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1.
Molecules ; 28(21)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37959822

RESUMO

Lately, the essential oils industry has been one of the most expanding markets globally. However, the byproducts generated after the distillation of aromatic plants and their transformation to novel high-added value products consist of a major up-to-date challenge. Thus, the scope of the current study is the optimization of ultrasound-assisted extraction (UAE) for the recovery of phenolic compounds from rose (Rosa damascena) post-distillation side streams using Box-Behnken design. In particular, the highest total phenolic content (TPC) was achieved at 71% v/v ethanol-water solution, at 25 min, 40 mL/g dry sample and 53% ultrasound power, while ethanol content and extraction time were the most crucial factors (p-value ≤ 0.05) for UAE. Both solid (RSB) and liquid (LSB) rose side streams exhibited significant antiradical and antioxidant activities. The interpretation of attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectra confirmed the presence of compounds with properties such as phenolic compounds, phenolic amide derivatives, and alcohols in the extracts. Moreover, the flavonoids naringenin, quercetin, and kaempferol were the major phenolic compounds, identified in the extracts by liquid chromatography-tandem mass spectrometry analysis (LC-MS/MS), followed by gallic, protocatechuic, p-hydroxybenzoic, and rosmarinic acids. Furthermore, the LC-MS/MS results pinpointed the effect of factors other than the extraction conditions (harvesting parameters, climatic conditions, plant growth stage, etc.) on the phenolic fingerprint of RSB extracts. Therefore, RSB extracts emerge as a promising alternative antioxidant agent in food products.


Assuntos
Antioxidantes , Rosa , Antioxidantes/química , Cromatografia Líquida , Rios , Extratos Vegetais/química , Espectrometria de Massas em Tandem , Fenóis/química , Etanol/química
2.
Molecules ; 28(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36677576

RESUMO

The conversion of plant byproducts, which are phenolic-rich substrates, to valuable co-products by implementing non-conventional extraction techniques is the need of the hour. In the current study, ultrasound- (UAE) and microwave-assisted extraction (MAE) were applied for the recovery of polyphenols from peach byproducts. Two-level screening and Box-Behnken design were adopted to optimize extraction efficiency in terms of total phenolic content (TPC). Methanol:water 4:1% v/v was the extraction solvent. The optimal conditions of UAE were 15 min, 8 s ON-5 s OFF, and 35 mL g-1, while MAE was maximized at 20 min, 58 °C, and 16 mL g-1. Regarding the extracts' TPC and antioxidant activity, MAE emerged as the method of choice, whilst their antiradical activity was similar in both techniques. Furthermore, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to determine chlorogenic acid and naringenin in byproducts' extracts. 4-Chloro-4'-hydroxybenzophenone is proposed as a new internal standard in LC-MS/MS analysis in foods and byproducts. Chlorogenic acid was extracted in higher yields when UAE was used, while MAE favored the extraction of the flavonoid compound, naringenin. To conclude, non-conventional extraction could be considered as an efficient and fast alternative for the recovery of bioactive compounds from plant matrices.


Assuntos
Prunus persica , Cromatografia Líquida , Espectrometria de Massas em Tandem/métodos , Micro-Ondas , Projetos de Pesquisa , Ácido Clorogênico , Extratos Vegetais/química , Fenóis/química , Antioxidantes/química
3.
Int J Mol Sci ; 23(8)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35456888

RESUMO

Advances in sequencing technologies over the past 15 years have led to a substantially greater appreciation of the importance of the gut microbiome to the health of the host. Recent outcomes indicate that aspects of nutrition, especially lipids (exogenous or endogenous), can influence the gut microbiota composition and consequently, play an important role in the metabolic health of the host. Thus, there is an increasing interest in applying holistic analytical approaches, such as lipidomics, metabolomics, (meta)transcriptomics, (meta)genomics, and (meta)proteomics, to thoroughly study the gut microbiota and any possible interplay with nutritional or endogenous components. This review firstly summarizes the general background regarding the interactions between important non-polar dietary (i.e., sterols, fat-soluble vitamins, and carotenoids) or amphoteric endogenous (i.e., eicosanoids, endocannabinoids-eCBs, and specialized pro-resolving mediators-SPMs) lipids and gut microbiota. In the second stage, through the evaluation of a vast number of dietary clinical interventions, a comprehensive effort is made to highlight the role of the above lipid categories on gut microbiota and vice versa. In addition, the present status of lipidomics in current clinical interventions as well as their strengths and limitations are also presented. Indisputably, dietary lipids and most phytochemicals, such as sterols and carotenoids, can play an important role on the development of medical foods or nutraceuticals, as they exert prebiotic-like effects. On the other hand, endogenous lipids can be considered either prognostic indicators of symbiosis or dysbiosis or even play a role as specialized mediators through dietary interventions, which seem to be regulated by gut microbiota.


