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The article presents the luminance results of printouts for eight fluorescent inks intended for various applications, e.g., securing documents and packages, safety signs, or decorative effects. The research involves inks with 30% pigment concentration. The novelty is to show the luminescence depending on the ink film thickness and colour properties. The range of printout ink layer thicknesses is from 0 to 100 μm. The article presents scanning electron images and energy dispersive analysis of tested pigments, spectrofluorometric measures of lifetime, quantum yield, and Stokes shift. It also shows the rheological properties of pigment powder and inks and the optical properties, i.e., colour parameters, transparency, gloss, luminescence intensity, and the fluorescence expressed by the ΔCh, Δb∗, and ΔL∗ parameters. The surface topography and morphology, grain size, pigment shoreline, and roughness of the particles influence the fluorescent effect. The elemental composition, the b∗ colour parameter value in the CIELAB space, and lightness also affect the fluorescence. Pigments with a small grain and a smoother surface, such as chrome, orange, and yellow, shine much better than those with a more significant pigment grain and a rougher structure, such as violet and blue. The topography of pigments also affects their rheological properties and ink rheology. An increase in the ink layer thickness resulted in a decrease in its gloss and transparency values. However, the gloss and transparency do not affect the level of fluorescence, which increases with the ink film thickness to a certain maximum specified for a given ink colour. The equations in the article enable the fluorescent ink users to predict and adjust the appropriate thickness of its layer to obtain desired glowing effects. [Display omitted] • Ink rheology, surface tension, pigment topography roughness on ink luminance. • Gloss and transparency dependence on ink film thickness and pigment content. • Energy dispersive elemental and SEM analysis of fluorescent pigments. • Describing the mathematical models on ink film thickness and fluorescence. • Discovering the optimal fluorescent film thickness to obtain the maximum glow. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the quality parameters and the oxidative stability (180 days of storage) of a water–oil emulsion formulated with Calabrian (Italy) monovarietal Agristigna extra virgin olive oil and apple vinegar. The best extra virgin olive oil/apple vinegar ratio was found to be 85/15 (v/v) and lecithin (2% w/v) was the best additive to reach proper stability and viscosity over time. An increase of lightness parameters was evidenced in both products in a storage time-dependent manner. During storage, both oil and dressing showed a free acidity level beyond the accepted limit for extra virgin olive oil, whereas a slight increase of the peroxide value was observed only for Glasoil at the end of the observation time without affecting sensory attributes. A general decrease of phytochemicals was observed for extra virgin olive oil and Glasoil, with different reduction trends and degrees depending on the chemical class. A lower stability of Glasoil during shelf-life was confirmed by the worsening of the rheological features and by the polyunsaturated fatty acids reduction (up to −21.71%) with a corresponding increase of the monounsaturated fatty acids/polyunsaturated fatty acids ratio (about +25.69%). [ABSTRACT FROM AUTHOR]

This study aimed to investigate the quality parameters and the oxidative stability (180 days of storage) of a water–oil emulsion formulated with Calabrian (Italy) monovarietal Agristigna extra virgin olive oil and apple vinegar. The best extra virgin olive oil/apple vinegar ratio was found to be 85/15 (v/v) and lecithin (2% w/v) was the best additive to reach proper stability and viscosity over time. An increase of lightness parameters was evidenced in both products in a storage time-dependent manner. During storage, both oil and dressing showed a free acidity level beyond the accepted limit for extra virgin olive oil, whereas a slight increase of the peroxide value was observed only for Glasoil at the end of the observation time without affecting sensory attributes. A general decrease of phytochemicals was observed for extra virgin olive oil and Glasoil, with different reduction trends and degrees depending on the chemical class. A lower stability of Glasoil during shelf-life was confirmed by the worsening of the rheological features and by the polyunsaturated fatty acids reduction (up to −21.71%) with a corresponding increase of the monounsaturated fatty acids/polyunsaturated fatty acids ratio (about +25.69%).

