Search

Red pitaya peels (RPP), often discarded as waste, are rich in betacyanin, making them a potential natural colourant for food products such as gummy candy. However, citric acid may influence the quality and stability of the colourant. This study examined the physicochemical, antioxidant, and sensory properties of RPP gummy candies with different citric acid concentrations. The RPP were dehydrated, ground into powder, and incorporated into gummy formulations. Citric acid significantly reduced water activity (p<0.05), lowered pH, and increased titratable acidity. Colour analysis showed a significant rise (p<0.05) in a* value with higher citric acid, indicating a redder colour. Samples containing 3% citric acid exhibited a marked reduction (p<0.05) in chewiness. Antioxidant properties were also affected, with the 3% citric acid sample showing the highest total phenolic content (0.91 mg GAE/g) and DPPH radical scavenging activity (40.73%). However, total betacyanin content declined significantly (p<0.05) in samples with citric acid, ranging from 0.55-0.85 mg/g, compared to 1.79 mg/g with 0% citric acid. Sensory evaluation revealed that the sample F2 with 1% citric acid sample received the highest scores for most attributes, suggesting an optimal balance between flavour and texture. Overall, the study highlights the potential of RPP as a natural colourant and demonstrates how varying citric acid concentrations impact the physical, antioxidant, and sensory qualities of gummy candy. These findings underscore the importance of optimising citric acid levels to maintain both the functional and sensory attributes of RPP-infused gummy candies. [ABSTRACT FROM AUTHOR]

Incorporating natural colourants in sausage production offers an avenue to enhance product desirability while meeting consumer preferences for clean-label ingredients. This paper thoroughly examines the selection, formulation, processing, and quality control aspects involved in utilizing natural colourants in sausages, with particular attention to beetroot. Key subjects explored encompass a variety of natural colourant sources and types, diverse extraction techniques, factors influencing colour stability, regulatory considerations, and consumer perception. Furthermore, the paper delves into emerging trends and advancements in sausage manufacturing, such as plant-based alternatives, functional fortification, and sustainability initiatives. By strategically harnessing the potential of natural colourants, including beetroot, sausage producers can customize their offerings to align with consumer preferences, distinguish their products, and bolster their competitiveness in the market.

Incorporating natural colourants in sausage production offers an avenue to enhance product desirability while meeting consumer preferences for clean-label ingredients. This paper thoroughly examines the selection, formulation, processing, and quality control aspects involved in utilizing natural colourants in sausages, with particular attention to beetroot. Key subjects explored encompass a variety of natural colourant sources and types, diverse extraction techniques, factors influencing colour stability, regulatory considerations, and consumer perception. Furthermore, the paper delves into emerging trends and advancements in sausage manufacturing, such as plant-based alternatives, functional fortification, and sustainability initiatives. By strategically harnessing the potential of natural colourants, including beetroot, sausage producers can customize their offerings to align with consumer preferences, distinguish their products, and bolster their competitiveness in the market. [ABSTRACT FROM AUTHOR]

Edible flowers are rich in bioactive compounds and pigments that are on increasing demand in nutraceutical, medicinal, food, cosmetic and dyeing industries. This study evaluated the anthocyanins, phenolics and antioxidant activity of eight edible flowers (Bellis perennis L., Centaurea cyanus L., Dianthus carthusianorum L., Lavandula angustifolia Mill., Primula vulgaris Huds., Rosa canina L., Rosa pendulina L. and Viola odorata L.) after 24 h of hot drying (50 °C; natural convection stove) or cold drying (CD) (22 °C; heat-pump drying system). The hot-dried and cold-dried materials were then used to prepare ultrasound-assisted extracts, which are used as food additives or as a source of natural colourants, or decoctions (DECs), which are used for herbal teas. The edible flower UAEs and DECs had high amounts of anthocyanins (up to 3,284.6 mg C3G · 100 g-1), phenolics (up to 9,034 mg · 100 g-1) and antioxidant activity (866 μmol TE · g-1, 4,901 mmol Fe2+ · kg-1), with roses having the highest amount. The anthocyanin content and phenolic profile (flavonols, benzoic acids, cinnamic acids and flavanols) of edible flowers are found to be affected by drying and extraction methods. For decoctions, CD was found to be the most efficient drying method for all the parameters. For UAEs, CD resulted in a higher anthocyanin content, while hot drying resulted in a higher phenolic content, particularly flavanols. Overall, the studied edible flower extracts and decoctions can contribute to healthy and coloured substances, which can be used for designing innovative natural products. Rosa pendulina and R. canina are the most promising sources.

