Emissions of volatile aldehydes from heated cooking oils

Visualising household air pollution: Colorimetric sensor arrays for monitoring volatile organic compounds indoors

Indoor air quality monitoring as it relates to the domestic setting is an integral part of human exposure monitoring and health risk assessment. Hence there is a great need for easy to use, fast and economical indoor air quality sensors to monitor the volatile organic compound composition of the air which is known to be significantly perturbed by the various source emissions from activities in the home. To meet this need, paper-based colorimetric sensor arrays were deployed as volatile organic compound detectors in a field study aiming to understand which activities elicit responses from these sensor arrays in household settings. The sensor array itself is composed of pH indicators and aniline dyes that enable molecular recognition of carboxylic acids, amines and carbonyl-containing compounds. The sensor arrays were initially deployed in different rooms in a single household having different occupant activity types and levels. Sensor responses were shown to differ for different room settings on the basis of occupancy levels and the nature of the room emission sources. Sensor responses relating to specific activities such as cooking, cleaning, office work, etc were noted in the temporal response. Subsequently, the colorimetric sensor arrays were deployed in a broader study across 9 different households and, using multivariate analysis, the sensor responses were shown to correlate strongly with household occupant activity and year of house build. Overall, this study demonstrates the significant potential for this type of simple approach to indoor air pollution monitoring in residential environments.

Distribution of aldehydes compared to other oxidation parameters in oil matrices during autoxidation

Distribution of aldehydes between headspace (HS) and inner matrix (IM) of bulk oil or oil-in-water (O/W) emulsion was determined and contents of aldehydes were compared with other oxidation parameters in soybean oil or O/W emulsion during 50 °C autoxidation. Bulk oil matrix had higher portion of IM aldehydes than O/W emulsion. HS aldehydes in O/W emulsion reflected aldehyde content better than in bulk oil. Moisture content in soybean oil increased distinctively before the generation of oxidation products including hydroperoxides and volatiles. HS aldehydes and other oxidation parameters were simultaneously increased in soybean oil. In case of O/W emulsion, HS aldehydes had a sudden increase point while lipid hydroperoxides and conjugated did not show such increase during autoxidation. HS aldehydes reflected oxidation stage better in O/W emulsion than in bulk oil based on partition distribution and linear changes during autoxidation.

A sensitive chemiluminescence detection approach for determination of 2,4-dinitrophenylhydrazine derivatized aldehydes using online UV irradiation - luminol CL reaction. Application to the HPLC analysis of aldehydes in oil samples

Aldehydes are toxic carbonyl compounds that are identified in various matrices surrounding us. For instance, aldehydes could be formed during the cooking and frying of foods which affects the food quality and safety. Derivatization is a must for the determination of aldehydes as they lack intrinsic chromophoric groups. 2,4-Dinitrophenyl hydrazine (DNPH) is the most used derivatizing reagent for aldehydes and the formed hydrazones could be determined by either HPLC-UV or LC-MS. However, UV detection is non-sensitive, and the MS equipment is expensive and not widely available. Thus, herein we report a smart chemiluminescence (CL) detection method for the DNPH aldehydes derivatives. These derivatives are supposed to possess photosensitization ability due to the presence of strong chromophoric structures; nitrobenzene and phenyl hydrazone. Upon their UV irradiation, singlet oxygen is found to be produced which then converts the DNPH-aldehyde derivative into hydroperoxide. Next, the hydroperoxide reacts with luminol in an alkaline medium producing a strong CL. An HPLC system with online UV irradiation and online reaction with luminol followed by CL detection was constructed and used for the determination of aldehydes after their derivatization with DNPH. The developed method showed excellent sensitivity with detection limits down to 1.5-18.5 nM. The achieved sensitivity is superior to that obtained by HPLC-UV and LC-MS detection methods for DNPH-aldehydes derivatives. Additionally, our approach is an chemiluminogenic where the DNPH reagent itself does not produce CL which is an excellent advantage. The method was applied successfully for the determination of aldehydes in canola oil samples using simple liquid-liquid extraction showing good recovery (87.0-106.0%), accuracy (87.2-106.6), and precision (RSD≤10.2%). After analysis of fresh and heated oil samples, it was demonstrated that heating of oil, even for short time, strongly elevated the level of their aldehydes' content. At last, it was found that the results of the analysis of aldehydes in oil samples using the proposed method perfectly matched those obtained by a reference LC-MS method.

Chronic bronchitis and emphysema among workers exposed to dust, vapors, or fumes by industry and occupation

Exposures to dust, vapors, or fumes (DVF) are associated with chronic bronchitis (CB) and emphysema. The 2007-2012 National Health and Nutrition Examination Survey data were used to estimate age-standardized prevalence of CB and emphysema among ever-employed adults by exposure status and industry and occupation groups. Age-standardized CB and emphysema prevalence were 2.3% and 1.9%, respectively. Of the estimated 111 million U.S. workers exposed to DVF, 2.7% reported CB and 2.8% reported emphysema. Workers in the "accommodation, food services" industry and "food preparation, serving related" occupations were more likely to report CB and emphysema. Current findings indicate that workplace exposures may be associated with high prevalence of CB and emphysema in certain industry and occupational groups. Early diagnosis and identifying associated workplace exposures are important steps in CB and emphysema prevention efforts.

Impact of physical activity and cooking oil amongst diabetes with coexisting hypertension patients on economic cost and length of stay: A 1914 patient's observational study

AIM OF THE STUDY

The study aimed to investigate the impact of the patients' physical activity status and the type of cooking oil consumed by patients in their daily routine on glycaemic profile, lipid profile, the hypertensive profile of the patients, the length of stay and overall cost of the treatment.

METHODS

This is a prospective observational study. All the patients referred to the medicine department of the three different hospitals located in Moga, City Punjab, and those hospitalised due to diabetes mellitus (types I and II) with coexisting hypertension were asked to participate in the study.

