Stability Of Betalains Research Articles

Degradation kinetics of betalains in red beetroot juices throughout fermentation process and storage

Contemporary customers have increasingly heightened demands regarding their dietary preferences, favoring readily available and healthful ready-to-consume food and beverage alternatives. In order to fulfill this demand, the beverage industry has been exploring innovative products. Red beetroot juice (RBJ) is easily consumed and offers a beneficial advantage due to its betalain content. Both the traditional/spontaneous method and the industrial method are viable options for producing RBJ. The aim of this study was to examine the stability of betalains, the primary bioactive component in RBJ, throughout the fermentation process and during storage. The RBJ samples contained betalain pigments, as indicated by the infrared spectra. No decrease in betalain content was observed in either RBJ juice fermented by two different methods. The total betalain content of the RBJ samples was 594.068 and 535.152 mg/L at the beginning of fermentation through the spontaneous method and the method with the addition of Lacticaseibacillus paracasei 431 (Lc. paracasei), respectively, and 580.151 mg/L and 667.382 mg/L at the conclusion of fermentation, respectively. Mathematical models were employed to represent the degradation of betalains over time during storage. It was found that the sigmoidal model (R2 = 0.974) and other models (R2 = 0.957–0.969) demonstrated a greater potential to describe the degradation of betalains in RBJ samples produced by the spontaneous method compared to the first-order kinetics model (R2 = 0.932). The models used in the study were successful, with R2 values ranging between 0.927 and 0.932 in the RBJ samples produced with the addition of the probiotic Lc. paracasei for predicting betalain degradation.

Effects of potato extract on betalains, antioxidant activity, and sensory preference in buttermilk through fermentation with Lactobacillus acidophilus and Streptococcus salivarius

Utilizing flavorings in drinks enhances aroma, preserves natural properties, and poses challenges in production costs and crop demands. Mitigating these challenges is possible by employing waste products like potato skins. This investigation aims to explore the potential of dried mint-flavored stirred Buttermilk enriched with harvested potato water extract (HPE) for improved functionality and acceptability. To achieve this objective, the betalains, antioxidant, and antimicrobial activities were examined at pH 4.5 and 5.5, along with the phenolic and flavonoid content. Following that, HPE was incorporated at different concentrations of 3 % (T1), 5 % (T2), and 7 % (T3) to assess the stability of betalains, the physicochemical properties, the nutritional value, and the lactic acid bacteria (LAB) content during storage (for 0, 7, 14, and 21 days at 5 °C).In comparison to the control group (0 % HPE), the inclusion of HPE remarkably (p < 0.05) reduced the pH, increased total acidity, total LAB, vitamin C, antioxidant activity, and sensory preference. Total LAB increased from 5.25 – 5.79 CFU/mL and reached its peak at 7 %HPE addition, ranging between 5.76 – 6.28 CFU/mL. Vitamin C content increased from 4.78 mg/100 g to 5.27 mg/100 g, and after 21 days, it declined to the level of the control group, ranging between 3.14 mg/100 g. HPE at 5 % concentration resulted in a more stable vitamin C content during the 21-day storage period. HPE exhibited significant quantities of betalains (478.42 mg/L), phenolics (156.44 mg/g), and flavonoids (51.23 mg/g), showcasing elevated levels of Caffeic acid and p-coumaric acid. The stability of betalains at pH 4.5 was superior to that at pH 5.5 following a 21-day storage period (332.21 and 253.22 mg/L, respectively). The application of HPE led to the development of a functional drink boasting elevated phenolic content (90.02 ± 2.05 mg/g) and flavonoids (65.21 ± 1.33 mg/g) in the presence of 7 %HPE, as compared to the control (78.91 ± 2.55 and 59.32 ± 1.46 mg/g, respectively). The drinks demonstrated notable DPPH inhibitory activity (69.31 ± 1.1) in comparison to the control (85.52 ± 1.33 µL/mL). In conclusion, the addition of HPE can enhance the stability of sensory properties in buttermilk and improve its acceptability.

