bluuebunny/crossref_metadata_2025_split huggingface dataset:
Liquid Chromatographic Determination of Safrole in Sassafras-Derived Herbal Products
Authors: Carlson Marvin , Thompson Richard 
Published: February 2020

Abstract
A liquid chromatographic (LC) method was developed for determining safrole in herbal products derived from sassafras (Sassafras albidumf as well as related compounds such as isosafrole and dihydrosafrole. The procedure involves solvent extraction and isolation of analyte by reversed-phase LC with UV detection at 235 nm. Safrole is resolved from related compounds and other sample constituents including thymol, a component of thyme. A linear concentration range of 0.003-0.200 mg/mL was obtained for safrole, isosafrole, and dihydrosafrole. Limits of detection (LOD) and quantitation (LOQ) were 0.0015 and 0.0051 μg/mL for safrole, 0.0018 and 0.0061 μg/mL for isosafrole, and 0.0038 and 0.0125 μg/mL for dihydrosafrole, respectively. Intraday relative standard deviations (RSDs) for safrole (n= 5) from various samples ranged from 1.30 to 5.39% at analyte levels of 0.01-1.5%. Safrole contents of 26 samples including root bark powder, leaves, oils, tea concentrate, herbal extract tinctures, and herbal powder capsules ranged from &lt;LOD for most leaf samples to 92.4% for an oil. Recoveries of safrole from fortified samples ranged from 83.6% for an oil to 117.2% for a tincture preparation. Safrole contents of 0.09-4.66 mg/cup were found for brewed teas prepared from sassafras root bark powders and tinctures.
Determination of β-Carotene in Commercial Foods: Interlaboratory Study
Authors: Schuep Willy , Schierle Joseph 
Published: February 2020

Abstract
Two sample preparation procedures for determination of total β-carotene and (all-)-β-carotene were tested in a collaborative study involving 14 laboratories and using 4 commercial products containing supplemented or natural β-carotene. One assay used classical sample preparation, consisting of saponification, extraction, washing, and drying ofthe extract and redissolution of residue for liquid chromatography (LC). The other assay used simple extraction without saponification. LC conditions were left for the analysts to decide as long as aclear separation of lycopene and ϑ-carotene from Bcarotene was achieved. Mean contents of test samples ranged from 0.3 to 18 mg/100 g for total β-carotene and from 0.2 to 16 mg/100 g for (all-)-β-carotene. Repeatability relative standard deviations (RSDr)for total B-carotene ranged from 2.9 to 5.6% and relative reproducibility standard deviation (RSDR) ranged from 6.5 to 15%. Corresponding values for(all-)-β-carotene were 3.3-5.1 % for RSDr and 8.4- 14% for RSDR. Excluding the (Z)-isomers from uantitation of β-carotene can result in significant underestimation of the effective β-carotene content especially if the LC systems used is high quality.
Application of Immunoaffinity Columns to Mycotoxin Analysis
Authors: Scott Peter M , Trucksess Mary W 
Published: February 2020

Abstract
Immunoaffinity columns (lACs) are widely used for cleanup and isolation of mycotoxins extracted from foods and biological fluids, particularly afla-toxins, ochratoxin A, and fumonisinsẳ The columns are prepared by binding antibodies specific for a given mycotoxin to a specially activated solid-phase support and packing the support suspended in aqueous buffer solution into a cartridge. The mycotoxin in the extract or fluid binds to the antibody, impurities are removed with water or aqueous solution, and then the mycotoxin is desorbed with a miscible solvent such as methanol. Further separation can be performed with lAC, followed by liquid chromatographic (LC) quantitation, either off-line or on-line in an automated system, or by fluorometryằ lACs have been used by laboratories that developed the antibodies but are also available commercially for aflatoxins, ochratoxin A, fumonis-ins, zearalenone, and deoxynivalenolễ Among commercial lACs, Aflatest P is used as the cleanup step in an LC method and in a solution fluorometry method for corn, peanuts, and peanut butter that was adopted as an AOAC INTERNATIONAL Official Method after evaluation by an international collaborative study. As part of a fluorometer-based test kit, aflatest P was further certified by the AOAC Research Institute to measure total aflatoxins in 10 grains and grain products. lACs can concentrate the analyte from a large amount of sample, allowing detection limits at low parts-per-trillion levels in some cases (e.g., for aflatoxin Mi and ochratoxin A in liquid food matrixes). Regeneration of lACs for reuse in aflatoxin, ochratoxin A, fumon-isin, and zearalenone analyses has been investigated.
Determination of Chromium in Feeds by Automated Microwave Digestion and Atomic Absorption Spectrophotometry
Authors: Gallo Pasquale , Serpe Luigi , Brambilla Gianfranco 
Published: February 2020

