Application of Fourier transform infrared spectroscopy for the quality and safety analysis of fats and oils: A review

Macro- and Microelement Composition, Antioxidant Activity, and Biological Effect of Cold-Pressed Edible Oils from Commercial and Amateur Companies

The aim of this study was to examine cold-pressed oils available on the Polish market derived from different plants and manufacturers in the context of their biological activity, including micro- and macroelements, antioxidant properties, antimicrobial activity, and selected effects on eukaryotic cells. In total, 76 oil samples of 34 selected oil types from nine Polish companies (five commercial and four amateur) were tested. The content of macro- and micronutrients was assessed using ICP-OES, the level of fatty acid unsaturation was examined using Fourier transform infrared spectroscopy (FTIR), and total antioxidant potential (TAP) was assessed using the DPPH method. The antimicrobial activity of the selected oils against Gram-positive and Gram-negative bacteria, as well as fungi, representing both pathogens and human microbiota, was tested using the broth microdilution method. The MTT reduction assay was used to exclude the cytotoxic effect of the oils on the human fibroblast line HFF-1. It has been concluded that the composition of cold-pressed oils varied significantly depending on the plant used and the manufacturer. The total content of the elements tested ranged from 172.91 mg/kg in Helianthus annuus oil to 1580.73 mg/kg in Silybum marianum oil. The iron concentration limits were exceeded in 10 oils, the copper concentration limits were exceeded in 34 oils, and the lead concentration limits were exceeded in 18 oils. At least one of these elements was exceeded in 40 oils (53% of the tested samples), which is why testing the concentration of elements should be a standard procedure for assessing the quality of cold-pressed oils. There was no statistically significant correlation between the content of any macro- and microelements and TAP. While TAP was strongly correlated with the spectral unsaturation index of the oils, this relationship can be used to develop a simple and rapid assessment of oils quality. The strongest antioxidant activity (over 90%) was observed for Nigella sativa oils. Interestingly, among all the tested oils, only these from Nigella sativa L., whatever the producer, possessed also strong antimicrobial activity. None of the tested oils showed cytotoxicity against eukaryotic cells, so the cold-pressed oils can be considered safe.

The application of emerging technologies for the quality and safety evaluation of oilseeds and edible oils

Oilseeds and edible oils are an indispensable part for the human diet and provide nutritional support for the human health. It has been reported a total of above 170 million tons per annum of edible oils consumption were consumed worldwide. Safety and quality of oilseeds and edible oils cannot be ignored, which can pose risk to human health and cause agro-economic loss. Classical techniques widely used to detect the safety and quality attributes of oilseeds and edible oils often involve time-consuming and tedious operation; therefore, the development of low cost, rapid and non-destructive detection method is necessary. This review presents applications of four emerging spectroscopic techniques in recent ten years, such as Raman spectroscopy, fluorescence spectroscopy, fourier transform infrared spectroscopy and near-infrared spectroscopy for determining the quality and safety of oilseeds and edible oils. Meanwhile, the technical challenges and future prospects of these non-destructive spectroscopic technologies are also discussed.

Advanced analytical techniques for authenticity identification and quality evaluation in Essential oils: A review

Essential oils (EO), secondary metabolites of plants are fragrant oily liquids with antibacterial, antiviral, anti-inflammatory, anti-allergic, and antioxidant effects. They are widely applied in food, medicine, cosmetics, and other fields. However, the quality of EOs remain uncertain owing to their high volatility and susceptibility to oxidation, influenced by factors such as the harvesting season, extraction, and separation techniques. Additionally, the huge economic value of EOs has led to a market marked by widespread and varied adulteration, making the assessment of their quality challenging. Therefore, developing simple, quick, and effective identification techniques for EOs is essential. This review comprehensively summarizes the techniques for assessing EO quality and identifying adulteration. It covers sensory evaluation, physical and chemical property evaluation, and chemical composition analysis, which are widely used and of great significance for the quality evaluation and adulteration detection of EOs.

