1,721,157 research outputs found
Polycyclic Aromatic Hydrocarbons (PAHs) in Olive Pomace Oil: Occurrence, Analytical Determination, and Mitigation Strategies
No full textEnvironmental pollution, agricultural practices, climate change, and the various stages of edible oil production are responsible for oil contamination with various chemicals. Among vegetable fats, olive pomace oils (OPOs) have higher polycyclic aromatic hydrocarbon (PAH) contents, exceeding the limits in some cases. Several methods for the determination of PAHs in animal and vegetable fats and oils have been published over the years, but they have often failed to eliminate matrix-specific interferences in OPO. The few methods proposed or applied for the specific analysis of PAHs in OPO over the past 20 years are mainly based on two different analytical approaches, namely liquid chromatography-fluorescence detector (LC-FLD) and gas chromatography-mass spectrometry (GC–MS). In the case of the LC-FLD approaches, liquid–liquid extraction with appropriate solvents and one or more purification steps on stationary phases of different compositions are performed. In the case of GC techniques, on the other hand, the most commonly used sample preparation is liquid–liquid partitioning. Due to widespread public concern about PAH contamination, several studies have been conducted to explore ways to mitigate the presence of PAHs in OPOs (i.e., refining processes)
Evaluation of the impact of olive milling on the mineral oil contamination of extra-virgin olive oils
No full textMineral oil saturated (MOSH) and aromatic hydrocarbons (MOAH) are environmental and processing contaminants also found in extra-virgin olive oil. Knowledge on contamination sources can help minimize them. The main objective of this work was to investigate the impact of milling operations. To this purpose, samples from 25 processing lines (at 5 different processing stages) were analyzed by online high-performance liquid chromatography—gas chromatography—flame ionization detection. A protocol for eliminating endogenous n-alkanes was tested and applied when necessary. Generally, transport to the mill had a negligible impact. The washing step had a mitigation impact, more evident on samples with higher contamination. On average, total MOSH decreased of 2.1 mg kg–1. Despite the reduction determined by washing, the entire milling process resulted in an increase in contamination (> 30%) for 20% of the processing lines. Total average MOSH and MOAH contamination increased by 2.3 and 0.6 mg kg–1, respectively. Practical Applications: This work aims to improve the knowledge on the presence and sources of mineral oil hydrocarbons (MOH), contaminants of petrogenic origin, in extra-virgin olive oil. In particular, this work investigates the impact of processing at the mill, including the transport stage, as well as the potential of the washing step in reducing the contamination. For the first time, a systematic study on this topic has been carried out. The knowledge of the contribution of individual steps in the production process to final product contamination is of paramount importance in identifying critical points on which to take action to mitigate contamination, and this is of great interest for all operators of the sector and for protecting consumer health, especially when considering possible presence of MOAH, which may include genotoxic and carcinogenic compounds
Analytical Determination of Squalene in Extra Virgin Olive Oil and Olive Processing By-Products, and Its Valorization as an Ingredient in Functional Food—A Critical Review
Full text linkSqualene is a bioactive compound with significant health benefits, predominantly found in extra virgin olive oil (EVOO) and its processing by-products. This critical review explores the analytical determination of squalene in EVOO and various by-products from olive oil production, highlighting its potential as a valuable ingredient in functional foods. An overview of existing analytical methods is provided, focusing on different approaches to sample preparation before analytical determination, evaluating their effectiveness in quantifying squalene concentrations. Studies not primarily centered on analytical methodologies or squalene quantification were excluded. A critical gap identified is the absence of an official method for squalene determination, which hinders comparability and standardization across studies, underscoring the importance of developing a reliable, standardized method to ensure accurate quantification. The valorization of squalene involves advocating for its extraction from olive oil processing by-products to enhance sustainability in the olive oil industry. By recovering squalene, the industry can not only reduce waste but also enhance functional food products with this health-promoting compound. Additionally, there is a need for economically sustainable and environmentally friendly extraction techniques that can be scaled up for industrial application, thus contributing to a circular economy within the olive oil sector
Monitoring and Occurrence of Heavy PAHs in Pomace Oil Supply Chain Using a Double-Step Solid-Phase Purification and HPLC-FLD Determination
Full text linkPolycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental and processing contaminants generated by both spontaneous and anthropogenic incomplete combustion processes of organic matter. Contamination of PAHs in vegetable oils can result from several factors and processes, including environmental contamination, oil processing, and migration from food contact materials. The determination of PAHs in edible oil presents a challenge because of the complexity of the matrix. Since PAHs are present at lower levels than triglycerides, it is necessary to isolate the compounds of interest from the rest of the matrix. To this purpose, a new purification approach based on a double solid-phase extraction (SPE) step followed by high performance liquid chromatography–fluorometric detector (HPLC-FLD) analysis was developed. The method involves a first purification step by using a 5 g silica SPE cartridge, previously washed with dichloromethane (20 mL), dried completely, and then conditioned with n-hexane (20 mL). The triglycerides are retained by the silica, while the PAH-containing fraction is eluted with a mixture of n-hexane/dichloromethane (70/30, v/v). After evaporation, the residue is loaded on a 5 g amino SPE cartridge and eluted with n-hexane/toluene (70/30, v/v) before HPLC-FLD analysis. The focus was the evaluation of the contribution of the various phases of the pomace oil supply chain in terms of the heavy PAHs (PAH8) concentration. Data collected showed that pomace contamination increased (by 15 times) as storage time increased. In addition, the process of pomace drying, which is necessary to reduce its moisture content before solvent extraction of the residual oil, appeared to significantly contribute to the total heavy PAHs content, with increases in value by up to 75 times
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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