Food Colorants Research Articles

Application of Active Packaging Films for Extending the Shelf Life of Red Meats: A Review

Meat is known for its high perishability and short shelf life if not properly packaged or stored. Packaging materials play a crucial role in preserving food quality, and there is a growing demand from consumers, industry professionals, and researchers for natural packaging materials that incorporate health-beneficial extracts. Additionally, there is an increasing emphasis on avoiding non-biodegradable plastics in order to reduce environmental pollution. Currently used polymers in food packaging typically feature properties such as oxygen barriers, moisture resistance, and oxidation inhibition, helping to prevent undesirable aromas, flavors, and colors in food. Packaging not only serves as a container for transportation but also prevents physical damage, maintains quality, and ensures food safety. In the pursuit of more sustainable solutions, various compounds are being explored for food packaging, including those derived from proteins, lipids, waxes, and polysaccharides. These materials can be combined with bioactive compounds, such as natural plant extracts, which provide antioxidant, antimicrobial, anti-inflammatory, and anticancer benefits. Different techniques, such as electrohydrodynamic processes and casting methods, are employed in the preparation of these packaging materials. This review highlights the applications and properties of polymers used in meat packaging and promotes the use of biodegradable materials as a viable solution to reduce environmental pollution.

Comparison of the natural and surfactant-modified zeolites in the adsorption efficiency of sunset yellow food dye from aqueous solutions

The removal of Sunset Yellow (E110) on natural zeolite and zeolite modified with the cationic surfactant cetyl pyridinium chloride (CPC) was studied using the adsorption method. The structural characteristics of the surfactant-modified zeolite (SMZ-CPC) were investigated using X-ray diffraction(XRD), Fourier transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) analysis, and the scanning electron microscopy (SEM) images. The effect of different parameters on the adsorption process, such as equilibration time and amount of adsorbent at 298 K, were determined using UV–Vis spectroscopy. The maximum dye removal percentage on SMZ-CPC was obtained with 0.08 g of adsorbent in 30 min. The results show that the zeolite modified with CPC surfactant (SMZ) has a higher adsorption capacity for Sunset Yellow than the unmodified zeolite (natural form). The experimental adsorption data were nonlinearly analyzed using isotherm equations such as Langmuir, Freundlich, Temkin, Langmuir-Freundlich (or Sips), and Extended Langmuir (EL). The experimental data were better fitted with the Sips isotherm. The adsorption kinetic data were analyzed using eight models in nonlinear forms: the pseudo-first-order (PFO), pseudo-second-order (PSO), integrated kinetic Langmuir (IKL), Elovich, intraparticle diffusion (IPD), mixed order rate equation (MOE), fractal-like pseudo-first-order (FL-PFO) and fractal-like pseudo-second-order (FL-PSO). According to the results of the coefficient of determination (R2), Elovich kinetic model well expressed E110 adsorption onto SMZ-CPC. Most of the dye removal takes place in less than 5 min and the maximum adsorption capacity is 5.06 mg/g. The results of this study show that zeolite modified with cationic surfactant is an effective adsorbent for removal anionic dyes from an aqueous solution.

Sustainable water treatment: Harnessing mining waste as catalysts for Sicomet green degradation

This paper presents a novel circular economy approach to water remediation that focuses on creating sustainable systems by utilizing mining waste from El-Ouenza, Tebessa, in the east of Algeria. Waste materials are employed as catalysts in Fenton and photo-Fenton processes. Two cases were studied: the conventional and the modified heterogeneous photo-Fenton at a pH of 3 and under modified pH conditions for degrading Sicomet Green food dye ZS120. Catalysts were characterized through various analyses. Catalyst performance and dye degradation were examined for raw and calcined waste at 500 °C. Parameters like catalyst amount, sodium sulfite concentration, oxalic acid, and pH were optimized for both systems, with and without ligand. The first system achieved 91.5 % mineralization using 0.15 g L−1 catalyst, pH of 3, and 0.45 mM Na2SO3 in 90 min under sunlight. The second reached 78.5 % efficiency with variable conditions. Kinetic models demonstrated a first-order model for both photo-Fenton degradation and mineralization under sunlight. These findings guide eco-friendly dye degradation via mining waste-based catalysts in photo-Fenton systems, supporting sustainable wastewater treatment.