This study aimed to obtain an anthocyanin extract from the purple leaves of Camellia sinensis cv. Zijuan using a sustainable, non-toxic, and low-cost solid-liquid extraction, employing an aqueous citric acid solution (0.2 mol/L) as the extracting solvent, and to evaluate its chemical stability at different pH values, as well as its in vitro antioxidant properties in chemical and biological terms. The phenolic composition, in vitro antioxidant activity, and the stability of anthocyanins against pH, temperature, and light of the crude extract (CE) were evaluated, as well as the phenolic composition and bioactivity in the crude lyophilised extract (CLE). In the direct/reverse spectrophotometric titration, anthocyanins showed structural changes between pH 2 and 10, and reversibility of 80%. The antioxidant activity against the DPPH radical showed inhibition percentages of 73% (pH 4.5) to 39% (pH 10). Thermal stability was observed at 60 °C, and prolonged exposure of the extract to light caused photodegradation of the anthocyanins. Thirty-three phenolic compounds, including anthocyanins and catechins, were quantified in the CLE by UPLC-ESI-MS and HPLC, totalling 40.18 mg/g. CLE reduced cell viability (IC50 from 18.1 to 52.5 μg GAE/mL), exerted antiproliferative (GI50 from 0.0006 to 17.0 μg GAE/mL) and cytotoxic (LC50 from 33.2 to 89.9 μg GAE/mL) effects against A549 (human lung adenocarcinoma epithelial cells), HepG2 (hepatocellular carcinoma), HCT8 (ileocecal colorectal adenocarcinoma), and Eahy926 (somatic cell hybrid cells); and showed protection against oxidation of human plasma (635 ± 30 mg AAE/g). The results showed the diversity of compounds in the extracts and their potential for technological applications; however, temperature, pH, and light must be considered to avoid diminishing their bioactivity.

Natural colourants were widely employed in the ancient world to colour cotton garments. With the revolution of synthetic dyes, natural dyes have lost their position in respect of some performance. However, nowadays the demand for sustainable and eco-friendly products is increasing worldwide due to the awareness of ecological balance. The purpose of this study is to utilize natural colourants in printing on cotton fabric. In this regard, the colourants were extracted from myrobalan fruit, pomegranate peel and catechu, which were eventually applied to the fabric by screen printing technique. The print paste was prepared with carboxymethyl cellulose (CMC) as a natural thickener and polyvinyl alcohol (PVA) as a synthetic thickener. The stability of the print paste was studied with respect to time elapse by viscosity measurement. The depth of shade and colour fastness of the printed fabric were measured. K/S value was evaluated with respect to the stability of print paste. The viscosity was changed slightly in both the CMC and PVA thickener with respect to the stability of the print paste. The washing fastness grades for colour staining wash ranged from 4 to 5, rubbing fastness grades of dry rubbing also ranged from 4 to 5, wet rubbing fastness was 3/4 to 4/5 as well as perspiration fastness grades in alkaline, and in acidic it was 3/4 to 5. Thus, myrobalan fruit, pomegranate peel and catechu have shown excellent performance in printing on cotton textiles, which could be an alternative to the synthetic counterpart.

Cyanobacterial pigments such as chlorophyll, carotenoids and phycobiliproteins are considered as ecofriendly natural colourants used in food and food additives as they have nutraceutical value, non-toxic and non-carcinogenic. The present study focused on extraction, partial characterization of extracellular polysaccharides (EPS), phycocyanin and mycosporin like amino acid (MAA) from a freshwater cyanobacterium Oscillatoria pseudogeminata G.Schmid.The purified isolate of O. pseudogeminatawas deposited and maintained in the NRMC-F, Bharathidasan University. The EPS was extracted with the help of double volume of ice-cold acetone and confirmed by UV (260 and 280 nm), FTIR and XRD analyses. Phycocyanin and MAA were also extracted from O. pseudogeminata biomass using double distilled water. The UV-Vis Spectrophotometric results revealed that 520 and 230 nm peaks represent phycocyanin and MAA, respectively. Further, the process of scaling-up the biomass and increase the productivity of EPS, Phycocyanin and MAA from Oscillatoria pseudogeminata is under raceway pond system, already initialed in our laboratory. [ABSTRACT FROM AUTHOR]

In the present study, an attempt had been made to explore the potential of natural colourants and its application in the textile industry. Natural colorants extracted from the sepals of Mussaenda hybrid, fruits of Carissa carandas and Syzygium cumini were applied on cotton, silk and polyester yarns accompanied with mordants (Alum, Acetic acid, Copper sulphate and Lemon juice) and without mordant, using an aqueous method. UV-Vis spectra of different natural dyes were determined. Percent absorption, colour co-ordinates values (CIELab), colour strength (K/S) values and fastness properties of the selected dyed yarns were tested. Different shades of yellow, pink and purple were obtained from the aqueous extracts of Mussaenda hybrid, Carissa carandas and Syzygium cumini. K/S values were enhanced with the addition of mordants. Fastness results of the selected dyed yarns showed good grades. The present study demonstrated that the above plants could be a promising source of natural colourants. [ABSTRACT FROM AUTHOR]