RESULTS

The patients' mean age was found to be M = 53.85, SD = 11.54 years. Out of 1914 patients, 914 were male (47.8%); it was observed that the majority of the patients 525 (27.43%) in North India using butter or ghee-clarified butter as edible oil, followed by mustard oil 517 (27.01%) patients. About 345 (18.03%) of the patients consume soybean oil, whereas 226 (11.81%) of the patients like sunflower oil.

CONCLUSION

This study explored that cooking oil and physical activity are associated with length of stay in days and overall cost of the treatment, respectively. Our study results revealed that the type of oil compared with the treatment's overall cost was significant for olive oil, soybean oil and groundnut oil. The study revealed that moderate and low physical activity increases the length of stay compared to high physical activity. The consumption of olive oil as a regular food habit in daily routine decreases patients' length of stay with diabetes with coexisting hypertension when doing high physical activity but increases the overall cost of treatment.

Cooking activities in a domestic kitchen: Chemical and toxicological profiling of emissions

To obtain emission factors and cooking-related chemical signatures, a monitoring campaign was carried out in a modern kitchen where different dishes of the Latin cuisine were prepared. Particulate matter (PM₁₀, PM_2.5 and PM₁) and total volatile organic compounds (TVOCs) were continuously measured. Passive tubes for carbonyls and a high volume PM₁₀ sampler were simultaneously used. PM₁₀ filters were analysed for organic and elemental carbon and for multiple organic compounds, including polyaromatic hydrocarbons (PAHs). The toxic potential of PM₁₀ was evaluated using a bioluminescence inhibition bioassay. Acrolein was never detected, while formaldehyde and acetaldehyde levels were comparable to those in the background air. The protection limit for TVOCs was always exceeded. Fine particles comprised more than 86% of the PM₁₀ mass concentrations. PM₁₀ emission rates ranged from 124 to 369 μg min^-1. Relatively low PAH concentrations were obtained. PM₁₀ encompassed alcohols, acids, plasticisers, alkyl esters, sterols, sugars, polyols, glyceridic compounds, phenolics, among others. Total concentrations were 1.9-5.3 times higher during cooking than in the background air but, for some compounds, differences of tens or hundreds of times were registered. PM₁₀ from grilled pork was found to contribute to non-negligible cancer risks and to be very toxic, while samples from other dishes were categorised as toxic.

Modified Camellia oleifera Shell Carbon with Enhanced Performance for the Adsorption of Cooking Fumes

Using Camellia oleifera shell (COS) as a raw material and phosphoric acid as the activator, activated Camellia oleifera shell carbon (COSC-0) was prepared and then modified by Fenton’s reagent (named as COSC-1). SEM, GC-MS, FTIR, and specific surface area and pore analyzers were used to study the adsorption performance of COS, COSC-0, and COSC-1 on cooking fumes. Results showed that COSC-1 was the best adsorbent compared with COS and COSC-0. The adsorption quantity and penetrating time of COSC-1 were 44.04 mg/g and 4.1 h, respectively. Most aldehydes could be adsorbed by COSC-1, which was due to the large number of carbonyl and carboxyl groups generated on the surface of COSC-1 from the action of Fenton’s reagent. The adsorption effect of COSC-1 on different types of pollutants in cooking fumes was analyzed based on the similar compatibility principle. COSC-1 showed a much higher adsorption effect on the strong polarity functional groups than on weak polar groups. The results provide a theoretical basis for the application of Camellia oleifera shell carbon adsorption technology in the treatment of cooking fumes.

High-Resolution Exposure Assessment for Volatile Organic Compounds in Two California Residences

Time spent in residences substantially contributes to human exposure to volatile organic compounds (VOCs). Such exposures have been difficult to study deeply, in part because VOC concentrations and indoor occupancy vary rapidly. Using a fast-response online mass spectrometer, we report time-resolved exposures from multi-season sampling of more than 200 VOCs in two California residences. Chemical-specific source apportionment revealed that time-averaged exposures for most VOCs were mainly attributable to continuous indoor emissions from buildings and their static contents. Also contributing to exposures were occupant-related activities, such as cooking, and outdoor-to-indoor transport. Health risk assessments are possible for a subset of observed VOCs. Acrolein, acetaldehyde, and acrylic acid concentrations were above chronic advisory health guidelines, whereas exposures for other assessable species were typically well below the guideline levels. Studied residences were built in the mid-20th century, indicating that VOC emissions even from older buildings and their contents can substantially contribute to occupant exposures.

Chemosensory Device Assisted-Estimation of the Quality of Edible Oils with Repetitive Frying

This study investigated chemosensory degradations of soybean and canola oils with repeated frying in order to estimate the quality of the oils. Methods: Chemical parameters including oxygen induction time, acid value, p-anisidine value, malondialdehyde, and total polar compounds were measured. Electronic nose and electronic tongue analyses were performed to assess sensory properties. Multivariate analyses were employed to investigate relationships among tastes and volatile compounds using principal component analysis (PCA) and Pearson’s correlation analysis. Results: All chemical parameters increased with repeated frying in both oils. Electronic nose analysis found ethyl butyrate, 2-heptenal, and 2,4-pentanedione as major volatiles for soybean oil and ethyl butyrate and linalool for canola oil. As the numbers of frying increased, all volatiles showed an increased concentration in various extents. In multivariate analyses, ethyl butyrate revealed strong positive correlations with sourness, umami, and sweetness, and umami showed strong positive correlations with sourness and saltiness (p < 0.05). PCA confirmed that in PC1 with 49% variance, sourness, saltiness, and umami were at similar rates while acetyl pyrazine, 2,4-pentadieone, and 1-octanol were found at similar rates. Canola oil was chemically more stable and less susceptible to deterioration in all chemical parameters compared to soybean oil, resulting in a relatively better quality oil when repeatedly fried. Conclusion: The results suggested that minimum repeated frying (5 times) degrades chemosensory characteristics of both oils, thereby compromising their quality. The findings of this study will be utilized as a foundation for quality control of fried foods in food industry, fried food development, and fast-food industry.