PH-dependent stability of major betalains in the encapsulated beetroot extracts (Beta vulgaris L.).

Betalain is a water-soluble pigment contained in Caryophyllales plants. It not only holds potential as a natural food colorant but also offers various health benefits, acting as an antioxidant. This study focused on analyzing the pH-dependent stability of encapsulated betalain pigments extracted from red beetroot (Beta vulgaris L.) using methods such as absorption spectroscopy, HPLC, and LC-MS. The major pigments identified were vulgaxanthin I, betanin, isobetanin, and neobetanin, alongside minor components, including three betaxanthin species and a degradation product known as betalamic acid. Spectrophotometric analyses revealed that above pH 8, the betalain peak at 435nm decreased and red-shifted to a peak at 549nm, a shift that could be reversed through neutral pH treatment. At pH 11, a new broad peak appeared at 410nm and was identified as betalamic acid. To assess the pH-dependency of each betalain, the targeted betalains were separated and quantified through HPLC after incubation across a wide pH range of 2-11 and during storage. After 3 days of storage in highly alkaline conditions (pH 10-11), major betalains, with the exception of neobetanin, underwent significant degradation. Conversely, these pigments displayed relative stability in acidic conditions. In contrast, neobetanin showed vulnerability to acidic conditions but exhibited tolerance to alkaline pH levels of 10-11. The degradation product, betalamic acid, demonstrated a similar susceptibility to alkaline pH as betanins. In conclusion, the significant stability decrease under highly alkaline conditions results not only from the hydrolytic reaction of betalains but also from the degradation of betalamic acid itself. PRACTICAL APPLICATION: Encapsulation methods are used to enhance the stability of betalains against temperature variations; however, the effects of pH, especially when considering individual betalain species, are not well understood. Despite betalains exhibiting similar features and being suitable for a wide pH range from acid to alkaline conditions, they are significantly affected by alkaline pH levels exceeding 10, as well as by storage duration. This study demonstrated the application of encapsulation to pH-dependent stability, and the findings offer valuable insights and a fresh perspective on betalains as red biocolorants, extending their potential application to a wide range of pH-controlled food products.

Beetroot Stalk Extract as a Functional Colorant for Stirred Yogurt Beverages: Effect on Nutritional Value and Stability during Storage

Betalains are natural red colorants characterized by their stability to anthocyanins, particularly in acidic foods. Beetroot stalks are a good source of betalains, with higher bioactive components than the whole root. Hence, the current study aims to investigate the potential use of beetroot stalk water extract (BSE) as a functional colorant for raspberry-flavored stirred yogurt. For this purpose, the betalains of BSE and their stability at pH 4 and 5 were investigated in addition to the phenolic and flavonoid content. Furthermore, the antioxidant and antimicrobial activities of BSE were characterized. Subsequently, BSE was added to raspberry-flavored stirred yogurt at concentrations of 1 (T1), 2 (T2), and 5% (T3) to study the stability of betalains, the physicochemical properties, the nutritional value, and the viability of lactic acid bacteria during storage (14 days/4 °C). BSE showed a considerable amount of betalains (456.82 mg/L) and phenolics (139.87 mg/g), with a high content of chlorogenic and ferulic acids. The betalains showed greater stability at pH 4 than pH 5 after 14 days of cold storage (275.05 and 247.00 mg/L, respectively). Applying BSE resulted in a functional beverage with high phenolic content (116.55 ± 1.23 mg/g) and flavonoids (71.77 ± 0.57 mg/g) in T3 (5%) compared to the control (95.11 ± 1.12 and 64.72 ± 0.29 mg/g, respectively). The beverages shared high DPPH scavenging activity (IC50 = 71.68 ± 1.30– 69.18 ± 0.48) compared with the control (78.47 ± 3.27 µL/mL). BSE significantly increased the betalain level in yogurt from 44.19 ± 0.05 mg/L to 67.86 ± 0.54 mg/L, resulting in pale red beverages with a redness value of 6.38–9.68 on day 1. By day 14, the redness of the treatments decreased by 6–18% compared with the first day, reaching 5.25 ± 0.03 (T1), 7.87 ± 0.03 (T2), and 8.43 ± 0.05 (T3) due to the degradation of betalains. Generally, BSE is a promising natural colorant when added to stirred yogurt, and it has preferable physical and sensory properties, as it improves the stability of the red color throughout cold storage and increases the nutritional quality. The use of beet stalks as a natural and functional colorant is presented for the first time in the current investigation.