Abstract
Chromium, as trivalent organic form, has been recently proposed as feed additive to improve animal welfare and the quality-quantity of meat productions. To control its use in animal production we developed an analytical method that consisted of sample digestion by a commercially available focused microwave system and, subsequently, metal determination by graphite furnace atomic absorption spectrophotometry. The mineralization step was performed by treating the samples with a nitric acid-sulphuric acid-hydrogen peroxide mixture. Complete sample digestion was achieved in 26 min, as compared to 8-12 h or more required by dry ashing. To determine method accuracy and precision, we analyzed both feeds spiked at different Cr concentrations and a reference plant material. We found that mean metal recoveries ranged from 98.7 to 102.7% and for the reference material we obtained an excellent agreement between calculated and certified value. Quantitative Cr yields and relative coefficients of variation between 0.77 and 9.7% were very good and accounted for method accuracy and reliability. Finally, we applied the developed method to Cr analysis of some commercial feeds and the results were compared with those obtained by dry-ashing procedure.
Discrimination of Sound and Granary-Weevil-Larva-Infested Wheat Kernels by Near-Infrared Diffuse Reflectance Spectroscopy
Authors: Ghaedian Ahmad R , Wehling Randy L 
Published: February 2020

Abstract
Sound and infested wheat kernels containing lateinstar granary weevil larvae, as identified by X-ray analysis, were used to evaluate the ability of nearinfrared (NIR) spectroscopy to predict the presence of insect larvae in individual wheat kernels. Diffuse reflectance spectra at 1100-2500 nm were recorded from individual infested and sound kernels. Principal component analysis (PCA) of NIR spectra from sound kernels was used to construct calibration models by calculation of Mahalanobis distances. Calibration models were then applied to spectra obtainedfrom both sound and infested kernels in a separate validation set. A 5-factor PCA model using data from a first-derivative spectral transformation was the best model for correctly classifying kernels in an expanded validation sample set, including 100% of sound, 93% of infested, 95% of sound air dried, 86% of infested air dried kernels, and 90% of sound kernels from 6 wheat varieties. Calibrations using the spectral region from 1100 to 1900 nm were least sensitive to kernel moisture differences. Similar results were obtained when discriminant analysis was applied to log 1/R data from selected discrete wavelengths of NIR spectra.
Rapid Microbiological Methods with Hazard Analysis Critical Control Point
Authors: Griffiths Mansel W 
Published: February 2020

Abstract
The proactive approach to ensuring food safety termed hazard analysis critical control point (HACCP) was introduced in the 1960s by the Pillsbury Company, in collaboration with the U.S. Army Natick Laboratories and National Aeronautics and Space Administration, to help guarantee that astronauts would not be incapacitated by the trauma of foodborne illness during space flights. The approach has subsequently been adopted as the standard food safety management system worldwide and is seen as forming the basis for harmonization of food inspection regulations necessitated by trade agreements such as General Agreement on Tariffs and Trade and North American Free Trade Agreement as the move toward globalization of trade in food products gains momentum. The new U.S. Department of Agriculture Mega-Reg requires mandatory introduction of HACCP, and the Food Safety Enhancement Program of Agriculture and Agri-food Canada, as well as the “due diligence” legislation of the European Union, is centered on HACCP principles.
Comparison of Antibody-Direct Epifluorescent Filter Technique with the Most Probable Number Procedure for Rapid Enumeration of Listeria in Fresh Vegetables
Authors: Tortorello Mary L , Reineke Karl F , Stewart Diana S 
Published: February 2020