Enhanced cold plasma hydrogenation with glycerol as hydrogen source for production of trans-fat-free margarine

The quest for better nutritious foods has encouraged novel scientific investigations to find trans-fat reduction methods. This research proposes an innovative approach for the production of healthier trans-fat-free margarine from palm oil by the use of dielectric barrier discharge (DBD) plasma technology with glycerol serving as the principal source of hydrogen. The effectiveness of DBD plasma in hydrogenating palm olein was investigated. By employing a methodical series of experiments and thorough analytical approaches, examination of the saturated fatty acid conversion experienced its iodine value (IV) reduction from 67.16 ± 0.70 to 31.61 ± 1.10 under the optimal process parameters of 1 L min-1 He flow rate, 35 W plasma discharge power, 10 mm gap size, ambient initial temperature, and 12 h reaction time with solid texture. According to the method for producing trans-fat-free margarine in the absence of a catalyst and H2 gas, the hydrogenation rate of the prepared mixture of palm olein-glycerol was remarkably improved; the trans-fat content in the produced product was zero; the efficacy of incorporating cis- and trans-isomerization was lowered, and the method has a promising industrial application prospect.

Investigation into the Reduction of Palm Oil in Foods by Blended Vegetable Oils through Response Surface Methodology and Oxidative Stability Tests

Recently, there has been a significant transition in the dietary preferences of consumers toward foods containing health-promoting compounds. In addition, as people's environmental awareness increases, they are increasingly looking for sustainable solutions. Palm oil, an oil used extensively by the food industry, does not fit these criteria. This study investigated the development of a complex oil blend consisting of commonly used vegetable oils such as corn, rapeseed, sunflower, and palm oil. The aim was to find the optimal blended oil and compare this combination with palm oil in terms of its oxidative stability, antioxidant capacity, and the composition of bioactive compounds (i.e., fatty acids, tocopherols, and carotenoids). Palm oil was found to have greater oxidative stability as a result of its increased concentration of saturated fatty acids. The optimal blended oil, which consisted of corn and rapeseed oil at a ratio of 4:3 w/w, inhibited the superior antioxidant activity, showing a ~33% increase in DPPH• inhibition activity. ATR-FTIR spectra further verified the existence of a significant quantity of saturated fatty acids in palm oil and unsaturated fatty acids in the blended oil. Finally, several correlation analyses revealed interesting connections between oil samples and investigated parameters. This work has the potential to establish a basis for the mass production of oil blends that possess high concentrations of antioxidant compounds and reduce the use of palm oil.

Estimation of Proximate Composition in Rice Using ATR-FTIR Spectroscopy and Chemometrics

This study presents an innovative approach for estimating the proximate composition of diverse rice varieties using attenuated total reflectance fourier transform infrared (ATR-FTIR) spectroscopy and chemometric techniques. Principal component analysis (PCA) reveals distinct separations among the seven rice varieties based on their FTIR spectra. Robust partial least squares (PLS) regression models, developed with high calibration (R 2) values from 0.778 for protein up to 0.941 for moisture, demonstrate high accuracy in predicting proximate composition. The root mean squared error (RMSE) in percentage values, indicative of prediction accuracy, were low across all proximate components. To ensure the response variable of regression, proximate composition measurements were taken five times, while FTIR spectra were scanned tens of times, employing random numbers around the average with the same standard deviation as the measurement. Notably, the study emphasizes the pivotal role of the amide-III band in protein determination, alongside specific wavenumber regions associated with molecular changes in proximate components. This research underscores the potential of ATR-FTIR spectroscopy and chemometrics for rapid and accurate proximate assessment in food science and agriculture.