Simple and efficient protocol for amaranth betalains extraction and stability analysis by ATR-FTIR spectroscopy

Betalains are pigments highly appreciated in the food industry for their applications for human consumption and for their different contributions to human health. However, the stability of betalains is compromised by several factors, including temperature and pH, so it is necessary to determine the optimal conditions to maintain the betalains stability in the final product. In this study, different protocols for extracting betalains from amaranth are compared, and Attenuated Total Reflectance-Fourier Transformation Spectroscopy (ATR-FTIR) together with principal component analysis (PCA) is used to determine amaranth pigments stability at different temperatures and pHs. A simple and efficient method to extract betalains from amaranth plants was established. It was possible to know the stability of amaranth betalains under different temperatures and pH conditions using ATR-FTIR and UV/Vis spectroscopy. The bands associated with carboxylic acids, amino groups, carbon dioxide and carbon double bonds detected by ATR-FTIR spectroscopy were related to the state of conservation and degradation of betalains. Our results will improve the storage, supervision and application of betalains in the food industry.

Production of betalain-rich Opuntia ficus-indica peel flour microparticles using spray-dryer: A holist approach

This study aimed to obtain a betalain-rich extract (BRE) from Opuntia ficus-indica peels and protect them through a holistic approach involving microencapsulation via spray-drying. To enhance the stability of the microencapsulated betalains, an antioxidant-rich extract (ARE) obtained through hydrothermal extraction from the residual material remaining after the conventional extraction of betalains was used as a stabilizer during the spray-drying process. The antioxidant activity of the ARE was evaluated by measuring its IC50 value for 2,2-Diphenyl-1-picrylhydrazyl (DPPH) of 65.8 μg/mL, its Trolox equivalent antioxidant capacity (TEAC) of 60.4 gTrolox eq./100 g, and its reducing power of 16.6 g butylated hydroxytoluene (BHT) eq./100 g. Spray-drying parameters were optimized using a Box-Behnken design to enhance the total betalain content and minimize by-product formation. The results demonstrated that the addition of the ARE significantly improved the stability of betalains during spray-drying, leading to the formation of microparticles with high betalain content and enhanced stability. The optimal conditions (0.72% starch, 1.50% BRE and 0.25% ARE) resulted in microparticles with a maximum concentration of 6.74 ± 0.09 mgBetalains/g. The predictive model exhibited high accuracy in estimating experimental values. This research provides a natural and sustainable solution for food coloring by effectively utilizing discarded Opuntia ficus-indica peel. Moreover, it offers new scientific understanding on the production of betalain-rich microparticles as a possible substitute for food coloring, with considerable benefits in terms of sustainability and high antioxidant capacity.

