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1.
Molecules ; 28(10)2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37241988

RESUMEN

The aim of the study was to determine the stability and heat resistance of extra premium olive oil. The study material consisted of six extra virgin olive oils (EVOO) obtained from Spain. Four samples were single-strain olive oils: Arbequina, Picual, Manzanilla, and Cornicabra. Two samples were a coupage of Arbequina and Picual varieties: Armonia (70% Arbequina and 30% Picual) and Sensation (70% Picual and 30% Arbequina). Olive oil samples were heated at 170 °C and 200 °C in a pan (thin layer model). In all samples, changes in indexes of lipid nutritional quality (PUFA/SFA, index of atherogenicity, index of thrombogenicity, and hypocholesterolemic/hypercholesterolemic ratio), changes in tocopherol, total polar compounds content, and triacylglycerol polymers were determined. Heating olive oil in a thin layer led to its degradation and depended on the temperature and the type of olive oil. Increasing the temperature from 170 to 200 °C resulted in significantly higher degradation of olive oil. At 200 °C, deterioration of lipid nutritional indices, total tocopherol degradation, and formation of triacylglycerol polymers were observed. A twofold increase in the polar fraction was also observed compared to samples heated at 170 °C. The most stable olive oils were Cornicabra and Picual.


Asunto(s)
Olea , Tocoferoles , Aceite de Oliva , Aceites de Plantas , Triglicéridos , Temperatura , Polimerizacion , Calefacción , Evaluación Nutricional , Fenoles/análisis , Polímeros
2.
Food Res Int ; 164: 112386, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36737971

RESUMEN

The tocopherol (T) and tocotrienol (T3) profile were investigated in the present study for four hundred and eighteen plant oil samples, including thirty-one families, eighty-two species, and five cross-species. Fifteen species were dominated by tocotrienols, while sixty-seven - by tocopherols. The mean proportion of γ-T was almost half of the total tocochromanol content (49.3%) in the investigated samples, while α-T constituted to one quarter (25.0%), and the remaining other tocochromanols were present as minor constituents. A strong relationship between the taxonomic plant origin and the presence of the characteristic tocochromanol profile in oils obtained from those plants was noted. This is the first study to demonstrate that not only monocotyledonous, but also dicotyledons families can be rich in tocotrienols. The usefulness of statistical tools - principal component analysis (PCA) and hierarchical cluster analysis (HCA) for plant sample discrimination based on their tocochromanol profile was also shown.


Asunto(s)
Tocoferoles , Tocotrienoles , Humanos , Tocoferoles/análisis , Tocotrienoles/análisis , Aceites de Plantas , Análisis de Componente Principal , Análisis por Conglomerados
3.
Anal Bioanal Chem ; 415(13): 2523-2534, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36567330

RESUMEN

The aim of this study was to track changes in the volatilome of cold-pressed oil and press cakes obtained from roasted seeds and to combine it with the profile of non-volatile metabolites in a single study, in order to understand pathways of volatile organic compound (VOC) formation caused by thermal processing. Comprehensive two-dimensional gas chromatography-time of flight mass spectrometry was used for the analysis of VOCs in cold-pressed oils and corresponding press cakes obtained after roasting of seeds at 140 and 180 °C prior to pressing. Contents of primary metabolites (amino acids, saccharides, fatty acids) as well as selected secondary metabolites (glucosinolates, polyphenols) were determined, as many of them serve as precursors to volatile compounds formed especially in thermal reactions. After roasting, the formation of Maillard reaction products increased, which corresponded to the reduction of free amino acids and monosaccharides. Moreover, levels of the products of thermal oxidation of fatty acids, such as aldehydes and ketones, increased with the increasing temperature of roasting, although no significant changes were noted for fatty acids. Among sulphur-containing compounds, contents of the products and intermediates of methionine Strecker degradation increased significantly with the increasing temperature of roasting. Degradation of glucosinolates to nitriles occurred after thermal treatment. The results of this study confirmed that seed roasting before cold pressing has a significant effect on the volatiles, but also indicated roasting-induced changes in non-volatile metabolites of oil and press cake. Such an approach helps to understand metabolic changes occurring during rapeseed processing in cold-pressed oil production.


