The Management of Irrigation and Potassium Fertilization to Mitigate the Effect of Light Frosts on the Phenolic and Volatile Compounds in Virgin Olive Oils.

The frequency of early frosts has increased in recent years, which are injurious to olive growing, causing losses in the yield and quality of virgin olive oil. In this research, it was studied how the management of agronomic factors mitigates frost damage in Arbequina olives, minimizing the loss of phenols and volatiles in virgin olive oil, at different fruit ripening stages. A Box-Behnken design and multivariate analysis were performed, with three levels of irrigation, potassium fertilization, and foliar copper application (15 treatments). Virgin olive oil was extracted from fresh and frozen olives. Light frost caused a significant decrease in the total phenols and secoiridoid compounds in and the antioxidant capacity of the frost-affected oils, which were perceived as more pungent and had the slight defect of "frostbitten olives". According to the Box-Behnken design, an 86% reference evapotranspiration (ET0) or higher with 100 potassium oxide units (UK2O) and a 100% ET0 or higher with 250 UK2O would be required to minimize the effect of light frost on phenols and volatiles. Partial Least Squares Regression-Discriminant Analysis (PLS-DA) differentiated the virgin olive oils according to their ripening stage and fresh and frost conditions. Moreover, PLS-DA positively correlated a 75-100% ET0 and 0 Uk2O with the dialdehydic form of the decarboxymethyl ligstroside aglycone (p-HPEA-EDA), the dialdehydic form of the decarboxymethyl oleuropein aglycone (3,4-DHPEA-EDA), the dialdehydic form of the ligstroside aglycone (p-HPEA-EDA-DLA), and with fruity, pungent, and bitter attributes. Precision agronomic management based on the needs of the crop itself would avoid unnecessary stress on olive trees and oil damage.

Effect of refining and pressing temperature on chemical attributes of canola oil produced in Chile

The consumption of vegetable oils is common in our daily diet. Rapeseed oil (canola oil) is the third most consumed edible oil in the world, followed by palm and soybean oils in terms of production. Rapeseed oil has a low proportion of saturated fatty acids, while it is rich in unsaturated fatty acids, as well as in healthy compounds such as phenols, tocopherols, phytosterols, carotenoids, and fat-soluble vitamins. However, processing technologies affect the content and functional activities of bioactive compounds in the oil. Aim: To assess any potential effect of hot or cold pressing and a refining process on the nutritional value and the profile of several bioactive compounds in canola oils produced in Chile. Methods: Canola oils were characterized regarding their fatty acid profile, phytosterol and tocopherol composition, total phenol content, and antioxidant activity, according to the mode of extraction (cold or hot pressed) and before and after bWeing subjected to a refining process. Results: Fatty acid profiles were not significantly different in any of the analyzed canola oils. Refining but not temperature extraction led to a sharp decrease of phytosterols and tocopherols. Hot pressing significantly increased the amount of total phenols (3.1 times) and the antioxidant activity measured by ORAC (3.1 times) and DPPH (8.3 times) compared to the cold extraction. However, phenolic concentration and antioxidant capacity decreased after refining. Conclusions: Refining processes should be adjusted to reduce the loss of bioactive compounds in the oil.

El consumo de aceites vegetales es habitual en nuestra dieta diaria. El aceite de colza (aceite de canola) es el tercer aceite comestible más consumido en el mundo, seguido por los aceites de palma y soja en términos de producción. El aceite de colza tiene una baja proporción de ácidos grasos saturados, mientras que es rico en ácidos grasos insaturados, así como en compuestos liposolubles saludables como fenoles, tocoferoles, fitoesteroles, carotenoides y vitaminas. Sin embargo, las tecnologías de procesamiento afectan el contenido y las actividades funcionales de los compuestos bioactivos en el aceite. Objetivo: Evaluar cualquier efecto potencial del prensado en caliente o en frío y un proceso de refinación sobre el valor nutricional y el perfil de varios compuestos bioactivos en los aceites de canola producidos en Chile. Métodos: Los aceites de canola se caracterizaron en cuanto a su perfil de ácidos grasos, composición de fitoesteroles y tocoferoles, contenido de fenoles totales y actividad antioxidante, según el modo de extracción (prensado en frío o en caliente) y antes y después de ser sometidos a un proceso de refinación. Resultados: Los perfiles de ácidos grasos no fueron significativamente diferentes en ninguno de los aceites de canola analizados. La refinación, pero no la extracción en caliente, condujo a una fuerte disminución de los fitoesteroles y tocoferoles. El prensado en caliente aumentó significativamente la cantidad de fenoles totales (3,1 veces) y la actividad antioxidante medida por ORAC (3,1 veces) y DPPH (8,3 veces) en comparación con la extracción en frío. Sin embargo, la concentración de fenoles y la capacidad antioxidante disminuyeron después del refinado. Conclusión: Los procesos de refinación deben ajustarse para reducir la pérdida de compuestos bioactivos en el aceite.

