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1.
Molecules ; 29(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38398621

RESUMO

Sardinia, located in Italy, is a significant producer of Protected Designation of Origin (PDO) sheep cheeses. In response to the growing demand for high-quality, safe, and traceable food products, the elemental fingerprints of Pecorino Romano PDO and Pecorino Sardo PDO were determined on 200 samples of cheese using validated, inductively coupled plasma methods. The aim of this study was to collect data for food authentication studies, evaluate nutritional and safety aspects, and verify the influence of cheesemaking technology and seasonality on elemental fingerprints. According to European regulations, one 100 g serving of both cheeses provides over 30% of the recommended dietary allowance for calcium, sodium, zinc, selenium, and phosphorus, and over 15% of the recommended dietary intake for copper and magnesium. Toxic elements, such as Cd, As, Hg, and Pb, were frequently not quantified or measured at concentrations of toxicological interest. Linear discriminant analysis was used to discriminate between the two types of pecorino cheese with an accuracy of over 95%. The cheese-making process affects the elemental fingerprint, which can be used for authentication purposes. Seasonal variations in several elements have been observed and discussed.


Assuntos
Queijo , Animais , Ovinos , Queijo/análise , Zinco/análise , Cobre/análise , Análise Discriminante , Valor Nutritivo
2.
Molecules ; 28(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37298766

RESUMO

Fresh potatoes were deep-fried in olive oil (OO), extra virgin olive oil (EVOO), and their blends with 5%, 10%, and 20% v/v sesame oil (SO). This is the first report on the use of sesame oil as a natural source of antioxidants during olive oil deep frying. The oil was evaluated for anisidine value (AV), free fatty acids (FFAs), extinction coefficient (K232 and K270), Trolox equivalent antioxidant capacity (TEAC), and total phenols (TPs) until the total polar compounds (TPCs) reached 25%. Sesame lignan transformations were monitored through reversed-phase HPLC. While the TPCs in olive oils increased at a steady rate, the addition of 5%, 10%, and 20% v/v SO delayed TPCs' formation for 1, 2, and 3 h, respectively. The addition of 5%, 10%, and 20% v/v SO increased the olive oil frying time by 1.5 h, 3.5 h, and 2.5 h, respectively. The addition of SO to OO reduced the secondary oxidation products' formation rate. The AV for EVOO was lower than OO and all tested blends, even those with EVOO. EVOO was more resistant to oxidation than OO, as measured by the TPCs and TEAC, while the frying time rose from 21.5 to 25.25 h when EVOO replaced OO. The increase in frying time for OO but not for EVOO, after SO addition, points to a niche market for EVOO in deep frying.


Assuntos
Óleos de Plantas , Óleo de Gergelim , Azeite de Oliva , Oxirredução , Antioxidantes/farmacologia
3.
Foods ; 12(12)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37372637

RESUMO

Greece has a long tradition in cheesemaking, with 22 cheeses registered as protected designation of origin (PDO), 1 as protected geographical indication (PGI), and 1 applied for PGI. Several other cheeses are produced locally without any registration, which significantly contribute to the local economy. The present study investigated the composition (moisture, fat, salt, ash, and protein content), color parameters, and oxidative stability of cheeses that do not have a PDO/PGI certification, purchased from a Greek market. Milk and cheese types were correctly assigned for 62.8 and 82.1 % of samples, respectively, through discriminant analysis. The most important factors for milk type discrimination were L, a and b color attributes, salt, ash, fat-in-dry-matter, moisture-in-non-fat-substance, salt-in-moisture, and malondialdehyde contents, whereas a and b, and moisture, ash, fat, moisture-in-non-fat substance contents, and pH were the most influential characteristics for sample discrimination according to cheese type. A plausible explanation may be the differences in milk chemical composition between three animal species, namely cows, sheep, and goats and for the manufacture procedure and ripening. This is the very first report on the proximate analysis of these, largely ignored, chesses aiming to simulate interest for further study and production valorization.

