Characterization of major betalain pigments -gomphrenin, betanin and isobetanin from Basella rubra L. fruit and evaluation of efficacy as a natural colourant in product (ice cream) development

Phytochemicals and UHPLC-QTOF-HRMS characterisation of bioactives of butterfly pea (Clitoria ternatea L.) seeds and their antioxidant potentials

Clitoria ternatea Linn. (Fabaceae) is a medicinal and ornamental plant, widely used in Ayurvedic and Chinese medicine. There is no strong scientific evidence on the consumption of the tender fruits/seeds of blue- and white-flower plants as vegetables. Analysis of the nutrient composition revealed that the total carbohydrate, protein, and lipid were highest in the mature-stage seeds of both varieties. UHPLC analysis revealed the presence of rutin (1.66 mg%) as the major compound. LC-HRMS confirmed the presence of other bioactives, such as sinapic acid (m/z 223), catechin derivatives (m/z 305 and m/z 153), quercetin (m/z 463), etc., as well. The ascorbic acid content was found to be highest in blue-flowered plant seeds (18.10 mg/100 g). Analysis of antioxidant activity displayed the superiority of immature seeds over mature seeds. The research shows that these seeds are rich in nutrients and bioactives, which may have use in the food and pharmaceutical industries.

Comparative Transcriptomic Analysis of the Metabolism of Betalains and Flavonoids in Red Amaranth Hypocotyl under Blue Light and Dark Conditions

Amaranth plants contain abundant betalains and flavonoids. Anthocyanins are important flavonoids; however, they cannot coexist in the same plant with betalains. Blue light influences metabolite synthesis and hypocotyl elongation; accordingly, analyses of its effects on betalain and flavonoid biosynthesis in Amaranthus tricolor may provide insight into the distribution of these plant pigments. We analyzed the betalain and flavonoid content and transcriptome profiles in amaranth hypocotyls under blue light and dark conditions. Furthermore, we analyzed the expression patterns of key genes related to betalains and flavonoids. Amaranth hypocotyls were shorter and redder and showed higher betalain and flavonoid content under blue light than in dark conditions. Key genes involved in the synthesis of betalains and flavonoids were upregulated under blue light. The gene encoding DELLA was also upregulated. These results suggest that blue light favors the synthesis of both betalains and flavonoids via the suppression of bioactive gibberellin and the promotion of DELLA protein accumulation, which also suppresses hypocotyl elongation. The metabolite profiles differed between plants under blue light and dark conditions. These findings improve our understanding of the environmental cues and molecular mechanisms underlying pigment variation in Amaranthus.

Amaranth Seeds and Sprouts as Functional Ingredients for the Development of Dietary Fiber, Betalains, and Polyphenol-Enriched Minced Tilapia Meat Gels

There is an increasing interest in the development of meat processed products enriched with antioxidant dietary fiber to augment the consumption of these health beneficial compounds. This study aimed to evaluate the nutritional, nutraceutical, and antioxidant potential, as well as the physicochemical properties of minced tilapia fillets (meat) gels with added amaranth seed or sprout flours (0%, 2%, 4%, 8%, and 10% w/w). Dietary fiber content was significantly increased with the addition of amaranth seed (1.25-1.75-fold) and sprout flours (1.99-3.21-fold). Tilapia gels with added 10% amaranth seed flour showed a high content of extractable dihydroxybenzoic acid and cinnamic acid, whereas the addition of 10% amaranth sprout flour provided a high and wide variety of bioactive compounds, mainly amaranthine and bound ferulic acid. The addition of amaranth seed and sprout flours increased hardness (1.01-1.73-fold) without affecting springiness, decreased luminosity (1.05-1.15-fold), and increased redness and yellowness. Therefore, amaranth seed and sprout flours could be used as functional ingredients for the development of fish products rich in bioactive compounds.