This work aimed to evaluate the stability of sorghum 3‐deoxyanthocyanins (DXA) in model beverages (pH 3.5) elaborated with crude sorghum phenolic extract, containing ascorbic acid and sulphite, under fluorescent light exposure and subjected to heat treatment. There was no significant difference in the DXA degradation during storage under light exposure (24.16%) and absence of light (20.72%). DXA degradation did not differ in the presence of ascorbic acid during storage under light exposure (23.99–25.38%) and absence of light (19.87–21.74%). The addition of sulphite caused an initial bleaching reaction, but as a reversible reaction, the anthocyanin content was higher on the last day of storage compared to the first day. There were no significant differences in total anthocyanin content of all treatments subjected to the heat treatment (80 °C for 5 and 25 min). Thus, crude DXA are very stable under light, additives and heat, and may be useful as natural food colourants. [ABSTRACT FROM AUTHOR]

The main objective of the presented research was to study the possibility of using natural colourants obtained through the aqueous extraction of fresh leaves from the Junglans regia (J. regia), or common walnut tree, for the dyeing of wool yarn. A unique principle was explored by combining the phases of extraction and mordanting into one with the aim of shortening the dyeing procedure, while at the same time extracting more colouring components. Spectrophotometric studies revealed the signifi cant impact of both mordant addition and dye-bath pH on the absorbance curve and thus on the colour and K/S values of the dyed samples. A meta-ordanting technique using ferrous sulphate produced a greater depth of shade at a wavelength of 400 nm, with respect to the concentration of mordant and the liquid ratio of the extraction. Finally, wool yarn dyed with pure leaf extracts exhibited a potent inhibiting activity against Candida albicans (C. albicans) with a moderate reduction rate of 59%, and an inhibited response against Staphylococcus aureus (S. aureus) with a low reduction rate of 38.6%.

Production of functional foods containing such functional ingredients as pectin and anthocyanins is particularly important nowadays. The goal of the given research was to study the effect of high esterified pectin obtained from apples at a dosage of 0.3% on the changes of viscosity and color of drinks based on cherry juice and anthocyanin colourant obtained from black carrot, apple juice and sugar color IV during storage in a dark place at 22 ± 3 °C for 180 days. Optical density was measured using spectrophotometric method at a wavelength of 350 to 700 nm. Mass fraction of solid matter was adjusted using sucrose to reach 10.1 ± 0.7 %, pH for drinks based on cherry juice and anthocyanin colourant obtained from black carrot was adjusted to reach 3.0, and for drinks based on apple juice and sugar color IV – to reach 3.5 in the prepared beverages. The author shows that pectin does not have any significant effect on colour retention in drinks based on cherry juice and anthocyanin obtained from black carrot, and that anthocyanin colourant from black carrots is more stable during storage than the colourant that cherry juice contains. The color of the drinks based on apple juice and sugar color IV without pectin remains almost the same during storage. In the visible spectrum region they have a monotonous graph of the change in optical density, and pectin makes a significant contribution to the final color. It is established that for 180 days of storage kinematic viscosity of the beverages with pectin decreased not more than 12%, that indicates a high level of pectin preservation. According to the results of the research, the author makes a conclusion that the use of pectin to preserve the color of beverages with natural colourants is not practical. It makes sense to use pectin in order to give the beverages functional properties, as well as to increase their viscosity and stability.

The policy of sustainable production has encouraged small batik businesses to shift to natural dyes as these are considered eco-friendly. However, the motivation behind juragan batiks’ embracing natural dyes still has some question marks attached. This qualitative study explains the motivation of the juragan batiks in using natural colourants in their production of batik warna alam and explores the significance of batik warna alam to juragan batik. We found the production of batik warna alam tended to be triggered by economic reasons not environmental consciousness. This related to the meaning of batik warna alam to maintaining the economic survival of the juragans. Juragans are convinced that batik warna alam is eco-friendly according to the indicators to which they subscribe: (1) the materials are found in their immediate surroundings; (2) the process causes no pollution or environmental destruction; and (3) the production does not pose a health threat to people, including workers. This study provides the insight that an eco-friendly-labelled production might not necessarily be motivated by a high level of environmental consciousness.

Attenuated total reflectance mid-infrared (ATR-MIR) spectra were collected from 480 grape skin extracts produced in a wide range of conditions. The conditions were created at different phases in parallel response surface RS-optimisation experiments aiming to maximise the total phenolics in red and white grape skin extractions by microwave-assisted (MAE) or conventional thermal (CTE) methods. Skins mixtures for six white and six red Australian commercial cultivars were prepared from grapes collected at veraison and harvest. The total phenolics were measured for individual extracts with the Folin-Ciocalteu method. Partial least squares (PLS1) regression was employed on the spectra to predict the total phenolics (TP) and colour (CIELAB chroma C*) of individual extracts. Models based on the raw spectra and their second derivative (Savitzky-Golay, 20 points) were examined using the full range of spectra 4000–400 cm−1, and sub-ranges: 4000–1100 cm−1, 1500–400 cm−1, 1500–1100 cm−1 and 1457–1168 cm−1. The PLS1 models based on the second derivative of the range of 4000–1100 cm−1 provided the best results for both TP and C*, for each skin colour. Overall, the residual predictive deviation (RPD) exceeded 3.0, indicating the PLS1 models' ability for fair classification, suitable for screening. A comparative analysis was performed for the range of 4000–1100 cm−1 between the spectra of white and red skin mixture extracts: the peaks at 3840 cm−1, 2940 cm−1, 2358 cm−1, 2197 cm−1, 2136 cm−1, 1725 cm−1, 1100 cm−1 and 1148 cm−1 are flagged to be investigated in further research. ATR-MIR spectroscopy can reduce the time and costs of TP and C* analyses in grape skin extracts. [ABSTRACT FROM AUTHOR]