Online determination of phycocyanin in vivo in Galdieria sulphuraria

ABSTRACT The extremophilic red alga Galdieria sulphuraria is well known for its metabolic capabilities with respect to organic carbon sources as well as its ability to produce the blue pigment phycocyanin (PC). The interest in PC as natural food colourant as well as nutraceutical is growing steadily. Therefore, a reliable quantification of PC accumulated by G. sulphuraria is crucial for establishing a production process. PC can be quantified through photometry but only after a laborious extraction procedure, which reduces the amount of data that can be gained from a cultivation. Hence, a faster PC determination method, with the potential to become an online method, is needed. In this study, we present a fast method for estimating the specific PC concentration based on in vivo absorbance spectra from cells of G. sulphuraria. A correlation with the PC concentration in the raw extract could be obtained, resulting in a 10-fold cross-validated coefficient of determination cR2 = 0.951. This makes extraction unnecessary in most cases. Especially in small-scale cultivation, where usually the available amount of biomass limits the number of measurements, this method presents a viable alternative to the extraction of PC.

Analisis Kadar Zat Warna Tartrazin pada Makanan dan Minuman dengan Metode Spektrofotometri UV-Vis

Tartrazine is a yellow dye that is included in synthetic dyes. Tartrazine is used to give a yellow color to the product so that it looks attractive. The maximum limit of tartrazine addition set by the Indonesian government is no more than 100 mg / Kg for food and 70 mg / Kg for soft drinks. This study aims to determine the content of tartrazine dye in food and beverage samples. Identification of tartrazine content was carried out qualitatively and quantitatively on 6 samples. The test results were analyzed using One Way-ANOVA. Qualitative identification was carried out by organoleptic testing, dye testing and testing with Thin Layer Chromatography (TLC). The organoleptic results on the 6 samples produced a yellow color with an average sweet fruit aroma. The color test results showed a reddish brown color. In the TLC test with n-butanol eluent: glacial acetic acid: Water (2:2:1) showed the presence of Rf close to standard tartrazine, this was also supported by the presence of a reddish brown mark after being sprayed with FeSO4 spot detector. Quantitative identification with UV-Vis Spectrophotometry produced a maximum wavelength of tartrazine at 427 nm with an average level in sample A of 23.61 mg/Kg, sample B 30.89 mg/Kg, sample C 0.63 mg/Kg, sample D 0.053 mg/Kg, sample E 12.46 mg/Kg and sample F 5.432 mg/Kg. The results of the study showed the presence of tartrazine content in all samples and entered the safe level category according to the specified limits. Data analysis provided significant differences in levels in each sample studied with a value of ? 0.05.

Safe Food Coloring Agent as an Alternative to Eosin Stain.