Structural Studies on Diverse Betacyanin Classes in Matured Pigment-Rich Fruits of Basella alba L. and Basella alba L. var. ‘Rubra’ (Malabar Spinach)

Identification of betacyanins in Basella alba L. and Basella alba L. var. ‘Rubra’ fruits was performed by low- and high-resolution mass spectrometry (LRMS and HRMS) as well as ¹H, ¹³C and two-dimensional NMR which revealed hitherto completely not known betacyanin classes in the plant kingdom. Especially, the presence of unique nitrogenous acyl moieties in the structures of the pigments was ascertained by the HRMS Orbitrap detection. Except for detected polar betacyanin glycosylated derivatives, presence of a series of previously not reported pigments such as malonylated betanidin 6-O-β-glusosides with their acyl migration isomers along with the evidence of the 3′′-hydroxy-butyrylated betacyanins is reported. The first complete NMR data were obtained for novel and principal acylated gomphrenins with hydroxycinnamic acids: 6′-O-E-caffeoyl-gomphrenin (malabarin), 6′-O-E-sinapoyl-gomphrenin (gandolin), 6′-O-E-4-coumaroyl-gomphrenin (globosin) and 6′-O-E-feruloyl-gomphrenin (basellin).

Betalains and their applications in food: The current state of processing, stability and future opportunities in the industry

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Several fruits, plants, and roots are sources of betalains.

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Betalains analysis can be performed by spectroscopic and chromatographic methods.

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Betalains extraction techniques have advantages and disadvantages.

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Betalains encapsulation increases its stability and possibility of incorporation in foods.

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The incorporation of betalains in food packaging is a potential application.

Betalains are water-soluble nitrogenous pigments with coloring properties and antioxidant activities, which is why they have been incorporated into several foods. However, their use is limited by their instability in response to different factors, such as, pH, oxygen, water activity, light, metals, among others. In this work, a review of up-to-date and relevant information is presented on the primary natural sources of betalains. Additionally, the advantages and disadvantages of the primary betalain extraction techniques are discussed and compared. The results of these studies were focused on the stability of betalains when incorporated into foods, either in pure or encapsulated form, and they are discussed through different technologies. Lastly, the most relevant information related to their stability and a projection of their promising future applications within the food industry is presented.

Effects of Betanin on Pasting, Rheology and Retrogradation Properties of Different Starches

As a natural pigment with high antioxidative activity, betanin is underutilized owing to less attention. This study aimed to investigate the impact of betanin on pasting, rheology and retrogradation properties of rice, potato and pea starches. Betanin decreased the peak, trough and final viscosity of rice and potato starches, but increased those of pea starch. Rheology measurements implied that betanin had the greatest effect on the hysteresis loops and dynamic modulus of potato starch. Betanin endowed starch pastes with a vivid red appearance and maintained the color of the starch pastes during storage. XRD analysis indicated that betanin weakened the diffraction intensities and reduced the crystallinity of the retrograded starches. Meanwhile, betanin reduced the short-range ordered structure of the retrograde starches. The results of DSC analysis found that betanin significantly depressed the retrogradation enthalpy and retrogradation rate, implying that the long-term retrogradation of starches was delayed. Furthermore, the changed morphology of the retrograded starches was observed. These results suggested that betanin could be applied as an excellent colorant and inhibitor of retrogradation in foods such as bread and pastry products.

Betalain plant sources, biosynthesis, extraction, stability enhancement methods, bioactivity, and applications

Betalains are plant pigments with functional properties used mainly as food dyes. However, they have been shown to be unstable to different environmental factors. This paper provides a review of (1) Betalain plant sources within several plant families such as Amaranthaceae, Basellaceae, Cactaceae, Portulacaceae, and Nyctaginaceae, (2) The biosynthesis pathway of betalains for both betacyanins and betaxanthins, (3) Betalain extraction process, including non-conventional technologies like microwave-assisted, ultrasound-assisted, and pulsed electrical field extraction, (4) Factors affecting their stability, mainly temperature, water activity, light incidence, as well as oxygen concentration, metals, and the presence of antioxidants, as well as activation energy as a mean to assess stability, and novel food-processing technologies able to prevent betalain degradation, (5) Methods to increase shelf life, mainly encapsulation by spray drying, freeze-drying, double emulsions, ionic gelation, nanoliposomes, hydrogels, co-crystallization, and unexplored methods such as complex coacervation and electrospraying, (6) Biological properties of betalains such as their antioxidant, hepatoprotective, antitumoral, and anti-inflammatory activities, among others, and (7) Applications in foods and other products such as cosmetics, textiles and solar cells, among others. Additionally, study perspectives for further research are provided for each section.