Novel oxidation indicator films based on natural pigments and corn starch/carboxymethyl cellulose

The existing oil oxidation detection methods are unsuitable for consumers to identify oil oxidation in a domestic setting. This study aims to develop indicator films detecting the degree of lipid oxidation with the naked eye. Purple sweet potato pigment (PSP) was chosen as a color indicator due to its response to hydrogen peroxide. The novel oxidation indicator films were prepared using corn starch, carboxymethyl cellulose (CMC), and varying concentrations of PSP. Fourier transform infrared spectroscopy spectra and scanning electron microscopy analysis confirmed the successful dispersion of PSP in the films. Thermal stability, light resistance, ultraviolet light resistance, mechanical resistance, and flexibility of films containing PSP were improved, enhancing the potential application in detecting oxidized substances. All the films exhibited noticeable color changes when exposed to different concentrations of hydrogen peroxide. These differences were more pronounced with higher levels of PSP. When these films were used to determine the degree of lipid oxidation, the ∆E value of the CS-PSP-0.25 % film showed a linear relationship (R2 = 0.929) with the peroxide value, unlike other films. Therefore, it is reliable to infer the peroxide value of edible oil by observing the color of the films, which helps customers avoid consuming expired oils.

Research on the Impact of Deep Eutectic Solvent and Hot-Water Extraction Methods on the Structure of Polygonatum sibiricum Polysaccharides

Deep eutectic solvent (DES) and hot-water extraction (HWE) methods were utilized to extract polysaccharides from Polygonatum sibiricum, referred to as DPsP and WPsP, respectively. The extracted polysaccharides were purified using the Superdex-200 dextran gel purification system, resulting in three components for each type of polysaccharide. The structures of these components were characterized. The molecular weight analysis revealed that DPsP components had slightly larger molecular weights compared with WPsP, with DPsP-A showing a slightly higher dispersity index and broader molecular weight distribution. The main monosaccharide components of both DPsP and WPsP were mannose and glucose, while DPsP exhibited a slightly greater variety of sugar components compared with WPsP. FTIR analysis demonstrated characteristic polysaccharide absorption peaks in all six PSP components, with a predominance of acidic pyranose sugars. NMR analysis revealed the presence of pyranose sugars, including rhamnose and sugar aldehyde acids, in both DPsP-B and WPsP-A. DPsP-B primarily exhibited β-type glycosidic linkages, while WPsP-A predominantly displayed α-type glycosidic linkages, with a smaller fraction being β-type. These findings indicated differences in monosaccharide composition and structure between PSPs extracted using different methods. Overall, this study provided experimental evidence for future research on the structure-function relationship of PSPs.

D2O assisted FTIR spectroscopic analysis of moisture in edible oil

D₂O-assisted moisture analysis of edible oils was investigated. The acetonitrile extract of the oil samples was split into two parts. The spectrum of one part was taken as is, another was recorded after addition of excess D₂O. Changes in spectral absorption of the H-O-H bending band (1600-1660 cm^-1) was used to calculate moisture in oil samples. To effectively depleting absorption of water in the acetonitrile extract, a 30-fold excess of D₂O is required. The typical OH-containing constituents in oil did not show significant interference on the H/D exchange. Validation experiments by using five oils with five levels of moisture spiked (50-1000 μg/g) suggested that the prediction tracked the spiked amounts well. The results of variance analysis indicate that there is no difference in terms of analytical methods and oil types used (p < 0.001). The D₂O method developed is generally applicable to the accurate analysis of moisture at trace levels (<100 μg/g) in edible oils.

New research development on trans fatty acids in food: Biological effects, analytical methods, formation mechanism, and mitigating measures

The trans fatty acids (TFAs) in food are mainly generated from the ruminant animals (meat and milk) and processed oil or oil products. Excessive intake of TFAs (>1% of total energy intake) caused more than 500,000 deaths from coronary heart disease and increased heart disease risk by 21% and mortality by 28% around the world annually, which will be eliminated in industrially-produced trans fat from the global food supply by 2023. Herein, we aim to provide a comprehensive overview of the biological effects, analytical methods, formation and mitigation measures of TFAs in food. Especially, the research progress on the rapid, easy-to-use, and newly validated analytical methods, new formation mechanism, kinetics, possible mitigation mechanism, and new or improved mitigation measures are highlighted. We also offer perspectives on the challenges, opportunities, and new directions for future development, which will contribute to the advances in TFAs research.

