Joseph E. Jablonski

Reduction of fumonisin B1 in corn grits by single-screw extrusion.

This study was designed to determine the efficacy of extrusion in reducing fumonisin B1 in corn flaking grits in the presence and absence of glucose. In addition, degradation products of fumonisin B1 during extrusion were identified and quantitated with a mass balance approach. Uncontaminated clean corn grits, grits spiked with 30 microg/g fumonisin B1, and grits fermented with Fusarium verticillioides M-2552 (40-50 microg/g fumonisin B1) were extruded in the presence and absence of glucose (10%, w/w) using a single-screw extruder. Extrusion decreased fumonisin B1 by 21-37%, whereas the same process with added glucose further decreased fumonisin B1 by 77-87%. LC-fluorescence and LC-MS showed that most fumonisin in the extruded samples without added glucose was the fumonisin B1 form, whereas the main degradation product in grits extruded with glucose was N-(deoxy- d-fructos-1-yl)fumonisin B1. The formation of hydrolyzed fumonisin B1 was not significant during extrusion. Results suggest that extrusion in the presence of glucose may reduce fumonisin B1 in corn grits significantly.

Reduction of Fumonisin B1 in Corn Grits by Twin-Screw Extrusion

UNLABELLED This study was designed to investigate the fate of fumonisins in flaking corn grits during twin-screw extrusion by measuring fumonisin B₁ (FB₁) and its analogs with a mass balance approach. Food grade corn grits and 2 batches of grits contaminated with FB₁ at 10 and 50 μg/g by Fusarium verticillioides M-2552 were processed with or without glucose supplementation (10%, w/w) with a twin-screw extruder. Extrusion reduced FB₁ in contaminated grits by 64% to 72% without glucose and 89% to 94% with added glucose. In addition, extrusion alone resulted in 26% to 73% reduction in the levels of fumonisin B₂ and fumonisin B₃, while levels of both mycotoxins were reduced by >89% in extruded corn grits containing 10% glucose. Mass balance analysis showed that 38% to 46% of the FB₁ species detected in corn extruded with glucose was N-(deoxy-D-fructos-1-yl)-FB₁, while 23% to 37% of FB₁ species detected in extruded corn grits with and without added glucose was bound to the matrix. It was also found that the hydrolyzed form of FB₁ was a minor species in extruded corn grits with or without added glucose, representing <15% of the total FB₁ species present. Less than 46% of FB₁ originally present in corn grits could be detected in the fumonisin analogues measured in this study. Research is needed to identify the reaction products resulting from extrusion processing of fumonisin-contaminated corn products. PRACTICAL APPLICATION Twin-screw extrusion is widely used in food industry for its versatility. This technology may reduce the level of fumonisins in corn particularly with added glucose.

Nontargeted Detection of Adulteration of Skim Milk Powder with Foreign Proteins Using UHPLC–UV

Chromatographic profiles of skim milk powder (SMP) and mixtures of SMP with soy (SPI), pea (PPI), brown rice (BRP), and hydrolyzed wheat protein (HWPI) isolates were obtained by ultrahigh-performance liquid chromatography (UHPLC) with 215 nm detection. Two data analysis approaches were compared for their utility to classify samples as authentic or adulterated. The t test approach evaluated data points exceeding the 99% confidence limit of the mean authentic SMP chromatogram and used data points from the entire chromatogram. The other approach used the multivariate Q statistic from a SIMCA model of authentic samples to determine adulteration and used a selected retention window to obtain best classifications. Q-Statistic and t test correctly classified adulteration of SMP with SPI at the 1% and 3% levels, respectively, while minimizing false classifications of authentic SMP. Detection of SMP adulterated with PPI, BRP, and HWPI was possible at higher adulteration levels.

