Oil matrix effects on plasma exposure and urinary excretion of phenolic compounds from tomato sauces: Evidence from a human pilot study

Field-Deployable Determinations of Peroxide Index and Total Phenolic Content in Olive Oil Using a Promising Portable Sensor System

Useful information about the oxidative stability of a virgin olive oil in terms of oxidation products and antioxidant compounds can be obtained by analyzing the peroxide index (PI) and total phenolic content (TPC), respectively. These quality parameters are usually determined in a chemical laboratory using expensive equipment, toxic solvents, and well-trained personnel. This paper presents a novel portable sensor system for in the field and rapid determination of PI and TPC that is particularly suited in the case of small production environments that cannot afford an internal laboratory for quality control analysis. The system is small, can be powered by both USB ports and batteries, is easy to operate, and integrates a Bluetooth module for wireless data transmission. It estimates the PI and TPC in olive oil from the measurement of the optical attenuation of an emulsion between a reagent and the sample under test. The system has been tested on a set of 12 olive oil samples (eight for calibration and four for validation), and the results have shown how the considered parameters can be estimated with good accuracy. The maximum deviation from the results obtained with the reference analytical techniques is 4.7 meq O₂/kg in the case of PI and 45.3 ppm in the case of TPC for the calibration set, while it is 14.8 meq O₂/kg in the case of PI and 55 ppm in the case of TPC for the validation set.

Oil matrix modulates the bioaccessibility of polyphenols: a study of salad dressing formulation with industrial broccoli by-products and lemon juice

BACKGROUND

The potential health-promoting effects of polyphenols depend considerably on their bioaccessibility, which is affected by the presence of other nutrients in the diet, including lipids. In this study, several salad dressing formulations were prepared using industrial broccoli by-product powder (BBP), lemon juice (LJ), and three different sources of oils (olive oil, hazelnut oil and sunflower oil) to both valorize polyphenol-rich industrial discards and also to investigate polyphenol bioaccessibility. The changes in the bioaccessibility of polyphenols from BBP and LJ were determined using the standardized in vitro digestion model.

RESULTS

Four groups of polyphenols (hydroxycinnamic acids, flavonols, flavones, and flavonones) were detected in BBP and LJ. The bioaccessibility of hydroxycinnamic acids and flavonols from BBP increased significantly in the presence of LJ and oils (0.3- to 5.8-fold), whereas there was no significant difference between formulations containing different oil types. On the other hand, the bioaccessibility of phenolic acids from LJ did not change notably after co-ingestion with BBP and oils, whereas flavonoids, including vicenin-2 and hesperidin, were found to be significantly more bioaccessible when LJ was co-ingested with BBP and oils (0.8- to 1.4-fold) (P < 0.05).

CONCLUSION

Overall, the current study highlighted that the bioaccessibility of polyphenols from BBP and LJ was modulated in the presence of an oil matrix. © 2022 Society of Chemical Industry.

A Portable Battery-Operated Sensor System for Simple and Rapid Assessment of Virgin Olive Oil Quality Grade

Virgin olive oil quality is assessed by chemical as well as sensory analysis. Two of the most important parameters that define the quality of virgin olive oils are the free acidity and the peroxide index. These chemical parameters are usually determined by manual titration procedures that must be carried out in a laboratory by trained personnel. In this paper, a portable sensor system to support the quality grade assessment of virgin olive oil is presented. The system is battery operated and characterized by small dimensions, light weight and quick measurement response (about 30 s). The working principle is based on the measurement of the electrical conductance of an emulsion between a chemical reagent and the olive oil sample. Two different chemical reagents have been investigated: (1) a hydro-alcoholic solution (HAS), made of 60% ethanol and 40% distilled water; (2) 100% distilled water (DW). Tests have been carried out on a set of 40 olive oil samples. The results have shown how, for most of the fresh virgin olive oil samples (31 samples out of 40), the free acidity can be estimated with good accuracy from the electrical conductance of the emulsion using HAS as the reagent. In the case of the full set of samples, the emulsion electrical conductance, using HAS as the reagent, is a function of both the sample free acidity as well as the compounds produced by oil oxidation, and a compensation method based on the measured electrical conductance, using DW as the reagent, has been introduced to improve the accuracy in the estimated free acidity. Tests have also been carried out on the full set of samples, using a k-nearest neighbors algorithm, to demonstrate the feasibility of olive oil classification according to the quality grade. The results have shown how measurements carried out using only the HAS reagent provide better classification accuracy than measurements carried out using both the HAS and DW reagents. The proposed system can be a low-cost alternative to standard laboratory analyses to evaluate the quality grade of virgin olive oil.