Assuntos
Microbioma Gastrointestinal , Carotenoides/farmacologia , Gorduras na Dieta/farmacologia , Lipidômica , Esteróis/farmacologia
4.
Molecules ; 27(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35408586

RESUMO

Wine lees, a sub-exploited byproduct of vinification, is considered a rich source of bioactive compounds, such as (poly)phenols, anthocyanins and tannins. Thus, the effective and rapid recovery of these biomolecules and the assessment of the bioactive properties of wine lees extracts is of utmost importance. Towards this direction, microwave-assisted extraction (MAE) factors (i.e., extraction time, microwave power and solvent/material ratio) were optimized using experimental design models in order to maximize the (poly)phenolic yield of the extracts. After optimizing the MAE process, the total phenolic content (TPC) as well as the antiradical, antioxidant and antimicrobial activity of the extracts were evaluated. Furthermore, Fourier transform infrared spectroscopy (FTIR) was employed to investigate the chemical profile of wine lees extracts. Red varieties exhibited higher biological activity than white varieties. The geographical origin and fermentation stage were also considered as critical factors. The white variety Moschofilero presented the highest antioxidant, antiradical and antimicrobial activity, while Merlot and Agiorgitiko samples showed noteworthy activities among red varieties. Moreover, IR spectra confirmed the presence of sugars, amino acids, organic acids and aromatic compounds. Thus, an efficient, rapid and eco-friendly process was proposed for further valorization of wine lees extracts.


Assuntos
Anti-Infecciosos , Vinho , Antocianinas/análise , Anti-Infecciosos/farmacologia , Antioxidantes/química , Micro-Ondas , Fenóis/química , Extratos Vegetais/farmacologia , Vinho/análise
5.
Molecules ; 26(9)2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066449

RESUMO

The scope of this work is the study of a combined process including a dipping step into an oregano (Origanum vulgare ssp. hirtum) infusion (OV) followed by osmotic treatment of chicken fillets at 15 °C. Chicken fillets were immersed in an osmotic solution consisting of 40% glycerol and 5% NaCl with (OV/OD) and without (OD) prior antioxidant enrichment in a hypotonic oregano solution. A comparative shelf life study of all the samples (untreated, OD and OV/OD treated) was then conducted at 4 °C in order to assess the impact of this process on the quality and shelf life of chilled chicken fillets. Microbial growth, lipid oxidation and color/texture changes were measured throughout the chilled storage period. Rates of microbial growth of pretreated fillets were significantly reduced, mainly as a result of water activity decrease (OD step). Rancidity development closely related to off odors and sensory rejection was greatly inhibited in treated fillets owing to both inhibitory factors (OD and OV), with water-soluble phenols (OV step) exhibiting the main antioxidant effect. Shelf life of treated chicken fillets exhibited a more than three-fold increase as compared to the untreated samples based on both chemical and microbial spoilage indices, maintaining a positive and pleasant sensory profile throughout the storage period examined.


Assuntos
Antioxidantes/química , Análise de Alimentos/métodos , Carne/análise , Óleos Voláteis/química , Origanum/química , Animais , Galinhas , Cor , Manipulação de Alimentos , Conservação de Alimentos , Tecnologia de Alimentos/métodos , Cinética , Peroxidação de Lipídeos , Lipídeos/química , Músculos/metabolismo , Odorantes , Osmose , Fenóis/química , Temperatura
6.
Molecules ; 25(11)2020 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-32545179