Multi-colored shades of betalains: recent advances in betacyanin chemistry

Covering: 2001 to 2021Betacyanins cover a class of remarkable natural red-violet plant pigments with prospective chemical and biological properties for wide-ranging applications in food, pharmaceuticals, and the cosmetic industry. Betacyanins, forming the betalain pigment group together with yellow betaxanthins, have gained much attention due to the increasing social awareness of the positive impact of natural products on human health. Betalains are commercially recognized as natural food colorants with preliminarily ascertained, but to be further investigated, health-promoting properties. In addition, they exhibit a remarkable structural diversity based on glycosylated and acylated varieties. The main research directions for natural plant pigments are focused on their structure elucidation, methods of their separation and analysis, biological activities, bioavailability, factors affecting their stability, industrial applications as a plant-based food, natural colorants, drugs, and cosmetics as well as methods for high-yield production and stabilization. This review covers period of the last two decades of betacyanin research. In the first part of the review, we present an updated classification of all known betacyanins and their derivatives identified by chemical means as well as by mass spectrometric and NMR techniques. In the second part, we review the current research reports focused on the chemical properties of the pigments (decarboxylation, oxidation, conjugation, and chlorination reactions as well as the acyl group migration phenomenon) and describe the semi-synthesis of natural and artificial fluorescent betalamic acid conjugates, showing various prospective research directions.

Physicochemical Composition and Characterization of Bioactive Compounds of Mulberry (Morus indica L.) Fruit During Ontogeny

Mulberry fruit is well recognized as one of the richest sources of bioactive compounds. We investigated the physicochemical composition and characterized the bioactive compounds during different ripening stages of mulberry (Morus indica) fruit and evaluated their anti-quorum sensing activity on Chromobacterium violaceum. The proximate components such as carbohydrates, proteins and lipids were found to be high in the ripe fruit compared to unripe and mid-ripe fruit. The ripe fruit contained higher content of total phenolics and flavonoids (336.05 and 282.55 mg/100 g fresh weight (FW), respectively). Epicatechin and resveratrol were the major polyphenols detected in the fruit with the range 5.13-19.46 and 4.07-14.45 mg/100 g FW, respectively. Chlorogenic acid and myricetin were predominant in the unripe and mid-ripe fruit (7.14 and 1.84 mg/100 g FW, respectively). The fruit was found to be an excellent source of anti-diabetic compound 1-deoxynojirimycin. The highest content of 1-deoxynojirimycin was present in the mid-ripe fruit, with a content of 2.91 mg/100 g FW. Furthermore, fruit extracts exhibited anti-quorum sensing activity against Chromobacterium violaceum by effectively inhibiting violacein production. Ripe fruit extracts showed the highest activity of 76.30% at 1 mg/mL and thus, could be used as a potent anti-quorum sensing agent. The results could be promising in the selection of appropriate developmental stages for M. indica fruit commercial exploitation in the food formulations rich in potential health components.

Pterocarpus santalinus L. extract mitigates gamma radiation-inflicted derangements in BALB/c mice by Nrf2 upregulation