A Review of the Effects of Olive Oil-Cooking on Phenolic Compounds

The fate of phenolic compounds in oil and food during cooking vary according to the type of cooking. From a nutritional point of view, reviews largely suggest a preference for using extra-virgin olive oil at a low temperature for a short time, except for frying and microwaving, for which there appears to be no significant advantages compared to olive oil. However, due to the poorly pertinent use of terminology, the different protocols adopted in studies aimed at the same objective, the different type and quality of oils used in experiments, and the different quality and quantity of PC present in the used oils and in the studied vegetables, the evidence available is mainly contradictory. This review tries to reanalyse the main experimental reports on the fate, accessibility and bioavailability of phenolic compounds in cooking oils and cooked vegetables, by considering different cooking techniques and types of oil and foods, and distinguishing experimental findings obtained using oil alone from those in combination with vegetables. The re-analysis indicates that incomplete and contradictory observations have been published in the last few years and suggests that further research is necessary to clarify the impact of cooking techniques on the phenolic compounds in oil and vegetables during cooking, especially when considering their nutritional properties.

Effects of Breaking Methods on the Viscosity, Rheological Properties and Nutritional Value of Tomato Paste

Ultrasound-assisted processing has potential application advantages as an emerging technology for preparing tomato paste. This work explored the influence of ultrasound break at 22 °C (US-Break-22) and 65 °C (US-Break-65) on the viscosity, rheological properties and nutritional values of newly prepared tomato paste, compared with traditional thermal break at 65 °C (Break-65) and 90 °C (Break-90). Results showed that the US-Break-65 paste had the largest apparent viscosity, yield stress, consistency coefficient, solid-like nature, and large amplitude oscillatory shear behavior, followed by the US-Break-22 paste, Break-90 paste, and Break-65 paste. Based on the results of the pectin-related enzymes, particle size, and serum pectin of the pastes, it was revealed that the above-mentioned properties were mainly determined by the particle size and pectin content in their serum. The level of ascorbic acid followed the order of US-Break-22 paste > US-Break-65 paste > Break-65 paste > Break-90 paste. The level of total carotenoids followed the order of US-Break-22 paste ≈ US-Break-65 paste > Break-90 paste ≈ Break-65 paste. The level of total cis-carotenoids followed the order of US-Break-65 paste > US-Break-22 paste > Break-90 paste > Break-65 paste. The level of phenolics and antioxidant activities followed the same order of US-Break-22 paste > US-Break-65 paste > Break-90 paste > Break-65 paste. Overall, the viscosity, rheological properties and nutritional values of the tomato pastes prepared by US-Break-65 and US-Break-22 were significantly higher than those prepared by Break-65 and Break-90. Therefore, ultrasound assisted processing can prepare high quality tomato paste and can be widely implemented in the tomato paste processing industry.

In vitro gastrointestinal digestion and colonic fermentation of tomato (Solanum lycopersicum L.) and husk tomato (Physalis ixocarpa Brot.): Phenolic compounds released and bioconverted by gut microbiota

Two of the most important Mexican plant-foods are tomato (Solanum lycopersicum L.) and husk tomato (Physalis ixocarpa Brot.). In this study three objectives were followed: i) to evaluate the bioaccessible phenolic compounds (PC) in T and HT during upper gastrointestinal digestion, ii) to in vitro ferment the indigestible fractions of the samples to evaluate the short-chain fatty acids (SCFA) production, iii) the microbial metabolites, bioconverted PC and volatile organic compounds (VOCs) generated during the fermentation. Vanillic acid was the most bioaccessible PC and after 48 h, 3-hydroxyphenylacetic acid was the most abundant microbial metabolite identified in both samples. The identification of VOCs belonging to terpenes (and derivatives) group in T and HT can be product of the microbial metabolism of carotenoids. The study shows new knowledge of the in vitro intestinal digestion and fermentation of T and HT final compounds with biological potential which should be evaluated in further studies.