Feteasca Neagra is a Romanian black grape variety, which is vinified in various styles, but seems to evolve better when maturated in oak barrels. To rapidly assess the evolution of this variety in the presence of wood, an experiment was designed to account for the contact with wood, as well as the presence of lower or medium oxygen levels. Oak chips of different origins (American and French) were used, each with a medium and high degree of toasting, respectively. Freshly obtained wines were kept in contact with 3 g/l of these oak chip samples for 2 months, either protected from air or in conditions simulating the oxygenation level obtained during barrel maturation. The colour of the samples was assessed spectrophotometrically after 2, 4, 6 and 8 weeks of wood contact. Sensory analysis of wines was also performed after 2 months of wood contact. After this short experimental period it was observed that oxygen is correlated with a reduced clarity and is inducing a more yellow hue in the wines, irrespective of the time of assessment. Furthermore, chips are changing the initial colour of wines bringing some yellow hues of their own, especially in the case of medium-toasted oak chips, but in time this effect fades away. The intensity of colour is, however, increased by the highly-toasted chips, the effect being also reduced by oxidative maturation. The sensory analysis showed that the overall quality of the control sample is the most affected by the presence of oxygen, while the aftertaste also scored lower than in the case of wines produced with chips contact. During this short time of experimentation the toasting degree of the chips did not significantly influence the colour parameters and sensory scores, but the origin of the chips is starting to show a sensory influence when wines maturate, proven by a slight increase in the sensory scores for samples treated with American chips in the presence of moderate oxygenation level. Considering these findings it seems that Feteasca Neagra would indeed benefit from wood contact, especially with oak of American origin. The abstract is too long (maximum 180 words or 10 rows) [ABSTRACT FROM AUTHOR]

Since ancient times, vegetables have been preserved in oil, to be consumed throughout the year, and not just during the period in which they were harvested. Dried tomato slices in Extra Virgin Olive Oil (EVOO) are one of the most famous Italian preserves. This is the first study which aimed to investigate the shelf-life parameters of this preserve during the 12 months of storage in both light and dark conditions. For this purpose, quality and CIELab color parameters were analysed in EVOO alone and as preserving liquid; total phenols and carotenoids content as well as β-carotene and lycopene content, a fatty acids profile, and antioxidant activities were examined. Results showed that samples stored in the dark are protected against degradative processes. Moreover, after 6 months of storage, the EVOO used as preserving liquid is enriched by the phytochemicals contained in dried tomato slices. This enrichment of EVOO by tomato bioactive compounds is reflected in the increase in the antioxidant activity of the oil independently by the presence of light during storage.

A comprehensive data collection of authentic “specialty” or “gourmet” oils, namely cold-pressed industrial virgin oils, was performed. Eight different botanical species, i.e., Almond, Apricot, Avocado, Hazelnut, Mosqueta rose, Rosehip, Sunflower, and Walnut oils were studied plus Olive oil as the gold standard of cold-pressed virgin oils. Two different analytical approaches are proposed to rapidly verify the botanical species of the oil-based raw material. The first approach is based on a multivariate statistical analysis of conventional analytical data, namely their fatty acid composition. These data have been re-elaborated in a multivariate way by Principal Component Analysis (PCA) and classification methods. The second approach proposes a fast and non-destructive spectrophotometric analysis to determine the color of these oils to discriminate among different species. In this regard, the raw diffuse reflectance spectra (380–780 nm) obtained by a UV-Vis spectrophotometer with an integrating sphere was considered and elaborated by chemometrics. This information was compared with the results obtained by the most common approach based on the CIELab parameters. A data fusion of chromatographic and spectral data was also investigated. Either fatty acid composition or color of these oils demonstrated to be two promising markers of their botanical authenticity.