Asunto(s)
Glucosinolatos , Semillas , Ácidos Grasos/análisis , Cromatografía de Gases y Espectrometría de Masas , Glucosinolatos/análisis , Aceites de Plantas/química , Aceite de Brassica napus , Semillas/química , Frío
4.
Molecules ; 27(23)2022 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-36500618

RESUMEN

The purpose of this study was to explore the effects of roasting linseeds on the pigment, lipid profile, bioactive components, and oxidative stability of the extracted oils. The linseed varieties Giza 11, Giza 12, Sakha 3, and Sakha 6 were roasted at 180 °C for 10 min, and the oils were extracted by cold pressing. The results showed that, after roasting, there was an increase in oil percentage and peroxide value, as well as small increases in p-anisidine and acid values. Roasting also caused an increase in chlorophyll content, while lutein and ß-carotene tend to slightly decrease, except in the Giza 11 variety. The total phenolics content was markedly enhanced after roasting. Omega-3 fatty acids were not affected by the roasting process. The total amounts of tocochromanol were found to decrease in the Giza 12 and Sakha 6 varieties after roasting. Plastochromanol-8 increased in all varieties after roasting. The phytosterol composition was minimally affected by roasting. Roasting enhanced the stability of the extracted oils, increasing the induction period and decreasing EC50 values. These results may thus help to discriminate between the different linseed varieties and serve to recommend the use of roasting to enhance the oxidative stability of extracted oil.


Asunto(s)
Ácidos Grasos Omega-3 , Lino , Fitosteroles , Aceites de Plantas , Semillas , Aceite de Linaza , Ácidos Grasos
5.
Molecules ; 27(8)2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35458659

RESUMEN

Polar compounds and polymers are regarded as the most reliable indicators of oil degradation during heating, and it is desirable to find methods to reduce these undesirable changes. The aim of this study was (1) to determine the effect of enrichment with black cumin cold-pressed oil (CP) or essential oil obtained from black cumin cold-pressed oil in an equivalent amount (ES) on limiting the polar compounds and polymers content in blends based on refined rapeseed oil during high-temperature heating in a thin layer; (2) to determine tocochromanol losses and their effect on the change content of the polar compounds and polymers. Four fortified oils were made from refined rapeseed oil and one of the four additives (10% CP, 20% CP, 0.1% ES, and 0.2% ES). All fortified oils and refined rapeseed oil as a control sample were heated at 170 and 200 °C on the pan in a thin layer and evaluated regarding loss of individual tocochromanol homologs by HPLC-FL, polar compounds content, oxidized triacylglycerols (TAG), and polymers content by HPSEC-ELSD. Additionally, the fatty acid profile in nonheated oil was investigated. Tocochromanol analysis showed loss in all the samples. At 170 °C polymers were not detected; no difference was noted for polar compounds and oxidized TAG content; only the 20% CP sample showed a higher level. At 200 °C the 10% CP sample exhibited a significant protective effect with the lowest content of polar compounds, oxidized TAG, and dimers.


Asunto(s)
Nigella sativa , Frío , Calefacción , Aceites de Plantas , Polímeros , Aceite de Brassica napus
6.
J Oleo Sci ; 71(1): 43-50, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35013038

RESUMEN

The aim of this study was to examine olive oils purchased in Poland for their compliance with label declarations and EEC criteria. Statistical analysis was used to compare the olive oils in terms of their content and composition of essential constituents and color parameters. Fifty olive oils (extra virgin, bioextra virgin, cold-pressed, refined, and pomace) from different countries (Spain, Italy, Greece, Portugal, Germany, France, Israel, and the European Union), were purchased commercially in Poland. The contents of triacylglycerols, sterols, and tocopherols, the fatty acid composition, and the color parameters were determined using chromatographic and spectrophotometric methods. Statistical methods were used to divide the olive oils into clusters. Our results show that the composition and color parameters of olive oils available commercially in Poland, excluding pomace olive oils, are similar. It can thus be concluded that, irrespective of the type of olive oil stated on the label, their quality is the same or very similar.