4.
Antioxidants (Basel) ; 12(1)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36671048

RESUMO

Pomegranate is a fruit bearing-plant that is well known for its medicinal properties. Pomegranate is a good source of phenolic acids, tannins, and flavonoids. Pomegranate juice and by-products have attracted the scientific interest due to their potential health benefits. Currently, the medical community has showed great interest in exploiting pomegranate potential as a protective agent against several human diseases including cancer. This is demonstrated by the fact that there are more than 800 reports in the literature reporting pomegranate's anticancer properties. This review is an update on the research outcomes of pomegranate's potential against different types of human diseases, emphasizing on cancer. In addition, perspectives of potential applications of pomegranate, as a natural additive aiming to improve the quality of animal products, are discussed.

5.
Molecules ; 26(9)2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-34066694

RESUMO

Honey consumption is attributed to potentially advantageous effects on human health due to its antioxidant capacity as well as anti-inflammatory and antimicrobial activity, which are mainly related to phenolic compound content. Phenolic compounds are secondary metabolites of plants, and their content in honey is primarily affected by the botanical and geographical origin. In this study, a high-resolution mass spectrometry (HRMS) method was applied to determine the phenolic profile of various honey matrices and investigate authenticity markers. A fruitful sample set was collected, including honey from 10 different botanical sources (n = 51) originating from Greece and Poland. Generic liquid-liquid extraction using ethyl acetate as the extractant was used to apply targeted and non-targeted workflows simultaneously. The method was fully validated according to the Eurachem guidelines, and it demonstrated high accuracy, precision, and sensitivity resulting in the detection of 11 target analytes in the samples. Suspect screening identified 16 bioactive compounds in at least one sample, with abscisic acid isomers being the most abundant in arbutus honey. Importantly, 10 markers related to honey geographical origin were revealed through non-targeted screening and the application of advanced chemometric tools. In conclusion, authenticity markers and discrimination patterns were emerged using targeted and non-targeted workflows, indicating the impact of this study on food authenticity and metabolomic fields.


Assuntos
Antioxidantes/análise , Benzaldeídos/análise , Cinamatos/análise , Flavonoides/análise , Mel/análise , Hidroxibenzoatos/análise , Espectrometria de Massas/métodos , Metaboloma , Metabolômica/métodos , Antioxidantes/isolamento & purificação , Benzaldeídos/isolamento & purificação , Cinamatos/isolamento & purificação , Confiabilidade dos Dados , Flavonoides/isolamento & purificação , Grécia , Humanos , Hidroxibenzoatos/isolamento & purificação , Polônia , Sensibilidade e Especificidade
6.
Antioxidants (Basel) ; 10(2)2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33535708

RESUMO

Mycotoxins appear to be the "Achilles' heel" of the agriculture sector inducing enormous economic losses and representing a severe risk to the health of humans and animals. Although novel determination protocols have been developed and legislation has been implemented within Europe, the side effects of mycotoxins on the homeostatic mechanisms of the animals have not been extensively considered. Feed mycotoxin contamination and the effects on the antioxidant status of livestock (poultry, swine, and ruminants) are presented. The findings support the idea that the antioxidant systems in both monogastrics and ruminants are challenged under the detrimental effect of mycotoxins by increasing the toxic lipid peroxidation by-product malondialdehyde (MDA) and inhibiting the activity of antioxidant defense mechanisms. The degree of oxidative stress is related to the duration of contamination, co-contamination, the synergetic effects, toxin levels, animal age, species, and productive stage. Since the damaging effects of MDA and other by-products derived by lipid peroxidation as well as reactive oxygen species have been extensively studied on human health, a more integrated monitoring mechanism (which will take into account the oxidative stability) is urgently required to be implemented in animal products.