Introduction Eosin stain is a commonly used histological dye that selectively binds to acidic structures in cells, imparting a color between pink and red. Eosin stain can be harmful due to its chemical composition. Inhaling eosin stain in powder form or as aerosolized droplets can cause irritation in the respiratory tract. To overcome the toxic effects of eosin, many naturally available organic substitutes have been tested in histopathology laboratories, including rose extract, beetroot stain, and curcumin. These natural stain alternatives provide effective staining of tissue while ensuring minimal risk to laboratory personnel. Aim The study was conducted to evaluate the efficacy of food coloring agents over eosin stain in histopathological investigations. Materials and method The study was carried out in Kalinga Institute of Dental Sciences, Kalinga Institute of Industrial Technology (KIIT) (Deemed to be University), Bhubaneswar, India. The sample size comprised 30 oral mucosal lesion blocks. After the preparation of four micron thick sections from each block, one was stained with hematoxylin and eosin (H&E) stain and the other with a food coloring agent. Sections were kept in food color stain for three minutes. Next, the sections were dehydrated, cleared, and mounted in dibutylphthalate polystyrene xylene (DPX). To evaluate the staining with H&E and food color, each section was scored 0 for inadequate staining, one for adequate, and two for excellent staining. The tissue components stained for the study were red blood cells (RBCs), collagen fibers, muscle fibers, epithelium overall, basement membrane, cell membrane, desmosomes, keratin, cytoplasm, and nuclei. Kolmogorov-Smirnov tests were used to calculate the inferential statistics for the different variables between the groups. The distribution of the study sample was found to be not normal; therefore, a nonparametric test of significance was applied. Results All the tissue components showed excellent staining by H&E (score 2). Among the tissue components, in most of the samples, keratin, cytoplasm, and RBCs showed excellent staining (score 2) on par with the H&E stain. Other tissue components showed no staining (score 0) to adequate staining (score 1). The basement membrane and cell membrane staining were not adequate (score 0). The nuclear staining by hematoxylin was unaffected by food color and was on par with normal H&E staining. Conclusion We conclude that tomato red food color, which is non-toxic, safe for the health of laboratory personnel, easy to dispose of, and environmentally friendly, could be used as a replacement for eosin in the routine H&E techniques. Our observations could be strengthened by increasing the sample sizes and modifying the stain preparation to ensure positive staining of all tissue components, thereby enhancing the results.

Blue in Food and Beverages—A Review of Socio-Cultural, Economic, and Environmental Implications

The presented review concerns the cross-disciplinary approaches to the subject of blue food and blue colourants, the socio-cultural aspects of blue food and beverage consumption, human health effects, environmental impact, and economic aspects. Blue colour in relation to food is not only about improving visual appeal, to which the addition of food colouring is usually limited when the food is coloured in some way that does not encourage eating. It is also the rich and complex sociological side related to food, that is, not only the food itself but also the background, dishware, and light, depending on whether we want to encourage—to increase consumption—or discourage—to, for example, reduce the amount of food eaten for dietary purposes. The negative side of consuming and disposing of synthetic dyes and the health-promoting aspects of natural dyes are also mentioned, with the economic and environmental aspects of sourcing natural dyes being discussed. The food industry uses blue dyes not only for consumption, but also for food quality control, taking advantage of the pH-dependent colour change properties of the compound.

Paper strips-based narrowing colorimetry: An all-in-one strategy for rapid visual detection and adulteration identification of food dyes

Multi-task instrument-free technique for fast detection of harmful elements is of great significance for food safety, but it is still scarce. Herein, an all-in-one colorimetric strategy was initiated for rapid visual detection and adulteration identification of food dyes using narrow-band colorimetric paper strips as sorbents. Colorimetry of food dyes with improved sensitivity was achieved by compressing coloration region of full-length paper strips into a narrow band, while differential dyeing behaviors of natural/synthetic dyes toward paper strips enabled adulteration identification of food dyes in a single paper strip. As concept-to-proof assays, in-situ rapid detection of dyes in real foods and dye effluents were realized with LODs as low as 10−7 g/mL level, and the identifications of natural dyes adulterated with same-colored synthesized dyes were also achieved using fruit/vegetable juices as real samples. Finally, fine consistence between colorimetric results and the outcomes of smartphone-based digital image analysis along with instrumental techniques like spectrometry and HPLC consolidated the feasibility and reliability of this strategy.