Asunto(s)
Color , Ácidos Grasos/análisis , Análisis de los Alimentos/métodos , Etiquetado de Alimentos , Calidad de los Alimentos , Aceite de Oliva/análisis , Aceite de Oliva/química , Fitosteroles/análisis , Tocoferoles/análisis , Triglicéridos/análisis , Polonia
7.
Nat Prod Res ; 36(1): 474-478, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32586126

RESUMEN

The seeds and oil yield and profile/levels of fatty acids, tocopherols and phytosterols in seed oils of twelve Japanese quince (Chaenomeles japonica) genotypes were studied. The seeds and oil yield ranged from 3.8 to 5.7% w/w fresh fruit, and 10.9 to 14.6% w/w dry weight seeds, respectively. The range of three predominated fatty acids C16:0, C18:1 and C18:2 in the seed oil of twelve Japanese quince genotypes were 8.1-9.8, 37.5-48.1, and 40.1-50.3%, respectively. α-Tocopherol and ß-sitosterol were the main minor lipophilic compounds detected in all investigated genotypes. The percentage of predomination of α-tocopherol and ß-sitosterol in each investigated genotype was very similar and amounted to 97-99% of total tocopherols and 76-80% of total phytosterols, respectively. The range of total content tocopherols and phytosterols in 12 genotypes of Japanese quince were 91.9-129.3 and 7830-14166 mg/100 g oil, respectively.


Asunto(s)
Fitosteroles , Rosaceae , Ácidos Grasos , Frutas , Genotipo , Aceites de Plantas , Tocoferoles
8.
J Sci Food Agric ; 102(2): 488-495, 2022 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-34138466

RESUMEN

BACKGROUND: The exact mechanism of lipid autoxidation in vegetable oils, taking into account physical aspects of this phenomenon, including the role of association colloids, is still not fully understood. The purpose of this study was to consider changes in moisture content and DOPC phospholipid (1,2-dioleoyl-sn-glycero-3-phosphocholine) critical micelle concentration (CMC) in rapeseed oil during autoxidation as well as to find the relationship between these parameters and the accumulation of primary and secondary lipid oxidation products. RESULTS: The experiments were performed at initial oil humidity 220 ppm and 700 ppm, with DOPC below and above CMC. The increase in water concentration was favored by the presence of phospholipids above CMC and, at the same time, high initial water level, which favored oxidation processes and the creation of amphiphilic autoxidation products. At relatively high water level and low amphiphilic DOPC concentration, the growth of water content does not affect the concentration of oxidation products. CONCLUSION: Amphiphilic substances play a significant role in increasing the water content of oil. Autoxidation products may reduce CMC of DOPC, but water is able to compensate for the CMC-reducing effect of oxidation products. The presence of association colloids and initial water content play a crucial role in the oxidation process of rapeseed oil. The increase in water concentration does not cause a sufficiently large increase in the number of micelles or sufficiently significant changes in their structure to effect an increase in the level of oxidation products. The formation of micelles requires an appropriate content of both water and amphiphilic substances derived from seeds (phospholipids). © 2021 Society of Chemical Industry.


Asunto(s)
Fosfolípidos/química , Aceite de Brassica napus/química , Agua/análisis , Coloides/química , Micelas , Oxidación-Reducción
9.
Sensors (Basel) ; 21(8)2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33923662

RESUMEN

This paper presents the analyses of the effect of fiber additives on volatile organic compounds in bread. The bread was baked from wheat flour with the addition of 3% of fruit fiber, following common procedures. After baking, volatile organic compounds contained in the control bread and breads supplemented with cranberry, apple, and chokeberry fiber were determined. The SPME/GC-MS technique was used for the identification of the odor profile, and the electronic nose Agrinose (e-nose) was used to assess the intensity of the aroma. The results of the analyses revealed the profile of volatile organic compounds in each experimental variant, which was correlated with responses of the electronic nose. The results indicate that the volatile compound profile depends on the bread additives used and influences the intensity of bread aroma. Moreover, the profile of volatile organic compounds in terms of their amount and type, as well as the intensity of their interaction with the active surface of the electrochemical sensors, was specific exclusively for the additive in each case.


Asunto(s)
Harina , Compuestos Orgánicos Volátiles , Pan/análisis , Suplementos Dietéticos , Harina/análisis , Frutas , Odorantes , Triticum
10.
Molecules ; 26(5)2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33806318