Heated Corn Oil and 2,4-Decadienal Suppress Gastric Emptying and Energy Intake in Humans

Consumption of 2,4-decadienal (2,4-DD) delays gastric emptying (GE) rate in animals. Oil heating produces 2,4-DD and other aldehydes. Here we examined whether heated oil affects GE rate and food intake in humans, and whether it is mediated by 2,4-DD. In the first experiment, 10 healthy volunteers consumed 240-g pumpkin soup with 9.2 g of heated (HO) or non-heated corn oil (CO). Subsequently, 17 participants consumed pumpkin soup containing 3.1 g of either heated corn oil (HO), 1 mg 2,4-DD + non-heated corn oil (2,4-DD), or non-heated corn oil (CO). Sixty minutes following pumpkin soup, cod roe spaghetti was provided, and then energy intake was determined. To evaluate GE rate, ¹³C breath test (Experiment 1) and ultrasonography (Experiments 1 and 2) were used. The results from the Experiment 1 confirmed that consumption of heated corn oil reduced GE rate. Experiment 2 showed a delayed GE rate in HO and 2,4-DD trials compared with CO trial (p < 0.05). Energy intake was approximately 600–650 kJ lower in HO and 2,4-DD trials compared with CO trial (p < 0.05). These findings suggest that 2,4-DD, either formed by oil heating or added to food, contributes to suppressing GE rate and energy intake.

Reduction of aldehyde emission and attribution of environment burden in cooking fumes from food stalls using a novel fume collector

Uncontrolled cooking emissions from commercial kitchens are problematic due to their corresponding health effects and malodors. To reduce cooking emissions, medium and large commercial kitchens install air pollution control devices, such as electrostatic precipitators and wet scrubbers, while small-scale commercial cooking workplaces, such as street-food stalls, use smaller, simpler, and less costly filtration and absorption devices. However, these smaller devices may be poorly designed and recirculate cooking emissions in the workplace. The objectives of this study were to design and implement a novel fume collector and evaluate its effectiveness in reducing aldehydes and the corresponding environmental burden emitted by food stalls. Two stalls, which had malodor problems despite the use of fume collectors, volunteered to participate in the study. To increase the efficiency of the existing fume collectors, a new collector was designed comprising two buckets connected in series, each with pollutant absorption (NaClO-surfactant mixed solution) and particulate filtration (activated-carbon filters) components. Total aldehyde concentrations measured at the exhaust outlets of the original and new collectors were 342.2 and 80.8 μg/m³ for stall A, and 622.7 and 283.1 μg/m³ for stall B, respectively. The corresponding concentration reductions for stall A and B were 76% and 55%, and the emission rate reductions were 91% (from 749 to 71 g/yr) and 76% (from 1040 g/yr to 248 g/h), respectively. These results demonstrate that the effectiveness of the novel collector at removing cooking fumes was significantly improved. The high efficiency and low-cost nature of the collector make it highly applicable in small-scale commercial kitchens and street-food stalls.

Colorimetric Sensing of Volatile Organic Compounds Produced from Heated Cooking Oils

Measurement of cooking-associated air pollution indoors is an integral part of exposure monitoring and human health risk assessment. There is a need for easy to use, fast, and economical detection systems to quantify the various emissions from different sources in the home. Addressing this challenge, a colorimetric sensor array (CSA) is reported as a new method to characterize volatile organic compounds produced from cooking, a major contributor to indoor air pollution. The sensor array is composed of pH indicators and aniline dyes from classical spot tests, which enabled molecular recognition of a variety of aldehydes, ketones, and carboxylic acids as demonstrated by hierarchical clustering and principal component analyses. To demonstrate the concept, these CSAs were employed for differentiation of emissions from heated cooking oils (sunflower, rapeseed, olive, and groundnut oils). Sensor results were validated by gas chromatography-mass spectrometry analysis, highlighting the potential of the sensor array for evaluating cooking emissions as a source of indoor air pollution.

Comprehensive Study on the Acrylamide Content of High Thermally Processed Foods

Acrylamide (AA) formation in starch-based processed foods at elevated temperatures is a serious health issue as it is a toxic and carcinogenic substance. However, the formation of more AA entangles with modern-day fast food industries, and a considerable amount of this ingredient is being consumed by fast food eaters inadvertently throughout the world. This article reviews the factors responsible for AA formation pathways, investigation techniques of AA, toxicity, and health-related issues followed by mitigation methods that have been studied in the past few decades comprehensively. Predominantly, AA and hydroxymethylfurfural (HMF) are produced via the Maillard reaction and can be highlighted as the major heat-induced toxins formulated in bread and bakery products. Epidemiological studies have shown that there is a strong relationship between AA accumulation in the body and the increased risk of cancers. The scientific community is still in a dearth of technology in producing AA-free starch-protein-fat-based thermally processed food products. Therefore, this paper may facilitate the food scientists to their endeavor in developing mitigation techniques pertaining to the formation of AA and HMF in baked foods in the future.

Release Kinetics Studies of Early-Stage Volatile Secondary Oxidation Products of Rapeseed Oil Emitted during the Deep-Frying Process

The research concerns the use of proton transfer reaction mass spectrometer to track real-time emissions of volatile secondary oxidation products released from rapeseed oil as a result of deep-frying of potato cubes. Therefore, it was possible to observe a sudden increase of volatile organic compound (VOC) emissions caused by immersion of the food, accompanied by a sudden release of steam from a potato cube and a decrease of the oil temperature by more than 20 °C. It was possible to identify and monitor the emission of major secondary oxidation products such as saturated and unsaturated aldehydes, namely acrolein, pentanal, 2-hexenal, hexanal, 2-nonenal and 2-decenal. Each of them has an individual release characteristic. Moreover, the impact of different initial frying temperatures on release kinetics was investigated. Subsequently, it was possible to approximate the cumulative emission by a second-degree polynomial (R² ≥ 0.994). Using the proposed solution made it possible for the first time to observe the impact of the immersion of food in vegetable oil on the early emission of thermal degradation products oil.