7.
Antioxidants (Basel) ; 10(1)2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33435281

RESUMO

The objective of the present study was to investigate the effect of the natural flavonoid quercetin dietary supplementation on the alteration of egg metallome by applying the basic principles of elemental metabolomics. One hundred and ninety-two laying hens were allocated into 4 treatment groups: the control (C) group that was fed with a commercial basal diet and the other experimental groups that were offered the same diet further supplemented with quercetin at 200, 400 and 800 mg per kg of feed (Q2, Q4 and Q8 group, respectively) for 28 days. The diets contained the same vitamin and mineral premix, thus all birds received the same amount of elements since no differences on feed intake existed. The egg elemental profile consisted of As, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sb, Se, Sr, V, Zn and was determined using inductively coupled plasma mass spectrometry (ICP-MS). Quercetin supplementation altered the elemental profile. Most notably, quercetin altered the element concentrations predominantly in egg shell and albumen. It increased the concentration of Sb while reduced that of Cr and Se in both egg shell and albumen. Moreover, it increased As, Cd in albumen and V in yolk, while compared to the control, reduced As, Cd, Cr, Cu and V and also raised Ca, Fe, Mg and Ni in egg shell. The presence of quercetin led to differentiation of the deposition of certain trace minerals in egg compartments compared to that of hens fed a basal diet, possibly indicating that tailor made eggs for specific nutritional and health requirements could be created in the future.

8.
Metabolites ; 11(2)2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33513809

RESUMO

The national infrastructure FoodOmicsGR_RI coordinates research efforts from eight Greek Universities and Research Centers in a network aiming to support research and development (R&D) in the agri-food sector. The goals of FoodOmicsGR_RI are the comprehensive in-depth characterization of foods using cutting-edge omics technologies and the support of dietary/nutrition studies. The network combines strong omics expertise with expert field/application scientists (food/nutrition sciences, plant protection/plant growth, animal husbandry, apiculture and 10 other fields). Human resources involve more than 60 staff scientists and more than 30 recruits. State-of-the-art technologies and instrumentation is available for the comprehensive mapping of the food composition and available genetic resources, the assessment of the distinct value of foods, and the effect of nutritional intervention on the metabolic profile of biological samples of consumers and animal models. The consortium has the know-how and expertise that covers the breadth of the Greek agri-food sector. Metabolomics teams have developed and implemented a variety of methods for profiling and quantitative analysis. The implementation plan includes the following research axes: development of a detailed database of Greek food constituents; exploitation of "omics" technologies to assess domestic agricultural biodiversity aiding authenticity-traceability control/certification of geographical/genetic origin; highlighting unique characteristics of Greek products with an emphasis on quality, sustainability and food safety; assessment of diet's effect on health and well-being; creating added value from agri-food waste. FoodOmicsGR_RI develops new tools to evaluate the nutritional value of Greek foods, study the role of traditional foods and Greek functional foods in the prevention of chronic diseases and support health claims of Greek traditional products. FoodOmicsGR_RI provides access to state-of-the-art facilities, unique, well-characterised sample sets, obtained from precision/experimental farming/breeding (milk, honey, meat, olive oil and so forth) along with more than 20 complementary scientific disciplines. FoodOmicsGR_RI is open for collaboration with national and international stakeholders.

9.
Food Chem ; 338: 127936, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32932081

RESUMO

The trace and rare earth elements content of 93 honeys of different botanical type and origin have been studied through ICP-MS. Discriminant Analysis (DA) was successful for botanical type and geographical origin classification while Cluster Analysis (CA) was successful only for botanical type. Through Probabilistic Neural Network (PNN) analysis, 85.3% were correctly classified by the network according to their geographical origin and 73.3% according to their organic characterization. A Partial Least Squares (PLS) model was constructed, giving a prediction accuracy of more than 95%. Information obtained using Rare Earths (Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) and trace elements (Li, Mg, Mn, Ni, Co, Cu, Sr, Ba, Pb) via chemometric evaluation facilitated classification of honey samples.