RESUMEN

The formation of Maillard reaction products (MRPs) in gluten-free bread made from roasted and raw buckwheat flour was examined. The levels of phenolic compounds such as flavonoids (catechin, naringenin, quercetin, rutin, and others) and phenolic acids (like 4-hydroxybenzoic, caffeic, dihydroxybenzoic, ferulic, gallic, syringic, vanillic, and p-coumaric) were measured using reversed-phase ultra-high performance liquid chromatography-electrospray ionization mass spectrometry (RP-UHPLC-ESI-MS). Early and advanced Maillard reaction products were analyzed using HPLC, whereas spectrofluorimetric analysis was used to determine the levels of fluorescent intermediate compounds (FIC). The total levels of phenolic compounds were higher in the case of buckwheat bread prepared from roasted buckwheat flour (156 and 140 µg/g of crumb and crust, respectively). Rutin, gallic acid, and catechin were the most abundant phenolic compounds detected in roasted buckwheat bread. The roasting process resulted in significantly lower radical scavenging capacities (ABTS) of the total phenolics and flavonoids in the buckwheat bread. Taking into consideration these Maillard reaction products, we observed a significant increase in FIC level in roasted buckwheat crumb and crust (at about 40%, and 38%, respectively). At the same time, the Nε-(carboxymethyl)lysine (CML) level did not change in roasted or raw buckwheat bread crumb, though in roasted buckwheat crust the concentration of CML increased by about 21%.


Asunto(s)
Antioxidantes/análisis , Dieta Sin Gluten , Fagopyrum/química , Flavonoides/análisis , Harina/análisis , Fenoles/análisis , Reacción de Maillard
11.
Food Chem ; 346: 128888, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33385911

RESUMEN

The aim of this study was to analyse contents of phytosterols, carotenoids, tocochromanols and fatty acid composition in oil from nutlets of linden. Standard determination methods for these compounds were applied using liquid and gas chromatography. In the analysed oils from small and large-leaved lime the dominant acids included linoleic (53.1 and 54.1%), oleic (18.5 and 22.2%), palmitic (15.3 and 11.8%). Linden seed oil was characterised by very high contents of phytosterols (2-2.5 g/100 g). ß-Sitosterol was the dominant phytosterol (80-83%). Additionally squalene was detected at 806 and 607 mg/100 g, respectively, for Tilia cordata and T.platyphyllos. It was found that linden seed oil contains tocopherols (93%) and tocotrienols (7%). In terms of tocochromanol contents this oil is surpassed only by wheat germ oil. In terms of the α-T equivalent these oils contain 95 (Tilia cordata) and 50.6 mg/100 g vitamin E (Tilia platyphyllos).


Asunto(s)
Carotenoides/análisis , Tilia/química , Tocoferoles/análisis , Tocotrienoles/análisis , Cromatografía de Gases , Cromatografía Líquida de Alta Presión , Ácidos Grasos/análisis , Aceites de Plantas/química , Semillas/química , Semillas/metabolismo , Tilia/metabolismo
12.
J Sci Food Agric ; 100(1): 354-361, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31588554

RESUMEN

BACKGROUND: Postharvest processing, including drying, has a significant effect on the processability of oil crop seeds. High drying air temperature may significantly affect the levels of bioactive compounds in plant raw materials. We decided to investigate the subject given the lack of data on the drying of mustard seeds. The aim was to determine the effect of drying temperature on free fatty acid, phytosterol and tocopherol levels in the oil obtained from white mustard seeds. Seeds were dried in a thin layer at 40, 60, 80, 100, 120 and 140 °C. Changes in phytosterol levels were assessed using gas chromatography-mass spectrometry and changes in tocopherol levels by high-performance liquid chromatography. RESULTS: The analysis showed that, upon completion of air drying at 40-100 °C, losses of sterols did not exceed 5%, while upon completion of drying at 120 °C and 140 °C these losses amounted to 17-50%. Our investigation also showed that during drying of white mustard seed the total tocopherol levels increased, and the higher the drying temperature, the greater the increment. In seeds air-dried at 120 °C and 140 °C, the increase in tocopherol amounted to 7-9%. CONCLUSION: We also showed that the temperature of the drying agent significantly affects the tocopherol and phytosterol levels. It was found that a maximum temperature of 100 °C provides optimal drying conditions for mustard seeds. Principal component analysis identified two subgroups of oils obtained from seeds dried at 120 °C and 140 °C, which differed considerably from the other samples in terms of their bioactive component contents. © 2019 Society of Chemical Industry.