Effect of Structured Phenolic Lipids with EPA/DHA and Gallic Acid against Metabolic-Associated Fatty Liver Disease (MAFLD) in Mice.

Obesity is the leading risk factor for developing metabolic (dysfunction)-associated fatty liver disease (MAFLD). The food industry has an essential role in searching for new strategies to improve primary food sources to revert some of the metabolic alterations induced by obesity. There is consistent evidence that long-chain polyunsaturated fatty acids (n-3 LCPUFA) belonging to the n-3 series, i.e., eicosapentaenoic (20:5n-3, EPA) and docosahexaenoic (22:6n-3, DHA) acids, could revert some alterations associated with obesity-induced metabolic diseases. A relevant tool is the synthesis of structured acylglycerols (sAG), which include EPA or DHA at the sn-2 position. On the other hand, it has been reported that a crucial role of antioxidants is the reversion of MAFLD. In this work, we studied the effects of new molecules incorporating gallic acid (GA) into EPA/DHA-rich structured lipids. Mice were fed with a high-fat diet (60%) for three months and were then divided into five groups for supplementation with sAG and sAG structured with gallic acid (structured phenolic acylglycerols, sPAG). sPAG synthesis was optimized using a 2²-screening factorial design based on the response surface methodology (RSM). Our results show that treatment of sPAG was effective in decreasing visceral fat, fasting glycemia, fasting insulin, suggesting that this new molecule has a potential use in the reversal of MAFLD-associated alterations.

The Impact of Mild Frost Occurring at Different Harvesting Times on the Volatile and Phenolic Composition of Virgin Olive Oil.

The organoleptic characteristics of virgin olive oil (VOO), together with its nutritional and health properties, have led the olive tree to be cultivated beyond the Mediterranean basin, reaching latitudes with colder climates, with minimum temperatures below 0 °C and with a higher probability of early frosts. The freezing of olives generates destruction within the tissues and promotes degradation reactions. In this study, the impact of mild frost occurring at different harvesting times on the composition of volatiles and phenolic compounds in VOO were investigated. Arbequina variety olives were harvested at different stages of ripening. Half of the olives were subjected to oil extraction and the other half were frozen at -3 ± 1 °C for 12 h prior to oil extraction. A significant decrease of phenolic compounds with harvesting time was observed in both types of oils (fresh and frozen olives). Oils from frozen olives presented a slightly higher content of total phenols, except in the advanced ripening stage (September), and a slightly lower content of volatile compounds at all harvesting times. In addition, a higher content of 3,4-DHPEA-EDA was observed in oils from frozen olives, which is attributed to an early action of the endogenous ß-glucosidase enzyme on oleuropein in freeze-damaged olive fruits. Principal component analysis and Discriminant Partial Least Square Regression allowed the oils to be classified according to the type of fruit (fresh and frozen) and the month of harvest. This study would indicate that mild frost would have a low impact on the chemical composition of virgin olive oil, although, this depends on the ripening stage.

Effect of Storage Conditions on the Quality of Arbequina Extra Virgin Olive Oil and the Impact on the Composition of Flavor-Related Compounds (Phenols and Volatiles).