The Nutraceutical Properties of "Pizza Napoletana Marinara TSG" a Traditional Food Rich in Bioaccessible Antioxidants

Italian gastronomy experiences have ever-enhancing fame around the world. It is due to the linkage between taste and salubriousness commonly related to Mediterranean foods. The market proposes many types of pizza to suit all palates. The antioxidant potential of the “Pizza Napoletana marinara” included in the register of traditional specialties guaranteed (TSG) was determined in this work. ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) method evaluated the antioxidant activity of the pizza homogenized. In vitro digestion models estimated the intestinal and gastric bioaccessibility of the main antioxidant compounds (lycopene and phenolics). To our knowledge, this is the first study to provide the content, antioxidant potential, and bioaccessibility of the antioxidants (polyphenols and lycopene) contained in the traditional pizza “marinara TSG”. Our results showed that the “Pizza Napoletana marinara” had polyphenols concentration, lycopene level, antioxidant activity, and bioaccessibility of phenolic compounds and lycopene better than other similar pizzas. They confirmed the nutritional importance of traditional preparations and established the nutraceutical potential of “pizza marinara TSG” as a food rich in bio-accessible antioxidants.

Using Extra Virgin Olive Oil to Cook Vegetables Enhances Polyphenol and Carotenoid Extractability: A Study Applying the sofrito Technique

Olive oil is the main source of fat in the Mediterranean diet and the most frequently used ingredient in Mediterranean cuisine. Cooking with olive oil has been attracting attention because it can act as a food excipient, thereby increasing the bioaccessibility and bioavailability of ingested bioactive compounds. The aim of this study was to understand the effect of cooking with olive oil on the bioactive components in other ingredients (tomato, onion, and garlic) of sofrito sauce, a representative model of Mediterranean cuisine. After the cooking process, polyphenols from tomato, onion, and garlic were detected in the olive oil, especially naringenin, ferulic acid, and quercetin, as well as a high content of carotenoid Z-isomers, which are more bioavailable than the E-isomers. Therefore, traditional Mediterranean cuisine could play an important role in the health-improving effects of the Mediterranean diet.

Acute Effect of a Single Dose of Tomato Sofrito on Plasmatic Inflammatory Biomarkers in Healthy Men

Sofrito is a Mediterranean tomato-based sauce that typically also contains olive oil, onion, and garlic. The preparation of sofrito modifies the bioactive compounds (carotenoids and polyphenols) in the ingredients to more bioavailable forms, promoting cis-lycopene formation and polyphenol bioaccessibility. To evaluate the health benefits of this cooking technique, the effect of consuming an acute dose of sofrito on the inflammatory status was studied. In a clinical trial, 22 healthy male subjects consumed a single dose of sofrito (240 g/70 kg) after three days without ingesting any tomato products and following a low-antioxidant diet the day before the intervention. Plasma carotenoids and total polyphenol excretion (TPE) were evaluated, as well as the inflammatory biomarkers C-reactive protein (CRP), interleukin-6 (IL-6), interleukin 1β (IL-1β) and tumor necrosis factor-α (TNF-α). After the sofrito intake, a significant decrease in CRP (p = 0.010) and TNF-α (p = 0.011) was observed, but only TNF-α was inversely correlated with an increase in TPE and plasma β-carotene (not the major carotenoid, lycopene). The positive health effects of this tomato-based product may be attributed not only to lycopene, but to the bioactive compounds of all the ingredients.