Evaluation of glycerol core aldehydes formation in edible oils under restaurant deep frying

Glycerol core aldehydes (GCAs) are potentially toxic lipid oxidation products characterized by aldehydic acids bonded to glycerol via acyl groups. This study investigated the profile and change of GCAs in rapeseed oil (RO), high-oleic sunflower oil (HOSO) and cottonseed oil (CO) after frying chicken nuggets (CNs), fish nuggets (FNs) and French fries (FFs) for 60 h in real restaurant frying systems. Three GCAs (8-oxo, 9-oxo, and 10-oxo-8) were identified, with the GCAs (9-oxo) accounting for the highest value (60%), followed by GCAs (10-oxo-8) and GCAs (8-oxo). The total GCAs increased from 1.12 to 2.02 mg/g with frying time from 0 to 60 h in RO used for frying FNs. The FN frying systems produced the largest amount of GCAs, whereas the FF frying systems produced the least. RO contained more GCAs than CO and HOSO owing to its higher unsaturated fatty acid content (91.81%). Furthermore, the GCAs showed a high correlation with polymerized and oxidized products, indicating that the formation of GCAs were related to the oxidative stability of oils. These results may provide insight into the formation of GCAs and their control during frying.

Evaporation rates and pollutants emission from heated cooking oils and influencing factors

The heating of edible oils during cooking activities promotes the emissions of pollutants that have adverse impacts on the health of humans. This study investigated the evaporative emissions of fifteen (15) commonly used cooking oils. Split-plot experimental design under the response surface methodology framework was used to study singular and interaction effects of influencing parameters (temperature, volume of cooking oil and time) on cooking oil evaporation rate and pollutants emissions (i.e. Particulate matter of aerodynamic diameter ≤1 μm (PM_1.0); ≤2.5 μm (PM_2.5); ≤10 μm (PM₁₀); Total Suspended Particulate (TSP); Total Volatile Organic Compounds -TVOCs, and Carbon Monoxide- CO) on a groundnut oil sample that served as a case study. Obtained values of density, viscosity, kinematic viscosity, smoke, flash and fire points were; 873-917 kg/m³; 1.12-9.7 kg/ms; 2.4-3.4 m²/s; 96 -100 °C; 124-179 °C and 142-186 °C, respectively. The role of temperature as the most significant parameter influencing the rate of evaporative emissions was established. Evaporation rate and pollutants emission from unrefined samples were the highest. The restricted maximum likelihood (REML) analysis results suggested a strong relationship between the actual values and the predicted values as R-squared values obtained were greater than 0.8 for all the responses. These results suggest that minimal rates of evaporation and pollutants emission from heating cooking oils can be achieved with a high volume of the cooking oil at moderate temperature levels.

Effect of Frying on Physicochemical and Sensory Properties of Potato Chips Fried in Palm Oil Supplemented with Thyme and Rosemary Extracts

Quality parameters of potato chips (flat and serrated) fried either in palm oil (PO) alone or containing natural (thyme (TPO) and rosemary (RPO) extracts) and synthetic BHT (BPO) antioxidants were evaluated during storage period. The free fatty acid and peroxide values of chips fried in PO (control) were found between 0.18 and 0.21% to 1.00 and 1.04 meqO₂/kg during the first storage month, respectively. However, these values were 0.07-0.10% and 0.55-0.90 meqO₂/kg for chips fried in TPO, respectively. The water contents increased when storage time increased from 1 to 7 month and their values changed between 0.49 and 1.95% (flat potato chips in BPO) and between 0.88 and 1.24% (serrated potato chips in TPO). The total trans-fat contents were 0.13% (serrated potato chips in BPO) and 0.35% (both flat and serrated potato chips in PO) at the start of storage. The total trans-fat content after 7 months were 0.13% (PO fried flat and serrated potato chips) and 0.17% (serrated potato chips fried in BPO, TPO and RPO). The acrylamide contents varied between 152 (serrated potato chips in PO) and 540 µg/kg (flat potato chips fried in RPO) at the beginning of storage. However, the acrylamide contents changed during 7^th storage month and ranged from 182 (serrated potato chips in PO) to 518 µg/kg (flat potato chips in RPO). Among fatty acids, while palmitic acid are determined between 37.14 (flat chips in PO) and 41.60% (serrated chips in TPO), oleic acid varied between 30.0 (flat chips in RPO) and 33.00% (serrated chips in PO). Sensory evaluation showed that PO containing antioxidants showed better consumer preference for potato chips until the end of storage.

