Interference of Saturated Fats in the Determination of Low Levels of trans Fats (below 0.5%) by Infrared Spectroscopy

Consumption of Ashtanga Ghrita (clarified cow butter added with herb extracts) improves cognitive dysfunction induced by scopolamine in rats via regulation of acetylcholinesterase activity and oxidative stress

OBJECTIVES

Ashtanga Ghrita (AG), an Indian traditional formulation, has been used to promote neuropharmacological activities. AG is made up of clarified cow butter (ghee) and eight different herbs.

METHODS

To test whether scopolamine (SCP)-induced dementia and brain oxidative stress can be counteracted by AG, rats were separated into five groups (n=6/group): group one control, group two SCP (1 mg/kg b.w., i.p.) treated and group three to five were co-treated with different doses of AG (1.25, 2.5 and 5 g/kg b.w., orally) and SCP. After the treatment regimen, behavioral (Y-maze test) and brain biochemical changes were measured in all groups.

RESULTS

Microbial load and heavy metals were found within permissible limits. Results from attenuated total reflection Fourier-transform infrared spectroscopy demonstrated the complexation/interaction of herbal phytoconstituents with the functional groups of Ghrita. Preliminary phytochemical analysis of AG exhibited the occurrence of flavonoids, phenolics, glycosides, steroids, triterpenes, tannins, and amino acids. Findings of the experimental study exhibited that AG significantly protected the rats from SCP-induced behavioral dysfunction and brain biochemical alterations.

CONCLUSIONS

This study demonstrates that AG protects the brain from SCP-induced dementia by promoting brain antioxidant activity and thus could be a promising drug for the treatment of neurodegenerative disease.

Application of Mid-Infrared Portable Spectrometer for the Rapid Determination of Trans-Fatty Acid Content in Lipid Extracts of Snack and Bakery Products

In 2015, the US Food and Drug Administration passed a ban on the "generally recognized as safe" status of partially hydrogenated oils (PHOs), and in June 2018, PHOs were prohibited from being used. Our objective was to develop a predictive model to quantify trans-fat concentrations in bakery and snacks products using a portable mid-infrared (MIR) spectrometer. The approach was tested using 24 calibration standards (consisting of trielaidin in triolein and tripalmitin) and 87 bakery and snack products ranging from ND to 65% trans-fat. The fat was extracted by grinding products into powders and extracting the fat using petroleum ether. Gas Chromatography (AOCS Cd 14c-94) was used to determine the fatty acid profile and trans-fat content. Spectra were acquired by directly placing the fat (200 μL) onto the heated (65 ± 1°C) 5-reflection ZnSe crystal of a portable MIR spectrometer. Partial least squares regression (PLSR) models were developed using the calibration standards and extracted fats spectra targeting the signal of the C-H out-of-plane deformation band at 966 cm-1. Best model performances were obtained using the spectra of the extracted fat from bakery and snack products with the standard error of prediction of 0.5 g of trans-fats per 100 g of fat. We found that 25% of products labeled as zero trans-fat/serving did not comply with the maximum tolerance levels based on GC-FAME analysis. Portable FTIR devices operating in attenuated total reflection (ATR) mode can provide the food industry and government food inspectors with rapid, accurate, and high throughput measurements for routine screening to facilitate regulatory compliance.

Rapid Prediction of Low (<1%) trans Fat Content in Edible Oils and Fast Food Lipid Extracts by Infrared Spectroscopy and Partial Least Squares Regression

The United States Food and Drug Administration (FDA) ruled that partially hydrogenated oils (PHO), the major dietary source of industrially produced trans fat (TF), were no longer "generally recognized as safe (GRAS)" for any use in human food. Consequently, the objective of this study was to develop a rapid screening procedure using attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy in conjunction with partial least squares regression (PLSR) for the quantitative and accurate prediction of low concentrations of trans fatty acid (TFAs) (<1% of total fatty acids (FAs)). Broad-based calibration models were developed for a combined set of samples consisting of edible oils and fast food lipid extracts. Predicted concentrations of TFAs in the two matrices showed good correlation with the primary reference data generated by gas chromatography (GC) (R² > 0.99) and high accuracy as evidenced by low root-mean-square error of cross-validation (RMSECV) values. The lowest TFA concentration, determined by GC to be 0.13% of total FAs, was accurately predicted by ATR-FTIR/PLSR as 0.18% of total FAs. This simple, rapid ATR-FTIR/PLSR methodology has the potential for use as a screening alternative to conventional gas chromatographic methods for predicting the TFA content of edible oils and food lipid extracts for regulatory purposes and quality control of raw material and processed food.