Abstract
The antibody-direct epifluorescent filter (Ab-DEFT) technique was evaluated as a rapid alternative to the most probable number (MPN) method for enumeration of artificially inoculated Listeria monocytogenes in ready-to-eat packaged salads and other fresh vegetables. Ab-DEFT was performed by homogenization of food in mesh-lined Stomacher bags, followed by prefiltration of homogenate through a 5 μm pore nylon filter, and passage of filtrate through a 0.4 μm pore black polycarbonate filter to collect and concentrate Listeria cells. After cells were stained with a fluorochrome-labeled polyclonal antibody to Listeria, the filter surface was examined by epifluorescence microscopy, and fluorescent cells were counted. A 3-tube MPN procedure was performed by successive enrichments of homogenized foods in Listeria enrichment and Fraser broths, followed by selective plating. Ab-DEFT provided quantitative determinations of Listeria cells that correlated with plate counts and MPN estimates in a linear response over a range of cell concentrations from 10 to 107 colony forming units (CFU)/mL. Microbial backgrounds as high as 108 CFU/mL did not affect performance of Ab-DEFT. In contrast to the MPN method, which required 5 days to perform, quantitation by Ab-DEFT could be completed in less than 1 h. Despite cross-reactivities demonstrated by the polyclonal fluorescent antibody, the potential of Ab-DEFT as a rapid alternative to MPN for microbial cell enumeration was evident.
Determination of Aflatoxins in Beer
Authors: Scott Peter M , Lawrence Guillaume A 
Published: February 2020

Abstract
Aflatoxins B1, B2, G1, and G2 were determined at parts-per-trillion levels in beer by immunoaffinity column cleanup and reversed-phase liquid chromatography (LC) with fluorescence detection after trifluoroacetic acid derivatization. Silanized vials were necessary for the evaporation step in order to obtain good recoveries of aflatoxins from spiked beer samples. Recoveries averaged 90–104%, 94%, 84–87%, and 89% for aflatoxins B1, B2, G1, and G2, respectively, at levels of 9.7–133 ng B1, 46 ng B2, 35–140 ng G1 and 41 ng G2/L. Detection limits were 19–20 ng/L for aflatoxins B1 and G1 and 15–16 ng/L for aflatoxins B2 and G2 (signal-to-noise ratio = 3:1) obtained by using an excitation wavelength of 360 nm; at 340 nm these detection limits were lowered to about 2 ng/L. Analysis of 24 beer samples, the majority from the United States and Mexico, showed natural contamination of one sample of Mexican beer at 49 ng B1/L when determined at 360 nm excitation, but reanalysis of 23 of the samples using 340 nm excitation indicated that an additional 4 Mexican samples and one Brazilian sample contained anatoxin B1 at low levels (&lt; 10 ng/L).
Determination of Lead in Wine by Graphite Furnace Atomic Absorption Spectrophotometry: Interlaboratory Study
Authors: Brereton Paul A , Robb Paul , Sargent Christine M , Crews Helen M , Wood Roger ,   Collaborators:, Caputi A , Carrington J , Chetaneau B , Cohen S , Davies R W , Davis W S , Dix E , Ennion; R A , Furniss S , Gardner J W , Griffin J , Hampton I , Harrison N , Heide C , Hollywood F , Hopkins J , Liddle P , Meagher J , Osborne P Y , Piatt T , Postlethwaite K , Procter J , Reynolds E B , Robinson J , Smith M , Sparkes S , Stangroom S G , Stevens R , Sutton P , Swain S , Turnbull J , Vidal J P , Waller J M , Zaiger K 
Published: February 2020

Abstract
An interlaboratory study of a graphite furnace atomic absorption spectrophotometry (GFAAS) method for the determination of lead in wine was conducted. Seventeen laboratories from France, United States, and the United Kingdom, using a variety of GFAAS instruments, took part in the study. The method incorporated a novel matrix-matching procedure to minimize matrix effects between standards and samples. Six wine test materials were prepared and sent to participants as 12 blind duplicate or split level samples. There was good agreement between results obtained from participants and target values (24–279 μg/L) obtained with an inductively coupled plasma-mass spectrometry method. The precision of the GFAAS method was well within the range predicted by the Horwitz equation for the 6 test materials analyzed. Repeatability standard deviations ranged from 3 to 17%. Reproducibility standard deviations were in the range of 10 to 30%. The method is recommended for use for official purposes.
Determination of Carbamate Insecticides in Apples, Pears, and Lettuce by LC with UV Detector
Authors: Minelli Elizabeth V , Angioni Alberto , Melis Marinella , Pirisi Filippo M , Cabras Paolo 
Published: February 2020

Abstract
A simple and rapid method was developed for determination of 8 carbamate insecticides and 10 of their metabolites in apples, pears, and lettuce by liquid chromatography with UV diode array detector. With this method no derivatization is needed. Carbamates not belonging to the N-methylcarbamate class and metabolites without the N-methyl group can also be determined.
Statistical Classification of Seafood Quality
Authors: Ellis P Christopher , Silva Mary Lou , Lee Chong M 
Published: February 2020