Assuntos
Quimioinformática , Geografia , Mel/análise , Metabolômica , Análise por Conglomerados , Análise Discriminante , Fraude/prevenção & controle , Análise dos Mínimos Quadrados , Metais Terras Raras/análise , Redes Neurais de Computação , Análise Espectral , Oligoelementos/análise
10.
RSC Adv ; 11(19): 11273-11294, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35423655

RESUMO

Honey is a high-value, globally consumed, food product featuring a high market price strictly related to its origin. Moreover, honey origin has to be clearly stated on the label, and quality schemes are prescribed based on its geographical and botanical origin. Therefore, to enhance food quality, it is of utmost importance to develop analytical methods able to accurately and precisely discriminate honey origin. In this study, an all-time scientometric evaluation of the field is provided for the first time using a structured keyword on the Scopus database. The bibliometric analysis pinpoints that the botanical origin discrimination was the most studied authenticity issue, and chromatographic methods were the most frequently used for its assessment. Based on these results, we comprehensively reviewed analytical techniques that have been used in honey authenticity studies. Analytical breakthroughs and bottlenecks on methodologies to assess honey quality parameters using separation, bioanalytical, spectroscopic, elemental and isotopic techniques are presented. Emphasis is given to authenticity markers, and the necessity to apply chemometric tools to reveal them. Altogether, honey authenticity is an ever-growing field, and more advances are expected that will further secure honey quality.

11.
Molecules ; 25(9)2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32392710

RESUMO

Few data exist about the effect of substrates' elemental content on the respective concentrations in cultivated mushrooms, on the degradation of lignocellulosics or on production parameters. Sixteen elements (14 metals and 2 metalloids) were measured by inductively coupled plasma mass spectrometry (ICP-MS) in Pleurotus ostreatus and Cyclocybe cylindracea mushrooms, and in their seven cultivation substrates composed of various plant-based residues. Results revealed a high variability in elemental concentration among substrates which generally led to significant differences in the respective mushroom contents. High bioconcentration factors (BCFs) were noted for Cd, Cu, Mg and Zn for both species in all substrates. BCF of each element was variously affected by substrates' pH, crude composition, and P and K content. Significant positive correlations were demonstrated for Cu, Fe, Mn and Li concentrations vs. a decrease of cellulose and hemicellulose in P. ostreatus substrates, and vs. mushrooms' biological efficiency. In the case of C. cylindracea, Be, Mg and Mn concentrations were positively correlated with the decrease of hemicellulose in substrates, while a significant positive correlation was also recorded vs. mushroom productivity. Finally, it was found that 15% to 35% of the daily dietary needs in Mg, Se and Zn could be covered by mushroom consumption.


Assuntos
Agaricales/química , Lignina/análise , Metais/análise , Pleurotus/química , Solo/química , Oligoelementos/análise , Cádmio/análise , Cobre/análise , Dieta/efeitos adversos , Concentração de Íons de Hidrogênio , Magnésio/análise , Espectrometria de Massas , Fósforo/análise , Potássio/análise , Análise de Componente Principal , Fatores de Risco , Sódio/análise , Oligoelementos/química , Zinco/análise
12.
Antioxidants (Basel) ; 8(9)2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31480630

RESUMO

The basic principles of elemental metabolomics were applied to investigate whether alteration of egg metallome could be achieved after two flavonoids addition, namely hesperidin and naringin in diets of laying hens. A total of 72 hens were divided into six groups: Control (C) (basal diet), E1 (750 mg hesperidin/kg diet), E2 (1500 mg hesperidin/kg diet), N1 (750 mg naringin/kg diet), N2 (1500 mg naringin/kg diet), and VE (200 mg vitamin E/kg diet). The same diet was provided to birds of all treatments, with the exception of added supplements. The diets had the same vitamin and mineral premix; thus, all birds received the same number of elements because no differences on feed intake existed. The egg elemental profile consisted of As, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sb, Se, Sr, V, Zn, and was determined using ICP-MS. Flavonoid supplementation altered the elemental profile. Most notably, in both albumen and yolk, hesperidin increased Ni, Pb, and Sr concentration while it decreased that of Co and Sb. Naringin increased Cd, Cr, Cu, Ni, and V and lowered the concentration of Co and Sb in both yolk and albumen. Vitamin E supplementation, in comparison to the control, decreased Co in both albumen and yolk and also raised Sb in albumen. Flavonoid presence led to the differences in deposition of certain trace minerals in egg compared to that of hens fed a basal diet or a diet with vitamin E supplementation.