RESUMO

Traditional extraction remains the method-of-choice for phytochemical analyses. However, the absence of an integrated analytical platform, focusing on customized, validated extraction steps, generates tendentious and non-reproducible data regarding the phytochemical profile. Such a platform would also support the exploration and exploitation of plant byproducts, which are a valuable source of bioactive metabolites. This study deals with the incorporation of (a) the currently sub-exploited high energy extraction methods (ultrasound (UAE)- and microwave-assisted extraction (MAE)), (b) experimental design (DOE), and (c) metabolomics, in an integrated analytical platform for the extensive study of plant metabolomics and phytochemical profiling. The recovery of carotenoids from apricot by-products (pulp) is examined as a case study. MAE, using ethanol as solvent, achieved higher carotenoid yields compared to UAE, where 1:1 chloroform-methanol was employed, and classic extraction. Nuclear magnetic resonance (NMR)-based metabolomic profiling classified extracts according to the variations in co-extractives in relation to the extraction conditions. Extracts with a lower carotenoid content contained branched-chain amino acids as co-extractives. Medium carotenoid content extracts contained choline, unsaturated fatty acids, and sugar alcohols, while the highest carotenoid extracts were also rich in sugars. Overall, the proposed pipeline can provide different the phytochemical fractions of bioactive compounds according to the needs of different industrial sectors (cosmetics, nutraceuticals, etc.).


Assuntos
Aminoácidos de Cadeia Ramificada/isolamento & purificação , Carotenoides/isolamento & purificação , Metabolômica/métodos , Prunus armeniaca/química , Fracionamento Químico , Espectroscopia de Ressonância Magnética , Micro-Ondas , Compostos Fitoquímicos/química , Metabolismo Secundário , Ultrassonografia
7.
Molecules ; 25(4)2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32075327

RESUMO

Complex formation is among the mechanisms affecting metal bioaccessibility. Hence, the quantification of organic metal complexation in food items is of interest. Organic ligands in solutions of environmental and/or food origin function as buffering agents against small changes in dissolved metal concentrations, being able to maintain free metal ion concentrations below the toxicity threshold. Organic matter in vinegars consists of bioactive compounds, such as polyphenols, Maillard reaction endproducts, etc., capable of complexing metal ions. Furthermore, transition metal ions are considered as micronutrients essential for living organisms exerting a crucial role in metabolic processes. In this study, differential pulse anodic stripping voltammetry (DPASV), a sensitive electrochemical technique considered to be a powerful tool for the study of metal speciation, was applied for the first time in vinegar samples. The concentrations of Cu complexing ligands (LT) in 43 vinegars retailed in Greece varied between 0.05 and 52 µM, with the highest median concentration determined in balsamic vinegars (14 µM), compared to that of common vinegars (0.86 µM). In 21% of the vinegar samples examined, LT values were exceeded by the corresponding total Cu concentrations, indicating the presence of free Cu ion and/or bound within labile inorganic/organic complexes. Red grape balsamic vinegars exhibited the highest density of Cu ligands per mass unit of organic matter compared to other foodstuffs such as herbal infusions, coffee brews, and beers. Among the 16 metals determined in vinegars, Pb is of particular importance from a toxicological point of view, whereas further investigation is required regarding potential Rb biomagnification.


Assuntos
Ácido Acético/química , Complexos de Coordenação/química , Cobre/análise , Análise de Alimentos/métodos , Polifenóis/química , Oligoelementos/análise , Cerveja/análise , Cátions Bivalentes , Café/química , Técnicas Eletroquímicas , Grécia , Humanos , Concentração de Íons de Hidrogênio
8.
J Sci Food Agric ; 99(2): 781-789, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-29998566

RESUMO

BACKGROUND: Photovoltaics (PV) provide an alternative solution to cover energy demands in greenhouses. This study evaluates the effect of PV panels installed on the roofs of greenhouses, and the partial shading that they cause, on the growth parameters and growth indicators of the experimental cultivation of peppers (Capsicum annuum cv. California Wonder). The growth of the plants, the antioxidant profile, radical scavenging activity, total phenolic content, and the phenolic and metabolic profiles (using LC-MS spectrometry and NMR spectroscopy) are evaluated. RESULTS: Data are presented from a full cultivation period. Results indicated that indoor temperatures were similar for both glass and glass-PV (glass with PV panels installed) greenhouses during the day and the night. The production yield was higher for the glass-PV greenhouses. The pepper fruits' weight, dimensions, and thickness were similar in both cases. Comparison of the pepper fruit extracts in terms of total phenolic content, antioxidant, and antiradical activities indicated differences that were not statistically significant. Photometric and spectroscopic studies both showed a smaller distribution of values in the case of the glass-PV greenhouse, probably indicating a more consistent phytochemical profile. CONCLUSION: Covering only a small proportion (ca. 20%) of the greenhouse roof with photovoltaic panels contributes considerably to its energy demands without affecting plant growth and quality. © 2018 Society of Chemical Industry.