Adoption of analytical technologies for verification of authenticity of halal foods - a review

Halal authentication has become essential in the food industry to ensure food is free from any prohibited ingredients according to Islamic law. Diversification of food origin and adulteration issues have raised concerns among Muslim consumers. Therefore, verification of food constituents and their quality is paramount. From conventional methods based on physical and chemical properties, various diagnostic methods have emerged relying on protein or DNA measurements. Protein-based methods that have been used in halal detection including electrophoresis, chromatographic-based methods, molecular spectroscopy and immunoassays. Polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) are DNA-based techniques that possess better accuracy and sensitivity. Biosensors are miniatured devices that operate by converting biochemical signals into a measurable quantity. CRISPR-Cas is one of the latest novel emerging nucleic acid detection tools in halal food analysis as well as quantification of stable isotopes method for identification of animal species. Within this context, this review provides an overview of the various techniques in halal detection along with their advantages and limitations. The future trend and growth of detection technologies are also discussed in this review.

Effects of Ligustrum robustum (Rxob.) Blume extract on the quality of peanut and palm oils during storage and frying process

The potential uses of Ligustrum robustum (Rxob.) Blume extract as a natural antioxidant to protect the quality of different oils during storage and frying process were studied. The results showed that L. robustum extract has been shown to retard the decline in the quality of both oils based on the tests of acid value, peroxide value, p-anisidine value, color, volatile flavor, and fatty acid compositions, and the protective effect of L. robustum extract on the quality of peanut oil was better than that of palm oil. By the component analysis, L. robustum extract was found to have a total phenols content of 140.75 ± 1.52 mg/g, and ligurobustoside C was identified as the main phenolic compound. The thermogravimetric and differential scanning calorimetry results showed that L. robustum extract enhanced the oxidative stability of peanut and palm oils. In addition, Fourier transform infrared results indicated that L. robustum extract had protective effects on the C=C bond and ester bond of oil molecule. Moreover, by using electron spin resonance technique, L. robustum extract showed the ability to inhibit and scavenge alkyl-free radicals in both oils. The present results suggested that L. robustum extract may protect the quality of oils during the storage and frying process by inhibiting the oxidation of unsaturated fatty acids and might be a potential natural antioxidant in the food industry. PRACTICAL APPLICATIONS: The excellent antioxidant ability of Ligustrum robustum (Rxob.) Blume extract on the oxidation of different oils and its low price indicated that it could be used as a new low-cost natural antioxidant in oil processing.

Determination of Drugs in Clinical Trials: Current Status and Outlook

All pharmaceutical drugs, vaccines, cosmetic products, and many medical breakthroughs must first be approved through clinical research and trials before advancing to standard practice or entering the marketplace. Clinical trials are sets of tests that are required to determine the safety and efficacy of pharmaceutical compounds, drugs, and treatments. There is one pre-phase and four main clinical phase requirements that every drug must pass to obtain final approval. Analytical techniques play a unique role in clinical trials for measuring the concentrations of pharmaceutical compounds in biological matrices and monitoring the conditions of patients (or volunteers) during various clinical phases. This review focuses on recent analytical methods that are employed to determine the concentrations of drugs and medications in biological matrices, including whole blood, plasma, urine, and breast milk. Four primary analytical techniques (extraction, spectroscopy, chromatography, and electrochemical) are discussed, and their advantages and limitations are assessed. Subsequent to a survey of evidence and results, it is clear that microelectromechanical system (MEMS) based electrochemical sensor and biosensor technologies exhibit several notable advantages over other analytical methods, and their future prospects are discussed.

Going green: Development of a sustainable lipid-based enteric coating formulation for low-dose aspirin multiparticulate systems

There is a rising awareness of pharmaceutical industry of both patient-centric and sustainable product development. Manufacturing of multiparticulate systems (MPS) with functional coating via solvent-free hot melt coating (HMC) can fulfill both requirements. An innovative lipid-based formulation was developed with the composition of palmitic acid and Grindsted® citrem BC-FS (BC-FS) for enteric coating of acetylsalicylic acid (ASA). The ASA crystals were directly hot melt coated to produce user-friendly low-dose ASA MPS for thromboembolism prophylaxis. Prior to HMC, rational boundaries for the process temperature were defined based on the melting and crystallization behavior of coating blend. Stability of coating in terms of resistance to heat stress and solidstate stability were screened via Fourier-transform infrared spectroscopy and x-ray diffraction. Exposure of coating blend to 100 °C for two hours did not cause any chemical degradation. Crystal growth of palmitic acid and polymorphic transformation in BC-FS were observed after storage under accelerated conditions, however did not significantly affect the ASA release from coating. The developed formulation is a unique solvent-free, lipid-based enteric composition and paves the way for sustainable green pharmaceutical manufacturing.