Wine-Derived Phenolic Metabolites in the Digestive and Brain Function

Wine, and specifically red wine, is a beverage with a great chemical complexity comprising a particular combination of phenolic compounds which are directly associated with its health-promoting properties. Wine polyphenols could induce changes in the composition of intestinal microbiota that would affect the production of physiologically active phenolic metabolites modifying the content and phenolic profile at the systemic level. In addition, in the human population, it seems that different “metabotypes”, or patterns of metabolizing wine polyphenols, exist, which would be reflected in the different biological fluids (i.e., plasma, urine and feces) and tissues of the human body. Moreover, wine polyphenols might change the composition of oral microbiota by an antimicrobial action and/or by inhibition of the adhesion of pathogens to oral cells, thus contributing to the maintenance of oral health. In turn, polyphenols and/or its metabolites could have a direct action on brain function, by positively affecting signaling routes involved in stress-induced neuronal response, as well as by preventing neuroticism-like disorders (i.e., anxiety and depression) through anti-inflammatory and epigenetic mechanisms. All of this would condition the positive effects on health derived from moderate wine consumption. This paper reviews all these topics, which are directly related with the effects of wine polyphenols at both digestive and brain level. Further progresses expected in the coming years in these fields are also discussed.

Influence of omega-3 PUFAs on the metabolism of proanthocyanidins in rats

Studies of the bioavailability of proanthocyanidins usually consider them independently of other dietary constituents, while there is a tendency in the field of functional foods towards the combination of different bioactive compounds in a single product. This study examined the long-term effects of ω-3 polyunsaturated fatty acids of marine origin on the metabolic fate of grape proanthocyanidins. For this, female adult Wistar-Kyoto rats were fed (18weeks) with a standard diet supplemented or not with eicosapentaenoic acid/docosahexaenoic acid (1:1, 16.6g/kg feed), proanthocyanidin-rich grape seed extract (0.8g/kg feed) or both. A total of 39 microbial-derived metabolites and 16 conjugated metabolites were detected by HPLC-MS/MS either in urine or in the aqueous fraction of feces. An unexpected significant increase in many proanthocyanidin metabolites in urine and feces was observed in the group supplemented with ω-3 polyunsaturated fatty acids group as compared to the animals fed a standard diet, which contains a small amount of polyphenols. However, proanthocyanidin metabolites in rats given ω-3 polyunsaturated fatty acids and grape seed extract did not significantly differ from those in the group supplemented only with grape seed extract. It was concluded that ω-3 polyunsaturated fatty acids collaborate in the metabolism of polyphenols when present at low doses in the feed matrix, while the capacity of ω-3 polyunsaturated fatty acids to induce microbiota transformations when proanthocyanidins are present at high doses is not relevant compared to that of polyphenols themselves.

Bioavailability of tomato polyphenols is enhanced by processing and fat addition: Evidence from a randomized feeding trial

SCOPE

Tomato contains a variety of phenolics associated with health-promoting properties. However, the effects of processing and the addition of oil during tomato sauce preparation on microbial metabolism of phenolics in the small intestine are still unclear.

METHODS AND RESULTS

An open, controlled, randomized, and crossover feeding trial with 40 healthy volunteers was carried out to analyze the metabolites in plasma and urine after the consumption of tomato and tomato sauces, with tomato sauce enriched with refined olive oil (ROOE) and without refined olive oil (oil-free: OF). Ten phenolics in plasma and 93 metabolites in urine were quantified. Processing tomatoes into sauce enhanced the bioavailability of flavanones, flavanols, and some hydroxycinnamic acids, as reflected by the increase in the area under the plasma concentration versus time curve. An increase in their plasma half-life was also observed, particularly after ingestion of ROOE, possibly favored by enterohepatic circulation. A wide variety of gut microbial metabolites was also detected, namely flavanones, hydroxycinnamic acids, flavonols, hydroxyphenylpropanoic acids, hydroxyphenylacetic acids, and hydroxybenzoic acids.

CONCLUSIONS

Flavanones and flavonols in ROOE presented higher bioavailability, suggesting that the processing undergone by the raw tomato improved their absorption.