Commercialization of extra virgin olive oil (EVOO) requires a best before date recommended at up to 24 months after bottling, stored under specific conditions. Thus, it is expected that the product retains its chemical properties and preserves its 'extra virgin' category. However, inadequate storage conditions could alter the properties of EVOO. In this study, Arbequina EVOO was exposed to five storage conditions for up to one year to study the effects on the quality of the oil and the compounds responsible for flavor. Every 15 or 30 days, samples from each storage condition were analyzed, determining physicochemical parameters, the profiles of phenols, volatile compounds, α-tocopherol, and antioxidant capacity. Principal component analysis was utilized to better elucidate the relationships between the composition of EVOOs and the storage conditions. EVOOs stored at -23 and 23 °C in darkness and 23 °C with light, differed from the oils stored at 30 and 40 °C in darkness. The former was associated with a higher quantity of non-oxidized phenolic compounds and the latter with higher elenolic acid, oxidized oleuropein, and ligstroside derivatives, which also increased with storage time. (E)-2-nonenal (detected at trace levels in fresh oil) was selected as a marker of the degradation of Arbequina EVOO quality over time, with significant linear regressions identified for the storage conditions at 30 and 40 °C. Therefore, early oxidation in EVOO could be monitored by measuring (E)-2-nonenal levels.

Thermal Behavior Improvement of Fortified Commercial Avocado (Persea americana Mill.) Oil with Maqui (Aristotelia chilensis) Leaf Extracts.

Avocado oil is considered a highly prized food due to its nutritional contribution. On the other hand, Aristotelia chilensis (Molina) Stuntz (Elaeocarpaceae), common name "maqui", is an endemic fruit in Chile, well known for its exceptional antioxidant properties. In general, maqui by-products such as leaves are considered as waste. Thus, maqui leaves extracts were used to improve the stability of vegetable oils, particularly avocado oil. Hence, avocado oil was fortified with two extracts (ethyl ether and methanol) obtained of maqui leaves and exposed to 120 °C for 386 h in an oven. The results showed a high content of monounsaturated fatty acids (69.46%, mainly oleic acid), followed by polyunsaturated fatty acids (16.41%, mainly linoleic acid) and finally saturated fatty acids (14.13%). The concentration of the total phenolic compounds in the pure oil, ethyl ether and methanol maqui leaves extracts were 45.8, 83.7, and 4100.9 ppm, respectively. In addition, the antioxidant activity was 5091.6 and 19,452.5 µmol Trolox eq/g for the ethyl ether and methanol extracts, respectively. The secondary degradation compounds showed significant differences between the fortified and non-fortified samples after 144 h and the TG/DTG analysis showed a significant increment of 7 °C in the degradation temperature (Tonset) of avocado oil fortified with the methanol extract when compared to the non-fortified oil and fortified oil with ethyl ether extract. After heating for 336 h, fortified oil with methanol extract reached the limit percentages of polar compounds, while pure oil reached it in a shorter time, i.e., 240 h. Based on the results, avocado oil can be protected with natural additives such as extracts obtained from maqui leaves, leading to an increase in its thermo-oxidative stability.

EPA/DHA Concentrate by Urea Complexation Decreases Hyperinsulinemia and Increases Plin5 in the Liver of Mice Fed a High-Fat Diet.

Dietary intake of eicosapentaenoic/docosahexaenoic acid (EPA/DHA) reduces insulin resistance and hepatic manifestations through the regulation of metabolism in the liver. Obese mice present insulin resistance and lipid accumulation in intracellular lipid droplets (LDs). LD-associated proteins perilipin (Plin) have an essential role in both adipogenesis and lipolysis; Plin5 regulates lipolysis and thus contributes to fat oxidation. The purpose of this study was to compare the effects of deodorized refined salmon oil (DSO) and its polyunsaturated fatty acids concentrate (CPUFA) containing EPA and DHA, obtained by complexing with urea, on obesity-induced metabolic alteration. CPUFA maximum content was determined using the Box-Behnken experimental design based on Surface Response Methodology. The optimized CPUFA was administered to high-fat diet (HFD)-fed mice (200 mg/kg/day of EPA + DHA) for 8 weeks. No significant differences (p > 0.05) in cholesterol, glycemia, LDs or transaminase content were found. Fasting insulin and hepatic Plin5 protein level increased in the group supplemented with the EPA + DHA optimized product (38.35 g/100 g total fatty acids) compared to obese mice without fish oil supplementation. The results suggest that processing salmon oil by urea concentration can generate an EPA+DHA dose useful to prevent the increase of fasting insulin and the decrease of Plin5 in the liver of insulin-resistant mice.