Plant-based natural extracts contain several nutrients and bioactive compounds, such as phenolics and flavonoids, that possess various health-promoting activities. This study investigated the effects of polyphenols from Pterocarpus santalinus hydroalcoholic extract (PSHE) against gamma radiation-induced derangements via the upregulation of Nrf2. Ultra High Performance Liquid Chromatography Coupled to High Resolution Mass Spectrometry (UHPLC-HRMS/MS) analysis was performed to identify the possible radioprotectors. In vivo and in vitro studies, namely Real-Time-PCR (RT-PCR) analysis, Reactive Oxygen Species (ROS) scavenging activity, lipid peroxidation and GSH levels, DNA damage and cell death studies, anti-inflammatory (Sandwich ELISA), immunomodulatory studies (antibody staining), and model free radical scavenging assays, were performed. Vanillic acid, protocatechuic acid, para-hydroxybenzoic acid, chlorogenic acid, TNF-α inhibitor (Eudesmin), isoflavone (Daidzein 7-o-glucoside), astragalin (Kaempferol 3-o-glycoside), and other polyphenols were identified in PSHE using UHPLC-HRMS/MS analysis. Prophylactic administration of PSHE (-1 h) rendered more than 33% survival in mice exposed to 8 Gy whole-body-irradiation with increased mice survival and recovery of bone marrow and spleen cellularity. Real-time RT-PCR analysis showed that PSHE treatment (50 µg/mL) upregulated Nrf2, HO-1, and GPX-1 in mice splenocytes. At 50 µg/mL, PSHE reduced ROSscavenging activity, mitochondrial and spleen membrane lipid peroxidation levels, DNA damage, and cell death, and increased GSH levels. At 10 µg/mL, PSHE treatment diminished the content of IL-6 and TNF-α. At 50 µg/mL, PSHE suppressed lymphocyte proliferation. These findings indicate that polyphenols of PSHE possess marked antioxidant, anti-inflammatory, and immunomodulatory capacities, which play important roles in the prevention of radiation damage.

Antioxidant and Cytoprotective Properties of Plant Extract from Dry Flowers as Functional Dyes for Cosmetic Products

Nowadays, natural dyes are expected by the cosmetic and food industries. In contrast to synthetic dyes, colorants derived from natural sources are more environmentally friendly and safer for human health. In this work, plant extracts from Gomphrena globasa L., Clitoria ternatea L., Carthamus tinctorius L., Punica granatum L. and Papaver rhoeas L. as the natural and functional dyes for the cosmetics industry were assessed. Cytotoxicity on keratinocyte and fibroblast cell lines was determined as well as antioxidant and anti-aging properties by determining their ability to inhibit the activity of collagenase and elastase enzymes. In addition, the composition of the extracts was determined. The obtained extracts were also applied in face cream formulation and color analyses were performed. It has been shown that the obtained extracts were characterized by no cytotoxicity and a high antioxidant potential. The extracts also show strong ability to inhibit the activity of collagenase and moderate ability to inhibit elastase and provide effective and long-lasting hydration after their application on the skin. Application analyses showed that the extracts of P. rhoeas L., C. ternatea L. and C. tinctorius L. can be used as effective cosmetic dyes that allow for attainment of an intense and stable color during the storage of the product. The extracts of P. granatum L. and G. globasa L., despite their beneficial effects as active ingredients, did not work effectively as cosmetic dyes, because cosmetic emulsions with these extracts did not differ significantly in color from emulsions without the extract.

Evaluating the effect of additives on stability of betacyanin pigments from Basella rubra in a model beverage system during storage

The effect of selected additives (catechin, ascorbic acid, β-cyclodextrin and EDTA) on the stability of betacyanin pigments from Basella rubra in a model beverage system was investigated and they exhibited remarkable outcomes. The major betacyanin pigment in B. rubra extract was identified to be gomphrenin-I using HPLC-ESI-MS analysis method. The degradation kinetics of betacyanin pigment in the model beverage variants was established, and temperature was found to be the most detrimental factor. If effect of additives on stability of B. rubra betacyanin pigments in model beverage stored at 4 °C in the absence of light and oxygen is considered, maximum stabilizing effect was demonstrated by catechin (t_1/2 203.9 days) followed by EDTA (t_1/2 187.3 days) and then β-cyclodextrin (t_1/2 144.4 days) when compared with control (t_1/2 119.5 days) whereas, ascorbic acid acted as a prooxidant and reduced storage stability of the pigment (t_1/2 78.8 days).