Assuntos
Capsicum/crescimento & desenvolvimento , Produção Agrícola/métodos , Antioxidantes/análise , Capsicum/química , Capsicum/efeitos da radiação , Produção Agrícola/instrumentação , Frutas/química , Frutas/crescimento & desenvolvimento , Frutas/efeitos da radiação , Luz , Fenóis/análise , Verduras/química , Verduras/crescimento & desenvolvimento , Verduras/efeitos da radiação
9.
J Food Sci Technol ; 52(6): 3264-72, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26028707

RESUMO

Laetiporus sulphureus is a saprophyte belonging to a specific group of wood-decomposing Basidiomycetes growing on deciduous trees. This fungus has been characterized as a herbal medicine and is also known for its antimicrobial properties. In the present study, high energy extraction techniques using different solvents were compared to obtain maximum yield of the edible fungus Laetiporus sulphureus total lipids. The lipid classes and fatty acid composition of the fruiting bodies' total lipids has been studied using GC-FID and Iatroscan TLC-FID analysis. Among the lipids, the neutral lipids predominated followed by phospholipids and glycolipids. Triglycerides were the most abundant in the neutral lipid fraction, whereas phosphatidylcholine in phospholipids. The existence of relatively high amount of sterols may be correlated to fungus pharmaceutical properties. Total lipids were found to contain high unsaturated degree fatty acids (UFA/SFA>3.4) and dominated of C18:2ω-6, C18:1ω-9 and C16:0 fatty acids. Antibacterial and antifungal properties of mushrooms' lipid extracts from two different solvents were also examined. Results indicated that hexane extracts possessed better antifungal and slightly better antibacterial activity compared to chloroform extracts though both were less active than the commercial antimicrobial agents.

10.
Foods ; 13(2)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38254534

RESUMO

The aim of the present study was to evaluate Marisol strawberries' (Fragaria × ananassa) physicochemical quality and shelf-life during storage, using an integrated analytical approach. More specifically, the research aimed to assess the strawberries' color, texture, and nutritional quality, over an 11-day storage period, employing physicochemical analyses, spectrophotometric assays, Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) spectroscopy, image analysis, and statistical tools. The results revealed significant changes in the outer surface texture and color characteristics, indicating spoilage progression. Physicochemical parameters such as water activity, moisture content, soluble solids, titratable acidity, and ascorbic acid content exhibited significant alterations, influencing the taste profile and freshness perception. Antioxidant and antiradical activities showed fluctuations, suggesting a potential decrease in phenolic content during storage. Moreover, the ATR-FTIR spectra findings confirmed the results regarding the moisture content, soluble solids, and total phenolic content. The integration of physicochemical and image analysis-derived features through a principal component analysis (PCA) enabled the accurate classification of samples based on storage days. Regression analysis, using these features, successfully predicted the storage day with high accuracy. Overall, this integrated analytical approach provided valuable information on the estimation of Marisol strawberries' shelf-life and the prediction of their quality deterioration, contributing to better fruit management and the minimization of discards.

11.
Foods ; 13(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38611323

RESUMO

Despite the inherent stability of dried and cured products, such as pastourma, appropriate refrigeration remains essential for preserving their optimal characteristics. This study explored quality and safety characteristics in lamb, beef, and buffalo pastourma during 16-day refrigeration storage after package opening. The comprehensive approach employed Attenuated Total Reflection-Fourier-Transform Infrared (ATR-FTIR) spectroscopy, colorimetry, and image analysis, alongside physicochemical and microbiological analyses, to shed light on these alterations. The findings reveal a reduction in textural uniformity and color vibrancy (fading reds and yellows) across all samples during storage, with lamb pastourma exhibiting the most pronounced effects. Notably, image analysis emerged as a powerful tool, enabling the accurate classification of samples based on storage duration. Additionally, significant variations were observed in moisture content, hue angle, firmness, and TBARS levels, highlighting their influence on pastourma quality. The study documented a gradual decrease in lactic acid bacteria and aerobic plate count populations over time. ATR-FTIR spectra's interpretation revealed the presence of lipids, proteins, carbohydrates, and water. Protein secondary structures, demonstrably influenced by the meat type used, exhibited significant changes during storage, potentially impacting the functional and textural properties of pastourma. Overall, the findings contribute to a deeper understanding of pastourma spoilage during storage, paving the way for the development of improved preservation and storage strategies.