Optimization of ionic gelling encapsulation of red beet (Beta vulgaris L.) juice concentrate and stability of betalains

Red beet (Beta vulgaris L.) with high betalain compounds possesses antioxidant properties beneficial in human's health and is a substitute to artificial colorants in the food industry. But the stability of the natural pigments should be concerned therefore encapsulation is a promising tool to overcome the saturation problem of the color. One of the encapsulation methods which is alginate/calcium-chloride ionic gellation was applied to beet juice concentrate (70 °Brix). Optimum conditions for encapsulation were determined by Response Surface Methodology, Box-Behnken Design where the red beet concentration was found as 14.81% sodium-alginate concentration as 1.7%, and dipping time as 5 min. The effects of the 6 weeks of storage at 25 ± 1 °C were also investigated. During the 6 weeks of storage, a* value of capsules has decreased gradually. Starting from the 4th week, changes in betalain content were found statistically insignificant (p > 0.05). At the end of the storage period, 79.48% of the betalain was preserved. Additionally, the characterization of capsules was maintained by scanning electron microscope (SEM) images, total dry matter, total phenolic content, antioxidant capacity, release test for characterization of capsules, potential usage in model food, and sensory analysis were examined and evaluated. These results showed that ionic gelation is a promising method to obtain stable betalain capsules that have the potential to be used as a natural colorant.

Dynamics of changes in the content of betalain pigments in red beet roots during the growing season and storage

Purpose. Betalains, plant pigments of red beet roots, exhibit antioxidant activity and reduce the risks of many pathological conditions. However, the widespread introduction of betalains is hampered by insufficient knowledge of their transformations during the growing season and storage of root crops, which was the purpose of the work.Methods. Root crops of five varieties of table beets were used in the studies. The content and stability of betalains were determined by spectrophotometric methods according to the numerical indices of the absorption spectra of extracts from root crops.Results. In the beet roots in the first 20 days of vegetation after germination, the content of betaxanthines is higher than that of betacyanins, but by the 40th day, betacyanins exceed betacyanins over betaxanthin in the ratio of 1.26-2.21. By the 70th 90th days of vegetation, the main pool of betalains is formed, their content reaches 84.5-198.6 mg / 100 g, the ratio of betacyanins / betaxanthins and resistance are 2.47-9.76 and 0.82-0.91 respectively. The highest excess of the content of betacyanins over betaxanthins by 8.11 9.65 times was obtained in beet root crops of Creolka and Veselaia Smulyanka varieties. The stability of betalains during six-month storage decreases less than 1.4 times.Conclusion. It is advisable to use the developed spectrophotometric method for determining the stability of betalains in the express analysis of beet root crops. Betalains are more stable than other plant antioxidants. Beet roots are more preferred for fortifying diets than other foods with antioxidant activity.

Oil-Based Double Emulsion Microcarriers for Enhanced Stability and Bioaccessibility of Betalains and Phenolic Compounds from Opuntia stricta var. dillenii Green Extracts.

Opuntia cactus fruit (prickly pear flesh and agricultural residues such as peels and stalks) is an important source of bioactive compounds, including betalains and phenolic compounds. In this work, two double emulsion W1/O/W2 formulations (A and B) were designed to encapsulate green extracts rich in betalains and phenolic compounds obtained from Opuntia stricta var. dillenii (OPD) fruits with the aim of improving their stability and protecting them during the in vitro gastrointestinal digestion process. In addition, the characterization of the double emulsions was studied by microscopy and the evaluation of their physical and physico-chemical parameters. Formulation A, based on Tween 20, showed smaller droplets (1.75 µm) and a higher physical stability than Formulation B, which was achieved with sodium caseinate (29.03 µm). Regarding the encapsulation efficiency of the individual bioactives, betalains showed the highest values (73.7 ± 6.7 to 96.9 ± 3.3%), followed by flavonoids (68.2 ± 5.9 to 95.9 ± 7.7%) and piscidic acid (71 ± 1.3 to 70.2 ± 5.7%) depending on the formulation and the bioactive compound. In vitro digestive stability and bioaccessibility of the individual bioactives increased when extracts were encapsulated for both formulations (67.1 to 253.1%) in comparison with the non-encapsulated ones (30.1 to 64.3%), except for neobetanin. Both formulations could be considered as appropriate microcarrier systems for green OPD extracts, especially formulation A. Further studies need to be conducted about the incorporation of these formulations to develop healthier foods.

Chemical characterization of yellow-orange and purple varieties of Opuntia ficus-indica fruits and thermal stability of their betalains.