Effects of Ultra-Sonication and Agitation on Bioactive Compounds and Structure of Amaranth Extract

Amaranth is an excellent source of various bioactive compounds that could be beneficial in the prevention of some human diseases. This study investigated the extraction and characterization of bioactive compounds from amaranth using ultra-sonication and agitation at 30, 50 and 70 °C. Color L* values showed significant (p < 0.05) differences at 70 °C between ultra-sonication and agitation. Ultra-sonication temperature had significant effect on L* and a* values whereas agitation temperature did not have a significant effect on L*, a* and b* values. No significant (p < 0.05) differences were found in terms of total phenol, total flavonoid, DPPH•+, ABTS+ scavenging activity, betacyanins, betaxanthin and betanicaicd between ultra-sonication and agitation. However, temperature had a significant (p < 0.05) effect on total phenol (8.64-10.598 mg/g), DPPH+scavenging activity (84.36-94.44%), betacyanins (4585.95-5325.32 mg/100 g), betaxanthin (1312.56-1524.06 mg/100 g) and betalamic acid (1408.15-1790.22 mg/100 g) in ultra-sonication. Higher temperature (70 °C) showed greater amount of arbutin and hydroxybenzoic acid than those of lower temperature (30 °C) for both extraction methods. Meanwhile, temperature did not affect vanillic acid, p-coumaric acid and ferulic acid for both samples. Fourier-transformed infrared (FTIR) spectrometry showed that ultra-sonication and agitation resulted in similar effect on the structure of amaranth extracts. Higher temperature was correlated with bioactive compounds, which were observed by principal component analysis (PCA). Therefore, agitation at 70 °C could be used as an alternative for ultra-sonication to improve the bioactive compounds and antioxidant activities of amaranth. In addition, agitation and ultra-sonication techniques might be served as an alternative of conventional technique.

Nanoliposomal encapsulation mediated enhancement of betalain stability: Characterisation, storage stability and antioxidant activity of Basella rubra L. fruits for its applications in vegan gummy candies

Betalains are violet-red, natural food grade pigments with health benefits; however, their stability limits its use in industrial food processing. This can be overcome by placing the betalains in lecithin nanoliposomes (NLs), which causes a 76% improvement of betalain colour and stability. Extended sonication time (8 min) lowered the zeta potential (-47.5 to -40.8), and particle size (74.23 to 55.35 nm). Zeta potential, particle size, and polydispersity index of Betalain NLs (BNLs) didn't change significantly during storage (40 days). Degradation in the colour of BNLs was observed only at 121 °C (20 min) while the native juice degraded at 100 °C (20 min). BNLs were incorporated in gummy candies (GuCa) to improve its colour stability. The betalain retention, colour, texture, antioxidant activity, and shelf-life of the GuCa during storage (5 °C, 28 days) demonstrated the efficacy of BNLs to be explored as a natural colourant for the food industry.

The Colors of Health: Chemistry, Bioactivity, and Market Demand for Colorful Foods and Natural Food Sources of Colorants

There is an increasing consumer demand for natural colors in foods. However, there is a limited number of available natural food sources for use by the food industry because of technical and regulatory limitations. Natural colors are less stable and have less vibrant hues compared to their synthetic color counterparts. Natural pigments also have known health benefits that are seldom leveraged by the food industry. Betalains, carotenoids, phycocyanins, and anthocyanins are major food colorants used in the food industry that have documented biological effects, particularly in the prevention and management of chronic diseases such as diabetes, obesity, and cardiovascular disease. The color industry needs new sources of stable, functional, and safe natural food colorants. New opportunities include sourcing new colors from microbial sources and via the use of genetic biotechnology. In all cases, there is an imperative need for toxicological evaluation to pave the way for their regulatory approval.

RNA-sequencing analysis reveals betalains metabolism in the leaf of Amaranthus tricolor L