The history of colour is fascinating from a social and artistic viewpoint because it shows the way; use; and importance acquired. The use of colours date back to the Stone Age (the first news of cave paintings); colour has contributed to the social and symbolic development of civilizations. Colour has been associated with hierarchy; power and leadership in some of them. The advent of synthetic dyes has revolutionized the colour industry; and due to their low cost; their use has spread to different industrial sectors. Although the percentage of coloured wastewater discharged by the textile; food; pharmaceutical; cosmetic; and paper industries; among other productive areas; are unknown; the toxic effect and ecological implications of this discharged into water bodies are harmful. This review briefly shows the social and artistic history surrounding the discovery and use of natural and synthetic dyes. We summarise the environmental impact caused by the discharge of untreated or poorly treated coloured wastewater to water bodies; which has led to physical; chemical and biological treatments to reduce the colour units so as important physicochemical parameters. We also focus on laccase utility (EC 1.10.3.2), for discolouration enzymatic treatment of coloured wastewater, before its discharge into water bodies. Laccases (p-diphenol: oxidoreductase dioxide) are multicopper oxidoreductase enzymes widely distributed in plants, insects, bacteria, and fungi. Fungal laccases have employed for wastewater colour removal due to their high redox potential. This review includes an analysis of the stability of laccases, the factors that influence production at high scales to achieve discolouration of high volumes of contaminated wastewater, the biotechnological impact of laccases, and the degradation routes that some dyes may follow when using the laccase for colour removal

Azaphilones are a class of fungal pigments, reported mostly in association with Monascus species. In Asian countries, they are used as food colourants under the name of "red yeast rice" and their production process is well described. One major limitation of current production techniques of azaphilones is that they always occur in a mixture of yellow, orange and red pigments. These mixtures are difficult to control and to quantify. This study has established a controlled and reproducible cultivation protocol to selectively tailor production of individual pigments during a submerged fermentation using another fungal species capable of producing azaphilone pigments, Talaromyces atroroseus, using single amino acids as the sole nitrogen source. The produced azaphilone pigments are called atrorosins and are amino acid derivatives of the known azaphilone pigment Penicillium purpurogenum–orange (PP-O), with the amino acid used as nitrogen source incorporated into the core skeleton of the azaphilone. This strategy was successfully demonstrated using 18 proteinogenic amino acids and the non-proteinogenic amino acid ornithine. Two cultivation methods for production of the pure serine derivative (atrorosin S) have been further developed, with yields of 0.9 g/L being obtained. Yielding pure atrorosins through switching from KNO3 to single amino acids as nitrogen source allows for considerably easier downstream processing and thus further enhances the commercial relevance of azaphilone producing fungal cell factories. [ABSTRACT FROM AUTHOR]

Copyright of Tekstilec is the property of University of Ljubljana, Faculty of Natural Sciences & Engineering, Department of Textiles and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Norbixin, a carotenoid extracted from the seeds of the annatto (Bixa orellana) plant, can be used in aqueous food applications, where other carotenoids are too hydrophobic to solubilise in a water environment. The aim of this work was to investigate the effect of pH, antioxidants and transition metal ions with and without hydrogen peroxide (H2O2) on the stability of norbixin in aqueous solutions as well as determining the interaction between these factors and light. The stability of norbixin in buffered aqueous solution stored in light or in the dark was evaluated using absorbance spectrophotometry. Light, reduced pH and metal ions both with and without H2O2 increased the bleaching of norbixin, whereas chelators and the natural antioxidants, ascorbic acid and tocopherol, reduced the bleaching of norbixin. Light significantly increased the loss of norbixin alone and in combination with the other factors. [ABSTRACT FROM AUTHOR]

Abstract Blends of jabuticaba, jussara and blueberry phenolic extracts were microencapsulated by spray drying using maltodextrin, gum arabic and whey protein concentrate (WPC) as the wall materials. Drying was performed with 10 different combinations of wall material mixtures (M1-M10). The samples, M1, M2 and M3, microencapsulated with the individual wall materials, maltodextrin, WPC and gum arabic, respectively, provided the highest encapsulation efficiency of anthocyanins. Furthermore, M1 and M2 presented the lowest hygroscopicity, while the mixtures containing WPC displayed the lowest solubility. All wall materials influenced the colour of the microcapsules, due to the different pH values of each encapsulated blend. The M2 blend was classified as a finished product and could be marketed as a high value-added protein concentrate, whereas, the other blends were considered natural colourants, with potential application in the food and cosmetics industry. Graphical abstract Unlabelled Image Highlights • The microcapsules presented high concentration of anthocyanins and phenolics. • Individual wall materials have promoted increased encapsulation efficiency. • Mixtures M1 and M3 provided the best rehydration profiles and particle size. [ABSTRACT FROM AUTHOR]