Tomato Sauce Enriched with Olive Oil Exerts Greater Effects on Cardiovascular Disease Risk Factors than Raw Tomato and Tomato Sauce: A Randomized Trial

Epidemiological studies have observed a negative association between tomato intake and the incidence of cardiovascular disease. As tomato sauces are usually cooked with the addition of oil, some studies have pointed out that both processes may increase the bioavailability of the bioactive compounds. However, the effect of consumption of raw tomatoes and tomato sauces on inflammation biomarkers and adhesion molecules related to atherosclerosis remains unknown. The aim of this study was to test the postprandial effects of a single dose of raw tomatoes (RT), tomato sauce (TS) and tomato sauce with refined olive oil (TSOO) on cardiovascular disease risk factors. We performed an open, prospective, randomized, cross-over, controlled feeding trial in 40 healthy subjects who randomly received: 7.0 g of RT/kg of body weight (BW), 3.5 g of TS/kg BW, 3.5 g of TSOO/Kg BW and 0.25 g of sugar solved in water/kg BW on a single occasion on four different days. Biochemical parameters and cellular and circulating inflammatory biomarkers were assessed at baseline and 6 h after each intervention. The results indicate that, compared to control intervention, a single tomato intake in any form decreased plasma total cholesterol, triglycerides and several cellular and plasma inflammatory biomarkers, and increased plasma high density lipoproteins (HDL) cholesterol and interleukine (IL) 10 concentrations. However, the changes of plasma IL-6 and vascular cell adhesion molecule-1 (VCAM-1), and lymphocyte function-associated antigen-1 (LFA-1) from T-lymphocytes and CD36 from monocytes were significantly greater after TSOO than after RT and TS interventions. We concluded that tomato intake has beneficial effects on cardiovascular risk factors, especially cooked and enriched with oil.

Effects of Drying Temperature on Antioxidant Activities of Tomato Powder and Storage Stability of Pork Patties

This study was performed to evaluate the antioxidant activity of oven-dried tomato powder (OTP) as affected by drying temperature and the effect of OTP on the product quality of pork patties. Three OTP products were obtained by drying of fresh tomato at 60, 80 and 100℃ oven until constant weight was obtained. Total phenolic content of three kinds of OTPs ranged from 1.95 to 5.94 g/100 g. The highest amount of total phenolic compound was observed in OTP dried at 100℃. Antioxidant activity of three kinds of OTPs was measured by 1,1-diphenyl-2-pycrylhydrazyl (DPPH)-radical scavenging activity, iron chelating ability, reducing power and measurement of lipid peroxide in linoleic acid emulsion system. In all parameters, OTP at 100℃ showed the higher antioxidant activity than other temperatures (p<0.05). Based on the model study, the physicochemical properties, and antioxidant and antimicrobial activities of pork patties containing 1% OTP were measured. Redness of pork patties were increased with the addition of OTPs (p<0.05). Thiobarbituric acid reactive substances (TBARS) values of raw pork patties containing OTPs were lower than those of control (CTL) until 7 d of storage, regardless of drying temperatures (p<0.05). Peroxide values of pork patties made with OTP (1%) were lower than those of CTL until the end of storage time (p<0.05). However, no antimicrobial activities were observed among the treatments (p>0.05). Therefore, OTPs could be used as a natural antioxidant in meat products.

Evaluation of different drying temperatures on physico-chemical and antioxidant properties of water-soluble tomato powders and on their use in pork patties

BACKGROUND

Tomato and tomato products provide various antioxidant activities, which could be changed by the processing method. This study was performed to evaluate the antioxidant activity of water-soluble tomato powder (WSTP) as affected by different oven temperatures (60, 80 and 100°C), and to evaluate the physico-chemical properties and antioxidative activities of pork patties containing these powders.

RESULTS

The contents of total phenolic compounds of WSTP ranged from 22.2 to 69.6 g kg(-1) dry matter. The antioxidant activities increased significantly with increasing drying temperatures (P < 0.05). The physico-chemical properties of pork patties containing tomato powders were also evaluated. WSTP at 100°C showed the highest redness value compared to those dried at 60 and 80°C. Lipid oxidation of pork patties was retarded by 7 days with the addition of WSTP. In particular, pork patties containing WSTP showed antimicrobial activity at 14 days of refrigerated storage, regardless of drying temperatures.