• Tertiary colours were introduced to white cement pastes using a digital colouration approach. • Design of Experiments (DoE) was used to quantify the relationship of pigment attributes with colour parameters in CIELAB space. • Eight series of quadratic polynomial models were set up to correlate the L * a * b * values of coloured cement pastes with the pigment types and additions. • Cement-based materials in tertiary colours can be widely applied to various scenarios. A tertiary colour design methodology based on the design of experiments (DoE) is introduced for cement paste in this paper. Different types and dosages of pigments are mixed into white cement to form tertiary colours. The quantitative correlation between the types and dosages of iron oxide pigments and the CIELAB parameters for coloured cement paste is established. The experimental results show that for the given ranges of pigment dosage: 0 ∼ 5% for white, red, yellow, blue, and green pigments and 0 ∼ 3.5% for black pigment, not just the white pigment but the black pigment also plays an important role in affecting the variations in the CIELAB parameters. The additions of red, yellow, green and blue pigments influence the green–red and blue-yellow opponent colours, and an interaction at high levels of addition for a pair of pigments is recognized. With the help of DoE, eight series of quadratic polynomial models were set up to correlate the CIELAB parameters obtained for coloured cement pastes with the pigment attributes. By using this method, tertiary colours can be introduced to cement-based materials that can satisfy the needs of various application scenarios. [ABSTRACT FROM AUTHOR]

Abstract: Colour is one of the major attributes that affect the consumer perception of food quality. Several pigments in foods, measurable by colourimetric instrumentation, possess biological activity. The present work is a review of studies that assessed the colour changes (by the CIELAB parameters) and the bioactive compound content, analysing statistically their correlation in a broad spectrum of foods. An emphasis was placed on the contribution of phenolics, carotenoids, chlorophylls and betalains on the food colour characteristics during different processing and storage conditions. The correlation between these compounds and the colour changes of some foods had r-values higher than 0.72, according to the Pearson correlation analysis. This suggests that colour instrumentation may be an efficient and practical technique to indirectly estimate the presence of bioactive components. This approach potentially facilitates the real-time quality control of biological compounds during the food industry processes. [Copyright &y& Elsevier]

Abstract: The effect of UV–visible light irradiation on the changes in color and chemical composition of the surfaces of Abies alba L. (fir, a softwood), non-modified and chemically modified, was studied. Chemical modification of the wood was performed by reaction with succinic anhydride in xylene at different concentration values. The wood samples were irradiated in air using a rotative device equipped with a middle pressure mercury lamp. Analysis of the color changes in wood surfaces during photo-degradation was carried out by measuring CIELAB parameters. Fourier transform infrared spectroscopy was used to study chemical changes caused by light irradiation. Irradiation modified physical and chemical characteristics of wood surfaces and resulted in rapid color changes, degradation of lignin and increased content of chromophoric groups on the wood surfaces. Color changes (ΔEab ) correlate well with degradation of lignin. [Copyright &y& Elsevier]

A supercritical solvent impregnation (SSI) technique was employed to incorporate, by batch- and semicontinuous-modes, bioactive olive leaf extract (OLE) into a food-grade multilayer polyethylene terephthalate/polypropylene (PET/PP) film for active food packaging applications. The inclusion of OLE in the polymer surfaces significantly modified the colour properties of the film. A correlation of 87.06% between the CIELAB colour parameters and the amount of the OLE impregnated in the film was obtained which suggests that colour determination can be used as a rapid, non-destructive technique to estimate the OLE loading in the impregnated matrices. The UV barrier and water permeability properties of the films were not significantly modified by the incorporation of OLE. The migration of OLE into a 50% (v/v) ethanol food simulant demonstrated faster release of OLE from the PP surface than from the PET surface which may be due to the different interactions between OLE and each polymer. [ABSTRACT FROM AUTHOR]