Currently, there are some examples of natural colourants with commercial use. However, these colourants are usually under-exploited, besides being obtained from a reduced number of plant or algal species. Accordingly, we propose using betalains obtained from an alternative plant species, Gomphrena globosa , which have a powerful colouring activity besides being strong antioxidants, as a novel ice-cream colourant. For comparison purposes, other ice-cream formulations were prepared, namely without colourants, added with commercial betalain or with Beta vulgaris extract. Besides evaluating the colour parameters L *, a * and b *, the nutritional parameters, individual sugars and fatty acids profiles were also studied. These parameters were evaluated throughout time, up to a maximum of 60 days of freeze (−22 °C) storage. Betacyanin quantification of each formulation was also performed to determine its maintenance along storage. In general, ice-creams prepared with G. globosa were similar (considering nutritional, colour, individual sugars and fatty acids profiles) to those including B. vulgaris extract, thereby validating the suitability of this alternative plant as a source of food colourants, particularly as ice-cream colourants. Furthermore, the positive effects induced by the addition of this natural colourant were maintained throughout storage time, as indicated by the markers distribution in the linear discriminant analysis. [ABSTRACT FROM AUTHOR]

Anthocyanins extracted from the pulp of the fruit of juçara palm (Euterpe edulis Mart.) were microencapsulated with maltodextrin in order to stabilise them. Photoacoustic spectroscopy was used to investigate the photostability of the microencapsulated samples. Complementary differential scanning calorimetry and scanning electron microscopy measurements were also performed. Lyophilised extract had 14 340.2 mg/L of total anthocyanins, and the microencapsulation effi ciency of 93.6 %. Temperature analysis showed that maltodextrin conferred protection up to 70 °C for 120 min. Scanning electron microscopy showed that the microencapsulated particles had a flake-like morphology with a smooth surface, characteristic of lyophilisation processes. In addition, when added to yogurt, a red colourant was predominant in the samples at pH from 1.5 up to 5.0. Thermal analysis showed a weak interaction between the sample and the encapsulating agent, and photoacoustic data indicated the photostability of the matrix when exposed to light. Yogurts containing microencapsulated anthocyanins showed a more intense pink colour than yogurts treated with pure dye, and sensory analysis demonstrated that they can have good acceptance on the market. Microencapsulation enabled the innovative application of anthocyanins from juçara palm fruit, and complementary techniques allied to the photoacoustic spectroscopy were effective tools for its evaluation.

[Display omitted] • Detailed analysis of acylated anthocyanins in red cabbage and sweet potato leaves. • Tradescantia pallida leaves contain uncommon tetraacylated anthocyanins. • Superior stability of acylated anthocyanins during heating of a test beverage. • Acylated anthocyanins exert brilliant colours over a broad pH range. • Uncommon vis spectra of Tradescantia anthocyanins are reported. Anthocyanins in red cabbage, sweet potato, and Tradescantia pallida leaves were characterised. A total of 18 non–, mono-, and diacylated cyanidins was identified in red cabbage by high performance liquid chromatography-diode array detection coupled to high-resolution and multi-stage mass spectrometry. Sweet potato leaves contained 16 different cyanidin- and peonidin glycosides being predominantly mono- and diacylated. In T. pallida leaves, the tetra-acylated anthocyanin tradescantin prevailed. The large proportion of acylated anthocyanins resulted in a superior thermal stability during heating of aqueous model solutions (pH 3.0) coloured with red cabbage and purple sweet potato extracts as compared to that of a commercial Hibiscus -based food dye. However, their stability was still outperformed by that of the most stable Tradescantia extract. Comparing vis spectra from pH 1–10, the latter had an additional, uncommon absorption maximum at approx. 585 nm at slightly acidic to neutral pH values, yielding intensely red to purple colours. [ABSTRACT FROM AUTHOR]

Natural ingredients are in demand and microbial processes to produce biocolourings are thus being developed. Penirillium spp. is particularly interesting for food applications. While microbial growth would be enhanced by using mycelium as inoculum, studies aimed at optimising pigments yields produced by Penirillium spp. have used spores as inoculum. A quantitative comparison of the pre-culture method for producing pigments by P. purpurogenum GH2 is provided in this work. Data analysis showed that simple growth models do not provide a suitable description of the fermentation process with mycelium as inoculum, which requires accounting for the effect of cell death. Probability density functions were applied to describe cell growth, substrate consumption and pigment production jointly and accurately. Specific production was 51% higher using mycelium as inoculum instead of spores, reaching a highest production of pigments with 10% (v/v) initial concentration being optimal (10.60 ± 0.40 units of Optical Density at 500 nm). Productivity of pigments per hour was 55% higher using mycelium as inoculum compared to spores. Three stochastic distributions provided equally good quantifications of all data (normal, gamma and Weibull). The three variables could be described by a same distribution function, with biomass being related to both live cells and accumulated dead residue. [ABSTRACT FROM AUTHOR]

