolates of L monocytogenes, which are nonpathogenic for mice. Attachment to and penetration of cells also appear to be prerequisites for human infection. Cultural methodology for isolating the organism from foods has been in a state of flux since 1985. Rapid methods using both ELISA and DNA technology have been developed. Because of the widespread nature of the organism, it Is nearly Impossible to eliminate it from the food supply. However, by using a hazard analysis-critical control point approach, the health hazard associated with this organism can be reduced to a minimum.
Quantitation of the Nitrosamine 2-EthylhexyI-4-(N-Methyl-N-Nitrosoamino) Benzoate (NPABAO) in Sunscreen Products
Authors: Meyer Thomas A , Powell Jimmy B 
Published: February 2020

Abstract
We have devised a method to quantitate the nitrosamine, 2- ethylhexyM-(N-methyl-N-nitrosoamino) benzoate (NPABAO), In commercial products containing the sunscreen ingredient, Padimate 0. The method involves a minimum of cleanup steps to afford a nonaqueous extract from product emulsions suitable for analysis by a liquid chromatograph Interfaced to a thermal energy analyzer (LC/TEA). The method Is applicable to lotions, creams, and gels. Oils are normally soluble In the mobile phase and can be analyzed directly on the LC/TEA without additional cleanup procedures. The method has a minimum detectable limit of about 30 ppb and yields &gt; 80% recovery. It is highly reproducible and generates no NPABAO artifactually prior to quantitation on the LC/TEA Application of the method to 22 different commercial product formulas disclosed that the level of NPABAO in each of the products Is below 250 ppb, with 18 of the products containing less than 100 ppb. Of interest was the observation that musk ketone, a common fragrance constituent, produces a false-positive TEA response that can Interfere with accurate analysis of NPABAO content In typical commercial products
Rapid Extraction of Available Phosphorus in Fertilizers
Authors: Trimm Joe R , Farley James A 
Published: February 2020

Abstract
A method for the rapid extraction of available phosphorus In fertilizers Involves a single-step extraction that uses ethylenediaminetetraacetic acid (EDTA) as a complexing agent for Ca and Mg. This complexatlon of Ca and Mg enables the analyst to avoid the preliminary water extraction currently required. Sample extraction Is similar to that in method 963.03B(b),Official Methods of Analysis, 15th Ed. The extractant consists of a solution of dibasic ammonium citrate, disodium EDTA, and ammonium hydroxide. The extract or residue may be analyzed by existing AOAC methods. Results by the new extraction method agree favorably with those by existing methods. Analyses of samples from the Magruder and the Association of Florida Phosphate Chemists check sample programs agreed favorably with reported values for neutral ammonium citrate extraction.
Comparison of an ELISA-based Screening Test with Liquid Chromatography for the Determination of Aflatoxins in Corn
Authors: Beaver Rodney W , James Mary A , Lin Tay Y 
Published: February 2020

Abstract
An enzyme-linked immunosorbent assay (ELISA) screening test (CITE PROBE) was compared to liquid chromatography (LC) for the determination of aflatoxins in naturally contaminated corn samples. The CITE PROBE, with a positive/negative cutoff of 5 ng/g aflatoxin Bi, was correct (based on LC results) on 47 of 51 samples. Two of the Incorrect responses by the CITE PROBE were false positives on samples containing 4.4 ng/g and 4.1 ng/g aflatoxins by LC. Another incorrect response was a false negative on a sample containing 5.5 ng/g aflatoxins by LC. The fourth Incorrect response was a false positive on a sample containing 1.9 ng/g aflatoxins by LC. On the basis of these results, the CITE PROBE was determined to be a reliable screening method for the detection of % 5 ng/g aflatoxins in corn.
Determination of Mirex in Human Blood Serum Containing Poiychiorinated Biphenyis by Using Packed Column Gas Chromatography
Authors: Korver Margaret P , Burse Virlyn W , Needham Larry L , Green Vaughn E , Gray Deborah L , Rouse Mary A , Shelly Tracy L , Mortensen Kim B 
Published: February 2020

Abstract
An analytical method has been developed that uses electron capture/gas-llquld chromatography to determine Mirex In serum containing poiychiorinated biphenyis (PCBs) (Aroclor 1260). With this method, 0.2 ppb Mirex can be determined In 4 mL serum that also contains 10 ppb PCBs. The method provides approximately 70% recovery of Mirex at 1.0 and 3.5 ppb. The coefficients of variation are 4.5 and 4.6% at 1.0 and 3.5 ppb, respectively. In a cooperative study with the Ohio Department of Health, the Centers for Disease Control used this method to determine the extent of exposure of Salem, OH, residents to Mirex. Confirmation of Mirex was obtained by using high resolution gas chromatography and high resolution mass spectrometry.
An Analytical Survey of Aflatoxins in Tissues from Swine Grown in Regions Reporting 1988 Aflatoxin-Contaminated Corn
Authors: Stubblefield Robert D , Honstead John P , Shotwell Odette L 
Published: February 2020