Color, proximate composition, bioactive compounds and antinutrient profiling of rose

Rose (Rosa sp.) is one of the most important ornamentals which is commercialize for its aesthetic values, essential oils, cosmetic, perfume, pharmaceuticals and food industries in the world. It has wide range of variations that is mostly distinguished by petal color differences which is interlinked with the phytochemicals, secondary metabolites and antinutrient properties. Here, we explored the color, bioactive compounds and antinutritional profiling and their association to sort out the most promising rose genotypes. For this purpose, we employed both quantitative and qualitative evaluation by colorimetric, spectrophotometric and visual analyses following standard protocols. The experiment was laid out in randomized complete block design (RCBD) with three replications where ten rose genotypes labelled R1, R2, R3, R4, R5, R6, R7, R8, R9 and R10 were used as plant materials. Results revealed in quantitative assessment, the maximum value of lightness, and the luminosity indicating a brightening of rose petals close to a yellow color from rose accessions R4, and R10, respectively which is further confirmed with the visually observed color of the respective rose petals. Proximate composition analyses showed that the highest amount of carotenoid and β-carotene was found in R10 rose genotype, anthocyanin and betacyanin in R7. Among the bioactive compounds, maximum tocopherol, phenolic and flavonoid content was recorded in R8, R6 and R3 while R1 showed the highest free radical scavenging potentiality with the lowest IC50 (82.60 µg/mL FW) compared to the others. Meanwhile, the enormous variation was observed among the studied rose genotypes regarding the antinutrient contents of tannin, alkaloid, saponin and phytate whereas some other antinutrient like steroids, coumarines, quinones, anthraquinone and phlobatanin were also figured out with their presence or absence following qualitative visualization strategies. Furthermore, according to the Principal Component Analysis (PCA), correlation matrix and cluster analysis, the ten rose genotypes were grouped into three clusters where, cluster-I composed of R3, R4, R5, R8, cluster-II: R9, R10 and cluster-III: R1, R2, R6, R7 where the rose genotypes under cluster III and cluster II were mostly contributed in the total variations by the studied variables. Therefore, the rose genotypes R9, R10 and R1, R2, R6, R7 might be potential valuable resources of bioactive compounds for utilization in cosmetics, food coloration, and drugs synthesis which have considerable health impact.

Ag doped TiO2 anchored on metal free g-C3N4 for enhanced solar light activated photodegradation of a dye

Heterogeneous semiconductor photocatalysis has attracted researcher's attention in wastewater treatment owing to the improved surface area, optical properties, and charge transfer rate for boosted degradation of organic pollutants. Thus, the g-C3N4/Ag/TiO2 was prepared following a hydrothermal route for the degradation of azo dye tartrazine (TA) used as a food colourant under solar light. Before application, the composite and pristine materials were interrogated for physicochemical and structural properties using SEM, TEM, EDS, XPS, XRD, UV–vis DRS, PL, BET, Raman, and FTIR spectroscopy. The PL and electrochemical analysis revealed that the CNAT composite had a high charge transfer rate that was coupled with low charge carrier complexation. The degradation efficiency of 91 % was realized in 180 min and the rate of pseudo-first-order kinetics of 0.01143 min−1 was obtained. The CNAT catalyst also displayed high removal efficiency towards a cocktail of naproxen (NPX) and TA. The improved removal efficiencies stem from increased visible usage, reduced charge carrier compounding, and formation of Z-scheme heterojunction with high redox capabilities. The total organic carbon removal reached 95 % while CNAT showed high convincing stability even after four cycles. Given the above results, the hydrothermally prepared composite catalyst can be extended to other organic pollutants such as pharmaceuticals, pesticides, and reduction of inorganics.

Evaluating the potential of stabilised betacyanins from fermented red dragon fruit (Hylocereus polyrhizus) drink: Sustainable colouration and antioxidant enhancement of stirred yoghurt