Asunto(s)
Desecación/métodos , Fitosteroles/análisis , Extractos Vegetales/análisis , Semillas/química , Sinapis/química , Tocoferoles/análisis , Cromatografía de Gases y Espectrometría de Masas , Temperatura , Vitamina E/análisis
13.
Molecules ; 24(24)2019 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-31842452

RESUMEN

The aim of the study was to analyze the influence of the surface area to volume ratio of pressed and refined rapeseed oils on the changes in tocopherol content and polymerization of triacylglycerols during heating. In the study the pressed and refined rapeseed oil was heated at 170 °C, during 6, 12, and 18 h with three different surface area to volume (s/v) ratios (0.378, 0.189, and 0.126 cm-1). During heating, a decrease in tocopherols and increases in dimers, trimers, and oligomers of triacylglycerols were observed. However, the changes were dependent on the surface area to volume ratio used, type of oil and time of heating. The biggest changes were observed in oil with the biggest s/v ratio (0.378 cm-1), and the lowest when the s/v ratio was 0.126 cm-1. The pressed oil was characterized by faster degradation of tocopherols and slower increase of triacylglycerol polymer levels compared to refined oil.


Asunto(s)
Calor , Polimerizacion , Aceite de Brassica napus/química , Tocoferoles/química , Triglicéridos/química
14.
Nutrients ; 11(7)2019 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-31277482

RESUMEN

Potato protein is recognized as one of the most valuable nonanimal proteins due to the high content of essential amino acids. So far, it has not been used in human nutrition on a large scale due to technological limitations regarding its acquisition. In this study, the protein fraction of potato juice was concentrated with the use of membrane separation. The obtained potato juice protein concentrate (PJPC) was characterized in terms of nutritional value and biological activity, and the amino acid composition, mineral content, and antioxidant properties were determined. Moreover, in vitro cytotoxic activity against cancer cells of the gastrointestinal tract was investigated. The results of the present study indicate that PJPC is an excellent source of lysine and threonine, while leucine is its limiting amino acid, with an amino acid score (AAS) of 65%. Moreover, PJPC contains substantial amounts of Fe, Mn, K, and Cu. As demonstrated experimentally, PJPC is also characterized by higher antioxidant potential than potato itself. Biological activity, however, is not limited to antioxidant activity alone. Cytotoxicity studies using a gastric cancer cell line (Hs 746T), a colon cancer cell line (HT-29), and human colon normal cells (CCD 841 CoN) proved that PJPC is characterized by selective activity against cancer cells. It can thus be concluded that the developed method of producing protein concentrate from potato juice affords a product with moderate nutritional value and interesting biological activity.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Proteínas en la Dieta/análisis , Jugos de Frutas y Vegetales/análisis , Neoplasias Gastrointestinales/tratamiento farmacológico , Valor Nutritivo , Raíces de Plantas/química , Solanum tuberosum/química , Antineoplásicos Fitogénicos/análisis , Antioxidantes/análisis , Benzotiazoles/química , Supervivencia Celular/efectos de los fármacos , Manipulación de Alimentos/métodos , Neoplasias Gastrointestinales/patología , Células HT29 , Humanos , Ácidos Sulfónicos/química
15.
Acta Sci Pol Technol Aliment ; 18(2): 205-218, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31256548

RESUMEN

BACKGROUND: The basic parameter influencing the quality of cold-pressed oil is the quality of seeds used  for pressing. Adverse moisture content and storage temperature of rape seeds may affect the quality of oil obtained from them. This paper presents the effects of increased rapeseed moisture content on the quality of the oil pressed. METHODS: The material used for the tests was rapeseed (canola) cv. PR 46 W14. The moisture content of the seeds was adjusted to 10%, 12% and 20%, and the seeds were stored at room temperature for 14 days. The samples were then dried to a seed moisture equal to 7% and oil was pressed from them. Acid and peroxide values, as well as the content of water, tocopherols and phenolic acids, were determined. In addition, a sensory analysis of the oil samples was carried out, and structural changes in the association colloids in the oil were determined using a fluorescent probe. RESULTS: With the increase in seed moisture, the increase in peroxide and acid values of the analyzed oils was recorded. A slight decrease in tocopherol content and a significant increase in phenolic acid concentration, depending on the seed moisture content, was observed. Sensory analysis showed odor sensory profile changes that probably indicate microflora development. CONCLUSIONS: The rapeseed moisture content has a crucial influence on the quality of oil obtained from them. Along with an increase in seed moisture, the possibility of developing undesirable microflora grows, which results in a deterioration in the quality of the obtained oil.