13.
Molecules ; 24(4)2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30769769

RESUMO

This study presents the comprehensive elemental profile of Greek Graviera (Gruyère) cheeses. In total, 105 samples from nine different geographic regions produced from sheep, goat and cow milk and their mixtures were assessed. Elemental signatures of 61 elements were investigated for determination of geographic origin and milk type. Regional and milk type classification through Linear Discriminant Analysis was successful for almost all cases, while a less optimistic cross validation exercise presented lower classification rates. That points to further research using a much larger sample set, increasing confidence for cheese authentication utilizing also bioinformatics tools under development. This is the first study reporting signatures of 61 elements in dairy products including all sixteen rare earth elements and all seven precious metals. Safety and quality were assessed regarding toxic and nutritive elements. According to both EU and USA regulations and directives, Graviera is a nutritional source for trace and macro elements with low levels of toxic elements.


Assuntos
Queijo/análise , Microbiologia de Alimentos , Metabolômica , Animais , Bovinos , Queijo/microbiologia , Laticínios/análise , Feminino , Inocuidade dos Alimentos , Cabras , Grécia , Humanos , Leite/química , Leite/metabolismo , Avaliação Nutricional , Ovinos
14.
BMC Med Res Methodol ; 19(1): 37, 2019 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-30786873

RESUMO

BACKGROUND: The aim of the Hellenic National Nutrition and Health Survey was to assess nutritional intake, health status and various behaviors in a representative sample of the Greek population. METHODS: Data collection took place from 01.09.2013 to 31.05.2015. Random stratified sampling was performed by (a) geographical density criteria of Greece (7 regions), (b) age group of the reference population (< 19, 20-64 and > 65 years) and (c) gender distribution. The final population enrolled included (throughout Greece), 4574 individuals (42.5% men; 57.5% women of who 47.2% were from Athens metropolitan area, 18.5% from Central Macedonia, and the remaining 34% almost equally scattered throughout the country (p for the comparisons with official statistics by region, age group and sex > 0.7). Questionnaires developed were based on extensive review of the literature, following a validation procedure when necessary. RESULTS: Preliminary analyses revealed that 32% of the adult population were overweight and 15.5% were obese, with significant gender differences in total and per age group (p < 0.001, for all). The majority of the adult population reported being active smokers (50.4%) or regular alcohol consumers (72.4%); with significant gender differences (p < 0.001, for all). Prevalence of hyperlipidemia was 16.7%, cardiovascular disease 13.9%, hypertension 13.3%, thyroid disease 13.8%, and Diabetes Mellitus 3.6%. Significant gender and age group differences were found in various diseases. CONCLUSIONS: Study's preliminary results provide valuable information about the Hellenic population's health. Findings from this survey could be used to detect disease risk factors for public health prevention policies and programs.


Assuntos
Nível de Saúde , Inquéritos Epidemiológicos/métodos , Inquéritos Nutricionais/métodos , Estado Nutricional , Adolescente , Adulto , Idoso , Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus/epidemiologia , Feminino , Grécia/epidemiologia , Inquéritos Epidemiológicos/estatística & dados numéricos , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais/estatística & dados numéricos , Obesidade/epidemiologia , Prevalência , Fatores de Risco , Adulto Jovem
15.
J Sci Food Agric ; 98(14): 5418-5427, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29675903