Mechanism, indexes, methods, challenges, and perspectives of edible oil oxidation analysis

Edible oils are indispensable food components, because they are used for cooking or frying. However, during processing, transport, storage, and consumption, edible oils are susceptible to oxidation, during which various primary and secondary oxidative products are generated. These products may reduce the nutritional value and safety of edible oils and even harm human health. Therefore, analyzing the oxidation of edible oil is essential to ensure the quality and safety of oil. Oxidation is a complex process with various oxidative products, and the content of these products can be evaluated by corresponding indexes. According to the structure and properties of the oxidative products, analytical methods have been employed to quantify these products to analyze the oxidation of oil. Combined with proper chemometric analytical methods, qualitative identification has been performed to discriminate oxidized and nonoxidized oils. Oxidative products are complex and diverse. Thus, proper indexes and analytical methods should be selected depending on specific research objectives. Expanding the mechanism of the correspondence between oxidative products and analytical methods is crucial. The underlying mechanism, conventional indexes, and applications of analytical methods are summarized in this review. The challenges and perspectives for future applications of several methods in determining oxidation are also discussed. This review may serve as a reference in the selection, establishment, and improvement of methods for analyzing the oxidation of edible oil. HighlightsThe mechanism of edible oil oxidation analysis was elaborated.Conventional oxidation indexes and their limited values were discussed.Analytical methods for the determination of oxidative products and qualitative identification of oxidized and non-oxidized oils were reviewed.

Detection and quantification of palmolein and palm kernel oil added as adulterant in coconut oil based on triacylglycerol profile

Economically motivated adulteration of expensive coconut oil with low cost oil, like palm kernel oil and palmolein is difficult to detect and quantify by available methods primarily due to their overlapping physicochemical properties with coconut oil. In the present work, a HPLC method has been developed to detect and quantify the degree of adulteration of coconut oil with palmolein and palm kernel oil based on triglyceride structure. The normalized area percentage of trilaurin (C36) among the three major TAG molecular species dilaurin-monocaprin/myristin-caprylin-laurin (C34), trilaurin (C36) and dilaurin-monomyristin (C38) of coconut oil was chosen as detection index for quantifying degree of adulteration of coconut oil with palm kernel oil, while the area ratio of dipalmitoyl-monoolein: trilaurin was chosen as detection index for quantifying adulteration of coconut oil with palmolein. The RP-HPLC based method developed in the present work is effective with a 2-4% minimum detection limit of adulterant oils and 78-98% detection accuracy depending on the degree of adulteration and types of oil.

Effect of steaming process on the structural characteristics and antioxidant activities of polysaccharides from Polygonatum sibiricum rhizomes

Polygonatum sibiricum (P. sibiricum) rhizomes are widely used as a tonic and functional food, and are often processed to enhance their tonic function by repeated steaming and drying. As the most important constituent, the polysaccharide from P. sibiricum rhizomes (PSP) has demonstrated various activities, but the alteration of structural characteristics and activities of the purified PSPs during steaming process was rarely investigated. To well understand the effect of steaming process on the polysaccharides of P. sibiricum, neutral polysaccharides from P. sibiricum rhizomes (PSP0 ~ PSP9) after steaming were first isolated and purified, and then the chemical properties and antioxidant activities were determined. The results showed that the molar ratios of monosaccharides in PSPs were different. The molecular weights of PSPs were increased significantly after the fourth steaming. Morphological studies showed that the surface of PSPs became much tighter during the steaming process. Fourier transform infrared spectroscopy spectra displayed the polysaccharides had similar backbones and chemical groups. Furthermore, the antioxidant activity of PSPs was measured through radical scavenging tests. It was found that the radical scavenging activity of PSPs was elevated strikingly after steaming, and increased gradually with numbers of steaming process. The biological and chemical variance of PSPs revealed considerable segregation of PSP0, PSP1 ~ PSP4 and PSP5 ~ PSP9. In conclusion, our results proposed the fourth time as the optimal number of steaming to extract functional polysaccharide from P. sibiricum rhizomes.

