Olive Oil Quality Research Articles

Relationships Between Chemical Compounds and Sensory Properties of Virgin Olive Oil in the US and Israel: Development of a Prediction Model for Defects.

Virgin olive oil (VOO) quality is defined by both chemical and sensory parameters. While the chemical parameters are objective and measured using instrument-based methods, sensory quality evaluation is based upon human panels, which can be subjective, have less repeatability, suffer from fatigue, and require long and costly training. Tasting biases could be minimized by a trained panel, but using humans as a testing instrument is inevitably prone to various psychological biases, stimulus-related factors, and carry-over effects. The objectives of this study were to evaluate instrumental methodologies that will assist the existing human panel in assessing the sensory characteristics of VOO and to develop chemistry-based predicting models for sensory properties in the oil using VOO samples originating from the US and Israel. Our results indicated that oil rancidity highly correlated with the contents of chemical components contents; 1-penten-3-one, 3-hexen-1-ol, (E)-2-pentanal, and 1-octen-3-ol are the major volatiles associated with rancidity defects (low concentrations of these compounds). Positive sensory attributes, such as fruitiness, correlated with 1- acetoxypinoresinol and hexanal, while bitterness correlated with pinoresinol, the aldehydic form of oleuropein aglycones, and the dialdehydic form of oleuropein aglycone. The random forest model suggested that luteolin, (E)-2-hexenal, 1-penten-3-one, and C18:0 are the most useful measurements in predicting the occurrence of sensory defects in the olive oil samples included. In other words, when these compounds are below or above a certain threshold, a defect, such as rancidity, is more likely to be found by the sensory panel.

Bactrocera oleae Control and Smart Farming Technologies for Olive Orchards in the Context of Optimal Olive Oil Quality: A Review

Bactrocera oleae Control and Smart Farming Technologies for Olive Orchards in the Context of Optimal Olive Oil Quality: A Review

Assessing statistical neural networks potentiality to distinguish PDO Kalamata and Molaoi olive oil varieties

Several regional areas in Greece produce high quality olive oil by cultivating certain varieties. Olive oil varieties of Kalamata and Molaoi are of special interest, since they produce extra virgin olive oil. Concretely, Kalamata is a city located in southwestern Greece. Intuitively, Molaoi is a town located in southeastern Greece. Subsequently, both geographic locations are known for their famous olive oil quality. Continually, Protected Designation of Origin (PDO) Kalamata olive oil, established by Council regulation (EC) No 510/2006, is considered an exceptional extra virgin olive oil variety. Specifically, there is a need to distinguish PDO Kalamata olive oil from other olive oil varieties is Greece such as the Molaoi olive oil, since PDO Kalamata olive oil is the main variety exported in the global olive oil market. Distinguishing PDO Kalamata from Molaoi olive oil is possible by incorporating statistical neural networks. Concretely, applying neural network experimentation enables differentiation between variations of certain chemical characteristics observed in certain geographic locations of Greece. In this paper, we use statistical neural networks to distinguish the geographical origin of PDO Kalamata olive oil compared with Molaoi olive oil based on synchronous excitation−emission fluorescence spectroscopy of provided olive oils samples evaluated in the chemical laboratory. Evaluation based on certain experimentation phase and subsequent data visualization of the adopted statistical neural networks are promising for distinguishing the samples of PDO Kalamata olive oil with high values of prediction accuracy. Such ability enables olive oil industry to assess extra virgin olive oil profitable potentiality in global market.

Machine learning-aided microRNA discovery for olive oil quality.

MicroRNAs (miRNAs) are key regulators of gene expression in plants, influencing various biological processes such as oil quality and seed development. Although, our knowledge about miRNAs in olive (Olea europaea L.) is progressing, with several miRNAs being identified in previous studies, but most of these reported miRNAs have been predicted without the aid of a reference genome, primarily due to limited genome accessibility at the time. However, significant knowledge gaps still need to be improved in this area. This study addresses the complexities of miRNA detection in olive, using a high quality reference genome and a combination of genomics and machine learning-based methods. By leveraging random forest and support vector machine algorithms, we successfully identified 56 novel miRNAs in olive, surpassing the limitations of conventional homology-based methods. Our subsequent analysis revealed that some of these miRNAs are implicated in the regulation of key genes involved in oil quality. Within the context of oil biosynthesis pathways, the novel miRNA Oeu124369 regulates fatty acid biosynthesis by targeting acetyl-CoA acyltransferase 1 and palmitoyl-protein thioesterase, thereby influencing the production of acetyl-CoA and palmitic acid, respectively. These findings underscore the power of machine learning in unraveling the complex miRNA regulatory network in olive and provide a high quality miRNA resource for future research aimed at improving olive oil production by exploring the target genes of the identified miRNAs to understand their role and their biological processes.