RESUMO

BACKGROUND: Concentrations of 16 rare earth elements (REEs) and two actinides were determined for the first time both in cultivated mushrooms and in their production substrates by inductively coupled plasma mass spectroscopy. Moreover, the effect of REEs on cultivation parameters and composition of the final product was assessed, together with their potential use for authentication purposes. RESULTS: The concentrations of REEs varied greatly among seven cultivation substrates and correlated with measurements in Cyclocybe cylindracea mushrooms; no such correlation was established in Pleurotus ostreatus. Reduction of hemicellulose, cellulose, and lignin in substrates during P. ostreatus cultivation was positively correlated with REE concentrations, which also affected the production performance depending on the species examined. In all cases, a negative correlation was established between bioconcentration factors (BCF) in mushrooms and REE content in substrates, while the effect of substrate composition on BCF values varied according to the element studied. The estimated daily intake values of REEs through mushroom consumption was at much lower levels than those reported as potentially harmful for human health. CONCLUSION: The content of REEs in cultivation substrates and in mushrooms revealed that the bioaccumulation of elements differed in each fungus. The nature/origin of substrates seemed to affect the concentration of REEs in mushrooms to a considerable extent. © 2018 Society of Chemical Industry.


Assuntos
Agaricales/crescimento & desenvolvimento , Meios de Cultura/química , Metais Terras Raras/metabolismo , Pleurotus/crescimento & desenvolvimento , Agaricales/química , Agaricales/metabolismo , Meios de Cultura/metabolismo , Carpóforos/química , Carpóforos/crescimento & desenvolvimento , Carpóforos/metabolismo , Metais Terras Raras/análise , Pleurotus/química , Pleurotus/metabolismo
16.
Brief Bioinform ; 19(3): 524-536, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28077402

RESUMO

Elemental metabolomics is quantification and characterization of total concentration of chemical elements in biological samples and monitoring of their changes. Recent advances in inductively coupled plasma mass spectrometry have enabled simultaneous measurement of concentrations of > 70 elements in biological samples. In living organisms, elements interact and compete with each other for absorption and molecular interactions. They also interact with proteins and nucleotide sequences. These interactions modulate enzymatic activities and are critical for many molecular and cellular functions. Testing for concentration of > 40 elements in blood, other bodily fluids and tissues is now in routine use in advanced medical laboratories. In this article, we define the basic concepts of elemental metabolomics, summarize standards and workflows, and propose minimum information for reporting the results of an elemental metabolomics experiment. Major statistical and informatics tools for elemental metabolomics are reviewed, and examples of applications are discussed. Elemental metabolomics is emerging as an important new technology with applications in medical diagnostics, nutrition, agriculture, food science, environmental science and multiplicity of other areas.


Assuntos
Elementos Químicos , Análise de Alimentos/métodos , Espectrometria de Massas/métodos , Metabolômica , Proteínas/análise , Tecnologia de Alimentos , Humanos
17.
Appl Spectrosc ; 72(3): 432-441, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29199851

RESUMO

Synchronous fluorescence spectroscopy (SFS) is used for quantitative analysis as well as for qualitative analysis, such as with classification methods. With SFS, determination of a useful wavelength interval between the excitation and emission wavelengths (Δλ) is required. There are a multitude of Δλ intervals that can be evaluated and optimization of the best one is complex. Presented here is a fusion approach for combining Δλ intervals, thereby negating the need to perform the selection by a skilled operator. To demonstrate the feasibility of omitting selection of the best Δλ interval, adulterated argan oil samples are studied. Argan oil is made from the argan tree, endemic to southwestern Morocco, and is well-known for its cosmetic, pharmaceutical, and nutritional applications. It is considered a luxury product and exported from Morocco around the world. Consequently, detection of argan oil adulteration followed by quantitative analysis of the adulterant concentration is important. This study uses fusion of SFS spectra obtained at ten Δλ intervals to first detect adulteration of argan oil by corn oil and then determination of the corn oil content. For detection of adulteration, 15 one-class classification methods were used simultaneously over the ten Δλ sets of SFS spectra. For tuning parameter dependent classifiers such as Mahalanobis distance, non-optimized classifiers are used. Raw classification values are used, removing the need to set classifier-dependent threshold values, albeit, ultimately, a fusion decision rule is needed for classification. For quantitative analysis, two calibration approaches are evaluated with fusion of these ten Δλ SFS spectral data sets. One is multivariate calibration by partial least squares (PLS). The second approach is a univariate calibration process where the SFS spectra are summed over respective SFS spectral ranges, also known as the area under the curve (AUC). For adulteration detection and quantitation of the corn oil, prediction errors decrease with fusion compared to individually using the ten Δλ interval SFS specific data sets. For this argan oil data set, the AUC method generally provides equivalent prediction errors to PLS.