CONCLUSION

WSTP, especially prepared at 100°C, could be used as a natural antioxidant and antimicrobial agent in meat products.

Absorption and disposition of naringenin and quercetin after simultaneous administration via intestinal perfusion in mice

As common constituents of vegetables, naringenin and quercetin are ingested together; for a clearer understanding of their bioavailability it is insightful to study them together.

Sensitive and Rapid UHPLC-MS/MS for the Analysis of Tomato Phenolics in Human Biological Samples

An UHPLC-MS/MS method for the quantification of tomato phenolic metabolites in human fluids was optimized and validated, and then applied in a pilot dietary intervention study with healthy volunteers. A 5-fold gain in speed (3.5 min of total run); 7-fold increase in MS sensitivity and 2-fold greater efficiency (50% peak width reduction) were observed when comparing the proposed method with the reference-quality HPLC-MS/MS system, whose assay performance has been previously documented. The UHPLC-MS/MS method led to an overall improvement in the limits of detection (LOD) and quantification (LOQ) for all the phenolic compounds studied. The recoveries ranged between 68% and 100% in urine and 61% and 100% in plasma. The accuracy; intra- and interday precision; and stability met with the acceptance criteria of the AOAC International norms. Due to the improvements in the analytical method; the total phenolic metabolites detected in plasma and urine in the pilot intervention study were 3 times higher than those detected by HPLC-MS/MS. Comparing with traditional methods; which require longer time of analysis; the methodology described is suitable for the analysis of phenolic compounds in a large number of plasma and urine samples in a reduced time frame.

Food Processing and the Mediterranean Diet

The benefits of the Mediterranean diet (MD) for protecting against chronic disorders such as cardiovascular disease are usually attributed to high consumption of certain food groups such as vegetables, and low consumption of other food groups such as meat. The influence of food processing techniques such as food preparation and cooking on the nutrient composition and nutritional value of these foods is not generally taken into consideration. In this narrative review, we consider the mechanistic and epidemiological evidence that food processing influences phytochemicals in selected food groups in the MD (olives, olive oil, vegetables and nuts), and that this influences the protective effects of these foods against chronic diseases associated with inflammation. We also examine how the pro-inflammatory properties of meat consumption can be modified by Mediterranean cuisine. We conclude by discussing whether food processing should be given greater consideration, both when recommending a MD to the consumer and when evaluating its health properties.

High gastrointestinal permeability and local metabolism of naringenin: influence of antibiotic treatment on absorption and metabolism

The present study aims to determine the permeability of naringenin in the stomach, small intestine and colon, to evaluate intestinal and hepatic first-pass metabolism, and to study the influence of the microbiota on the absorption and disposition of naringenin (3.5 μg/ml). A single-pass intestinal perfusion model in mice (n 4-6) was used. Perfusate (every 10 min), blood (at 60 min) and bile samples were taken and analysed to evaluate the presence of naringenin and its metabolites by an HPLC-MS/MS method. To study the influence of the microbiota on the bioavailability of naringenin, a group of animals received the antibiotic rifaximin (50 mg/kg per d) for 5 d, and naringenin permeability was determined in the colon. Naringenin was absorbed well throughout the gastrointestinal tract but mainly in the small intestine and colon (mean permeability coefficient 7.80 (SD 1.54) × 10(-4) cm/s and 5.49 (SD 1.86) × 10(-4) cm/s, respectively), at a level similar to the highly permeable compound, naproxen (6.39 (SD 1.23) × 10(-4) cm/s). According to the high amounts of metabolites found in the perfusate compared to the bile and plasma, naringenin underwent extensive intestinal first-pass metabolism, and the main metabolites excreted were sulfates (84.00 (SD 12.14)%), followed by glucuronides (8.40 (SD 5.67)%). Phase II metabolites were found in all perfusates from 5 min of sampling. Mice treated with rifaximin showed a decrease in naringenin permeability and in the amounts of 4-hydroxyhippuric acid and hippuric acid in the lumen. Naringenin was well absorbed throughout the gastrointestinal tract and its poor bioavailability was due mainly to high intestinal metabolism.