Iron-induced derangement in hepatic Δ-5 and Δ-6 desaturation capacity and fatty acid profile leading to steatosis: Impact on extrahepatic tissues and prevention by antioxidant-rich extra virgin olive oil.

The administration of iron induces liver oxidative stress and depletion of long-chain polyunsaturated fatty acids (LCPUFAs), n-6/n-3 LCPUFA ratio enhancement and fat accumulation, which may be prevented by antioxidant-rich extra virgin olive oil (AR-EVOO) supplementation. Male Wistar rats were subjected to a control diet (50 mg iron/kg diet) or iron-rich diet (IRD; 200 mg/kg diet) with alternate AR-EVOO for 21 days. Liver fatty acid (FA) analysis was performed by gas-liquid chromatography (GLC) after lipid extraction and fractionation, besides Δ-5 desaturase (Δ-5 D) and Δ6-D mRNA expression (qPCR) and activity (GLC) measurements. The IRD significantly (p < 0.05) increased hepatic total fat, triacylglycerols, free FA contents and serum transaminases levels, with diminution in those of n-6 and n-3 LCPUFAs, higher n-6/n-3 ratios, lower unsaturation index and Δ5-D and Δ6-D activities, whereas the mRNA expression of both desaturases was enhanced over control values, changes that were prevented by concomitant AR-EVOO supplementation. N-6 and n-3 LCPUFAs were also decreased by IRD in extrahepatic tissues and normalized by AR-EVOO. In conclusion, AR-EVOO supplementation prevents IRD-induced changes in parameters related to liver FA metabolism and steatosis, an effect that may have a significant impact in the treatment of iron-related pathologies or metabolic disorders such as non-alcoholic fatty liver disease.

Anti-oxidative and anti-inflammatory effects of Rosa Mosqueta oil supplementation in rat liver ischemia-reperfusion.

Ischemia-reperfusion (IR) is a deleterious condition associated with liver transplantation or resection that involves pro-oxidant and pro-inflammatory mechanisms. Considering that Rosa Mosqueta (RM) oil composition is rich in protective components such as α-linolenic acid (ALA) and tocopherols, we studied the effects of RM oil supplementation given prior to an IR protocol. Male Sprague-Dawley rats receiving RM oil (0.4 mL d-1) for 21 days were subjected to 1 h of ischemia followed by 20 h reperfusion. Parameters of liver injury (serum transaminases, histology), oxidative stress [liver contents of protein carbonyls, thiobarbituric acid reactants, Nrf2 activity and its target mRNA expression of heme oxygenase-1 (HO-1) and NADPH-quinone oxidoreductase-1 (NQO-1)] and inflammation [nuclear factor-κB (NF-κB) and its target mRNA expression of tumor necrosis factor-α (TNF-α) and interleukine-1ß (IL-1ß)] were studied. RM oil increased liver ALA and its derived EPA and DHA fatty acids' contents, with enhancement in those of α- and γ-tocopherols. IR induced inflammatory liver injury, with enhancement in serum transaminases, oxidative stress-related parameters with reduced Nrf2 signaling, and higher pro-inflammatory cytokines, indexes that were attenuated or abrogated by RM oil pretreatment. It is concluded that RM oil supplementation represents a novel non-invasive preconditioning strategy against liver injury induced by IR that has potential clinical applications in metabolic stress conditions.

Molecular mechanisms related to the hepatoprotective effects of antioxidant-rich extra virgin olive oil supplementation in rats subjected to short-term iron administration.