Anthocyanins extracted from the pulp of the fruit of juçara palm (Euterpe edulis Mart.) were microencapsulated with maltodextrin in order to stabilise them. Photoacoustic spectroscopy was used to investigate the photostability of the microencapsulated samples. Complementary diff erential scanning calorimetry and scanning electron microscopy measurements were also performed. Lyophilised extract had 14 340.2 mg/L of total anthocyanins, and the microencapsulation efficiency of 93.6%. Temperature analysis showed that maltodextrin conferred protection up to 70 °C for 120 min. Scanning electron microscopy showed that the microencapsulated particles had a fl ake-like morphology with a smooth surface, characteristic of lyophilisation processes. In addition, when added to yogurt, a red colourant was predominant in the samples at pH from 1.5 up to 5.0. Thermal analysis showed a weak interaction between the sample and the encapsulating agent, and photoacoustic data indicated the photostability of the matrix when exposed to light. Yogurts containing microencapsulated anthocyanins showed a more intense pink colour than yogurts treated with pure dye, and sensory analysis demonstrated that they can have good acceptance on the market. Microencapsulation enabled the innovative application of anthocyanins from juçara palm fruit, and complementary techniques allied to the photoacoustic spectroscopy were eff ective tools for its evaluation. [ABSTRACT FROM AUTHOR]

Anthocyanins, one group of flavonoids, widely occur in vascular plants. The natural structural form is glycosides or acylglycosides of anthocyanidins. Anthocyanins produce a wide range of colours such as red, blue, purple and black in many flowers, vegetables and fruits, and they have been used as natural food colourants. However, anthocyanin containing products are susceptible to color deterioration during processing and storage. Nevertheless, their bright colors, water solubility that allows their incorporation into aqueous systems and a number of health benefits, such as, improved visual acuity, and anticancer and antiviral activities make them important and attractive objects for study. Anthocyanins can be used not only as food and beverage additive to obtain attractive natural coloration, but also for generating pharmaceutical and cosmetic products. This publication is a review work. [ABSTRACT FROM AUTHOR]

The current trend in European markets towards natural ingredients has stimulated the interest in natural colourants. When it is decided to replace a colourant, normally a synthetic colourant with a natural one, it is interesting to know how the colour would be perceived, by locating their coordinates in the a*b*-diagram. The colours of three red natural colourants and three red synthetic ones have been compared. The natural colourants would be visually perceived as less intense than the synthetic colourants; this perception could be a signal of high quality as recognised and accepted by consumers. The hue (hab) of the natural colourants was red-bluish while the synthetic ones showed a red-orange character and they were located in a wider area of hue, having values apart from the rest, thus they could not be replaceable. The synthetic colourants showed less colour differences than the natural ones when subjected to pH variations and heat treatments. [ABSTRACT FROM AUTHOR]

Consumers are increasingly avoiding foods containing synthetic colourants, which lead food industries to replace them by natural pigments, such as carotenoids, betalains, anthocyanins and carminic acid. Betalains are water-soluble nitrogen-containing pigments, composed of two structural groups: the red-violet betacyanins and the yellow-orange betaxanthins. This review synthesises the published literature on basic chemistry of betalains, their sources and chemical stability. Moreover, several works are mentioned which have demonstrated the potent antioxidant activity of betalains, which has been associated with protection against degenerative diseases. [ABSTRACT FROM AUTHOR]

Anthocyanin pigments in the fruit of mockstrawberry (Duchesnea indica Focke), were extracted with 0.1% HCl in ethanol, and the crude anthocyanin extract was purified by a C18 Sep-Pak cartridge open-column chromatography. High-performance liquid chromatography (HPLC) with photodiode array detection and mass spectrometry (MS) was applied for the isolation and composition analysis of anthocyanins in the fruit of mockstrawberry and their aglycones from acid hydrolysis. Three anthocyanins were found in the fruit of mockstrawberry and they were identified as cyanidin 3-O-rutinoside (61%), peonidin 3-O-rutinoside (34%), and petunidin 3-O-rutinoside (5%), respectively, by spectroscopic methods (UV-vis and MS). The two major anthocyanins were isolated by preparative HPLC, and their chemical structures were further characterised by H€1 NMR. On the basis of chromatographic data, the total anthocyanin content was 205 mg g-1 of the fresh fruit of mockstrawberry. [ABSTRACT FROM AUTHOR]