Abstract: Flowers of tulips (17 species and 25 cultivars) were subjected to qualitative and relative quantitative examination for anthocyanins. Altogether five anthocyanins were identified as the 3-O-(6″-O-α-rhamnopyranosyl-β-glucopyranoside) of delphinidin (1), cyanidin (2) and pelargonidin (3), and the 3-O-[6″-O-(2‴-O-acetyl-α-rhamnopyranosyl)-β-glucopyranoside] of cyanidin (4) and pelargonidin (5). The pigments 1–5 represented 7%, 43%, 12%, 2% and 31%, respectively, of the total anthocyanin amount in the tepals of the Tulipa species, and 20%, 37%, 30%, 6% and 4%, respectively, in the cultivar tepals. Nearly 50% of the samples contained acetylated anthocyanins. The colours of the freeze-dried tepals described by the CIELab coordinates, hue angle (h ab), saturation (C*), and lightness (L*) together with the anthocyanin content were subjected to multivariate analysis. All tepals classified with hue angles described as “blue nuances” were from cultivars. They contained 1 as the major anthocyanin, and no or just traces of pelargonidin derivatives. The species and cultivars having “magenta nuances” showed similar anthocyanin content with increased relative proportions of 2 at the expense of 1. Orange coloured tepals were to a large extent correlated with high relative proportions of the pelargonidin derivatives, 3 and 5. Acetylation of anthocyanins furnished a weak colour effect opposite to the bluing effect previously reported for anthocyanins with aromatic acyl groups. All six species belonging to the section Eichleres (subgenus Tulipa) were after principal component analysis grouped closely together. They were characterized by high concentrations of the pelargonidin derivatives 3 and 5, and orange petal nuances. However, within section Tulipa (subgenus Tulipa), considerable anthocyanin variation was observed. Species in the subgenus Eriostemones were generally characterized by the two anthocyanins 1 and 2, and no pelargonidin derivatives. [Copyright &y& Elsevier]

Multiple and simple regression analyses were assessed to establish mathematical models that allow the evaluation of CIELAB parameters from absorbance values at 420, 520 and 620 nm. All these variables were measured in 180 commercial red wines, using 130 of them to obtain the mathematical models. The results showed that the CIELAB parameters L*, a* and C* for the CIE D65/10° illuminant/observer conditions can be correctly estimated (with small standard error of estimation) from absorbance values at 520 nm, as an independent variable. However, the parameters h and b* showed higher average errors between the predicted and observed values, but they were correctly estimated using multiple linear regression models with the three absorbances at 420, 520 and 620 nm (b*) or using the ratio of A420 to A520 as independent variable (h). The models obtained could be helpful to wineries that in general, do not have the necessary equipment and software to determine the CIELAB parameters, which are recognized as being the best parameters for defining the colour of wines. [Copyright &y& Elsevier]

A supercritical solvent impregnation (SSI) technique was employed to incorporate, by batch- and semicontinuous-modes, bioactive olive leaf extract (OLE) into a food-grade multilayer polyethylene terephthalate/polypropylene (PET/PP) film for active food packaging applications. The inclusion of OLE in the polymer surfaces significantly modified the colour properties of the film. A correlation of 87.06% between the CIELAB colour parameters and the amount of the OLE impregnated in the film was obtained which suggests that colour determination can be used as a rapid, non-destructive technique to estimate the OLE loading in the impregnated matrices. The UV barrier and water permeability properties of the films were not significantly modified by the incorporation of OLE. The migration of OLE into a 50% ( v / v ) ethanol food simulant demonstrated faster release of OLE from the PP surface than from the PET surface which may be due to the different interactions between OLE and each polymer.

Since ancient times, vegetables have been preserved in oil, to be consumed throughout the year, and not just during the period in which they were harvested. Dried tomato slices in Extra Virgin Olive Oil (EVOO) are one of the most famous Italian preserves. This is the first study which aimed to investigate the shelf-life parameters of this preserve during the 12 months of storage in both light and dark conditions. For this purpose, quality and CIELab color parameters were analysed in EVOO alone and as preserving liquid; total phenols and carotenoids content as well as β-carotene and lycopene content, a fatty acids profile, and antioxidant activities were examined. Results showed that samples stored in the dark are protected against degradative processes. Moreover, after 6 months of storage, the EVOO used as preserving liquid is enriched by the phytochemicals contained in dried tomato slices. This enrichment of EVOO by tomato bioactive compounds is reflected in the increase in the antioxidant activity of the oil independently by the presence of light during storage. [ABSTRACT FROM AUTHOR]