Evaluation of phenolics in the analysis of virgin olive oil using near infrared spectroscopy

Olive oil is an indispensable part of the diet in Mediterranean regions, and is appreciated worldwide for its sensory characteristics, combining a fine aroma and pleasant flavor with the high nutritional value of specific chemical compounds. However, making rapid measurements of phenolic compounds is a major challenge for the olive oil sector. The development of a new method based on near infrared (NIR) spectroscopy may be considered an important advance for the sector, as it is rapid, low-cost, non-contaminant and non-destructive. In this study, three different NIR instruments – one FT-NIR benchtop instrument (671.82–2702.70 nm) and two low-cost portable devices (900–1700 nm and 1350–2150 nm) – were used to analyze a collection of virgin olive oil samples from various Mediterranean regions. To predict both the individual and total concentration of phenols in the olive oil, four signal pretreatment methods and modified partial least squares regression analyses were employed to develop the predictive models. The results showed that the benchtop FT-NIR instrument performed better than the other portable instruments when measuring the phenolic compounds in virgin olive oil. The best models of hydroxytyrosol derivatives, tyrosol derivatives, total phenols and “EFSA phenols” showed R2cv values of 0.84, 0.85, 0.88 and 0.89, while the RPDcv values were 2.51, 2.61, 2.93 and 2.95, respectively. Meanwhile, for the portable NIR instruments, the prediction models for hydroxytyrosol derivatives, total phenols and “EFSA phenols” (the sum of the hydroxityrosol and tyrosol derivatives) showed R2cv values ranging between 0.75 and 0.81 and an RPDcv between 2 and 2.5. These results indicate the great potential of NIR, both with benchtop and portable devices, to detect phenolic compounds in virgin olive oil, which can guarantee the quality of virgin olive oil and thus aid progress in the olive oil industry. Moreover, this is the first published work to determine phenolic compounds in virgin olive oil using portable NIR instruments.

Future aridity and drought risk for traditional and super-intensive olive orchards in Portugal

Portugal, a leading olive oil producer, boasts six Protected Denomination of Origin (PDO) regions, with distinct olive orchard (OR) densities (traditional rainfed to super-intensive irrigated). This study aimed to assess future drought and aridity conditions and the impacts on ORs located in the PDOs. Therefore, drought and aridity indicators were considered for the historical (ERA5: 1981–2000) and future periods (2041–2060; 2081–2100), and anthropogenic forcing scenarios (RCP4.5 and RCP8.5), using a 7-member ensemble of global climate models. From Spearman’s correlation analysis, Annual Mean Aridity (AIA) was selected as the most representative indicator of the climate conditions, to which the ORs were exposed. Readily Available Soil Water (RAW; mm) was considered to represent the available soil water reservoir for olive trees. Moreover, the Olive Drought and Aridity Risk Index (ODAR) was developed to determine each OR's future risks. This index considered that the AIA and RAW were weighted by OR density fractions. In the future, southern Portugal will be more arid (0.69) than northern and central (0.60). ORs soil shows lower RAW in southern PDOs (< 60 mm) than in central and northern regions (> 90 mm). These results suggest that the south of ORs will be more exposed to water stress than the northern regions. According to ODAR, the ORs exposed to low and high risk will be mainly located in the central parts of the PDOs. In northern ORs, moderate to high risk will predominate. In the south, however, the risk will be very high, which means that the olive tree growth, fruit development, and olive oil quality could be negatively affected. Implementation of tailored adaptation measures will be required to improve the climate resiliency of the sector.