Asunto(s)
Brassica napus/química , Manipulación de Alimentos/métodos , Fenoles/análisis , Aceite de Brassica napus/química , Semillas/química , Tocoferoles/análisis , Agua/análisis , Brassica napus/microbiología , Frío , Microbiología de Alimentos , Humanos , Odorantes , Presión , Semillas/microbiología
16.
Open Life Sci ; 14: 150-157, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33817147

RESUMEN

Potato juice (PJ), commonly considered a burdensome waste, is rich in various compounds with bioactive properties. It has long been considered a remedy for gastric problems in traditional folk medicine. If valorization of PJ through implementation in the production of functional foods is to be considered, stabilization methods must be developed to allow long-term storage of this seasonal product. It is important that such methods are chosen with regard to their effect on the bioactive value of the obtained product. In this study, the impact of four stabilization methods on the antioxidant and cytotoxic activities of PJ was investigated. Elevated temperatures were used in thermal deproteinization used to obtain DPJW (deproteinated potato juice water) and spray-drying of FPJ (fresh potato juice) that resulted in SDPJ. Freeze drying and cryoconcentration were the low temperature processing methods that yielded PJL (potato juice lyophilisate) and CPJ (cryocorncentrated potato juice), respectively. All processed materials were characterized chemically and compared with raw materials in terms of phenolic compounds content, antioxidant activity as well as cytotoxicity to human tumor cells isolated from the gastric mucosa (Hs476T cell line), colon (Caco-2 and HT-29 cell lines), and normal cells isolated from the small intestine and colon epithelium (IEC-6 and NCM460 cell lines). It was stated that high-temperature processes - thermal deproteinization and spray-drying - yielded products with increased antioxidant potential (TEAC) that also showed increased cytotoxic activity towards intestinal cancer cells. At the same time the cytotoxicity towards normal cells remained on par with that of fresh PJ (IEC-6 cells) or decreased (NCM460 cells). Thermal deproteinization significantly decreased the content of glycoalcaloids in the juice, while spray drying did not have such an effect. The two low-temperature processes investigated - cryoconcentration and freeze drying - did not affect the PJ cytotoxic activity towards any of the cell lines used in the tests, whereas they did affect the antioxidant properties and glycoalcaloids content of PJ.

17.
Acta Sci Pol Technol Aliment ; 17(4): 367-375, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30558393

RESUMEN

BACKGROUND: The quality of rapeseed oil depends to a considerable degree on raw material quality. Negli- gence in maintaining the appropriate conditions during long-term rapeseed storage (excessively high humid- ity and temperature) may contribute to a deterioration of seed quality, as a result of microbial growth and changes in native antioxidant contents. The aim of this study was to investigate the effect of inappropriate storage conditions on changes in sinapic acid derivative content, which is the main phenolic compound in rapeseeds. METHODS: The material used for tests was canola cv. PR 46 W14. Seeds with a 13.5% moisture content were stored for 21 days in a thermo-hygrostat chamber, ensuring rapeseed storage under constant humidity and temperature conditions. In this study, the level of mould fungi was analysed using the plate method, while those of sinapic acid derivatives were determined using the HPLC-DAD method. RESULTS: Intensive growth of mould fungi in the rapeseeds was observed after 6 days of storage. Changes were recorded in sinapic acid derivative contents, which are the main phenolic compounds in rapeseed. The level of phenolic compounds found in the bound form (sinapin; sinapic acid methyl ester; 1,2-disinapoyl- dihexoside; 1,2-disinapoyl-hexoside and 1,2,2’-trisinapoyl-dihexoside) decreased. At the same time, an in- crease was recorded in trans-sinapic acid content (by 63%). CONCLUSIONS: Both qualitative and quantitative changes in phenolic compounds may be connected with the development of fungal microflora in stored rapeseeds. Only adequate storage conditions for the oil raw mate- rial, such as rapeseeds, may ensure good quality in the final product, in this case, rapeseed oil.