Exploring Authentic Skim and Nonfat Dry Milk Powder Variance for the Development of Nontargeted Adulterant Detection Methods Using Near-Infrared Spectroscopy and Chemometrics

A multinational collaborative team led by the U.S. Pharmacopeial Convention is currently investigating the potential of near-infrared (NIR) spectroscopy for nontargeted detection of adulterants in skim and nonfat dry milk powder. The development of a compendial method is challenged by the range of authentic or nonadulterated milk powders available worldwide. This paper investigates the sources of variance in 41 authentic bovine skim and nonfat milk powders as detected by NIR diffuse reflectance spectroscopy and chemometrics. Exploratory analysis by principal component analysis and varimax factor rotation revealed significant variance in authentic samples and highlighted outliers from a single manufacturer. Spectral preprocessing and outlier removal methods reduced ambient and measurement sources of variance, most likely linked to changes in moisture together with sampling, preparation, and presentation factors. Results indicate that significant chemical variance exists in different skim and nonfat milk powders that will likely affect the performance of adulterant detection methods by NIR spectroscopy.

Berry Fruits Modulated Endothelial Cell Migration and Angiogenesis via Phosphoinositide-3 Kinase/Protein Kinase B Pathway in Vitro in Endothelial Cells

Polyphenolic-rich berry fruits are known to activate redox-sensitive cellular signaling molecules such as phosphatidylinositol-3-kinase (PI3 kinase)/kinase B (Akt), resulting in a cascade of downstream signaling pathways. This study investigated the ability of strawberry (SB), wild blueberry (WBB), and cranberry (CB) extracts to induce the activation of PI3 kinase/Akt signaling in vitro in human umbilical endothelial cells (HUVECs) and whether this activation would enhance cell migration and angiogenesis. Anthocyanin profiles of the extracts were characterized using HPLC-ESI/MS, and Akt activation was investigated using the Alpha Screen SureFire assay. The total anthocyanin contents of SB, WBB, and CB extracts were 81.7, 82.5, and 83.0 mg/100 g fresh weight, respectively. SB, WBB, and CB extracts activated Akt in a dose-dependent manner via PI3 kinase and induced cell migration and angiogenesis in vitro in HUVECs. The results from this study suggest that polyphenolics in berry fruits may play a role in promoting vascular health.

Characterization of Near-Infrared Spectral Variance in the Authentication of Skim and Nonfat Dry Milk Powder Collection Using ANOVA-PCA, Pooled-ANOVA, and Partial Least-Squares Regression

Forty-one samples of skim milk powder (SMP) and nonfat dry milk (NFDM) from 8 suppliers, 13 production sites, and 3 processing temperatures were analyzed by NIR diffuse reflectance spectrometry over a period of 3 days. NIR reflectance spectra (1700–2500 nm) were converted to pseudoabsorbance and examined using (a) analysis of variance-principal component analysis (ANOVA-PCA), (b) pooled-ANOVA based on data submatrices, and (c) partial least-squares regression (PLSR) coupled with pooled-ANOVA. ANOVA-PCA score plots showed clear separation of the samples with respect to milk class (SMP or NFDM), day of analysis, production site, processing temperature, and individual samples. Pooled-ANOVA provided statistical levels of significance for the separation of the averages, some of which were many orders of magnitude below 10–3. PLSR showed that the correlation with Certificate of Analysis (COA) concentrations varied from a weak coefficient of determination (R2) of 0.32 for moisture to moderate R2 values of 0.61 for fat and 0.78 for protein for this multinational study. In this study, pooled-ANOVA was applied for the first time to PLS modeling and demonstrated that even though the calibration models may not be precise, the contribution of the protein peaks in the NIR spectra accounted for the largest proportion of the variation despite the inherent imprecision of the COA values.

RETRACTED: Phenolic composition, antioxidant properties, and endothelial cell function of red and white cranberry fruits

The effects of phenolic constituents in red cranberry extracts (RCE) and white cranberry extracts (WCE) on the endothelial cell function were investigated. Peonidin-3-O-galactoside, cyanidin-3-O-arabinoside, and cyanidin-3-O-galactoside were the predominant anthocyanins characterized, whereas a procyanidin tetramer was the predominant proanthocyanidin identified. The antioxidant properties of RCE and WCE were not significantly different regardless of antioxidant assays (DPPH, FRAP, and TEAC) used. Both RCE and WCE induced the phosphorylation of Akt in vitro in human umbilical endothelial cells (HUVEC), resulting in the phosphorylation of endothelial nitric oxide synthase, cell migration, and tube formation. The enhanced phosphorylation of PI3/Akt kinase in HUVEC, endothelial cell wound healing, and tube formation elicited by RCE and WCE suggest that overall phenolic constituents rather than individual phenolic compounds within the cranberry matrix may be responsible for these biological effects.