The tomato sauce making process affects the bioaccessibility and bioavailability of tomato phenolics: a pharmacokinetic study

Tomato sauce is the most commonly consumed processed tomato product worldwide, but very little is known about how the manufacturing process may affect the phenolic composition and bioavailability after consumption. In a prospective randomised, cross-over intervention study, we analysed the plasma and urinary levels of tomato phenolic compounds and their metabolites after acute consumption of raw tomatoes and tomato sauce, enriched or not with refined olive oil during production. Respectively, eleven and four phenolic metabolites were found in urine and plasma samples. The plasma concentration and urinary excretion of naringenin glucuronide were both significantly higher after the consumption of tomato sauce than raw tomatoes. The results suggest that the mechanical and thermal treatments during tomato sauce manufacture may help to deliver these potentially bioactive phenolics from the food matrix more effectively than the addition of an oil component, thus increasing their bioavailability.

Home Cooking and Phenolics: Effect of Thermal Treatment and Addition of Extra Virgin Olive Oil on the Phenolic Profile of Tomato Sauces

Tomato products are a key component of the Mediterranean diet, which is strongly related to a reduced risk of cardiovascular events. The effect of cooking time (15, 30, 45, and 60 min) and the addition of extra virgin olive oil (5 and 10%) on the phenolic content of tomato sauces was monitored using liquid chromatography coupled to tandem mass spectrometry. Concentration of phenolics in the tomato sauces decreased during the cooking process, with the exception of caffeic acid and tyrosol. The main degradation observed was the oxidation of quercetin, since the hydroxy-function at the C-ring of this flavonoid is not blocked by a sugar moiety, unlike rutin. Higher levels of virgin olive oil in tomato sauce seemed to enhance the extraction of phenolic compounds from the tomato, leading to higher phenolic contents in the sauces. Thus, the food matrix containing the phenolic compounds plays a crucial role in determining their accessibility.

Interaction of plant phenols with food macronutrients: characterisation and nutritional-physiological consequences

Polyphenols are dietary constituents of plants associated with health-promoting effects. In the human diet, polyphenols are generally consumed in foods along with macronutrients. Because the health benefits of polyphenols are critically determined by their bioavailability, the effect of interactions between plant phenols and food macronutrients is a very important topic. In the present review, we summarise current knowledge, with a special focus on the in vitro and in vivo effects of food macronutrients on the bioavailability and bioactivity of polyphenols. The mechanisms of interactions between polyphenols and food macronutrients are also discussed. The evidence collected in the present review suggests that when plant phenols are consumed along with food macronutrients, the bioavailability and bioactivity of polyphenols can be significantly affected. The protein-polyphenol complexes can significantly change the plasma kinetics profile but do not affect the absorption of polyphenols. Carbohydrates can enhance the absorption and extend the time needed to reach a maximal plasma concentration of polyphenols, and fats can enhance the absorption and change the absorption kinetics of polyphenols. Moreover, as highlighted in the present review, not only a nutrient alone but also certain synergisms between food macronutrients have a significant effect on the bioavailability and biological activity of polyphenols. The review emphasises the need for formulations that optimise the bioavailability and in vivo activities of polyphenols.

Gazpacho consumption is associated with lower blood pressure and reduced hypertension in a high cardiovascular risk cohort. Cross-sectional study of the PREDIMED trial

BACKGROUND AND AIM

Hypertension is a major public health problem and a leading cause of death and disability in both developed and developing countries, affecting one-quarter of the world's adult population. Our aim was to evaluate whether the consumption of gazpacho, a Mediterranean vegetable-based cold soup rich in phytochemicals, is associated with lower blood pressure (BP) and/or reduced prevalence of hypertension in individuals at high cardiovascular risk.