Enhanced iron levels in liver are associated with oxidative stress development and damage with increased fat accumulation. The aim of this work was to assess the hypothesis that antioxidant-rich extra virgin olive oil (AR-EVOO) counteracts iron-rich diet (IRD)-induced oxidative stress hindering hepatic steatosis. Male Wistar rats were fed and IRD (200 mg iron/kg diet) versus a control diet (CD; 50 mg iron/kg diet) with alternate AR-EVOO supplementation (100 mg/day) for 21 days. IRD induced liver steatosis and oxidative stress (higher levels of protein oxidation and lipid peroxidation with glutathione depletion), mitochondrial dysfunction (decreased citrate synthase and complex I and II activities) and loss of polyunsaturated fatty acids (PUFAs), with a drastic enhancement in the sterol regulatory element-binding protein-1c (SREBP-1c)/peroxisome proliferator-activated receptor-α (PPAR-α) ratio upregulating the expression of lipogenic enzymes (acetyl-CoA carboxylase, fatty acid (FA) synthase and stearoyl desaturase 2) and downregulating those involved in FA oxidation (carnitine palmitoyl transferase and acyl-CoA oxidase) over values in the CD group. IRD also upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) and its target genes. AR-EVOO supplementation alone did not modify the studied parameters, however, IRD combined with AR-EVOO administration returned IRD-induced changes to baseline levels of the CD group. It is concluded that IRD-induced non-alcoholic fatty liver disease (NAFLD) is prevented by AR-EVOO supplementation, which might be related to the protective effects of its components such as hydroxytyrosol, oleic acid, tocopherols and/or PUFAs, thus representing a suitable anti-steatotic strategy to avoid progression into more severe stages of the disease, underlying NAFLD associated with iron overloading pathologies or obesity.

Role of dietary α- and γ-tocopherol from Rosa mosqueta oil in the prevention of alterations induced by high-fat diet in a murine model.

OBJECTIVE: The aim of this study was to evaluate the contribution of tocopherols present in Rosa mosqueta oil (RM) in the prevention of high-fat diet (HFD)-induced alterations. METHODS: Male C57 BL/6 J mice (n = 9/group) were fed for 12 wk and divided into four groups: control (CD; 10% kcal fat, 20% kcal protein, 70% kcal carbohydrates); HFD (60% as fat, 20% kcal protein, 20% kcal carbohydrates); HFD + RM (0.01 mL/g body weight/d); and HFD + RM- without tocopherols (0.01 mL/g body weight/d). Parameters of obesity, liver steatosis (histology, triacylglycerols content), inflammation (adipose NLRP3 inflammasome, tumor necrosis factor-α and interleukin-1 ß expression, hepatic nuclear factor-κB) and oxidative stress (hepatic Nrf2 activation, carbonylated proteins) were evaluated. RESULTS: Liver steatosis, inflammatory, and oxidative stress parameters were significantly (P < 0.05) increased in the HFD + RM- compared with the HFD + RM, with no differences between HFD and HFD + RM-. CONCLUSION: The present study suggests that α- and γ-tocopherols from RM may have an important role in the prevention of alterations induced by HFD.

Effect of the composition of extra virgin olive oils on the differentiation and antioxidant capacities of twelve monovarietals.

The effect of the composition of twelve varieties of extra virgin olive oils (EVOOs) on their differentiation based in agronomic criteria and on the antioxidant capacity was studied. Principal component analysis permitted an overview of the samples and their compositions, showing evidence of grouping and correlation between antioxidant capacity, oleuropein and ligstroside derivatives (OLD) and specific extinction at 270. Oleic and linoleic acids, 3,4-DHPEA-EA and p-HPEA-EDA (OLD), unsaturated/saturated ratio and induction time (IT) allowed the correct classification of samples according to year of harvest, ripening stage and variety. The antioxidant capacity of EVOOs was satisfactory predicted through a partial least square model based on ΔK, hydroxytyrosol, pinoresinol, oleuropein derivate and IT. Validation of the model gave a correlation R>0.83 and an error of 7% for independent samples. This model could be a useful tool for the olive industry to highlight the nutritional quality of EVOOs and improve their marketing.

Supplementation with Docosahexaenoic Acid and Extra Virgin Olive Oil Prevents Liver Steatosis Induced by a High-Fat Diet in Mice through PPAR-α and Nrf2 Upregulation with Concomitant SREBP-1c and NF-kB Downregulation.