Abstract
A joint project was undertaken by the Food Safety and Inspection Service (FSIS) and the Agriculture Research Service branches of the U.S. Department of Agriculture to determine the presence of aflatoxins in the U.S. meat supply during a drought year. In 1988, high incidences of aflatoxins occurred in corn grown in regions of the Midwest, Southeast, and South. Six states were identified as having serious aflatoxin contamination in their corn crop: Virginia, North and South Carolina, Texas, Iowa, and Illinois. Swine liver and pillars of diaphragm (muscle) tissues were sampled by federal FSIS inspectors in plants located in these states. A worstcase sampling plan was conducted. Samples were taken in January 1989 from hogs fed corn soon after harvest and in April 1989 from hogs fed corn originally stored and then fed in the spring. A modification of the official AOAC method for the thin-layer chromatography (TLC) determination of aflatoxins in animal tissue was used to permit quantitation by LC with fluorescence detection. The official AOAC TLC confirmation of identity method was used to confirm all positive samples with B1 concentrations &gt;0.04 ppb and M1 concentrations &gt;0.1 ppb. Sixty samples in the January group and 100 samples in the April group were assayed. Concentrations of aflatoxins B1 and M1 in the first group of pig livers ranged from 0.04 to 0.06 ppb. The identity of aflatoxin Bi was confirmed in all positive samples. Aflatoxin M1 could not be confirmed in any of the positive liver samples because the method was insufficiently sensitive for this aflatoxin. No positive muscle samples were found. In the second set, 9 positive livers were determined with B1 concentrations from 0.01 to 0.24 ppb and M1 concentrations from 0.03 to 0.44 ppb. Two samples contained M1 only. None of the corresponding muscle samples contained aflatoxins. Of the 12 positive samples, 5 were from Iowa, 4 from South Carolina, 2 from North Carolina, and 1 from Illinois. Aflatoxins were not detected in any of the samples from Texas or Virginia. One sample from North Carolina contained more than 0.5 ppb total aflatoxins. Blind recovery studies were conducted by including an artificially contaminated liver sample for every 6 samples assayed, and 1 uncontaminated liver sample for every 18 samples. Recoveries of aflatoxins B1, d , and M1 were 71.8%, 73.2%, and 69.8% respectively.
Enzymatic Determination of Free Glutamic Acid in Dried Soups and in Minced Sausages: NMKL1 Collaborative Study
Authors: Hattula M Tapani , Wallin Harriet C ,   Collaborators:, Andersen R , Blomberg K , Carlsson K , Hald B , Huge-Jensen E , Johansson M , Kari T , Larsen Krog L B , Loimaranta J , Yman I Malmheden , Nordbotten A , Reijonen M 
Published: February 2020

Abstract
An enzymatic method for the determination of free glutamic acid in meat products and dried soups was collaboratively studied in 11 laboratories. In the presence of the enzyme glutamate dehydrogenase, L-giutamic acid is oxidatively deaminated by nicotinamide adenine dinucleotide (NAD) to 2-oxoglutarate. In a reaction catalyzed by diaphorase, the NADH thus formed converts 2-(p-iodophenyl)-3-(p-nitrophenyl)-5-phenyltetrazolium chloride to a formazan, which is measured in the visible range at 492 nm. Fourteen samples (7 samples of minced sausage and 7 samples of dried cauliflower soup) with glutamate contents varying between 0.4 and 16 g/kg were included In the study. Materials were distributed to participants as blind duplicates and as split level pairs. The mean relative standard deviation (RSDR) for reproducibility for the dried soup material containing glutamate between 7 and 16 g/kg was 4.6%. RSDR values for samples of minced sausage containing glutamate at lower levels (0.4-1.3 g/kg) were between 12 and 16%.
Potassium as an Index of Fruit Content in Baby Food Products. Part I. Banana-Containing and Apricot-Containing Products
Authors: Harvey Robert A , Theuer Richard C 
Published: February 2020