Interplay of phenolic compounds and gene expression in phenylpropanoid and flavonoid pathways during olive (Olea europaea L.) ripening of ‘Leccino’ cultivar

This study presents a detailed analysis and interplay of the phenolics, relative gene expression and quality parameters during ripening of ‘Leccino’ olive fruit pulp and skin at seven maturity indexes, in the phenylpropanoid and flavonoid pathways. Tissue-specific gene expression analysis revealed statistically higher expression levels for eight genes in the skin. The only exception was anthocyanidin synthase (ANS), which expression level was statistically higher in the pulp. Our results confirm that the important role in olives of the anthocyanin composition have flavonoid 3′-hydroxylase (F3′H) and flavonoid-3′,5′-hydroxylase (F3′5′H) in both tissues. The phenolic content was mostly statistically higher in the skin than in the pulp and generally increased in both tissues during ripening. A notable shift in phenolic compounds occurs between maturity index 3 and 4, when the skin of the fruit turns completely purple. Results from this study highlight the intricate dynamics of physiological processes and biochemical mechanisms in the phenylpropanoid and flavonoid pathways in olive fruit. The findings also underscore the relationship between phenolic content, relative gene expression, and quality parameters, particularly in relation to color development during ripening in different olive fruit tissues. Our conclusions can be used by growers to improve the quality of fruit and consequently the quality of olive oil or other final products.

Physicochemical Characteristics and Antioxidant Activity of Some Algerian Extra Virgin Olive Oils (Olea europaea L.)

Background:: The present work was conducted to investigate the quality and antioxidant properties of some Algerian extra virgin olive oils (EVOOs). Objective:: In this paper, the physicochemical characteristics and antioxidant properties of four EVOOs of monovarietal samples (Chemlal) from East Algeria were studied. Methods:: Physicochemical characteristics, which include free acidity, peroxide index, saponification index, specific extinction coefficients, water content, refractive index, relative density, and chemical composition, in addition to their antioxidant activity, were investigated based on DPPH free radical-scavenging activity (DPPH-SA). Results:: The results of physicochemical and quality parameters proved that all samples are EVOOs with highly nutritious and health benefits for the consumer, as per the recommendation of the International Olive Council (IOC). The results showed that the olive oils from the southern arid region of Algeria (Sahara), have a high antioxidant activity than the samples from the Northern regions. Conclusion:: These findings revealed a significant influence of geographic location on the chemical characteristics and antioxidant activities of olive oil from the same cultivar (Chemlal). These olive oils from the arid Saharan region may be used as a functional food with great antioxidant potential.

Study of the quality of olive oils imported to Russia

Study of the quality of olive oils imported to Russia

Long-term stability of extra virgin olive oil: effects of filtration and refrigeration storage on the Kolovi variety.

The composition of extra virgin olive oil (EVOO) defines its sensory, nutritional, and human health benefits, and distinguishes it as a key component of the Mediterranean diet. Nevertheless, EVOO constituents are susceptible to degradation during processing and storage, which reduces the olive oil's quality and limits its shelf life. The present study investigated the effect of molecular filtration before storage and the effect of cool storage at 4 °C on the stability of 'Kolovi' EVOO, a variety originating from the Greek island of Lesvos, over a 24 month period. Storing EVOO at 4 °C positively affected free acidity, peroxide value, K268, fruity qualities, and concentrations of hydroxytyrosol, tyrosol, ligstroside aglycone, lutein, and squalene, in comparison with the control sample stored at room temperature, particularly after 1 year. Molecular filtration significantly affected the ratio of unsaturated fatty acids to saturated fatty acids (UFAs/SFAs). Optimal preservation of parameters such as acidity value and lutein content was achieved by combining molecular filtration with refrigeration. The present study recommends storing EVOO in the refrigerator for up to 18 months. Based on the regulatory limits of the quality characteristics of acidity, peroxide value, K232 value and fruity sensory attributes, the shelf-life of the protected geographical indication (PGI) 'Kolovi' EVOO can reach 2 years under cool storage (4 °C) and with molecular filtration before storage. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Genetic and Phytopathogenic Characterization of Endemic Colletotrichum Isolates in Major Olive Cultivars of Greece