SCOPE: Nonalcoholic fatty liver disease is the most common cause of liver disease, for which there is no validated drug therapy at present time. In this respect, the PUFA docosahexaenoic acid (DHA; C22:6 n-3) modulate lipid metabolism in the liver, and extra virgin olive oil (EVOO) has hepatoprotective effects. METHODS AND RESULTS: The effect of combined DHA (C22:6 n-3) and EVOO administration to mice on oxidative stress and metabolic disturbances induced by high-fat diet (HFD) is evaluated. Male C57BL/6J mice are fed with a control diet (10% fat, 20% protein, and 70% carbohydrates) or an HFD (60% fat, 20% protein, and 20% carbohydrates) for 12 weeks. Animals are supplemented with DHA (50 mg/kg/day), EVOO (50 mg/kg/day), or DHA + EVOO through oral route. DHA + EVOO cosupplementation results in greater protection (p < 0.05) over that elicited by DHA or EVOO supply alone, when compared to the damage induced by HFD. DHA + EVOO significantly reduces hepatic steatosis, oxidative stress, systemic inflammation, and insulin resistance. CONCLUSION: Synergistic beneficial effects of DHA + EVOO supplementation are associated with the activation/inactivation of key transcription factors involved in the above-mentioned processes. Data presented indicate that dietary supplementation with DHA + EVOO drastically reduces the development of nonalcoholic fatty liver disease.

Supplementation with antioxidant-rich extra virgin olive oil prevents hepatic oxidative stress and reduction of desaturation capacity in mice fed a high-fat diet: Effects on fatty acid composition in liver and extrahepatic tissues.

OBJECTIVE: The aim of this study was to assess the effect of dietary supplementation with extra virgin olive oil (EVOO) in mice on the reduction of desaturase and antioxidant enzymatic activities in liver, concomitantly with long-chain polyunsaturated fatty acids (LCPUFA) profiles in liver and extrahepatic tissues induced by a high-fat diet (HFD). METHODS: Male mice C57 BL/6 J were fed with a control diet (CD; 10% fat, 20% protein, 70% carbohydrates) or an HFD (60% fat, 20% protein, 20% carbohydrates) for 12 wk. Animals were supplemented with 100 mg/d EVOO with different antioxidant contents (EVOO I, II, and III). RESULTS: After the intervention, blood and several tissues were analyzed. Dietary supplementation with EVOO with the highest antioxidant content and antioxidant capacity (EVOO III) significantly reduced fat accumulation in liver and the plasmatic metabolic alterations caused by HFD and produced a normalization of oxidative stress-related parameters, desaturase activities, and LCPUFA content in tissues. CONCLUSIONS: Data suggest that dietary supplementation with EVOO III may prevent oxidative stress and reduction of biosynthesis and accretion of ω-3 LCPUFA in the liver of HFD-fed mice.

Anti-steatotic effects of an n-3 LCPUFA and extra virgin olive oil mixture in the liver of mice subjected to high-fat diet.

Non-alcoholic fatty liver disease (NAFLD) is characterized by liver steatosis, oxidative stress, and drastic depletion of n-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA), namely, eicosapentaenoic acid (C20:5 n-3, EPA) and docosahexaenoic acid (C22:6 n-3, DHA), which trigger lipolysis stimulation and lipogenesis inhibition. Extra virgin olive oil (EVOO) has important antioxidant effects. This study evaluated the anti-steatotic effects of n-3 LCPUFA plus EVOO in the liver of male C57BL/6J mice subjected to a control diet (CD) (10% fat, 20% protein, 70% carbohydrate) or high fat diet (HFD) (60% fat, 20% protein, 20% carbohydrate), without and with supplementation with n-3 LCPUFA (100 mg per kg per day) plus EVOO (100 mg per kg per day) for 12 weeks. HFD induced (i) liver steatosis (increased total fat, triacylglycerols, and free fatty acid total contents), (ii) higher fasting serum glucose and insulin levels and HOMA index, total cholesterol, triacylglycerols and TNF-α and IL-6, (iii) liver and plasma oxidative stress enhancement, (iv) depletion of the n-3 LCPUFA hepatic content, and (v) increment in lipogenic enzyme activity and reduction in lipolytic enzyme activity. These changes were either reduced (p < 0.05) or normalized to control the values in animals subjected to HFD supplemented with n-3 LCPUFA plus EVOO. In conclusion, n-3 LCPUFA plus EVOO intervention exerts anti-steatotic effects underlying antioxidant and anti-inflammatory responses, improved insulin sensitivity, and recovery of the lipolytic/lipogenic status of the liver altered by HFD, and supports the potential therapeutic use of n-3 LCPUFA plus EVOO supplementation in the treatment of human liver steatosis induced by nutritional factors or other etiologies.