Abstract
Discriminant function analysis (DFA) was used to classify the freshness quality of lean fish, fatty fish, and shrimp as either acceptable (Class 1), marginal (Class 2), or unacceptable (Class 3). Fresh and frozen survey samples were statistically classified following an initial precategorization using sensory, chemical, and microbiological indices as predictor variables. Computer elimination of nonsignificant predictor tests, p &gt; 0.05, was used to optimize the test protocol. DFA correctly classified 98.5% of 67 preclassed lean fish samples (34 Class 1; 13 Class 2; 20 Class 3), 86.2% of 58 preclassed fatty fish samples (22 Class 1; 16 Class 2; 20 Class 3), and 98.7% of 79 preclassed shrimp samples (45 Class 1; 18 Class 2; 16 Class 3) by using all the quality indices. Computer selection of significant predictor indices at p &lt; 0.05 yielded correct predicted classifications of 95.5, 81.0, and 97.5%, respectively. The number of tests required to effectively categorize quality were reduced from 15 to 3 for lean fish, from 13 to 3 for fatty fish, and from 11 to 6 for shrimp, with minimal losses in prediction accuracy and a substantial reduction in analysis time.
A Precollaborative Study of Weight Determination Methods for Quick Frozen Shrimp
Authors: Fox Dobson Jane E , Mcclure Foster D , Rainosek Alvin P 
Published: February 2020

Abstract
A precollaborative study compared the accuracy and precision of official AOAC methods with other selected methods for determining net weight of IQF-glazed shrimp and block-glazed shrimp, assessed the ruggedness of the methods with respect to changes in the levels of the factors under study, and selected candidate methods for use in a collaborative study. Methods tested for determining deglazed (frozen) net weight of IQF-glazed shrimp were (1) AOAC Method 963.18 and (2) the Water Bath Dip Method. Methods tested for determining thawed net weight of IQF-glazed shrimp were (7) AOAC Method 967.13, (2) Modified AOAC Methodmnb 967.13, (3) Modified AOAC Methodpb 967.13, (4) the Codex Method, (5) the Air Thaw Method, and (6) Modified AOAC Method 963.18. The same methods except Modified AOAC Method 963.18 were tested for determining thawed net weight of block-glazed shrimp. A total of 864 0.45 kg (1 lb), 0.90 kg (2 lb), and 1.35 kg (3 lb) IQF-glazed shrimp test samples and 234 2.25 kg (5 lb) block-glazed shrimp test samples were collected. During sample preparation, test samples were subjected to either water with or without sodium tripolyphosphate (STP). During deglazing (IQF-glazed shrimp only) and/or thawing, test samples were allocated in a factorial design to assess the effects of STP presence (no STP and STP), sieve mesh sizes (2.83 and 2.38 mm; 0.11 and 0.09 in.), and sieve diameters (20 and 30 cm; 8 and 12 in.). During weighing, test samples werefurther allocated to a sequence of weighing procedures designed to assess the effects of using sieve weights (dry and wet) in combination with paper towel use (no and yes) and tared pan weights when calculating determined net weights. On the basis of the results of this precollaborative study, Modified AOAC Methodpb 967.13 and the Air Thaw Method seem to be the best methods to determine net weight of IQF-glazed and block-glazed shrimp. Therefore, to validate method choices in the collaborative study, the authors recommend analysis of IQF-glazed shrimp and block-glazed shrimp test samples, each prepared with or without STP, by Modified AOAC Methodpb 967.13 and the Air Thaw Method. To fulfill AOAC requirements, IQF-glazed shrimp and block-glazed shrimp test samples, each prepared with or without STP, must be analyzed by official methods: AOAC Method 963.18 (IQF-glazed shrimp only) and AOAC Method 967.13. During testing, sieve mesh size will be either 2.83 or 2.38 mm (0.11 or 0.09 in.), sieve diameter will be limited to 30 cm (12 in.), and weighing procedure will be limited to tared pan.
Cleanup Procedure for Monitoring Chlorinated Compounds in Animal Feed and Crops
Authors: Syhre Mona , Hanschmann Gudrun , Heber Ralf 
Published: February 2020