Feasibility of using bed filters packed with rice-straw-based activated carbon and selected biomass waste for the control of frying fume exhaust

Open-air burning of rice straw (RS) on sites after harvesting produces tremendous amounts of air pollutants in Southeast Asia. Additionally, cooking oil smoke (COS) from high-temperature frying is classified as "Probably carcinogenic to humans" (Group 2A) by the International Agency for Research on Cancer. To mitigate the air pollution from COS, RS was recycled to prepare activated carbon (AC), which was used as a bed filter (BF) packing material for COS removal, and to our best knowledge, this study is the first one. Besides, a negative air ionizer (NAI) was firstly utilized to enhance the removal efficiency (η) of COS particles. Other biomass waste, including tea leaves (TL), wood dust (WD), rice hulls (RH), and coffee grounds (CG), were also used as packing materials for comparison. Specific surface area and pore volume of the packing materials were determined by nitrogen adsorption/desorption isothermal. Laser airborne particle counters and volatile organic compound (VOC) monitors (photoionization detector) were utilized for real-time recording of the particle and VOC concentration of COS. Economic assessments for the control of COS was also conducted. For submicron particles, the removal efficiency of the BFs ranged from 0 to 98% and the AC filter had the highest quality factor. The NAI remarkably enhanced the η value and filter quality factor. For the removal of particles larger than 2.5 μm, all BFs had η > 96%. The removal efficiency of volatile organic compounds (VOCs) (ηVOC) of the test BFs ranged from 18.22 to 90.8%. The AC filter had the largest pore volume (0.432 cm3/g) and surface area (877 m2/g) among all packing materials, causing this filter to have the highest ηVOC and adsorption capacity (over 28.3 mg-VOCs/g-AC). The annual operating costs of the TL, WD, RH, CG, and AC filters were 319.4, 23.3, 29.1, 189.4, and 62.9 US$, respectively. Therefore, using RS to prepare an AC bed filter for the removal of COS is a practical and sustainable strategy for COS control.

Evaluation of the effects of aldehydes on association colloid properties and oxidative stability in bulk oils

The effects of amphiphilic aldehydes, including propanal, hexanal, and nonanal, on the critical micelle concentration (CMC) of phospholipids, moisture content, and oxidative stability in soybean oil were evaluated. The selected aldehydes are typical secondary oxidation products from unsaturated fatty acids. Moisture content increased as aldehydes were added to soybean oil during thermal oxidation at a storage temperature of 50 or 100 °C. The CMC of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) increased as propanal and hexanal were added, whereas nonanal decreased the CMC of DOPC, which implies that aldehydes participate in forming association colloids in bulk oils. The addition of aldehydes increased the rates of lipid oxidation significantly in both 50 and 100 °C treatments (p < 0.05), with the effect being more evident in oils treated at 50 °C than at 100 °C. Therefore, aldehydes formed from lipid oxidation affected the association colloidal structures and oxidative stability in a bulk oil matrix.

Determination of Physicochemical and Functional Properties of Coconut Oil by Incorporating Bioactive Compounds in Selected Spices

Lipid oxidation has been identified as a major deterioration process of vegetable oils, which leads to the production of primary and secondary oxidative compounds that are harmful to human health. Oleoresins of ginger, garlic, nutmeg, pepper, cloves, and cinnamon were extracted and incorporated into coconut oil, and change occurrence on physicochemical properties, thermal stability, shelf life, and antioxidant activity was monitored against the same properties of pure coconut oil. Lipid oxidation was assessed in terms of the free fatty acid level and peroxide value. For the comparison purpose, another oil sample was prepared by incorporating vitamin E too. Results revealed that both peroxide value and FFA of pure and flavored coconut oil samples after a one-week storage period were 3.989 ± 0.006 and 3.626 ± 0.002 mEq/kg and 0.646 ± 0.001 and 0.604 ± 0.002 (%), respectively. Saponification value, iodine value, smoke point, and the flashpoint of flavored oil were decreased while increasing the viscosity during storage. The highest phenolic content and DPPH free radical scavenging activity were found in flavored coconut oil. Since spices containing antioxidants, the thermal stability of flavored oil was better than that of pure coconut oil. Both oleoresins and vitamin E-incorporated samples showed the same pattern of increment of FFA and peroxide value during storage; however, those increments were slower than those of pure coconut oil.

Repeatedly heated mix vegetable oils-induced atherosclerosis and effects of Murraya koenigii

Background

Statins are considered as standard drugs to control cholesterol levels, but their use is also associated with renal hypertrophy, hemorrhagic stroke, hepatomegaly, and myopathy. Murraya koenigii is an herb that is used in traditional cuisine and as a medicine in South Asia. Here we assessed the antidyslipidemic and antiatherosclerotic effects of this spice in repeated heated mix vegetable oils (RHMVO)-induced atherosclerotic models.

Methods

Aqueous extract of M. koenigii leaves (Mk LE) was prepared and its phytoconstituents were determined. Rabbits were divided into 5 groups (n = 10). Except for the control group, all the other four groups were treated with RHMVO for 16 weeks (dose = 2 ml/kg/day) to induce dyslipidemia and atherosclerosis. These groups were further treated for 10 weeks either with 300 and 500 mg/kg/day Mk LE, lovastatin, RHMVO, or left untreated. Body and organ weights were measured along with oxidative stress and tissue damage parameters. Lipid profile and hepatic function markers were studied. Atheroma measurement and histopathological examination were also performed in control and treated groups.

Results

Mk LE significantly (p < 0.05) attenuated RHMVO-induced dyslipidemia and atheroma formation. Furthermore, fat accumulation and lipid peroxidation in hepatic tissues were reduced by Mk LE in a dose-dependent manner. Our results indicated that the antidyslipidemic effects of Mk LE in 500 mg/kg/day dose were comparable to lovastatin. Additionally, oxidative stress markers were reduced much more significantly in Mk LE-500 than in the statin group (p < 0.05).

Conclusions

This study recommends Mk LE as a potent antioxidant and lipid-lowering natural medicine that can attenuate the RHMVO-induced atherosclerotic in optimal doses and duration. Therefore, Mk LE can be accessible, cheap, and free of adverse effects alternate to statins.