Influence of agroclimatic parameters on phenolic and volatile compounds of Chilean virgin olive oils and characterization based on geographical origin, cultivar and ripening stage.

BACKGROUND: This study involved two commercial orchards located in Limarí Valley and Molina from two important Chilean production zones of extra virgin olive oil (EVOO). The investigation evaluated the effects of climate, soil composition, agricultural practices (fertilization and irrigation) and variety (considering two harvests) on the compounds responsible for the flavor of EVOO (volatiles and phenols) and how these compounds can explain the differences in chemical profiles by geographical origin, cultivar and fruit ripeness stage. RESULTS: Varieties from the Limarí Valley presented the highest content of phenolic compounds. A significant relationship (P < 0.05) between volatile compounds and climate indicated that the compounds produced via the lipoxygenase cascade were affected by the maximum temperature and, to a lesser extent, by evapo-transpiration and irrigation. The selection of different individual phenolic and volatile compounds independently allowed the significant differentiation of EVOOs, principally by geographical origin, crop season, fruit ripeness stage and, in a few cases, by cultivar. CONCLUSION: Soil and climate of the Chilean regions have much more influence than cultivars on the concentration of sensory quality compounds. Difference in latitude between orchards increases the importance of the geographical origin on the virgin olive oil chemical composition while full irrigation decreases the impact of the cultivar.

Comparative study of virgin olive oil quality from single varieties cultivated in Chile and Spain.

Olive tree varieties that were cultivated only in the Mediterranean basin a few decades ago are now planted in the Southern Hemisphere as well. The chemical composition of the oils produced in countries as far distant as Spain and Chile are affected by differences in latitude and climate. In this work, seven monovarietal virgin olive oils from Chile (Arbequina, Barnea, Frantoio, Koroneiki, Leccino, Manzanilla and Picual) have been characterized by the chemical compounds responsible for taste (phenols) and aroma (volatiles). The oils were produced in five regions of Chile, and the concentration values of some chemical compounds were related to the geographical location of the olive tree orchards. Virgin olive oils from the major cultivars, Arbequina and Picual, were characterized in comparison with the same monovarietal oils produced in Spain. The concentration values of fourteen volatile compounds showed significant differences (p < 0.05) between the oils produced in Spain and Chile. Concerning the phenol composition, main differences were found on the secoiridoids derivatives of oleuropein and ligstroside, apigenin and luteolin.

Study of some physicochemical and functional properties of quinoa (chenopodium quinoa willd) protein isolates.

The amino acid composition and the physicochemical and functional properties of quinoa protein isolates were evaluated. Protein isolates were prepared from quinoa seed by alkaline solubilization (at pH 9, called Q9, and at pH 11, called Q11) followed by isoelectric precipitation and spray drying. Q9 and Q11 had high levels of essential amino acids, with high levels of lysine. Both isolates showed similar patterns in native/SDS-PAGE and SEM. The pH effect on fluorescence measurements showed decreasing fluorescence intensity and a shift in the maximum of emission of both isolates. Q9 showed an endotherm with a denaturation temperature of 98.1 degrees C and a denaturation enthalpy of 12.7 J/g, while Q11 showed no endotherm. The protein solubility of Q11 was lower than that of Q9 at pH above 5.0 but similar at the pH range 3.0-4.0. The water holding capacity (WHC) was similar in both isolates and was not affected by pH. The water imbibing capacity (WIC) was double for Q11 (3.5 mL of water/g isolate). Analysis of DSC, fluorescence, and solubility data suggests that there is apparently denaturation due to pH. Some differences were found that could be attributed to the extreme pH treatments in protein isolates and the nature of quinoa proteins. Q9 and Q11 can be used as a valuable source of nutrition for infants and children. Q9 may be used as an ingredient in nutritive beverages, and Q11 may be used as an ingredient in sauces, sausages, and soups.