Abstract
Percentage ingredient labeling has been proposed for baby foods. We determined whether or not the potassium content of baby foods could be used to verify the quantity of fruit when the characterizing ingredients were apricots or bananas, fruits rich in potassium. Official values for potassium in fruit (USDA Handbook No. 8-9) did not agree well with actual analyses. The potassium levels of products of known composition were accurately predicted from analyses of the actual ingredients used to make the foods. For banana-containing monofruit products of variable or unknown composition, potassium analysis led to fruit level estimates consistent with either the known composition or the label declaration. For products of unknown composition made with apricot concentrate, however, potassium analysis led to fruit level estimates lower than the probable fruit content. The quantity of fruit in baby foods made with potassium-rich fruits can be estimated from the potassium content if the potassium value for the fruit is representative of the actual ingredients used to make the product, if potassium analysis is to be used to verify compliance with percentage ingredient labeling, there must be statutory specification of the singlestrength fruit level for fruit reconstituted from concentrate.
Identification of Whale Species by Thin-Layer Isoelectric Focusing of Sarcoplasmic Proteins1
Authors: Ukishima Yoshiyuki , Kino Masahiko , Kubota Hiroyuki , Wada Shiro , Okada Shoji 
Published: February 2020

Abstract
Thin-layer isoelectric focusing was applied to the identification of whale (Cetacea) species by using water-soluble sarcoplasmic proteins of skeletal muscles. Twenty-eight samples consisting of 4 species (10 samples) of baleen whales (Mysticeti) and 8 species (18 samples) of toothed whales (Odontoceti) were analyzed. Each sample (approximately 1 g) was electrophoresed with Ampholine PAGplate, pH 3.5-9.5. The electrophoretic profiles were species-specific on the 4 toothed whale species that did not have a marked intra-species difference, and all 4 baleen whale species. However, the profiles were not specific on the 4 other dolphin species, even though they were discriminable from the other 4 toothed whale species. Numerical values of pls and relative peak heights were obtained by densitometric analysis of the isoelectro-focused protein bands. The bands were also species-specific for the 8 toothed whale species mentioned. The values may be applicable to species identification without the need for a standard sample, which may not be readily obtainable. Experiments on test samples of minke and sei whales showed that bloodletting with ice water made the densities of isoelectro-focused bands thinner, although species identification was still possible by using the Inside part of muscles. Heat treatment at below 60°C for 10 min caused little denaturation; at higher temperatures the protein bands were diminished in a temperature-dependent fashion. Therefore, the present isoelectric focusing analysis should be applicable to small samples of whale meat, excluding several species of dolphins.
Use of the Mycosep Multifunctional Cleanup Column for Liquid Chromatographic Determination of Aflatoxins in Agricultural Products
Authors: Wilson Thomas J , Romer Thomas R 
Published: February 2020

Abstract
A liquid chromatographic (LC) technique has been developed that uses the Mycosep™ multifunctional cleanup (MFC) column. MFC columns provide a rapid 1-step extract purification. They are designed to retain particular groups of compounds that may create Interferences in analytical methods. At the same time, MFC columns allow compounds of interest to pass through. In the method presented, test samples are extracted in a blender with acetonitrile-water (9 + 1). A portion of the extract is forced through an MFC column designed especially for analysis of numerous mycotoxins. Analytical interferences are retained, while aflatoxins pass through the column. Aflatoxins B1 and G1 are converted to their hemiacetals by heating a mixture of purified extract and water-trifluoroacetic acid-acetic acid (7 + 2 + 1) at 65°C for 8.5 min. An aliquot of this mixture is analyzed by isocratic LC with acetonitrile-water mobile phase and fluorescence detection. A detection limit of less than 0.5 ng/g for aflatoxin B1 was obtained. Average recoveries greater than 95% total aflatoxins (B1, B2, G1, and G2) and coefficients of variation of less than 3% were obtained. The method was successfully applied to the following commodities: com, almonds, pistachios, walnuts, peanuts, Brazil nuts, milo, rice, cottonseed, corn meal, corn gluten meal, fig paste, and mixed feeds.
Precolumn 𝘖-Phthalaldehyde Derivatization and Reversed-Phase Liquid Chromatography of S-Methylmethioninesulfonium in Satsuma Mandarin Juice
Authors: Sumitani Hidenobu , Suekane Sachiko , Sakai Yasue , Tatsuka Kiyoaki 
Published: February 2020

Abstract
Experiments were conducted to determine the amount of S-methylmethlonlnesulfonium (MMS) in Satsuma mandarin Juice using a precolumn 𝘖-phthalaldehyde (OPA) derivatization and reversedphase liquid chromatography. Favorable analytical conditions that allowed MMS analysis were achieved by using OPA/3-mercaptopropionlc acid (MPA) as a derivatization agent with fluorescence detection (excitation at 330 nm, emission at 450 nm). A C18 reversed-phase column with 5 μm particle size and a length of 250 mm was used. Resolution of MMS/OPA/MPA derivative was accomplished with a linear gradient eluent (30mM sodium acetate buffer solution, pH 7.3, and 70% (v/v) methanol). Quantitative analysis of MMS by the internal standard method using β-alanine gave highly reproducible result with a coefficient of variation less than 3%. Recovery of MMS added to Juice samples was 105%. MMS content in Satsuma mandarin Juice was 28.2μM.