Fermented black barley ameliorates lung injury induced by cooking oil fumes via antioxidant activity and regulation of the intestinal microbiome in mice

To investigate the effect of fermented black barley on cooking oil fume (COF)-induced lung injury, male ICR mice were randomized into five groups: normal control (NC), fermented black barley treatment (NF), COF exposure (O), COF + fermented black barley treatment (OF) and COF + Lactobacillus treatment (OL). The exposure of mice to COF was performed for 5 min per day and 4 days per week for a total of 9 weeks, and the mice in the OF, NF and OL groups were administered fermented black barley or Lactobacillus continuously for 9 weeks (1 mL/100 g). Our results showed that the gamma-aminobutyric acid (GABA), total phenolic, and flavonoid contents significantly increased after fermentation (P < 0.01). In addition, fermented black barley significantly increased SOD activity in the lung tissue, decreased the wet pulmonary coefficient, inhibited the reduction of microbial diversity and richness, and upregulated genes involved in cilium assembly and the cilium axoneme. These findings support the notion that fermented black barley can ameliorate COF-induced lung injury in mice.

Association of long-term consumption of repeatedly heated mix vegetable oils in different doses and hepatic toxicity through fat accumulation

BACKGROUND

Hepatic diseases are one of the chief reasons for worldwide morbidity and mortality. The increased incidence in Asian countries is driving researchers to explore preventive ways from nature. It is more practical to go with healthy routine edibles like vegetable oils to avoid environmental and chemical hepatic injuries. With the use of thermally oxidized oils overproduction of reactive oxygen species (ROS) with overwhelmed cellular antioxidants defense system results in oxidative stress, the known cause of cardiovascular diseases (CVDs), cancers and neurodegenerative disorders. Little is investigated about the effect of daily used oxidized cooking oils on hepatic function changes with oxidative stress especially in the animal model that mimics the human situation.

METHODS

In this study, healthy adult male rabbits of local strain were divided into 4 groups (n = 12). First, two sets of rabbits were treated with 1 and 2 ml/kg/day of repeatedly heated mix vegetable oils (RHMVO) respectively. The third set of rabbits was given 1 ml/kg/day of single time heated mix vegetable oils (STHMVO) and the fourth set of rabbits served as controls and fed with normal rabbit diet to for 16 weeks. Serum liver function markers including total-protein, albumin, serum glutamic-oxaloacetic transaminase (SGOT), serum glutamic-pyruvic transaminase (SGPT) and alkaline phosphatase (ALP) along with the activity of hepatic antioxidant-enzymes including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and malondialdehyde (MDA) for lipid peroxidation were compared among different groups of rabbits. Histopathological examination was performed for all four groups.

RESULTS

Significantly (p < 0.05) elevated hepatic enzymes and MDA levels, with lower total protein, serum albumin, GPx, SOD and CAT levels were found in high and low doses RHMVO treated groups, in comparison to control. In the STHMVO group, all mentioned markers were insignificantly changed. Accumulation of liver fat in low and high dose oil-treated groups was further confirmed under the microscopic examination of liver tissues, presented significant fat accumulation in liver tissues, in addition, 40-60% increased oxidative stress compared to control, in a dose-dependent manner.

CONCLUSIONS

These results conclude that consumption of thermally oxidized mix vegetable oils for longer duration can impair the liver function and destroy its histological structure significantly through fat accumulation and oxidative stress both in high as well as low doses.

Mechanistic studies of inhibition on acrolein by myricetin

Acrolein (ACR) is an unsaturated aldehyde with high activity and toxicity and is produced in vivo and in food. This study investigated the impact of B-ring structure on the trapping of ACR by flavonols and the trapping mechanism and efficacy of ACR by myricetin. Galangin, kaempferol, quercetin, and myricetin, which possess the same A- and C-ring but different numbers of -OH groups on the B-ring, were selected for this study. Our results suggested that increasing the number of -OH groups on the B-ring can enhance the ACR trapping efficacy of flavonol and myrectin was identified as the most active flavonol. The adducts of myricetin with ACR under different ratios and incubation times were analyzed using LC-MS/MS. We also purified and identified the major mono- and di-ACR-myricetin adducts. Furthermore, myricetin could dose-dependently inhibit the formation of ACR in cookies through the formation of mono- and di-ACR adducts.

Volatile compound profiling from soybean oil in the heating process

Soybean oil heating or cooking is a very complicated process. In order to better understand the composition of the volatile compounds from soybean oil during heating process, volatile profiling was carried out through vacuum-assisted headspace solid-phase microextraction combined with GC-MS. As a result, a total of 72 volatile compounds were detected and identified during this process, including aldehydes (27), alcohols (14), ketones (10), furans (6), aromatic compounds (9), acids, and esters (6). And the forming temperature of each volatile was determined. Results show most of volatile aldehydes and alcohols were formed at 120°C leading to release off-flavor largely, which was considered as a critical temperature point for the formation of soybean oil flavor during the whole heating process. Meanwhile, ketones and furans were formed at 150°C, and acids were detected at 180°C. The content of most volatile compounds increased significantly with the temperature raised. Simultaneously, results of principal component analysis demonstrate that flavor characteristics of soybean oil have a big difference between higher and lower temperature in the heating process.

Fast and sensitive detection of acrolein in environmental water samples without derivatization using liquid chromatography tandem mass spectrometry

A fast and sensitive SPE-LC-MS/MS method for the determination of acrolein in environmental water samples using activated charcoal as SPE adsorbent was developed. The novelty of this study consists in acrolein extraction, separation and detection without the need of a derivatization process. Physicochemical properties of acrolein, such as low molecular weight and high polarity represent real challenges for extraction, separation, and detection of this pollutant using SPE-LC-MS/MS. These were addressed by choosing a suitable chromatographic column which ensures a good peak symmetry and retention for the analyte, as well as the choice of SPE adsorbent suitable for retaining very polar compounds like acrolein from the aqueous matrix. The chromatographic column was a Synergi Fusion RP (150 × 2.0 mm, 4.0 μm) with a C18 stationary phase modified with polar embedded amide groups. Activated charcoal adsorbent used as SPE extraction media was able to extract efficiently highly polar molecules such as acrolein and ¹³C₃-acrylamide (internal standard) from water samples. Using this method, the obtained extraction recovery for acrolein was 88% at a 50 ng/L concentration level. Overall method quantitation limit (LOQ) for acrolein in water was established at 3.8 ng/L. The newly developed SPE-LC-MS/MS method was successfully applied to detect acrolein occurrence in wastewater and drinking water samples. Acrolein level in these samples ranged from LOQ to 122 ng/L.