abstract
A powerful cleanup procedure for determination of chlorinated pesticides and poly chlorinated biphenyls (PCBs) in difficult agricultural matrixes like feeds or crops was developed to eliminate the interferences in chromatograms obtained by gas chromatography with electron capture detection. The adsorption material used was ENVI-Carb, a graphitized nonporous carbon material. This procedure proved to be more reliable than the established cleanup procedure, which uses gel permeation chromatography and silica gel cartridges. Because ENVI-Carb cleanup delivers clear, colorless eluates with no interferences, chlorinated pesticides and PCBs may be detected at levels as low as 0.0004 mg/kg for monitoring purposes. Accuracy was validated through a series of recovery experiments.
In Vitro Study of Nicotine Release from Smokeless Tobacco
Authors: Nasr Moheb M , Reepmeyer John C , Tang Yubing 
Published: February 2020

abstract
Four brands (Copenhagen Snuff, Skoal Bandit Classic, Skoal Wintergreen Long Cut, and Skoal Wintergreen Fine Cut) of smokeless tobacco products were tested for their rate of nicotine release into artificial saliva via direct contact or through a dialysis bag. Nicotine was determined by reversed-phase liquid chromatography. When samples were in direct contact with artificial saliva, most of the nicotine was released from the tobacco in the first minute. Nicotine release from Skoal Bandit Classic, marketed as smokeless tobacco in a sachet, was slower with the sachet intact than without the sachet. When smokeless tobacco and artificial saliva were placed inside a dialysis bag, nicotine release was much slower and primarily depended upon the permeability of the dialysis membrane. Although total nicotine was lowest for Skoal Bandit Classic, little difference was seen in nicotine release rates among the brands tested. When smokeless tobacco was placed in dialysis bags with artificial saliva outside, a significant difference was seen in rates of nicotine migration through the membrane. In this model, nicotine release from Copenhagen Snuff was much faster than from Skoal Bandit Classic with or without the sachet. This difference may be related to the pH of the smokeless tobacco products.
Protein Content of Wheat by Near-Infrared Spectroscopy of Whole Grain: Collaborative Study
Authors: Delwiche Stephen R , Pierce Richard O , Chung Okkyung K , Seabourn Bradford W ,   collaborators:, Baker L , Boyd T , Brenner c , Cain L , Chung E , Cohoef E , Delwiche S , Drapcho C , Flemm J , Gell A , Gerjets L , Gipson N , Guillemette R , Hughes R , Hurburgh C , Jackson C , Jessop D , Johnson D , Johnson D , Krouse R , LaCour C P , Lego M , Lewis V , Mbuvi S , McCaig T , Perbix K , Psotka J , Seabourn B 
Published: February 2020

abstract
A collaborative study was performed to assess accuracy, repeatability, and reproducibility of a nearinfrared (near-IR) method for determining crude protein content (PC) of whole-grain wheat. Four types of commercially available near-IR instruments, representing various combinations of wavelength region, mode of energy capture, method of energy dispersion, and treatment of spectral data, were used. Eight, 9,10, and 11 collaborators were involved, the exact number depending on instrument type. All collaborators received 22 samples of whole-grain hard red winter (HRW) wheat. They were furnished reference PCs (i.e., protein concentrations, w/w) corrected to a 12% moisture basis for instrument standardization. AOAC Method 990.03— combustion analysis—was the reference procedure. Standardization consisted of performing one of the following treatments to the instrument manufacturer's (or federal agency's) PC equation: (1) bias correction, (2) slope and intercept correction, or (3) recalibration with inclusion of standardization sample spectra. Standardized equations were then applied to a test set of 12 unknown HRW wheat sample spectra, with 2 samples blindly duplicated. The PCs of test samples ranged from 9 to 16%. Near-IR predictions were compared with reference measurements. Averaged within instrument type, root mean square of differences were 0.22, 0.24, 0.25, and 0.26% PC, depending on instrument. Corrected for bias within the test set, standard errors became 0.22, 0.18, 0.21, and 0.24% PC, respectively. These values were approximately twice the estimated lower limit for error (representing sample inhomogeneity). Overall repeatability relative standard deviation (RSD,) values were 0.92, 0.36, 0.42, and 0.74%, respectively. Overall reproducibility relative standard deviation (RSDR) values were 1.15, 0.61,1.53, and 1.38%. Such values for within-laboratory and between-laboratory variations of the near- IR methods were equivalent to values reported for the combustion method (990.03) for wheat. An inhouse study that examined all 6 U.S. wheat classes with one of the 4 instrument types produced repeatability and reproducibility values similar to those of the collaborative study, suggesting that the near-IR technique may be applied to red, white, hard, soft, and durum wheats. The near-IR method for determination of PC of whole-grain wheat has been adopted First Action (997.06) by AOAC INTERNATIONAL.