Opal glasses fabricated by Arc (Arques, France) are glass-ceramics that consist of a glassy matrix mainly constituted of silicon dioxide with well crystallized fluoride compounds as inclusions. These later (ca. 8 vol%) play the role of light scattering centers leading to the well-known milky feature of the commercialized glassware, dinnerware products. Their overall chromatic characteristics strongly depend on few parameters (e.g. the refractive indexes of the glass and the ceramic(s), the concentration of inclusions, their mean size, the surface roughness of the article, etc) that have to be determined and controlled during the manufacturing process to end at the product with the desired optical properties. Using a transfer matrix formalism, the 4-flux method can indeed be used to anticipate the transmittance and reflectance of an object for different set of parameters. The impact of each aforementioned parameter on the color rendering will be here separately discussed, and simulations will be confronted to experimental data to assert their validity and their interest to the genesis of new products with targeted optical properties. [ABSTRACT FROM AUTHOR]

A comprehensive data collection of authentic "specialty" or "gourmet" oils, namely cold-pressed industrial virgin oils, was performed. Eight different botanical species, i.e., Almond, Apricot, Avocado, Hazelnut, Mosqueta rose, Rosehip, Sunflower, and Walnut oils were studied plus Olive oil as the gold standard of cold-pressed virgin oils. Two different analytical approaches are proposed to rapidly verify the botanical species of the oil-based raw material. The first approach is based on a multivariate statistical analysis of conventional analytical data, namely their fatty acid composition. These data have been re-elaborated in a multivariate way by Principal Component Analysis (PCA) and classification methods. The second approach proposes a fast and non-destructive spectrophotometric analysis to determine the color of these oils to discriminate among different species. In this regard, the raw diffuse reflectance spectra (380–780 nm) obtained by a UV-Vis spectrophotometer with an integrating sphere was considered and elaborated by chemometrics. This information was compared with the results obtained by the most common approach based on the CIELab parameters. A data fusion of chromatographic and spectral data was also investigated. Either fatty acid composition or color of these oils demonstrated to be two promising markers of their botanical authenticity. [ABSTRACT FROM AUTHOR]

Argan oil (AO) has traditionally been used for its dermatologic and hepatoprotective effects and for human nutrition. Traditionally, AO extraction is carried out by Moroccan women with the help of stone mill pressing. However, it is long and slow process that frequently is achieved at deficit hygiene conditions. In this research, unroasted seeds (US) and roasted seeds (RS) of argan tree have been extracted using different extraction systems: n -hexane, n -hexane:acetone (1:1, v/v), ethyl acetate, acetone, ethanol:water (96:4, v/v), and water. The main results are; Hexane: acetone extraction yielded the highest FA amounts, at 39.7 g FA/100 g of total US seed, followed by acetone (36.5 g FA/100 g US seed). The main FA in all extracts were oleic acid, from 52.1 (ethanol:water) to 57.7% (hexane), and linoleic acid from 22.9 (hexane, US) to 29.3% (ethanol:water, RS), both of total FA. Oxidation levels, computed by conjugated diene index (CD), was extremely low for all extraction processes. CD were higher in RS in comparison with US, due to compounds produced in Maillard reactions. Colour parameters indicated a color variation from yellow (US) to brown (RS). Therefore, the conclusions can be summarized as follows. All extracting systems yielded good quality argan oil, thus, the tested procedures constitute a suitable alternative to the traditional extraction processes. The obtained oils could be used in the alimentary and cosmetic industries with different applications. Future research should be directed to check the unsaponifiable fractions of the oils here obtained. Overall, this research opens new perspectives for industries focused on argan oil extraction. Image 1 • Roasted and unroasted argan seeds were extracted using various-polarity solvents. • Clean extraction by ethyl acetate was similar to that achieved by hexane or acetone. • Oleic acid and linolenic acids were the main fatty acids in all extracts. • Conjugated dienes index indicated low alteration levels for all extraction systems. • Oil color varies from yellow (unroasted) to brown (roasted) seeds. [ABSTRACT FROM AUTHOR]