ATR-FTIR-MIR Spectrometry and Pattern Recognition of Bioactive Volatiles in Oily versus Microencapsulated Food Supplements: Authenticity, Quality, and Stability

Fourier transform infrared spectroscopy on the middle infrared region (ATR-FTIR-MIR) proved to be a convenient and reliable technique to evaluate foods' quality and authenticity. Plants' essential oils are bioactive mixtures used as such or in different oily or microencapsulated formulations, beneficial to human health. Six essential oils (thyme, oregano, juniperus, tea tree, clove, and cinnamon) were introduced in three oily formulations (Biomicin, Biomicin Forte, and Biomicin urinary) and these formulations were microencapsulated on fructose and maltodextrin matrices. To study their stability, the microencapsulated powders were kept under light irradiation for 14 days at 25 °C or introduced in biopolymer capsules. All variants were analysed by ATR-FTIR-MIR, recording wavenumbers and peak intensities (3600-650 cm^-1). The data were processed by Unscrambler and Metaboanalyst software, with specific algorithms (PCA, PLSDA, heatmaps, and random forest analysis). The results demonstrated that ATR-FTIR-MIR can be successfully applied for fingerprinting and finding essential oil biomarkers as well as to recognize this pattern in final microencapsulated food supplements. This study offers an improved ATR-FTIR-MIR procedure coupled with an adequate chemometric analysis and accurate data interpretation, to be applied for the evaluation of authenticity, quality, traceability, and stability during storage of essential oils incorporated in different matrices.

The formation, determination and health implications of polar compounds in edible oils: Current status, challenges and perspectives

To effectively control the quality of edible oil, polar compounds in edible oils have been studied extensively in the past few decades, particularly in the field of frying. This article critically reviews the formation, determination, and health implications of the polar compounds in edible oils via comprehensive literature research. The challenges and perspectives of polar compounds in edible oils are also discussed. Three chemical reactions, including oxidation, hydrolysis, and polymerization, elaborate polar compound formation. Many techniques are used to determine the total polar compound content of edible oils, with comparative analysis; Fourier transform infrared technique is a relatively ideal method. A major obstacle for nutritional studies focused on polar compounds formed during frying is that few pure compounds have been quantified. To inhibit the formation of the polar compounds effectively, investigations into the applications of enzymatic method in developing new lipophilized antioxidants may be a new direction in research.

An overview of recent advances and applications of FT-IR spectroscopy for quality, authenticity, and adulteration detection in edible oils

Authenticity and adulteration detection are primary concerns of various stakeholders, such as researchers, consumers, manufacturers, traders, and regulatory agencies. Traditional approaches for authenticity and adulteration detection in edible oils are time-consuming, complicated, laborious, and expensive; they require technical skills when interpreting the data. Over the last several years, much effort has been spent in academia and industry on developing vibrational spectroscopic techniques for quality, authenticity, and adulteration detection in edible oils. Among them, Fourier transforms infrared (FT-IR) spectroscopy has gained enormous attention as a green analytical technique for the rapid monitoring quality of edible oils at all stages of production and for detecting and quantifying adulteration and authenticity in edible oils. The technique has several benefits such as rapid, precise, inexpensive, and multi-analytical; hence, several parameters can be predicted simultaneously from the same spectrum. Associated with chemometrics, the technique has been successfully implemented for the rapid detection of adulteration and authenticity in edible oils. After presenting the fundamentals, the latest research outcomes in the last 10 years on quality, authenticity, and adulteration detection in edible oils using FT-IR spectroscopy will be highlighted and described in this review. Additionally, opportunities, challenges, and future trends of FT-IR spectroscopy will also be discussed.