Nowadays, the wide use of synthetic food colourant, Allura Red has elevated negative perceptions among consumers. As food industry players strive towards satisfying consumers’ demands, exploring new sustainable natural colourants with multifunctional properties (like betacyanins) has emerged as a novel concept. This study aimed to evaluate the potential of a functional fruit drink, Improved-FRDFD-dH2O [contained betacyanins of fermented red dragon fruit drink stabilised by 0.4 % xanthan gum and 0.5 % carboxymethyl cellulose hydrocolloid mixture solution and 0.2 % citric acid] to serve as a sustainable and stable functional liquid colourant in yoghurt. The 8-week refrigerated storage study revealed the betacyanins content in the yoghurt added with E162 experienced the lowest stabilities in terms of betacyanins content (>30 % degradation), viscosity (>15 % reduction), pH, LAB viability and antioxidant activity. In contrast, the Improved-FRDFD-dH2O was able to maintain the yoghurt's viscosity, syneresis, pH and LAB viability without any significant change. The betacyanins of Improved-FRDFD-dH2O had excellent stability in the yoghurt (<5 % degradation), showing only a minimal difference (ΔE<1.5) in total colour changes and being able to retain >86 % of the initial antioxidant activity by the end of storage. These findings support the Improved-FRDFD-dH2O as a sustainable functional colourant with antioxidant properties for producing beneficial yoghurt.

Magnetic-responsive sensors based on polydopamine macromolecules for highly sensitive detection of trace food colorant residues

As a kind of unique biomimetic macromolecule, polydopamine (PDA) have prominent in-situ reduction ability and interfacial adhesion. In this work, combined with in-situ reduction ability of PDA and excellent magnetic response performance of nickel foam (NF), a strategy was designed to fabricate a series of NF@PDA@AgNPs as magnetic-responsive surface enhancement Raman scattering (SERS) substrates for highly sensitive Rhodamine B (RhB) detection in chili powder. With crystal violet (CV) as probe molecule, the detection limit of SERS substrate could achieve 10−10 M, and the enhancement factor was as high as to 2.22 × 107. In addition, the NF@PDA@AgNPs SERS substrates showed excellent magnetic separation efficiency, good SERS uniformity and storage stability. More importantly, these substrates could achieve highly efficient collection and sensitive detection of RhB residues in chili powder by magnetic adsorption method, and the detection of limit was as low as to be 10−6 g/g. These NF@PDA@AgNPs substrates would be a great prospect for rapid and efficient pernicious contaminant detection in the chemical and biological fields.

Formulation of Natural Food Coloring Granules from Dragon Fruit Peel Extract (Hylocereus polyrhizus) and Effectiveness Test in Reducing Blood Glucose Levels

Anthocyanin is one of the many compounds in dragon fruit skin that can be used as an antioxidant. Dragon fruit skin can also lower blood glucose levels. The fact that cases of diabetes mellitus are increasing every year shows that this disease needs serious treatment. This study aims to make dragon fruit skin extract formulated in the form of granules and make dragon fruit skin extract granules that meet the requirements as natural food coloring and to determine the content and effectiveness of dragon fruit skin extract (Hylocereus polyrhizus) which can lower blood glucose levels. This research method is experimental. The One Way Anova test and the Tukey HSD post-hoc test were used to analyze the data. The outcomes showed that there were 9 granule recipes that met the assessment test necessities. After being induced by 20% fructose solution, the glucose level study revealed that the treatment of dragon fruit skin extract at 100, 200, and 400 mg / kgBW was able to lower blood glucose levels in test animals. Winged serpent natural product skin concentrate can be formed as granules. Equations 2 and 3 produce the best tone. The consequences of the review reasoned that winged serpent natural product skin remove (Hylocereus polyrhizus) at dosages of 100, 200 and 400 mg/kgBW was viable in decreasing blood glucose levels in guinea pigs prompted by 20% fructose arrangement and a portion of 200 mg/kgBW gave an impact of lessening blood glucose levels that was practically equivalent to the positive control.

Formation of CdTe core and CdTe@ZnTe core-shell quantum dots via hydrothermal approach using dual capping agents: deciphering the food dye sensing and protein binding applications.