This paper provides an in-depth review of the natural colourants covering their classifications, sources, extraction techniques, application techniques in relation to different textile fibres and their advantages and challenges. The academic readers will find here an overview of the latest developments in extraction and application techniques of a variety of natural colourants. Almost all commercially produced natural fibres and the major synthetic fibres are found to be dyeable and printable with natural colourants. Although the production of natural colourants offers a lot of environmental benefits, their application techniques in textile colouration are not always sound for environment due to the need of synthetic mordants in colouration process. Advances in modern agriculture and biotechnology can play a key role in sorting the limitations of natural colourants and at the same time more and more investigations are still required to establish their cleaner application on textiles. [ABSTRACT FROM AUTHOR]

Abstract: The present work aimed both at improvement and extension of a previously developed process for the production of cactus pear juice. The total yield was increased by 10% through processing whole instead of peeled fruits and by further optimisation of pulp enzymation. As an alternative to HTST pasteurisation, cross-flow microfiltration was applied for non-thermal cactus pear juice preservation. Juice concentrates and fruit powders were produced by rotary evaporation and freeze drying at laboratory scale and compared to products obtained at pilot plant-scale applying a three-stage column evaporator and spray drying, respectively. To monitor process-related quality changes, the resulting products were characterised in terms of colour and selected quality parameters. For both juice concentrates and fruit powders, initial colour characteristics were retained. In addition to betanin isomerisation, C11-epimerisation of proline-betaxanthin was demonstrated to be a valuable indicator of the respective heat treatment applied. Whereas no adverse reactions were observed during juice production, non-enzymatic browning and HMF formation were found after concentration at pilot plant-scale and freeze drying, respectively. Industrial relevance: Although cactus pear meets all requirements for food colouring purposes, no attempt has been made so far to exploit this potential. The feasibility of processing cactus pear juice into concentrates and fruit powders was demonstrated in this study. In contrast to single-strength juice, concentrates and powders are easier to handle during transportation and storage and also open further fields of application that may promote cactus pear fruit processing at industrial scale in the future. [Copyright &y& Elsevier]

Abstract: The visual appearance and pigment stability of fruit juice blends from Opuntia and Hylocereus cacti and of betalain-containing model solutions derived therefrom were investigated at pH values ranging from 3 to 7. All samples were found to be stable as indicated by betalain contents as well as hue and chroma values over the complete pH range monitored. Both the juice and the purified betaxanthin solution from Opuntia ficus-indica cv. ‘Gialla’ were characterised by yellowish hues, while the juice and the purified betacyanin solution from Hylocereus polyrhizus displayed purplish tonalities. By blending the betaxanthin and betacyanin stock solutions, tailor-made hues covering the entire spectrum from bright yellow (h° =84) to purplish-blue (h° =333) were successfully produced. Since mixtures from purified betalains did not provide colour shades different from those obtained with raw cactus fruit juices, the use of the latter should be preferred both because of consumer-friendly labelling and improved pigment stability. [Copyright &y& Elsevier]

Abstract: Since no process has yet been established for the production of cactus pear juice, the present work aimed at the development of a betalain-based colouring foodstuff from Opuntia ficus-indica cv. ‘Gialla’ and cv. ‘Rossa’ of two seasons applying unit operations typical for fruit juice production. Complete separation of the peels from the pulp and removal of seeds were achieved by carborundum peeling of the frozen fruits and subsequent passing through a finisher. Furthermore, for improved filtration of cactus pear juice different enzyme preparations were tested to degrade pectic-like substances. To monitor quality changes in the course of processing, juice samples were analysed after each processing step in terms of colour and selected chemical parameters. While lightness (L*) and chroma (C*) increased during processing for both cultivars, hue angle (h°) remained unchanged for the yellow cultivar ‘Gialla’, but a slight shift towards red was observed for the red cultivar ‘Rossa’ after pasteurisation. Unexpectedly, even after repeated thermal treatment neither non-enzymatic browning nor HMF formation was observed in juices from both cultivars. Industrial relevance: Cactus pear represents a viable alternative to red beet for food colouring purposes: it neither exhibits negative sensorial impact nor high nitrate levels, but offers a broad colour range. However, no attempt has yet been made to benefit from this potential. The process developed is considered suitable for being scaled up to industrial-scale production thus opening an avenue for large-scale cactus pear fruit processing. [Copyright &y& Elsevier]

Today, natural colourants are emerging globally, leaving synthetic colourants behind in the race, due to the realisation that are safer and ecofriendly in nature. In this context, a brief review of natural colourant sources, their classification, chemical constituents responsible for producing different colours, its activities and effect of different mordants on the hue is discussed. [ABSTRACT FROM AUTHOR]