Betalains are plant pigments with biological properties and can be used instead of synthetic colorants to confer color and functional properties to foods. The objective of this work was to carry out the chemical characterization of two varieties of prickly pear of Opuntia ficus-indica, one of yellow-orange coloration (Mandarina) and the other of purple coloration (Vigor), through measurements of chemical parameters and color in pulp, antioxidant activity, total phenolic compounds, and betalain content. Considering the thermolability of betalains and their potential applications in food, the thermal stability and activation energy of betacyanins from Vigor variety and betaxanthins from the Mandarina variety were also evaluated and compared with those from beetroot, the main source of betalains. Results for chemical characterization agreed with previous prickly pear reports of other regions, while the thermal degradation kinetics of betalains showed a first-order degradation pattern with respect to time and temperature treatment. Betacyanins from Vigor prickly pear showed similar thermal stability to those from beetroot, which was reflected in similar values of activation energy, while betaxanthins from Mandarina prickly pear showed a higher stability, and therefore a higher activation energy, than those from beetroot. Based on the results, the prickly pear varieties used in this study can be considered as a good source of betalains with potential applications in food and, in addition, the methodology for the evaluation of thermostability can be used to compare the stability of betalains from different sources in a temperature range of 50-90°C. PRACTICAL APPLICATION: The varieties of prickly pear used in this study can be considered a good source of red-purple and yellow-orange easily extractable pigments. In addition, we report a methodology that can be used for the evaluation of the thermal stability of these pigments and to compare this stability between different plant sources. Gaining knowledge on betalain thermal stability will make it possible to propose specific applications, for example, in processed foods requiring different pigment stabilities.

Microencapsulation of red beet extract using chitosan‐Persian gum complex coacervates

The coacervation technique is an efficient encapsulation process in which macromolecules with opposite surface charges interact, resulting in polymeric complexes. Hydroethanolic solvent (52%) was selected to obtain bioactive compounds from red beet using the mixture experimental design. Red beet extract was encapsulated in a complex of chitosan and negatively charged Persian gum. The optimum condition for coacervate formation was received at the chitosan to Persian gum ratio of 18:82 at pH 5.3. The coacervation yield of the two polysaccharides was 80%, and the zeta potential of dispersion was close to zero. Complex formation between two biopolymers was confirmed through FTIR. Micro-sized coacervates showed 90% encapsulation efficiency for the betalain extract to coacervate dispersion ratio of 14.3%. The betalain-loaded chitosan/Persian gum complex presented superior thermal stability compared with pure polysaccharides. The obtained complex can be applied to improve the stability of betalains and control their release in food and pharmaceutical applications. Novelty Impact Statement Equal mixture of water:ethanol resulted in maximum betalain extraction. Strong electrostatic complexation was approved between Persian gum and chitosan. Persian gum/chitosan coacervate demonstrated high loading capacity for betalains.

Extraction and stability of betalains extracted from beetroot tubers and the fruit of eight cactus pear cultivars

ISHS X International Congress on Cactus Pear and Cochineal: Cactus - the New Green Revolution in Drylands Extraction and stability of betalains extracted from beetroot tubers and the fruit of eight cactus pear cultivars

Beetroot's crude aqueous extract photosensitizer-Formic acid-Sodium Lauryl Sulphate photogalvanic electrolyte: Solar power and storage

Crude aqueous extract of Beetroot has been used as a natural photo-sensitizer for photogalvanic solar power and storage. Beet's root extract-based photogalvanic cell shows improved electrical performance (power 674.4 μW, efficiency 15.31%) and follow the same principles as followed by synthetic photo-sensitizers based photogalvanics. Betalains have been characterized as the main light-absorbing molecules present in the extract. The concentrations and photo-thermal stability of Betalains have been studied for their future perspective. The estimated ground state and excited state potential values (vs NHE) of Betalain are as 0.9015 V and 1.3565 V, respectively, and it matches the published data. On the basis of standard reduction potential and electrochemical series, it is established that the reductant donates an electron to the excited state of pigment, and ground-state Betalain pigment donates an electron to the reductant. The same pattern of electron transfer is also reported for earlier photogalvanics.