Quantification of the impact of cooking processes on indoor concentrations of volatile organic species and primary and secondary organic aerosols

Cooking is recognized as an important source of particulate pollution in indoor and outdoor environments. We conducted more than 100 individual experiments to characterize the particulate and non-methane organic gas emissions from various cooking processes, their reaction rates, and their secondary organic aerosol yields. We used this emission data to develop a box model, for simulating the cooking emission concentrations in a typical European home and the indoor gas-phase reactions leading to secondary organic aerosol production. Our results suggest that about half of the indoor primary organic aerosol emission rates can be explained by cooking. Emission rates of larger and unsaturated aldehydes likely are dominated by cooking while the emission rates of terpenes are negligible. We found that cooking dominates the particulate and gas-phase air pollution in non-smoking European households exceeding 1000 μg m-3 . While frying processes are the main driver of aldehyde emissions, terpenes are mostly emitted due to the use of condiments. The secondary aerosol production is negligible with around 2 μg m-3 . Our results further show that ambient cooking organic aerosol concentrations can only be explained by super-polluters like restaurants. The model offers a comprehensive framework for identifying the main parameters controlling indoor gas- and particle-phase concentrations.

Analysis of Volatile Compounds from Wheat Flour in the Heating Process

Volatile profiling was carried out during heating through vacuum-assisted headspace solid-phase microextraction combined with gas chromatography-mass spectrometry to better understand the flavor forming mechanism of flour products. Ninety-two volatile compounds were detected and identified, including aldehydes (25), ketones (15), alcohols (9), nitrogen- and sulfur-containing compounds (6), benzene derivatives (15), furans (10), and acids and esters (12). The formation temperature of each volatile was also determined. Results showed that temperature played an important role in the formation and content of volatile compounds. In the low-temperature range (60 °C–100 °C), the flavor composition of flour was mainly composed of C6–C10 volatile aldehydes and alcohols. At temperatures exceeding 100 °C, especially at 120 °C, many long carbon chain aldehydes and alcohols, furans, acids, esters, nitrogen- and sulfur-containing compounds were formed. The formation rate of most identified volatile compounds increased during heating, especially from 90 °C to 130 °C.

Oxidation delay of sunflower oil under frying by moringa oil addition: more than just a blend

BACKGROUND

Blending Moringa oleifera oil (MOO) with other oils of recognized lower stability under prolonged frying results in oxidation delay. The present study aimed to detail the probable molecular interactions supporting these observations, using a small amount of MOO (20%) and sunflower oil (SFO; 80%) under domestic deep-frying conditions (intermittent frying of fresh potatoes, 180 °C, 2 × 90 min day^-1 , 5 days).

RESULTS

Blending 20% MOO with SFO resulted in a significantly lower formation of polymers (<43 to 85%) and oxidized triglycerides (<20 to 60%), a 25-60% reduction in p-anisidine value and total volatile aldehydes, particularly alkadienals, and a better performance than the one predicted from the oils' mass ratio. Blending was particularly effective in vitamin E and antioxidant activity preservation, probably from interaction with some MOO components such as sterols and vitamin E, while carotenoids and phenolics do not seem to be implicated.

CONCLUSIONS

These results provide an interesting use for MOO, improving the thermo-oxidative performance of SFO while providing nutritional benefits and lowering the formation of toxic compounds during prolonged deep-frying. © 2019 Society of Chemical Industry.

Changes in the volatile profile, fatty acid composition and other markers of lipid oxidation of six different vegetable oils during short-term deep-frying

Oil deterioration during deep-frying influences the quality of fried foods to a great extent. In this study, the frying performance of six vegetable oils, i.e., hemp, lupin, oat, rapeseed, soy, and sunflower, was evaluated following short-term (60 min) deep-frying of French fries at 180 °C. The frying oils were investigated for fatty acid profile, volatile compound composition, and parameters of oxidative stability, such as iodine, peroxide, and p-anisidine values. The examination showed that the content of ƩPUFA in hemp oil decreased significantly (p < 0.05) after 60 min of deep-frying, although the degree of change was relatively small (close to 1.5%). Similarly, soy oil presented a fatty acid profile prone to oxidation, and generated the highest level of peroxides at the end of the thermal treatment (PV = 16.6 ± 2.3 mEq O₂ kg^-1). As for the volatile compound composition of the oils, sunflower oil was extensively affected by the deep-frying treatment with a significant decrease (p > 0.05) in total terpenes, accompanied by a considerable rise in total aldehydes. Oppositely, the proportions of MUFA and PUFA of lupin and oat oils remained stable (p > 0.05) during the short-term deep-frying, indicating high stability of these oils. The research provided new data for evaluating the suitability of these oils for household food preparations.