In this work, β-carotene was selected to develop a novel study, namely a food colorant system based on beeswax solid lipid particles obtained by hot melt dispersion. The obtained microparticles were characterized by optical microscopy, scanning electron microscopy, particle size analysis and Fourier Transform Infrared spectroscopy. It was observed that the obtained size can be modulated by using different amounts of emulsifier, as well as the dispersing capability. In a final stage, the obtained particles were tested concerning their colorant power by selecting a food matrix widely appreciated and consumed (mayonnaise). Moreover, the formulation providing the best hue and dispersibility (formulation containing 3% of Tween 80, and β-carotene at 5 mg/25 g of commercial mayonnaise) was analysed along a storage period of 15 days concerning colour, nutritional value and chemical composition. The results pointed out for colour stability and nutritional value maintenance, after 15 days under storage at 6 °C. • The encapsulation using β-carotene in a beeswax-based solid lipid particle was tested. • The particle size diminished as the emulsifier content increased. • The formulation with best hue and dispersibility contains 3% Tween 80. • The best formulation presented 5mg of β-carotene per 25g of mayonnaise. •The nutritional evaluation evidenced no significant differences for different samples. [ABSTRACT FROM AUTHOR]

The history of colour is fascinating from a social and artistic viewpoint because it shows the way; use; and importance acquired. The use of colours date back to the Stone Age (the first news of cave paintings); colour has contributed to the social and symbolic development of civilizations. Colour has been associated with hierarchy; power and leadership in some of them. The advent of synthetic dyes has revolutionized the colour industry; and due to their low cost; their use has spread to different industrial sectors. Although the percentage of coloured wastewater discharged by the textile; food; pharmaceutical; cosmetic; and paper industries; among other productive areas; are unknown; the toxic effect and ecological implications of this discharged into water bodies are harmful. This review briefly shows the social and artistic history surrounding the discovery and use of natural and synthetic dyes. We summarise the environmental impact caused by the discharge of untreated or poorly treated coloured wastewater to water bodies; which has led to physical; chemical and biological treatments to reduce the colour units so as important physicochemical parameters. We also focus on laccase utility (EC 1.10.3.2), for discolouration enzymatic treatment of coloured wastewater, before its discharge into water bodies. Laccases (p-diphenol: oxidoreductase dioxide) are multicopper oxidoreductase enzymes widely distributed in plants, insects, bacteria, and fungi. Fungal laccases have employed for wastewater colour removal due to their high redox potential. This review includes an analysis of the stability of laccases, the factors that influence production at high scales to achieve discolouration of high volumes of contaminated wastewater, the biotechnological impact of laccases, and the degradation routes that some dyes may follow when using the laccase for colour removal [ABSTRACT FROM AUTHOR]

• Red and purple-fleshed potatoes are rich sources of anthocyanins. • Pelargonidin and petunidin were the main anthocyanidin forms detected. • All aqueous extracts presented antioxidant, antibacterial and antifungal activities. • The incorporated extracts showed suitable sensory profiles and colour stability. • Aqueous extracts from coloured potatoes could be used as natural food colourants. Aqueous extracts from seven coloured potato varieties (three red-fleshed, three-purple fleshed, and one marble-fleshed) were studied for their anthocyanin content, in vitro biological activities, colouring properties and their potential application in the food industry. Acylated glycosides or pelargonidin and petunidin aglycones were identified as the main anthocyanin forms in the red and purple varieties, respectively. The total anthocyanin content among varieties ranged from 478.3 to 886.2 mg/100 g extract. All the extracts presented in vitro antioxidant, antibacterial and antifungal activities, whereas no toxic effects were detected. Finally, two selected extracts were tested as colourants in a soft drink formulation and presented suitable sensory profiles as well as high colour stability during a 30-day shelf-life when compared with the commercial colourant E163. Therefore, the tested extracts could be used as natural food colourants and considered for substituting the existing synthetic colouring agents. [ABSTRACT FROM AUTHOR]

The red-orange pigment producer strain Penicillium mallochii (TACB-16) used in this study was isolated from beech tree bark in Balikesir, Turkey, and was identified by molecular methods (P. mallochii Genbank accession number: MG591446). P. mallochii Rivera, Urb & Seifert was first isolated from the caterpillars Rothschildia lebeau and Citheronia lobesis on Costa Rica and is a new record for Turkey. Little is known of this fungus. In this study, the pigment production of P. mallochii on different media was characterised, and the factors affecting the pigment production and efficacy against the human GB cell line T98G cell viability/cytotoxicity were inspected. The results showed that the pigment was resistant to different temperatures and pH values. The ~250 base pair of the ITS region was sequenced and submitted to the Genbank. The blast result of the sequence showed that our isolate displayed maximum similarity (100%) to P. mallochii. Glioblastoma (grade-IV astrocytoma, WHO) is the most lethal subtype of glioma and the survival rate of GB patients is still low. Our results suggest that the pigment exhibits anti-proliferative effects on the T98G cell line. The present study is the first to assess the cytotoxic effect of the pigment on the survival of GB cells. Further studies and validations are needed, but we suggest that the pigment might be used for in vitro and in vivo studies, food industry and for future medical drug studies. • P. mallochii is a new pigment producer species. • The pigment produced by P. mallochii is resistant to different temperatures and pH values. • There is no literature on P. mallochii cytotoxic effect was studied. • The effective doses of the pigment to GB cells did not show any lethal properties in healthy cells. [ABSTRACT FROM AUTHOR]