Excessive use of food coloring agents in the food industry to make the food more attractive or improve the taste has caused various health and ecological problems. Therefore, it is necessary to develop a reliable, sensitive, and selective sensing probe to detect food dyes in different food products for future industrial processing and biosafety. In recent decades, surface-functionalized quantum dots (QDs), owing to their unique optical properties, have gained tremendous interest for a wide range of applications, including biomedical, bioimaging and sensing applications. Herein, we have reported the synthesis of excellent colloidal stable and highly luminescent CdTe core and CdTe@ZnTe core-shell QDs using dual functionalizing agents, polyvinyl pyrrolidone and vitamin C. The synthesized QDs were explored as excellent sensing probes for the food dyes carmoisine, Ponceau 4R and tartrazine with limit of detection (LOD) values of 0.097 ± 0.006, 0.147 ± 0.001 and 0.044 ± 0.001 μM for CdTe-PVP QDs and 0.079 ± 0.001, 0.114 ± 0.002 and 0.042 ± 0.001 μM for CdTe@ZnTe-PVP QDs, respectively. The sensitivity of the synthesized QDs for the food dyes was also investigated in real samples (soft drinks and medications). Moreover, considering the potential effects of QDs as therapeutics or nano-drug carriers, the interactions between the synthesized QDs and carrier protein human serum albumin (HSA) were investigated. The binding affinity was observed to be in the order of 104 M-1. QDs were found to quench the intrinsic fluorescence of HSA, and both types of quenching (static and dynamic) occur via electrostatic interactions in association with hydrophobic forces without any significant alteration in the protein structure.

Photodegradation and kinetics studies of food dyes by advanced oxidative processes

In this research, the advanced oxidative processe (AOP), Photo-Fenton was applied and kinetics studies were realized by the photodegradation of bright blue FCF, ponceau 4R red and tartrazine yellow food dyes. The AOP Photo-Fenton (combining iron/hydrogen peroxide (H2O2, 36% v/v) /ultraviolet (UV) light, processes were studied. The reaction time, concentration and time of exposure to UV light were evaluated for the food dyes described with both AOP. The results exhibited good effectiveness by Photo-Fenton in the photodegradation of bright blue FCF, ponceau 4R red and tartrazine yellow food dyes. The Photo-Fenton (Fe/H2O2/UV light) exposed high photodegradation in shorter reaction time for all food dyes studied. The kinetics studies performed from the photodegradation food dyes data, showed exponential behavior of the concentration as a function of time, given the first-order exponential with good correlation coefficient, R2 = 0,99 for bright blue FCF, ponceau 4R red and tartrazine yellow food dyes. Thus, we can highlight that the Photo-Fenton stand out as an important methodology for treating industrial effluents containing food dyes, combining the advantages of ease, effectiveness and low cost in the process.

California passes bill to ban 6 dyes in school food

California passes bill to ban 6 dyes in school food

Development of bio-active cotton fabric coated with betalain extract as encapsulating agent for active packaging textiles

The development of bio-active cotton fabric based on natural polymers and pigments has been a significant material for biodegradable textile packaging in recent years. Betalain extracted (BE) from Red beet root (RBR) is a rich source of natural pigments and has potential health benefits as an antioxidant and in biological activities which used as food, beverage, and drug colorant. However, BE pigments are photochromically unstable and have interest applications, thereby motivating the use of microencapsulation technology to maintain their stability and increase their shelf lifetime. Thus, in the present work Incorporating BE into gelatinized corn starch (GS) and Arabic gum (AG) for manufacturing stabilized BE microcapsules with tunable antioxidant and biological properties by freeze-drying method. The produced encapsulating agent (EA) powders were analyzed by scanning electron microscope (SEM) for particle morphology and FTIR of selected EA was carried out. Monitoring of coloring strength values (K/S) and Color parameters before and after storage as well as storage stability of these microcapsules at different pH’s was also studied. The current study was performed to design multifunctional cotton fabric, for this purpose the cotton fabric was treated with keratin to improve its affinity toward 100 % BE, with and without (BE) EA were determined using a pad dry process. The chemical properties, physical properties, mechanical properties, thermal stability, and functional properties of the coated fabrics with and without (BE) as well as color parameters were determined. The results showed that the fabric coated with 100 % BE and 30 % BE incorporating or encapsulating with 60 % GS and 10 % AG exhibited good mechanical properties, excellent thermal stability, and significant antioxidant and antimicrobial activity compared to the uncoated fabric. The antioxidant release of BTE from the fabric coated with 60/10/30 EA was controlled by diffusion. According to the results, the developed multifunctional coated fabrics with BE encapsulating agent can be considered as a good potential material for active packaging textiles for various applications.