12.
Life (Basel) ; 13(2)2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36836689

RESUMO

Banana ranks as the fifth most cultivated agricultural crop globally, highlighting its crucial socio-economic role. The banana's health-promoting benefits are correlated with its composition in bioactive compounds, such as phenolic compounds. Thus, the present study attempts to evaluate the potential health benefits of banana phenolic content by combing analytical and in silico techniques. Particularly, the total phenolic content and antioxidant/antiradical activity of banana samples during ripening were determined spectrophotometrically. In parallel, liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis was implemented to unravel the variations in the phenolic profile of banana samples during ripening. Chlorogenic acid emerged as a ripening marker of banana, while apigenin and naringenin were abundant in the unripe fruit. In a further step, the binding potential of the elucidated phytochemicals was examined by utilizing molecular target prediction tools. Human carbonic anhydrase II (hCA-II) and XII (hCA-XII) enzymes were identified as the most promising targets and the inhibitory affinity of phenolic compounds was predicted through molecular docking studies. This class of enzymes is linked to a variety of pathological conditions, such as edema, obesity, hypertension, cancer, etc. The results assessment indicated that all assigned phenolic compounds constitute great candidates with potential inhibitory activity against CA enzymes.

13.
Antioxidants (Basel) ; 12(6)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37371914

RESUMO

Coffee is one of the most widely consumed beverages worldwide due to its sensory and potential health-related properties. In the present comparative study, a preparation known as Greek or Turkish coffee, made with different types/varieties of coffee, has been investigated for its physicochemical attributes (i.e., color), antioxidant/antiradical properties, phytochemical profile, and potential biological activities by combining high-throughput analytical techniques, such as infrared spectroscopy (ATR-FTIR), liquid chromatography-tandem mass spectrometry (LC-MS/MS), and in silico methodologies. The results of the current study revealed that roasting degree emerged as the most critical factor affecting these parameters. In particular, the L* color parameter and total phenolic content were higher in light-roasted coffees, while decaffeinated coffees contained more phenolics. The ATR-FTIR pinpointed caffeine, chlorogenic acid, diterpenes, and quinic esters as characteristic compounds in the studied coffees, while the LC-MS/MS analysis elucidated various tentative phytochemicals (i.e., phenolic acids, diterpenes, hydroxycinnamate, and fatty acids derivatives). Among them, chlorogenic and coumaric acids showed promising activity against human acetylcholinesterase and alpha-glucosidase enzymes based on molecular docking studies. Therefore, the outcomes of the current study provide a comprehensive overview of this kind of coffee preparation in terms of color parameters, antioxidant, antiradical and phytochemical profiling, as well as its putative bioactivity.

14.
Curr Res Food Sci ; 4: 937-945, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34934957

RESUMO

Enological tannins are assessed as promising alternative to SO2 in order to control oxidative process during winemaking, due to allergic reactions incurred by sulfite sensitive individuals. In the present study, the commercial enological Tara tannin "Vitanil B″ was added, as alternative to the addition of sulfites, at different concentrations (100-500 mg/L) in white wine from grapes of Vitis vinifera L. var. Malagousia in order to enhance antioxidant stability and sensory character of the wine. Considering photometric analyses and chromatic parameters results, tannin addition (300 mg/L) in Malagousia enhanced total phenolic content, antioxidant and antiradical activity and prevented color deterioration, for a storage period of 100 d, compared to control and sulfited wines. Moreover, aroma quality, body, after taste and overall acceptance of wine treated with 300 mg/L tannin, were highly appreciated and received the highest scores. The overall evaluation of tannin addition was performed by Principal Component Analysis, leading to discrimination of wines, according to photometric, color and sensory analysis parameters. Conclusively, tannin addition resulted in a considerable increase of total phenolic content, antioxidant and antiradical activity, compared to the control and sulfited wines, maintaining the sensory parameters and overall acceptance of Malagousia wine.