Olive anthracnose outbreaks caused by the Colletotrichum species complex in the Mediterranean region decrease both fruit yield and olive oil production while also drastically degrading olive oil quality. The presence of various Colletotrichum species able to produce disease symptoms in olive fruits significantly deteriorates the efforts for an efficient crop protection strategy. In this report, the major olive productive area of Peloponnese was screened for Colletotrichum species capable of generating anthracnose symptoms. Olive fruits of 12 different olive cultivars were collected from 60 groves distributed analogously in the Peloponnese. Thirty-two fungal strains isolated from asymptomatic olive drupes were identified morphologically as Colletotrichum spp. and were multilocus genetically analyzed. The 32 isolates were grouped into two primary lineages resembling the previously characterized Colletotrichum acutatum and Colletotrichum nymphaeae based on the conducted genetic analysis for five genetic loci. The virulence of 16 Colletotrichum spp. strains were evaluated in a detached fruit assay of 10 Greek olive cultivars. The results clearly suggested that fungal isolates belonging to both C. acutatum and C. nymphaeae exhibited different levels of pathogenicity in a cultivar-dependent manner. Thus, cultivars examined in terms of the % Disease Index (%DI) were divided into highly tolerant, tolerant, and susceptible, and those analyzed regarding the % Disease Severity Index (%DSI) were divided into tolerant and susceptible. Our results suggest that the Greek cultivars of Athinolia and Megaritiki are highly tolerant to the vast majority of Colletotrichum strains isolated from Peloponnesian groves and consist of a significant genetic material for the future design of crop protection programs against anthracnose breakouts.

Chemical Characterization, Stability and Sensory Evaluation of Sicilian Extra Virgin Olive Oils: Healthiness Evidence at Nose Reach.

The aim of this study was to assess the nutraceutical qualities of extra virgin olive oil (EVOO) samples obtained from three Sicilian olive cultivars: Nocellara, Biancolilla, and Cerasuola. We also evidenced the relationship among biophenols, base parameters and panel test scores, and evaluated the stability of the biophenols in EVOO. The assessment also took into consideration variations in olive harvesting periods and the influence of four different milling methods. A statistical analysis of the collected data revealed that the cultivar and harvesting period were the primary factors influencing the bio-phenol content, while the milling methods employed did not significantly affect the levels of biophenols in the oils. The panel test results were also illuminating as they were strongly related to the cultivar and polyphenol content. Following the criteria outlined in EC Regulation 432/2012, we selected three samples, each representing one of the cultivars, which exhibited the highest bio-phenol content to evaluate the biophenol stability during a time span of 16 months.

Maximizing Antioxidant Potential in Picual Virgin Olive Oil: Tailoring Agronomic and Technological Factors with Response Surface Methodology.

Over the past years, a prolonged drought has affected Spain, raising significant concerns across various sectors, especially agriculture. This extended period of dry weather is profoundly affecting the growth and development of olive trees, potentially impacting the quality and quantity of olive oil produced. This study aims to assess the impact of agronomic factors, i.e., olive maturation and irrigation management, as well as the technological factors involved in the production process, on the antioxidant content of Picual virgin olive oil. Mathematical models were developed to maximize the concentration of polyphenols, orthodiphenols, chlorophylls, carotenes, and tocopherols in olive oils. Findings indicate that increasing the malaxation temperature from 20 to 60 °C and reducing the mixing time from 60 to 20 min positively influenced the polyphenol and orthodiphenol content. Although irrigation did not significantly affect the polyphenols, pigments, and α-tocopherol contents, it may enhance the β- and γ-tocopherol content. Optimal conditions for producing antioxidant-enriched virgin olive oils involved olives from rainfed crops, with a moisture index of 3-4, and a 60-min malaxation process at 60 °C. Under these conditions, the total phenol content doubled, pigment content increased fourfold, and α-tocopherol content rose by 15%. These findings provide relevant knowledge to interpret the year-to-year variation in both organoleptic and analytical profiles of virgin olive oils.