PRACTICAL APPLICATIONS

FDA ruled that partially hydrogenated oils were no longer "generally recognized as safe (GRAS)" for any use in human food. Consequently, we have proposed a rapid screening procedure, based on infrared spectroscopy and chemometrics, to rapidly and accurately predict low concentrations of trans fatty acids (<1% of total fatty acids) in edible oils and food lipid extracts.

Comparison of two derivatization methods for the analysis of fatty acids and trans fatty acids in bakery products using gas chromatography

Two different procedures for the methylation of fatty acids (FAs) and trans fatty acids (TFAs) in food fats were compared using gas chromatography (GC-FID). The base-catalyzed followed by an acid-catalyzed method (KOCH3/HCl) and the base-catalyzed followed by (trimethylsilyl)diazomethane (TMS-DM) method were used to prepare FA methyl esters (FAMEs) from lipids extracted from food products. In general, both methods were suitable for the determination of cis/trans FAs. The correlation coefficients (r) between the methods were relatively small (ranging from 0.86 to 0.99) and had a high level of agreement for the most abundant FAs. The significant differences (P = 0.05) can be observed for unsaturated FAs (UFAs), specifically for TFAs. The results from the KOCH3/HCl method showed the lowest recovery values (%R) and higher variation (from 84% to 112%), especially for UFAs. The TMS-DM method had higher R values, less variation (from 90% to 106%), and more balance between variation and %RSD values in intraday and interday measurements (less than 4% and 6%, resp.) than the KOCH3/HCl method, except for C12:0, C14:0, and C18:0. Nevertheless, the KOCH3/HCl method required shorter time and was less expensive than the TMS-DM method which is more convenient for an accurate and thorough analysis of rich cis/trans UFA samples.

Evaluation of FT-NIR and ATR-FTIR spectroscopy techniques for determination of minor odd- and branched-chain saturated and trans unsaturated milk fatty acids

Determination of nutritionally important trans MUFA, CLA, and OBCFA milk fatty acids (often present in amounts lower than 1.0 g/100 g of total fat) using fast and nondestructive analytical methods would enhance their use as diagnostic tools in dairy herd and human health management. Here, PLS regression using ATR/FTIR spectra indicated potential for determination of trans-11 C18:1 and trans-12 C18:1 (Rcv² ≥ 0.80), and trans-9 C18:1 in very minor concentration (Rcv² > 0.82), as well as anteiso C15:0 (Rcv² = 0.57) and iso C17:0 (Rcv² = 0.61). Furthermore, the main cis-9,trans-11 CLA isomer was predicted well despite the high trans MUFA concentration. Differentiation between the CLA and the trans MUFA signals was evident (based on specific cis/trans bands), and branched-chain saturated fatty acid methyl esters revealed specific iso and anteiso ATR/FTIR absorbance bands. None of the minor FA PLS results with FT-NIR showed interesting potential, except satisfactory predictions for trans-9 C18:1 and cis-9,trans-11 CLA. Overall, ATR/FTIR resulted in better calibrations and provided more specific information for determination of minor milk fatty acids.

Selective Electrocatalytic Hydrogenation of Linolenic Acid onPd/Al2O3andPd-Co/Al2O3Catalysts

Electrochemical hydrogenation of linolenic acid as a model for polyunsaturated acids was studied on Pd and Pd/Al2O3catalysts in acidic and alkaline media. The results are presented in terms of number of double bonds in the polyunsaturated fatty acid and interpreted in terms of the adsorption capacity of the catalysts in these media. The highest hydrogenation yield was obtained with Pd/Al2O3at pH 13, in good correlation with the adsorption power of linolenic acid and its first hydrogenation product, linoleic acid, measured in this solution. A preliminary electrochemical hydrogenation study was conducted on Pd/Al2O3catalyst containing Co, in the optimum electrolysis conditions, showing a cooperative effect of the noble metals regarding thecis/transselectivity with preferential formation ofcis-oriented monounsaturated compound. All the products were characterized by gas chromatography after derivatization of the samples; fifteencis-transisomers of monounsaturated fatty acid which could be identified are presented here.