Phenolics and Antioxidant Capacity of Pitted Olive Pomace Affected by Three Drying Technologies

This study investigated drum-drying's ability to produce dried food-grade olive pomace as a potential food ingredient that is more nutritionally dense than its freeze-dried and hot-air dried counterparts. The pits and skin were removed from fresh olive pomace, and the remaining pulp was dried to <5% moisture through freeze-drying, hot-air drying, and drum-drying at two rotational speeds. The drying treatments had no significant (P ≤ 0.05) effect on the olive pomace's fat or dietary fiber contents but did increase the L^* , a^* , and b^* color parameter values. Although all the drying treatments significantly (P ≤ 0.05) decreased the fresh olive pomace's antioxidant capacity, drum-drying preserved the olive pomace's antioxidant capacity significantly (P ≤ 0.05) better than freeze-drying and hot-air drying. The drum-dried samples had concentrations of caffeic acid and verbascoside that were significantly (P ≤ 0.05) higher than the other dried pomace samples and were not significantly (P ≤ 0.05) different from the fresh pomace. The drum-dried olive pomace contained concentrations of hydroxytyrosol, tyrosol, vanillic acid, luteolin-7-glucoside, and rutin that were not significantly (P ≤ 0.05) different from the dried sample with the highest concentration of each respective phenolic compound. No oleuropein was found in the fresh or dried olive pomace. The results of this study show that drum-drying is an energy efficient method for converting olive pomace into a stable food-grade supplement that preserves its high phenolic, antioxidant, and dietary fiber contents to potentially benefit human health when incorporated into food or supplement products. PRACTICAL APPLICATION: Pitting and drying converts the olive pomace into a stable form that is free of physical hazards and could be incorporated into food products to increase their nutritional quality through olive pomaces' high fiber, antioxidant, and phenolic contents. Drum-drying allows food-grade olive pomace to retain higher amounts of beneficial soluble phenolics and a higher antioxidant capacity than conventional drying methods, thus furthering olive pomace's potential valorization as a food ingredient.

Airflow obstruction among ever-employed U.S. adults aged 18-79 years by industry and occupation: NHANES 2007-2008 to 2011-2012

INTRODUCTION

This study estimated the prevalence of spirometry-defined airflow obstruction by industry and occupation and chronic obstructive pulmonary disease (COPD) among ever-employed U.S. adults.

METHODS

Data came from the National Health and Nutrition Examination Survey (NHANES) 2007-2008 to 2011-2012, a nationally representative study of the non-institutionalized civilian U.S.

POPULATION

Data on respondent's current and/or longest held job were used to create prevalence estimates and adjusted prevalence odds ratios (PORs) for airflow obstruction and COPD.

RESULTS

Among ever-employed U.S. adults, airflow obstruction prevalence was 12.40% and COPD was 3.47%. High airflow obstruction prevalence and significant PORs were reported in mining; manufacturing; construction; and services to buildings industries as well as extraction; bookbinders, prepress, and printing; installers and repairers; and construction occupations.

CONCLUSION

Prevalence of airflow obstruction varies by industry and occupation. Industries and occupations with increased risk were identified using the most current NHANES data including detailed occupations and spirometry.

Environmental Aldehyde Sources and the Health Implications of Exposure

Aldehydes, which are present within the air as well as food and beverage sources, are highly reactive molecules that can be cytotoxic, mutagenic, and carcinogenic. To prevent harm from reactive aldehyde exposure, the enzyme aldehyde dehydrogenase 2 (ALDH2) metabolizes reactive aldehydes to a less toxic form. However, the genetic variant of ALDH2, ALDH2*2, significantly reduces the ability to metabolize reactive aldehydes in humans. Therefore, frequent environmental aldehyde exposure, coupled with inefficient aldehyde metabolism, could potentially lead to an increased health risk for diseases such as cancer or cardiovascular disease.Here, we discuss the environmental sources of reactive aldehydes and the potential health implications particularly for those with an ALDH2*2 genetic variant. We also suggest when considering the ALDH2*2 genetic variant the safety limits of reactive aldehyde exposure may have to be reevaluated. Moreover, the ALDH2*2 genetic variant can also be used as an example for how to implement precision medicine in the field of environmental health sciences.

Characterization of canola oil extracted by different methods using fluorescence spectroscopy

The potential of fluorescence spectroscopy has been utilized for the characterization of three types of canola oil samples: the first type was obtained by dissolving its seeds in hexane solvent, the second by cold press method, and the third from eight commercial brands. Fluorescence spectra from all samples have been acquired by using excitation wavelengths from 280 to 420 nm with step of 10 nm to investigate their valuable ingredients. The emission bands at 375, 525 and 673 nm that represent vitamin E/beta-carotene and chlorophyll, are present only in canola oil samples extracted by chemical and cold press methods and absolutely absent from all commercial brands. The emission band at 440 nm appearing only in the commercial oil brands, is assigned to oxidized products of isomers of vitamin E and fatty acids. In addition, the effect of temperature on the canola oil extracted by cold press method has been investigated which showed that up to 180 ^oC it does not lose much of its natural molecular composition. However, it showed a trend of thermal oxidation with rise of temperature.

Impact of potatoes deep-frying on common monounsaturated-rich vegetable oils: a comparative study

Aiming to distinguish the nutritional and safety impacts on consumer's health of prolonged frying with vegetable oils rich in monounsaturated fatty acids (MUFA), namely peanut oil (PO), canola oil (CO) and extra virgin olive oil (EVOO), a domestic deep-frying assay using fresh potatoes was implemented (175 °C, 8 h per day, up to 28 h). Based on a total polar compounds (TPC) degradation limit of 25%, PO and CO enabled 18-20 h of frying, while EVOO allowed significantly higher frying hours (> 28 h). Despite the non-significant variations in oxidized triglycerides contents observed through time, and loss of all major antioxidants during the first 8 to 12 h of frying, PO showed statistically higher amounts of conjugated dienes (27 at 20 h; against 19 in CO and 17 in EVOO) and CO of anisidine value (252 at 20 h; against 209 in PO and 100 in EVOO), indicative of different oxidation patters. This was corroborated with the analysis of major volatiles, with PO and CO being statistically richer in alkenals and alkadienals, respectively. Therefore, despite the MUFA predominance, differences in their unsaturation profile impact on the type and amount of degradations products formed under prolonged frying and consequently on consumer's health. As to EVOO use for prolonged frying, despite its increased resistance to oxidation and lower risk of formation of unhealthy volatiles, it loses its pool of natural bioactive compounds in the first hours of frying.