Combined effects of cultivar, extraction technology, and geographic origin on physicochemical traits of Moroccan olive oil as revealed by multivariate analysis

This study aimed at evaluating physicochemical traits of olive oil (‘Haouzia’ and ‘Moroccan Picholine’) according to extraction technologies (ETs: super-pressure SP, 2-phase 2 P, and 3-phase 3 P) across eight climatically contrasted Moroccan agroclimatic areas (AA). Our samples were classified as extra virgin olive oil (EVOO), whose traits varied (p < 0.05) among ETs, cultivars, and AA. EVOO from SP had high records of basic indices, most phytosterols, and trans fatty acids (TFA) due to partial oxidation during extraction, while continuous ETs (2 P and 3 P) displayed a better oil quality as demonstrated by routinely measured parameters. ‘Haouzia’ had the greatest saturated (SFA), monounsaturated (MUFA), polyunsaturated fatty acids (PUFA), and TFA. However, it had a lesser stability revealed by a low MUFA/PUFA and oleic/linoleic (O/L) as compared to ‘Moroccan Picholine’. Arid climatic areas had the highest palmitoleic, oleic acid, MUFA, MUFA/PUFA, and O/L and therefore the best oil stability as compared to the remaining agroclimatic areas. These variations were confirmed by principal component analysis, cluster analysis, and artificial neural networks. Important simple and multiple regression models with strong correlations were highlighted among the studied variables. In conclusion, environmental conditions have a key role to be considered when assessing olive oil quality and authenticity.

How the "Olive Oil Polyphenols" Health Claim Depends on Anthracnose and Olive Fly on Fruits.

Olive anthracnose, caused by Colletotrichum fungi, and the olive fruit fly Bactrocera olea are, respectively, the most important fungal disease and pest affecting olive fruits worldwide, leading to detrimental effects on the yield and quality of fruits and olive oil. This study focuses on the content of hydroxytyrosol (HYT) and its derivatives (the "olive oil polyphenols" health claim) in olive oils extracted from fruits of 'Galega Vulgar' and 'Cobrançosa' cultivars, naturally affected by olive anthracnose and olive fly. The olives, with different damage levels, were harvested from organic rainfed orchards, located in the center of Portugal, at four harvest times over three years. Galega oils extracted from olives with a higher anthracnose and olive fly incidence showed no conformity for the extra virgin olive oil (EVOO) and virgin olive oil (VOO) categories, presenting high acidity and negative sensory notes accompanied by the disappearance of oleacein. Conversely, no sensory defects were observed in Cobrançosa oils, regardless of disease and pest incidence levels, and quality criteria were still in accordance with the EVOO category. The total HYT and tyrosol (TYR) content (>5 mg/20 g) allows for the use of the "olive oil polyphenols" health claim on the label of all the analyzed Cobrançosa olive oils.

Factors that Affect the Quality of Olive Oil Produced Using Olives from Traditional Orchards in the Middle East

Traditional olive (Olea europaea) orchards have been grown for thousands of years and still occupy most of the world’s cultivated olive areas. To compete with olive oil produced in the higher-yielding intensive orchards, the oil from traditional orchards must be of high quality. We evaluated oil quality—potential and actual (under commercial conditions)—and tested the stages in the production chain that are likely to reduce oil quality in the traditional sector in the Middle East region. Our findings show a clear negative impact of growers’ traditional practices on both the chemical and sensory characteristics of olive oil. The oil originating from the commercial process had higher free fatty acid and lower polyphenol and carotenoid contents, lower stability, lower pungency, lower fruitiness, lower bitterness, and a higher prevalence of organoleptic defects than oil that originated from fruit picked from the same trees during the experimental procedure. The current common harvesting technique of pole beating significantly increased fruit injury and fruit with mold, leading to a reduction in oil polyphenols and an increase in free fatty acid levels compared with those resulting from manual picking. In addition, after harvest, storing the fruit for more than 48 hours in plastic bags dramatically reduced the oil quality. The traditional olive orchard could be a source of high-quality extra virgin olive oil. However, fruit handling—from the trees until the end of the oil extraction process—is performed incorrectly, thus adversely affecting the oil quality.

Engraved Split-Ring Resonators as Potential Microwave Sensors for Olive Oil Quality Control

Engraved Split-Ring Resonators as Potential Microwave Sensors for Olive Oil Quality Control

Assessing the Effectiveness of Pruning in an Olive Orchard Using a Drone and a Multispectral Camera: A Three-Year Study