Differences in phosphatidylcholine profiles and identification of characteristic phosphatidylcholine molecules in meat animal species and meat cut locations

Phosphatidylcholine (PC) is an essential component of the plasma membrane. Its profile varies with species and tissues. However, the PC profiles in meat have not been explored in depth. This study aimed to investigate the differences in PC profiles between various meat animal species and meat cut sites, along with the identification of characteristic PC molecules. The results demonstrated that the PC profiles of chicken meat differed from those of other species. Significant differences were also observed between the PC profiles of pork meat and the meat obtained from other species. The amount of PCs containing ether bonds was high in pork meat. PCs containing an odd number of carbon atoms were characteristic of beef and lamb meats. Furthermore, PC profiles differed based on the muscle location in chicken and pork. These results suggest that the PC profiles of skeletal muscles are indicators of animal species and muscle location.

Analytical methods for determining the peroxide value of edible oils: A mini-review

Edible oils are prone to oxidation during processing and storage that may negatively affect the oil quality and human health. Determining the peroxide value (PV) of edible oils is essential because PV is one of the most typically used quality parameters to monitor lipid oxidation and control oil quality. Many approaches have been developed to determine the PV of oils. Among them, iodometric titration is the commonly used method for PV determination. Considering the limitations related to titrimetric methods, such as time and environmental concerns, several instrumental techniques have been considered as reliable alternatives. The advantages and limitations of classical titration and instrumental methods are summarized in this review. The prospects and reformative aspects for the future applications of these approaches in PV determination are also discussed.

Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR) Coupled with Chemometrics, to Control the Botanical Authenticity and Quality of Cold-Pressed Functional Oils Commercialized in Romania

Attenuated total reflectance-Fourier transform infrared ppectroscopy (ATR-FTIR) proved to be a reliable, rapid, and easy-to-use technique to evaluate vegetable oils quality and authenticity. The spectral range of the middle infrared region (MIR) of FTIR spectra, from 4000 to 600 cm−1, has been commonly used to fingerprint specific functional groups of lipids and their modified forms induced by oxidation of thermal treatment. The applicability of FTIR-MIR spectroscopy in assessing oil fingerprinting and quality parameters is crucially dependent on the chemometric methods, including calibrations with authentic samples. We report here the evaluation of seven types of cold-pressed functional oils (sunflower, pumpkin, hempseed, soybean, walnut, linseed, sea buckthorn) produced in Romania, provided directly from small enterprises (as genuine, process-controlled authentic samples) comparative to commercialized samples. Concomitantly, olive oils of similar claimed quality were investigated. The ATR-FTIR-MIR data were complemented by UV–Vis spectral fingerprints and multivariate analysis using Unscrambler X.10.4 and Metaboanalyst 4.0 software (e.g., PCA, PLSDA, cluster analysis, heatmap, Random forest analysis) and ANOVA post-hoc analysis using Fischer’s least significant difference. The integration of spectral and chemometric analysis proved to offer valuable criteria for their botanical group recognition, individual authenticity, and quality, easy to be applied for large cohorts of commercialized oils.

Contribution of Tocols to Food Sensorial Properties, Stability, and Overall Quality

This paper reviews the contribution of tocopherols and tocotrienols (tocols) to food quality as well as their bioactivity and health-promoting properties, which have attracted researchers and food technologists. Tocols are lipophilic phenolic antioxidants encompassing tocopherols that are characterized by a saturated side chain and tocotrienols with an unsaturated isoprenoid side chain. Tocols are natural constituents of several foods like dairy, vegetable oils, nuts, and grains. Their presence in foods, namely, as food additives, helps prevent lipid oxidation, which negatively affects the sensorial quality of foods, and even the nutritional value and safety. Supplementation of animals’ diets with tocopherols has proven its effectiveness in preserving fresh color and flavor of the meat. Although alfa-tocopherol displays much higher vitamin E activity than other tocols, health outcomes have been reported for tocotrienols, thus calling for more studies.