Amaranth plants contain large amounts of betalains, including betaxanthins and betacyanins. Amaranthin is a betacyanin, and its molecular structure and associated metabolic pathway differ from those of betanin in beet plants. The chlorophyll, carotenoid, betalain, and flavonoid contents in amaranth leaves were analyzed. The abundance of betalain, betacyanin, and betaxanthin was 2-5-fold higher in the red leaf sectors than in the green leaf sectors. Moreover, a transcriptome database was constructed for the red and green sectors of amaranth leaves harvested from 30-day-old seedlings. 22 unigenes were selected to analyze the expression profiles in the two leaf sectors. The RNA-sequencing data indicated that many unigenes are involved in betalain metabolic pathways. The potential relationships between diverse metabolic pathways and betalain metabolism were analyzed. The validation of the expression of 22 selected unigenes in a qRT-PCR assay revealed the genes that were differentially expressed in the two leaf sectors. Betalains were biosynthesized in specific tissues of the red sectors of amaranth leaves. Almost all of the genes related to betalain metabolism were identified in the transcriptome database, and the expression profiles were different between the red sectors and green sectors in the leaf. Amaranth plants consist of diverse metabolic pathways, and the betalain metabolic pathway is linked to a group of other metabolic pathways.

Influence of extraction parameters and stability of betacyanins extracted from red amaranth during storage

Natural colorants are important alternatives to synthetic colorants. They are considered harmless and positively affect biological activities owing to their antioxidant potential. The present study deals with the assessment of the extraction processes and the effects of pH (1.0, 3.0, and 5.0), extraction media (water and 50% ethanol) and storage condition (ambient and refrigeration) on betacyanin content, color values, as well as degradation kinetics of total betacyanins in red amaranth. Betacyanin content was more stable at higher than at lower pH. The degradation rate constant (K) was higher and the half-life (t_1/2) was lower at ambient temperature compared to refrigeration temperature. Betacyanin degradation was higher at ambient temperature (30 ± 2 °C) than at refrigeration temperature (4 °C). The pH, storage time, and temperature affected the stability of the color attributes. Therefore, this work suggests that water and lower temperature (4 °C) could be applied to extract more betacyanins from red amaranth and betacyanins might be used as an alternative to synthetic color.

Conical intersections and the weak fluorescence of betalains

Betalains are natural plant pigments found in certain plants belonging to the order Caryophyllales.

Microbial maceration: a sustainable approach for phytochemical extraction

A rapid change in the lifestyle has witnessed poor health with the increased incidences of numerous diseases in the recent years, and ultimately increasing the demand of nutritious foods containing phytochemicals. A wide range of phytochemicals (secondary metabolites) is being synthesized in plants, which influence the human health upon consumption as dietary component. Recently, a number of the technologies (conventional and non-conventional methods) have been standardized by the different researchers for the extraction of these phytochemicals depending upon the raw material. However, selection of extraction method for commercial use depends upon various factors such as extraction efficiency, time required, and cost of operation. Considering these factors, microbial maceration is one of the viable approaches which is easy to handle, cost-effective, energy efficient, less hazardous and having high extraction rate. Recently, researchers have utilized this technique for the maceration of different plant-based substrates (such as legumes, cereals, pulses, fruits and vegetables) and their respective wastes for the efficient extraction of numerous phytochemicals with increased efficiency. However, scale up studies and analysis of toxic compounds produced by microbes are still a lacking field and need to be explored further by the researchers and industrialists to bring it into reality. Therefore, the present review aims to document the recent findings related to microbial maceration in a crisp way to provide the complete information to the readers.

Identification and characterization of bioactive phenolic constituents, anti-proliferative, and anti-angiogenic activity of stem extracts of Basella alba and rubra

Basella is an important green leafy vegetable species of Chenopodiaceae family and is known for its medicinal properties. Hydroxy-benzoic acids, hydroxy-cinnamic acids and flavones groups were identified and characterized from the aqueous stem extracts of B. alba and B. rubra species. Higher values of phenolics as well as antioxidant activity were noted from B. alba species extracts. The evaluation of the cytoxicity of these extracts on A431 (epidermoid carcinoma), Hep G2 (hepatocellular carcinoma) and MG 63 (osteosarcoma) cells indicated anti-proliferative activity against all the cell lines. B. alba extract showed higher anti-proliferative activity (37.95-84.86%). Chick embryo chorioallantoic membrane (CAM) assay revealed inhibition of neo-vessels formation. Significant suppression was found with extracts of B. alba at 7 mg/ml compared to that of B. rubra. This is the first study to report the anti-angiogenic activity of Basella species. These studies indicate that Basella sps can be used as a source of natural antioxidants and can be of high significance in pharmaceutical and nutraceutical industries.