18.
Food Chem ; 213: 238-245, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27451177

RESUMO

This study examines the trace and rare earth elemental (REE) fingerprint variations of PDO (Protected Designation of Origin) "Fava Santorinis" over three consecutive harvesting years (2011-2013). Classification of samples in harvesting years was studied by performing discriminant analysis (DA), k nearest neighbours (κ-NN), partial least squares (PLS) analysis and probabilistic neural networks (PNN) using rare earth elements and trace metals determined using ICP-MS. DA performed better than κ-NN, producing 100% discrimination using trace elements and 79% using REEs. PLS was found to be superior to PNN, achieving 99% and 90% classification for trace and REEs, respectively, while PNN achieved 96% and 71% classification for trace and REEs, respectively. The information obtained using REEs did not enhance classification, indicating that REEs vary minimally per harvesting year, providing robust geographical origin discrimination. The results show that seasonal patterns can occur in the elemental composition of "Fava Santorinis", probably reflecting seasonality of climate.


Assuntos
Análise de Alimentos , Metais Terras Raras/análise , Oligoelementos/análise , Vicia faba/química , Clima , Análise Discriminante , Geografia , Análise dos Mínimos Quadrados , Limite de Detecção , Análise Multivariada , Redes Neurais de Computação , Análise de Componente Principal , Reprodutibilidade dos Testes , Estações do Ano
19.
Bioresour Technol ; 214: 504-513, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27176670

RESUMO

Spent sulphite liquor (SSL) has been used for the production of lignosulphonates (LS), antioxidants and bio-based succinic acid. Solvent extraction of SSL with isopropanol led to the separation of approximately 80% of the total LS content, whereas the fermentations carried out using the pretreated SSL with isopropanol led to the production of around 19g/L of succinic acid by both Actinobacillus succinogenes and Basfia succiniciproducens. Fractionation of SSL via nanofiltration to separate the LS and solvent extraction using ethyl acetate to separate the phenolic compounds produced a detoxified sugar-rich stream that led to the production of 39g/L of succinic acid by B. succiniciproducens. This fractionation scheme resulted also in the production of 32.4g LS and 1.15g phenolic-rich extract per 100g of SSL. Both pretreatment schemes removed significant quantities of metals and heavy metals. This novel biorefinery concept could be integrated in acidic sulphite pulping mills.


Assuntos
Antioxidantes/análise , Biotecnologia/métodos , Fracionamento Químico/métodos , Lignina/análogos & derivados , Ácido Succínico/análise , Sulfitos/química , Ácidos Sulfônicos/análise , Eliminação de Resíduos Líquidos , 2-Propanol/química , Acetatos/química , Actinobacillus/metabolismo , Carboidratos/análise , Fermentação , Filtração , Lignina/análise , Nanotecnologia , Solventes
20.
Food Chem ; 204: 513-520, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26988531

RESUMO

A novel method for automated determination pectin degree of esterification (DE) using micro sequential injection lab-on-valve (µSI-LOV) system is developed. A face-centered central composite response surface methodology (RSM) was used to optimise system parameters. A calibration graph for determination of non-esterified galacturonic acid (GalA) content in pectin solutions with linear range of 0.08-0.34% (w/v) and the limit of detection (LOD) of 0.057% (w/v) under optimal condition was achieved. The difference between concentrations (w/v, %) of total GalA and non-esterified GalA was applied to estimate DE (%) of pectin samples. Results indicated a good agreement (tstat

Assuntos
Técnicas de Química Analítica/métodos , Química Verde , Pectinas/química , Técnicas de Química Analítica/instrumentação , Esterificação , Química Verde/instrumentação , Limite de Detecção
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