Asunto(s)
Brassica napus/química , Ácidos Cumáricos/análisis , Almacenamiento de Alimentos , Fenoles/análisis , Semillas/química , Antioxidantes/análisis , Brassica napus/microbiología , Microbiología de Alimentos , Hongos , Aceite de Brassica napus/química
18.
Acta Sci Pol Technol Aliment ; 16(3): 293-301, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29055977

RESUMEN

BACKGROUND: Pumpkin seed oil is valuable oil for its distinctive taste and aroma, as well as supposed health- promoting properties. The aim of this study was to investigate how roasting pumpkin seeds influences the physicochemical properties of cold-pressed oils. METHODS: The fatty acid composition, content of phytosterols, carotenoids and tocopherols, oxidative stability and colour were determined in oils after cold pressing and storage for 3 months using GC-FID, GCxGC-ToFMS, HPLC, Rancimat and spectrophotometric methods. RESULTS: The results of this study indicate that the seed-roasting and storage process have no effect on the fatty acid composition of pumpkin seed oils, but does affect phytosterols and tocopherols. The carotenoid content decreased after storage. The colour of the roasted oil was darker and changed significantly during storage. CONCLUSIONS: Pumpkin oil obtained from roasted seeds shows better physicochemical properties and oxidative stability than oil from unroasted seeds.


Asunto(s)
Culinaria , Cucurbita/química , Manipulación de Alimentos/métodos , Aceites de Plantas/química , Semillas/química , Análisis de los Alimentos , Oxidación-Reducción
19.
Acta Sci Pol Technol Aliment ; 16(1): 69-81, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28362474

RESUMEN

BACKGROUND: The paper looks at the levels of canolol, tocopherols and antioxidant activity in cold-pressed and hot-pressed rapeseed oils produced from seeds of various moisture levels (5%, 7.5%, and 10%). The paper also considers the effects of seed roasting on the levels of these compounds. METHODS: The material used for the tests was rapeseed cv. Adrianna. The quality of the oils obtained is determined using peroxide and acid values. The levels of canolol and tocopherols are analyzed using HPLC. The DPPH radical-scavenging activity method for oil samples and phenolic extract from oils was used. RESULTS: It has been demonstrated that the oils produced from rapeseeds with a 5% moisture content, and   in particular from cold-pressed oils, were characterized by the lowest peroxide values. Cold-pressed oils produced from rapeseeds with a 5% moisture content were characterized by higher levels of tocopherols and plastochromanol-8. In the case of hot-pressed oils, the highest levels of tocopherols were found in oils pro- duced from seeds with a 7.5% moisture content, and the greatest amount of PC-8 (more than 4 mg/100 g) was found in oils produced from seeds with a 10% moisture content. Hot-pressed oils have been shown to have higher levels of these compounds than cold-pressed oils. Both roasting and hot pressing led to an increase in the amount of canolol in the oils investigated. When analysing the antioxidant activity of the oils and phenolic extracts it was shown that phenolic compounds are responsible for approx. 10% of total antioxidant activity. CONCLUSIONS: Various levels of biologically active compounds were shown to be present in the rapeseed oil obtained from raw materials of a varying moisture content. The type of pressing process (cold-pressing or hot-pressing) and whether the seeds have undergone roasting has also been shown to affect the resulting oil and the level of native antioxidants it contains.


Asunto(s)
Antioxidantes/análisis , Manipulación de Alimentos/métodos , Fenoles/análisis , Aceites de Plantas/química , Tocoferoles/análisis , Compuestos de Vinilo/análisis , Cromanos/análisis , Aceite de Brassica napus , Semillas/química , Temperatura , Vitamina E/análogos & derivados , Vitamina E/análisis
20.
Food Chem ; 231: 175-184, 2017 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-28449994

RESUMEN

This study had the objective of determining the antiglycation activity of phenolic compounds (PCs) ((+)-catechin, quercetin, gallic, ferulic, and caffeic acids) added to a model bread with regards to the inhibition of Nε-(carboxymethyl)lysine (CML) formation. PCs were found to significantly reduce CML (31.77%-87.56%), even at the lowest concentration, with the exception of ferulic acid (FA). The strongest inhibitory effect of FA (∼62%) appeared when concentration was increased to 1.0g/100g of flour. The available lysine losses (0.00%-90.51%) showed a significant correlation (0.853-0.990) with effectiveness of CML inhibition, except in the case of samples with FA. (+)-Catechin reduced CML levels the most, probably due to its structure-antioxidant activity relationship, its thermal stability (∼51% loss), and its reactivity with ε-lysine side chains (∼40.77% loss). Although the bread supplemented with PCs contained low levels of CML, this process may adversely affect bread flavor, reducing the formation of pyrazines (1.10%-80.77%).


Asunto(s)
Pan , Pirazinas , Catequina , Lisina/análogos & derivados , Reacción de Maillard , Fenoles
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