Composición en acidos grasos y proximal de siete especies de pescado de Isla de Pascua / Fatty acid composition and proximate of seven fish species of Eastern Island

En el último tiempo se ha puesto un gran énfasis en el estudio de la presencia de ácidos grasos poliinsaturados de la familia omega-3 en alimentos de origen marino, debido a sus efectos beneficiosos descritos en relación con las enfermedades cardiovasculares, las cuales son la principal causa de muerte en países occidentales. Para obtener una mayor información, acerca de la composición de la materia grasa presente en las principales especies marinas consumidas habitualmente por la población de Isla de Pascua, se analizó siete especies de pescados: Maito (Acanthurus leucopareius), Matuko (Bodianus vulpinus), Marau (Myripristis tiki), Nanue (Kiphosus bigibus), Moki (Mori y Marari, Anampses caeruleopunctatus), Puia (Girellops nebulosus) y Raea (Cheilodactilus plessisi). Se determinó el perfil en ácidos grasos por cromatografía Gas-líquido y la composición proximal para cada especie. De acuerdo al contenido graso: Nanue y Marari presentaron el mayor porcentaje en lípidos, con valores de 2,8 y 3,6 por ciento respectivamente. El perfil en ácidos grasos, expresado como porcentaje de ésteres metílicos, mostró que el grupo más importante fue el de los ácidos grasos saturados (SFA, 35.1-54 por ciento) seguido por los ácidos grasos poliinsaturados (PUFA, 22-42,5 por ciento). El ácido palmítico fue el principal componente entre los ácidos grasos saturados, mientras que el ácido oleico fue el principal entre los monoinsaturados. Entre los ácidos grasos de la familia omega-3 se destacaron el ácido eicosapentaenoico (EPA, C20:5w3) y ácido docosahexaenoico (DHA, C22:6w3) con un rango entre 2.0-12 por ciento) y 1.8-18.3 por ciento respectivamente. De la familia omega-6 se destacó el ácido araquidónico (AA, C20:4w6) con un rango entre 1.9-10 por ciento. Considerando la composición en ácidos grasos y el contenido lipídico, marari fue la especie con el mayor aporte de ácidos grasos w-3 y w-6, con valores de 850 t 240 mg por cien gramos de parte cosmetible respectivamente

Composición en ácidos grasos y aporte de colesterol de conservas de jurel, sardina, salmón y atún al natural / Composition in fatty acid and contribution of cholesterol of jurel, sardine, salmon and tuna in natural fish canned

Para obtener más información acerca de la composición de la materia grasa presente en conservas de pescado de consumo habitual en Chile, se analizaron 4 tipos de conservas al natural, jurel, salmón, sardina y atún. Se determinaron sus pérfiles en ácidos grasos y el contenido de colesterol de cromatografía gas-líquido. Se encontro que las materias grasas contenidas en las conservas era preferentemente poliinsaturada, con predominio de ácidos grasos de la familia omega-3 entre los que se destacaron el ácido eicosapentaenoico (EPA) y ácido docodahexaenoico (DHA) con un rango entre 5 por ciento-11 por ciento y 12 por ciento-22 por ciento respectivamente. De la familia omega-6 se destacó el ácido araquidónico (AA) con un rango entre el 2 por ciento-4 por ciento. El contenido de colesterol en las conservas de pescado fue similar al presentado por otras carnes de origen animal con valores que flutuaron entre 41 mg y 86 mg de colesterol por 100 gramos de parte comestible. La conserva de atún fue la que presentó menor aporte de este nutriente. Los aporte de EPA, DHA y ácidos grasos de la familia omega-3 presentaron rango entre 95-604; 390-1163 y 609-2725 mg por 100 gramos de parte comestible respectivamente. Debido a estos resultados es importante enfatizar el consumo de este tipo de conservas de pescado al natural ya que representan principalmente una buena fuente dietaria de ácidos grasos poliinsaturados de la familia omega-3. Las recomendaciones internacionales indican aumentar el consumo de pescado debido al los efectos beneficiosos descritos en relación a enfermedades cardiovasculares, las cuales son la principal causa de muerte en Chile, país con una amplia variedad de alimentos de origen marino, pero con una respuesta contradictoria sobre el consumo el cual no ha sido incorporado en la dieta habitual