Thermal Degradation of Major Gomphrenin Pigments in the Fruit Juice of Basella alba L. (Malabar Spinach)

Generation of decarboxylated and dehydrogenated gomphrenins during heating of Basella alba L. fruit juice containing high levels of betacyanin pigments was monitored by LC-DAD-ESI-MS/MS. The presence of principal decarboxylation products, 2-, 17-, and 2,17-decarboxy-gomphrenins, their diastereomers, as well as minor levels of their dehydrogenated derivatives are reported. In addition, determination of molecular masses of decarboxylated gomphrenins by high-resolution mass spectrometry (LCMS-IT-TOF) was performed. Enzymatic deglucosylation of decarboxylated and dehydrogenated gomphrenins resulted in the generation of betanidin diagnostic derivatives for further identification processes. In addition, experiments were conducted to prove that the position of glucosylation of the chromophoric part of betacyanins (betanidin part) has decisive influence on different chromatographic properties of their decarboxylated derivatives.

Coloring attributes of betalains: a key emphasis on stability and future applications

Organoleptic characteristics largely determine food acceptance, selection, and subsequent consumption.

Phytoconstituents and stability of betalains in fruit extracts of Malabar spinach (Basella rubra L.)

This study aimed to assess the nutrient composition, minerals, and stability of betalains pigment from fruit extracts of Basella rubra. The proximate composition included total carbohydrates (1.64 g), protein (51 mg), total lipid (1.38%), moisture (81.76%), niacin (0.5 mg), ascorbic acid (89.33 mg), and total tocopherols (1.27 mg) in 100 g fresh deseeded fruit. Total dietary fibre of 32.52 g and soluble dietary fibre of 12.34 g in 100 g dry deseeded fruits. Fatty acid composition of dry deseeded fruits comprised 57.52% SFA, 20.62% MUFA and 22.28% PUFA. Pigment (betalain) rich fruit extracts showed excellent stability over 20 days of storage under varied pH, temperature, light, acids, salts and sugars. B. rubra fruit was observed as a potential source of nutrients and betalains as a functional food.

Emerging technique for healthier frying for production of reduced-fat beetroot (Beta vulgaris) chips

In the present work, the processing variables were optimized to retain betalain compound and their effect on quality attributes (oil content, breaking force and color) of fried beetroot chips. The beetroot slices were fried in lab scale vacuum fryer. Experimental design with temperature (86-153 °C), absolute pressure (1.3-9.7 kPa) and frying time (2.6-9.4 min) as independent variables which produced 20 different combinations, were studied using response surface methodology to study the effect of these variables on product responses. Multiple regression equations were obtained to describe the effects of each variable on product responses. Results predicted that optimum frying conditions namely temperature ranging from 101 to 110 °C, pressure ranging from 2.9 to 4.4 kPa and time 6.0 min required for preparing beetroot chips with oil content (Y₁) ≤ 15.7, breaking force (Y₂) ≤ 11.53, L* value (Y₃) ≥ 27.94, a* value (Y₄) ≤ 17.87, b* value (Y₅) ≥ 6.46, betalain content (Y₆) ≥ 13.05 (mg/l) and overall acceptability (Y₇) ≥ 7.5. Further results showed that traditionally fried beetroot chips contain 2.6 mg/l betalain, 19.68 N breaking force, 21.1 L*, 15.18 a*, 2.38 b*, overall acceptability 6.0 and 38.41 % oil content.

Impact of extraction and processing conditions on betalains and comparison of properties with anthocyanins - A current review

The search for natural pigments has been driven by growing evidence indicating that synthetic colorants can cause deleterious health effects. Betalains, in addition to anthocyanins, have been proposed as an alternative to address this need. However, the incorporation of natural pigments poses some challenges to the food industry, such as reduced stability in comparison to their synthetic counterparts. Moreover, betalains are not well studied in comparison to anthocyanins and information about the effects of processing on their physicochemical properties and stability is scattered. Thus, this review will provide an overview of the recent research on the extraction and processing of betalains from natural sources, and comparison of their colorant and physicochemical properties with anthocyanins.