Stability enhancement of beetroot betalains through copigmentation.

Like other natural pigments, betalains have a stability problem. Copigmentation can be explored to address this issue. In this study, black carrot anthocyanins were used for the first time as copigment with betalains so that copigmented betalains with enhanced stability could be developed to withstand deteriorative processing and storage conditions. Increase in hyperchromic and bathochromic shift with subsequent increase in black carrot anthocyanin extract (0.250 g L-1 ) addition from 0.2 to 1.0mL L-1 was observed in native betalain pigments from 0.28 to 1.90 and 538 nm to 564 nm, respectively. For maximum recorded bathochromic shift, 0.8mL L-1 addition of copigment was optimized. Copigmented betalain pigment showed better stability in comparison with native pigment, when exposed to light, temperature more than 60 °C and ≥1.0g L-1 NaCl. At constant incubation time (3h), copigmented betalains degraded up to 20.79-41.43% whereas the non-copigmented counterpart degraded up to 83.49-86.86% at 60, 75 and 90 °C, respectively. Lower rate constant (k) and enhanced activation energy (Ea ) showed higher thermostability of copigmented betalains. With constant light exposure, the half-life value of betalains was 145.2h, which increased approximately twofold (274.08 h) after copigmentation. The t1/2 of betalain pigment at 10%, 15% and 18% salt addition was 81.12, 75.36 and 83.52 h, which increased to 186.96, 226.56 and 152.88 h after copigmentation. These findings support that black carrot anthocyanin is a potential and compatible copigment for water-soluble betalain pigment that enhances stability of betalains under extreme processing conditions. © 2022 Society of Chemical Industry.

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

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.

Improvement of betalains stability extracted from red dragon fruit peel by ultrasound-assisted microencapsulation with maltodextrin

Natural betalains can be potential food additives because of their antioxidant activities, but they have poor thermal stability. In this study, betalains were extracted from red dragon fruit peel, and then encapsulated with maltodextrin by ultrasound method to increase the physicochemical properties of betalains microcapsules. The encapsulation efficiency of the betalains was above 79%, and the particle size and Zeta potential values were 275.46 nm and −29.01 mV, respectively. Compared to the control sample, onset temperature and DPPH free radical scavenging of betalains microcapsules under the modest ultrasound treatment (200 W, 5 min) was increased by 1.6 °C and 12.24%, respectively. This increase could be due to the ability of ultrasonification to create interactions between maltodextrin and betalains (as evidenced by FT-IR). Therefore, modest ultrasound treatment can be used for microcapsulation to improve the stability of betalains, and then expand the application of betalains in heat processed food field.

Extraction and Stabilization of Betalains from Beetroot (Beta vulgaris) Wastes Using Deep Eutectic Solvents.

Deep eutectic solvents (DES) using magnesium chloride hexahydrate [MgCl2·6H2O] and urea [U] proportions (1:1) and (2:1), were prepared for their use as extracting and stabilizer agents for red and violet betalains from beetroot (Beta vulgaris) waste. The synthetized DES [MgCl2·6H2O] [U] showed similar properties to eutectic mixtures, such as, liquid phase, low melting points and conductivity, thermal stability, and variable viscosity. In turn, betalain DES extracts (2:1) exhibited compatibility in the extraction and recovery of betalains from beetroot wastes, showing a betalain content comparable to that of betalain extracts. Betalain stability was determined by degradation tests; the exposure conditions were visible light (12 h), molecular oxygen from atmospheric air and environmental temperature (20–27 °C) for 40 days. The kinetic curves of the betalain degradation of water samples depicted a first-order model, indicating the alteration of a violet colouration of betalains from beetroot waste for 5–7 days. However, betalains from DES extracts were kept under visible light for 150 days, and for 340 days in storage (amber vessels), achieving a stability of 75% in comparison with initial beet extracts.