Effects of the Adulteration Technique on the Near-Infrared Detection of Melamine in Milk Powder

The United States Pharmacopeial Convention has led an international collaborative project to develop a toolbox of screening methods and reference standards for the detection of milk powder adulteration. During the development of adulterated milk powder reference standards, blending methods used to combine melamine and milk had unanticipated strong effects on the near-infrared (NIR) spectrum of melamine. The prominent absorbance band at 1468 nm of melamine was retained when it was dry-blended with skim milk powder but disappeared in wet-blended mixtures, where spray-dried milk powder samples were prepared from solution. Analyses using polarized light microscopy, Raman spectroscopy, dielectric relaxation spectroscopy, X-ray diffraction, and mass spectrometry indicated that wet blending promoted reversible and early Maillard reactions with lactose that are responsible for differences in melamine NIR spectra between wet- and dry-blended samples. Targeted detection estimates based solely on dry-blended reference standards are likely to overestimate NIR detection capabilities in wet-blended samples as a result of previously overlooked matrix effects arising from changes in melamine hydrogen-bonding status, covalent complexation with lactose, and the lower but more homogeneous melamine local concentration distribution produced in wet-blended samples. Techniques used to incorporate potential adulterants can determine the suitability of milk reference standards for use with rapid detection methods.

Targeted and non-targeted detection of lemon juice adulteration by LC-MS and chemometrics

ABSTRACT Economically motivated adulteration (EMA) of lemon juice was detected by LC-MS and principal component analysis (PCA). Twenty-two batches of freshly squeezed lemon juice were adulterated by adding an aqueous solution containing 5% citric acid and 6% sucrose to pure lemon juice to obtain 30%, 60% and 100% lemon juice samples. Their total titratable acidities, °Brix and pH values were measured, and then all the lemon juice samples were subject to LC-MS analysis. Concentrations of hesperidin and eriocitrin, major phenolic components of lemon juice, were quantified. The PCA score plots for LC-MS datasets were used to preview the classification of pure and adulterated lemon juice samples. Results showed a large inherent variability in the chemical properties among 22 batches of 100% lemon juice samples. Measurement or quantitation of one or several chemical properties (targeted detection) was not effective in detecting lemon juice adulteration. However, by using the LC-MS datasets, including both chromatographic and mass spectrometric information, 100% lemon juice samples were successfully differentiated from adulterated samples containing 30% lemon juice in the PCA score plot. LC-MS coupled with chemometric analysis can be a complement to existing methods for detecting juice adulteration.

High Throughput Quantification of Quaternary Ammonium Cations in Food Simulants by Flow-Injection Mass Spectrometry

Background: A flow-injection MS (FI/MS) method was evaluated for the quantitation of quaternary ammonium cations (QACs) in simple food simulants. Methods: The calibration standard was dimethyldioctadecyl ammonium ion (C18-C18), and the internal standard was benzyldimethylhexadecyl (BDMHD) ammonium ion. Calibration standards based on the C18-C18 ion were prepared in ethanol with a range of 5 to 500 ppb and contained 100 ppb BDMHD. The mobile phase was 90 + 10 (v/v) acetonitrile-5 mM aqueous ammonium acetate and flowed directly into an electrospray source of the mass spectrometer. Detection was accomplished by single ion recording (SIR) in positive mode. Results: Calibration curves were linear with coefficients of determination above 0.995, and the LOQ was 5 ppb. Recoveries of four QACs derived from Arquad 2HT-75, a commercially available surfactant, were measured in common food simulants: ethanol, water, 10% (v/v) ethanol in water, and 3% (v/v) aqueous acetic acid. A solvent exchange procedure was employed for the three aqueous solvents, which included complete evaporation of the sample followed by reconstitution in ethanol prior to injection. The solvent exchange method minimized losses because of QAC adsorption on glass surfaces. Recoveries ranged from 74.4 ± 4.0 to 106.7 ± 6.6% for the two most abundant Arquad 2HT-75 component cations, dimethyldioctadecyl ammonium and dimethyloctadecyl-hexadecyl ammonium. Conclusions: This method is suitable to quantify trace levels of QACs in food simulants as part of exposure evaluations related to their use in emerging food contact materials.