METHODS AND RESULTS

We selected 3995 individuals (58% women, mean age 67 y) at high cardiovascular risk (81% hypertensive) recruited into the PREDIMED study. BP, weight, and dietary and physical activity data were collected. In multivariate linear regression analyses, after adjustment, moderate and high gazpacho consumption categories were associated with reduced mean systolic BP of -1.9 mm Hg [95% confidence interval (CI): -3.4; -0.6] and -2.6 mm Hg (CI: -4.2; -1.0), respectively, and reduced diastolic BP of -1.5 mm Hg (CI: -2.3; -0.6) and -1.9 mm Hg (CI: -2.8; -1.1). By multiple-adjusted logistic regression analysis, gazpacho consumption was associated with a lower prevalence of hypertension, with OR = 0.85 (CI: 0.73; 0.99) for each 250 g/week increase and OR = 0.73 (CI: 0.55; 0.98) for high gazpacho consumption groups compared to the no-consumption group.

CONCLUSIONS

Gazpacho consumption was inversely associated with systolic and diastolic BP and prevalence of hypertension in a cross-sectional Mediterranean population at high cardiovascular risk. The association between gazpacho intake and reduction of BP is probably due to synergy among several bioactive compounds present in the vegetable ingredients used to make the recipe.

Setup of a UHPLC-QqQ-MS method for the analysis of phenolic compounds in cherry tomatoes, tomato sauce, and tomato juice

The setup of a novel, rapid, and sensitive UHPLC-QqQ-MS method was described for the determination of phenolic compounds in tomatoes and tomato-based products (tomato sauce and juice). Phenolic compounds including hydroxybenzoic and hydroxycinnamic acid derivatives, flavonols, and flavanones were detected, separated, and quantified in a 3 min chromatographic run. The main advantages of the method include high analyte recovery (90.1-115%), low limit of detection (0.008-0.167 mg L(-1)) and quantification (0.01-0.83 mg L(-1)), good accuracy (85.6-115%), and precision (<15%). The detection of the phenolic compounds varied according to the physicochemical nature of the extracts, but generally low matrix-dependent suppression/enhancement effects were observed in all three matrices. The possibility to transfer easily the existing HPLC to the fast UHPLC methods is very attractive, and with minor modifications, the methodology described may be applied to the phenolic characterization of a broad range of plant and food matrices.

Induction of peroxisome proliferator-activated receptor γ (PPARγ)-mediated gene expression by tomato (Solanum lycopersicum L.) extracts

Since beneficial effects related to tomato consumption partially overlap with those related to peroxisome proliferator-activated receptor γ (PPARγ) activation, our aim was to test extracts of tomato fruits and tomato components, including polyphenols and isoprenoids, for their capacity to activate PPARγ using the PPARγ2 CALUX reporter cell line. Thirty tomato compounds were tested; seven carotenoids and three polyphenols induced PPARγ2-mediated luciferase expression. Two extracts of tomato, one containing deglycosylated phenolic compounds and one containing isoprenoids, also induced PPARγ2-mediated expression at physiologically relevant concentrations. Furthermore, enzymatically hydrolyzed extracts of seven tomato varieties all induced PPARγ-mediated expression, with a 1.6-fold difference between the least potent and the most potent variety. The two most potent varieties had high flavonoid content, while the two least potent varieties had low flavonoid content. These data indicate that extracts of tomato are able to induce PPARγ-mediated gene expression in vitro and that some tomato varieties are more potent than others.

Validation of a new LC-MS/MS method for the detection and quantification of phenolic metabolites from tomato sauce in biological samples

Tomato is a good source of bioactive molecules such as vitamin C, carotenoids, and phenolic compounds. Up to now, only a few studies have evaluated the bioavailability of phenolic compounds from tomato. This paper presents the optimization of a method for the determination of phenolics in tomato and their metabolites in human urine and plasma after ingestion of tomato sauce. The sample preparation includes a SPE step to obtain cleaner extracts for injection in the LC-MS/MS system. The mean recovery of analytes ranged from 73 to 104% in plasma and from 65 to 106% in urine, the accuracy was between 90.3 and 115.0% in urine and between 85.7 and 115.0% in plasma, and the precision coefficient of variation was <15%. The method allowed detection and quantification limits of 0.5-29 and 2.0-90 ng mL⁻¹ in urine, respectively, and 0.5-30 and 2.0-105 ng mL⁻¹ in plasma, respectively, for the same phenolic compounds.