15.
J AOAC Int ; 103(2): 413-421, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31530341

RESUMO

The profiles of Vitis vinifera L. and Salvia triloba L. leaf extracts have been studied via photometric assays on the basis of their total phenolic and flavonoid content as well as of their radical scavenging and antioxidant activities. Ultrasound-assisted (UAE) and pressurized liquid extractions (PLE) were implemented for producing polar fractions from the plants, using different methanol-water and glycerol-water mixtures for UAE and PLE, respectively. Aqueous methanol was proved an effective solvent for the UAE of total phenolics and flavonoids as well as for increased radical scavenging and antioxidant activities. As for PLE, plain water was proved a more efficient solvent than hydroglycerolic mixtures. Overall, irrespective of the solvent(s) used, UAE extracts showed higher values compared with the PLE extracts for all the photometric determinations and for both plant species. Moreover, Salvia UAE and PLE extracts presented higher total phenolic and flavonoid contents, accompanied by higher radical scavenging and antioxidant activities, compared with Vitis extracts. The correlations among photometric results were also studied, indicating the categories of compounds that relate to the antioxidant and/or radical scavenging activities of the extracts. Mixtures of the examined extracts could be exploited as the basis of novel phytotherapeutic products in the cosmetic sector.


Assuntos
Salvia , Vitis , Antioxidantes , Flavonoides , Fenóis , Extratos Vegetais , Folhas de Planta
16.
J Food Prot ; 72(3): 556-63, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19343944

RESUMO

Pork meat samples were inoculated with high or low levels (10(6) or 10(3) CFU/g) of Salmonella Enteritidis, vacuum packaged, exposed to gamma radiation (1.0, 2.5, and 4.7 kGy), and stored for 1 month at 4 +/- 1 degrees C. In highly contaminated samples, the target strain was completely eliminated only by the 4.7 kGy radiation dose, whereas in samples at the lower contamination level, 2.5 kGy was sufficient to eliminate Salmonella Enteritidis. The highest of the applied radiation doses reduced the aerobic microflora and extended the sample's refrigeration shelf life by at least 2 weeks. The fatty acid profile of pork meat was not significantly affected by any of the applied radiation doses. Irradiation increased the proportion of saturated fatty acids (SFA) and decreased the content of the polyunsaturated fatty acids (P < 0.05). Irradiation also affected negatively the proportions of the nutritional indexes omega-6/omega-3, SFA/monounsaturated fatty acids, and SFA/polyunsaturated fatty acids. The proportion of the trans fatty acids C18:1omega-9 t9 and C18:2 t9,t12 in the total fatty acids was nearly doubled (90 and 86%, respectively) in the samples that had been exposed to 4.7 kGy. None of the applied radiation doses changed the lightness (L* value) of the meat, but redness (a*) and yellowness (b*) increased, particularly for the samples treated with 4.7 kGy.


Assuntos
Ácidos Graxos/análise , Irradiação de Alimentos/métodos , Conservação de Alimentos/métodos , Carne/microbiologia , Carne/normas , Salmonella enteritidis/crescimento & desenvolvimento , Temperatura Baixa , Contagem de Colônia Microbiana , Qualidade de Produtos para o Consumidor , Relação Dose-Resposta à Radiação , Embalagem de Alimentos/métodos , Raios gama , Humanos , Pigmentação , Salmonella enteritidis/efeitos da radiação , Fatores de Tempo , Vácuo
17.
Food Microbiol ; 26(2): 157-65, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19171257

RESUMO

Feta, a white brine cheese, was produced and contaminated with Listeria monocytogenes. Contamination occurred either at the beginning (pre-process contamination) or at the end of Feta manufacturing (post-process contamination). In the first case the milk was contaminated with 10(3) cfu/ml, and 2 months later, in the final product, the L. monocytogenes population was approximately 10(5) cfu/g. In the second case, the brine (NaCl, 7% w/v), in which the Feta was packaged, was contaminated with 10(3) cfu/ml. Contaminated Feta samples were vacuum-packaged and exposed to irradiation doses of 1.0, 2.5 and 4.7 kGy and stored at 4 degrees C for a month. In the pre-process contaminated samples none of the irradiation doses eliminated L. monocytogenes; however the highest dose reduced the viable population to a level which is in compliance with EC regulations. In the post-process contamination, the 2.5 kGy and 4.7 kGy doses reduced L. monocytogenes counts below the detection limit. Irradiation had no effect on the texture of Feta. Irradiation at 4.7 kGy increased Feta's redness and decreased its yellowness and lightness. Sensorial analyses showed that at the 4.7 kGy dose, the aroma profile of Feta was temporarily affected, since it was restored after 30 days of cold storage.