The uses of precision oliviculture have increased in recent years to improve the quality and quantity of extra virgin olive oil. In traditional and intensive systems, biennial pruning is often applied to balance and maintain plant vigour, aiming at reducing management costs. This study presents the results of a three-year experiment with the objective of quantifying the effects of biennial pruning on the vegetative vigour of olive trees, investigating the geometric and spectral characteristics of each canopy determined with multispectral images acquired by UAV. The experiment was carried out in an olive orchard located in western Sicily (Italy). Multispectral images were acquired using a UAV in automatic flight configuration at an altitude of 70 m a.g.l. The segmentation and classification of the images were performed using Object-Based Image Analysis (OBIA) based on the Digital Elevation Model (DEM) and orthomosaic to extract the canopy area, height, volume and NDVI for each plant. This study showed that the technology and image analysis processing used were able to estimate vigour parameters at different canopy densities, compared to field measurements (R2 = 0.97 and 0.96 for canopy area and volume, respectively). Furthermore, it was possible to determine the amount of removed biomass for each plant and vigour level. Biennial pruning decreased the number of plants initially classified as LV (low-vigour) and maintained a vegetative balance for MV (medium-vigour) and HV (high-vigour) plants, reducing the spatial variability in the field.

Consumption of Olive Oil and Diet Quality and Risk of Dementia-Related Death

Age-standardized dementia mortality rates are on the rise. Whether long-term consumption of olive oil and diet quality are associated with dementia-related death is unknown. To examine the association of olive oil intake with the subsequent risk of dementia-related death and assess the joint association with diet quality and substitution for other fats. This prospective cohort study examined data from the Nurses' Health Study (NHS; 1990-2018) and Health Professionals Follow-Up Study (HPFS; 1990-2018). The population included women from the NHS and men from the HPFS who were free of cardiovascular disease and cancer at baseline. Data were analyzed from May 2022 to July 2023. Olive oil intake was assessed every 4 years using a food frequency questionnaire and categorized as (1) never or less than once per month, (2) greater than 0 to less than or equal to 4.5 g/d, (3) greater than 4.5 g/d to less than or equal to 7 g/d, and (4) greater than 7 g/d. Diet quality was based on the Alternative Healthy Eating Index and Mediterranean Diet score. Dementia death was ascertained from death records. Multivariable Cox proportional hazards regressions were used to estimate hazard ratios (HRs) and 95% CIs adjusted for confounders including genetic, sociodemographic, and lifestyle factors. Of 92 383 participants, 60 582 (65.6%) were women and the mean (SD) age was 56.4 (8.0) years. During 28 years of follow-up (2 183 095 person-years), 4751 dementia-related deaths occurred. Individuals who were homozygous for the apolipoprotein ε4 (APOE ε4) allele were 5 to 9 times more likely to die with dementia. Consuming at least 7 g/d of olive oil was associated with a 28% lower risk of dementia-related death (adjusted pooled HR, 0.72 [95% CI, 0.64-0.81]) compared with never or rarely consuming olive oil (P for trend < .001); results were consistent after further adjustment for APOE ε4. No interaction by diet quality scores was found. In modeled substitution analyses, replacing 5 g/d of margarine and mayonnaise with the equivalent amount of olive oil was associated with an 8% (95% CI, 4%-12%) to 14% (95% CI, 7%-20%) lower risk of dementia mortality. Substitutions for other vegetable oils or butter were not significant. In US adults, higher olive oil intake was associated with a lower risk of dementia-related mortality, irrespective of diet quality. Beyond heart health, the findings extend the current dietary recommendations of choosing olive oil and other vegetable oils for cognitive-related health.

Simultaneous development and validation of an HPLC-UV method for the analysis of bisphenol A in Moroccan extra virgin olive oil stored in plastic bottles

This study explores the migration of Bisphenol A (BPA) from plastic packaging to Moroccan extra virgin olive oil (EVOO), a key Mediterranean diet component. Assessing the impact of plastic containers on olive oil quality and safety, the research investigates the influence of olive oil acidity on BPA release using an HPLC-UV method. Despite BPA’s known environmental and health risks, detectable levels persist in human samples, emphasizing the need for strict control. Examining 30 olive oil samples from the Beni Mellal-Khenifra region stored in plastic bottles, the study revealed BPA levels above the daily intake limits set by EFSA in its latest version (0.2 ng/kg body weight per day), reaching (0.238 ppm) in polycarbonate (PC) bottles and (0.144 ppm) in polyethylene (PE) bottles. It advocates for controlled packaging and highlights the delicate balance between convenience and consumer well-being. The findings call for informed choices in production and storage practices, urging increased scrutiny of food packaging for enhanced public health and regulatory measures.