Triple channel fluorescence Na-Ca-Cl-doped carbon dots for erythrosine detection in food samples and living cells

It is an ongoing and imperative need to monitor food colorants, for unsafe food is a terrifying threat to human health and economy. Here new Na-Ca-Cl-doped carbon dots (CDs) was fabricated by hydrothermal treatment of Miswak and m-phenylenediamine (mPD). The CDs were green-emitting with three distinctive emission centers, displaying a high quantum yield of 47 %. The CDs were able to assess erythrosine in the triple channels based on their fluorescence quenching by erythrosine because of the inner filter effect, displaying high sensitivity and selectivity. Also, the quantitative measurement of erythrosine utilizing the CDs was realized in food samples and in living cells with admirable fluorescence stability and appealing biocompatibility, representing the first report on exploiting CDs for erythrosine sensing in living cells. Collectively, the CDs provide a simple efficient platform for erythrosine sensing in solutions, food samples, and living cells, broadening the implements of CDs as bioprobes for food colorants.

Synchronous Bioproduction of Betanin and Mycoprotein in the Engineered Edible Fungus Fusarium venenatum.

Sustainable production of edible microbial proteins and red food colorants is an important demand for future food. Therefore, creation of a chassis strain that can efficiently synthesize both products is extremely necessary and meaningful. To realize this envision, a CRISPR/Cas9-based visual multicopy integration system was successfully developed in Fusarium venenatum. Subsequently, the de novo synthesis of the red food colorant betanin was achieved in the engineered F. venenatum using the above system. After fermentation optimization, the final yields of betanin and mycoprotein reached 1.91 and 9.53 g/L, respectively, when the constant pH naturally decreased from 6 to 4 without the addition of acid after 48 h of fermentation. These results determine a highly suitable chassis strain for the microbial biomanufacturing of betanin, and the obtained engineered strain here is expected to expand the application prospect and improve economic returns of F. venenatum in the field of future food.

The effect of rosé wine colors on expected flavor and tastiness: A cross-modal correspondence explanation

How and why do wines with different colors influence consumer responses? Despite strong evidence from research on cross-modal correspondences that food and drink colors influence flavor perceptions and subsequent consumer responses, it is unclear from the wine literature whether consumers prefer paler or slightly darker colors of rosé. The aim of this research is twofold: (1) identify from an existing set of (relatively pale) prototypical color shades of Rosé de Provence what specific color (paler vs. slightly darker) leads to more positive consumer responses and (2) shed light on the underlying mechanisms that explain this relationship. Using a large sample of French wine consumers (n = 601), we test our hypotheses via a within-subjects design experiment. We first examined the effect of five shades of Rosé de Provence wines (nacre, light melon, sand, melon, and peach) on consumer responses (willingness to pay, willingness to buy, color liking). To further investigate the underlying roles of fruity flavor and expected tastiness (in that order), we conducted a series of two-condition within-subjects serial mediations. Our findings consistently show more positive consumer responses for Rosés de Provence with peach and melon shades (i.e., slightly darker colors) compared to nacre, light melon, and sand shades (i.e., paler colors). Further, a stronger association between slightly darker colors and fruity flavor enhances expected tastiness, which leads to more positive consumer responses. Our findings provide key theoretical contributions and managerial implications by suggesting consumer responses for Rosés de Provence and corresponding explanations based on cross-modal correspondences.