Assuntos
Queijo/microbiologia , Qualidade de Produtos para o Consumidor , Irradiação de Alimentos/métodos , Conservação de Alimentos/métodos , Raios gama , Listeria monocytogenes/efeitos da radiação , Queijo/normas , Contagem de Colônia Microbiana , Cor , Relação Dose-Resposta à Radiação , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Humanos , Listeria monocytogenes/crescimento & desenvolvimento , Paladar , Temperatura , Fatores de Tempo
18.
Foods ; 8(12)2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31810218

RESUMO

The implementation of Infrared (IR) radiation in heated greenhouses possesses the advantage of high directional control and focused compensation of energy losses, appropriate for creating local microclimate conditions in highly energy-consuming systems, such as greenhouses. Moreover, it can efficiently maintain favorable environmental conditions at the plant canopy. The present study studies the application of Infrared (IR) heating in an experimental greenhouse with eggplant (Solanum melongena L.) cultivation. The experimental results are presented from a full cultivation period inside two identical, small scale experimental greenhouses, with IR and forced air heating system, respectively. The effects of IR heating over plant growth parameters, including the yield of the fruits as well as the total phenolic content and the antioxidant profile of eggplants fruits' extracts are measured and discussed. The results indicate a greater uniformity production in the IR heating greenhouse in terms of antioxidant and radical scavenging activities, as well as the total phenolic content. Moreover, the phenolic profile of eggplant fruits from both greenhouses revealed the existence of numerous bioactive compounds, some of which were only characteristic of the eggplant fruits from IR heated greenhouses.

19.
Foods ; 8(9)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31540465

RESUMO

The objective of this work is the comparative study of different osmotic treatments at 37 °C on the quality and shelf life of chilled sea bass fillets. Fish fillets were treated using osmotic solutions consisting of oligofructose (40%-50%-60%) and 5% NaCl with (BP/OT) and without (OT) former antioxidant enrichment by using Rosa damascena distillation by-products. Water activity decreased to approximately 0.95 after 330 minutes of osmotic treatment. Untreated and osmotically treated fish fillets (BP/OT) and (OT) were subsequently stored at 5 °C and their quality was evaluated based on microbial growth and lipid oxidation. Osmotic treatment extended significantly the shelf life of fish in terms of microbial growth; however, it also accelerated its lipid oxidation. The impregnation of Rosa damascena phenolics not only counterbalanced this negative effect, but led to a more than four-fold increase of the shelf life of sea bass, as compared to the untreated samples.

20.
Chem Phys Lipids ; 152(2): 104-12, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18252200

RESUMO

The concentration of TL in Penaeus kerathurus muscle and cephalothorax was 1.03+/-0.04 (75.9+/-0.8% of which was PhL) and 2.36+/-0.07% (45.5+/-0.8% of which was PhL) of the wet tissue, respectively. The phosphatidylethanolamine represented 26.4+/-0.6% (85.6% diacyl- and 14.4% alkyl-acyl- or alkenyl-acyl-analogues) of muscle and 24.7+/-0.2% (90.7% diacyl- and 9.3% alkyl-acyl- or 1-alkenyl-acyl-analogues) of cephalothorax phospholipids while the phosphatidylcholine represented 57.1+/-0.6% (86.9% diacyl- and 13.1% alkyl-acyl- or alkenyl-acyl-analogues) of muscle and 47.2+/-0.4% (89.1% diacyl- and 10.9% alkyl-acyl- or 1-alkenyl-acyl-analogues) of cephalothorax phospholipids, respectively. The main fatty acids of phosphatidylethanolamine were C16:0, C18:0, C18:1 omega-9, C20:4 omega-6, C20:5 omega-3, C22:6 omega-3 and of phosphatidylcholine were C16:0, C18:0, C18:1 omega-9, C20:4 omega-6, C20:5 omega-3. Low percentages of 2-OH C14:0 and cyclo-17:0 fatty acids were also determined. Phosphatidylethanolamine were found to contain a significantly (P<0.05) higher percentage of polyunsaturated fatty acids compared to phosphatidylcholine. The omega-3/omega-6 ratio in muscle phosphatidylethanolamine and phosphatidylcholine was significantly (P<0.05) higher to the ones of cephalothorax.


Assuntos
Ácidos Graxos/análise , Ácidos Graxos/química , Músculos/metabolismo , Fosfatidilcolinas/química , Fosfolipídeos/química , Tórax/metabolismo , Animais , Bioquímica/métodos , Físico-Química/métodos , Cromatografia em Camada Fina/métodos , Ácidos Graxos Insaturados/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Lipídeos/química , Modelos Estatísticos , Penaeidae , Fosfatidiletanolaminas/química
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