Emerging technology approach for extractability and stability of betalains from the peel of beetroot (Beta vulgaris L.)

AbstractBetalains are natural color compounds with high water affinity, unstable, and fragile; hence, understanding their thermal tolerance is always beneficial either in manufacturing them or in their application in betalain-rich functional foods for better handling. In our study, the extractability of betalains via microwave-assisted extraction (MAE) from the peel of beetroot was implemented at 100–800 W for 30–150 s with four different solvents. Among the maximum amounts of total betalains (202.08 ± 2.23 mg/100 g FW), betacyanin (115.89 ± 1.08 mg/100 g FW) and betaxanthin (86.21 ± 1.16 mg/100 g FW) were generated by pure water solvent after 150 s of MAE at 800 W. Alternatively, the susceptibility of beetroot peel extracts to processing conditions was investigated by heating them at 30–70 °C, and the thermal instability of betalains was evaluated by half-life (t1/2), temperature quotient (Q10), and activation energy (Ea), using the Arrhenius equation. The resulted retention percentage (R%) proved that ascorbic acid improved the R% of total betalains from 22 to 51% and betacyanin from 3 to 29% and in contrast reduced R% of betaxanthin from 56 to 40% after the heat treatment at 70 °C for 5 h.

Bioaccessibility of Antioxidants in Prickly Pear Fruits Treated with High Hydrostatic Pressure: An Application for Healthier Foods.

High hydrostatic pressure (HHP) is a commercial processing technology which can enhance the health potential of foods by improving the bioaccessibility of their bioactive compounds. Our aim was to study the bioaccessibility and digestive stability of phenolic compounds and betalains in prickly pear fruits (Opuntia ficus-indica L. Mill. var. Pelota and Sanguinos) treated with HHP (100, 350, and 600 MPa; come-up time and 5 min). The effects of HHP on pulps (edible fraction) and peels (sources of potential healthy ingredients) were assessed. In pulps, betanin bioaccessibility increased (+47% to +64%) when treated at 350 MPa/5 min. In HHP-treated pulps, increases in the bioaccessibility of piscidic acid (+67% to +176%) and 4-hydroxybenzoic acid glycoside (+126% to 136%) were also observed. Isorhamnetin glycosides in peels treated at 600 MPa/CUT had higher bioaccessibility (+17% to +126%) than their controls. The effects of HHP on the bioaccessibility of health-promoting compounds are not exclusively governed by extractability increases of antioxidants in the food matrix (direct effects). In this work we found evidence that indirect effects (effects on the food matrix) could also play a role in the increased bioaccessibility of antioxidants in fruits treated with HHP.

Red beetroot: Health benefits, production techniques, and quality maintaining for food industry

Red beetroot and its functional products have gained popularity in the food industry and are utilized as a food colorant or additive. Red beetroots are a great source of unique bioactive components called betalains and are rich in polyphenols, antioxidants, vitamins, carotenoids, flavonoids, minerals, and ascorbic acids. It has diverse therapeutic effects associated with biochemical content. However, maintaining health benefits is problematic due to its betalain instability. It is essential to choose the best cultivar with high betalain levels for ensuring the target product in the food industry. In addition, betalains are quite sensitive toward production techniques and pre and postharvest factors, which are the main indicators for affecting the food quality of red beetroot. Therefore, we aimed to review the results of some studies on red beetroot and provide a comprehensive knowledge on health benefits, production techniques, and quality maintenance for the food industry. Moreover, nutrition content, potential uses, and future outlook were also summarized. Practical applications The present review summarizes a comprehensive knowledge about pre and postharvest factors affecting quality of red beetroots and indicates ways to maintain high quality red beetroots for promising value-added products in respect of consumers and food processors. Moreover, recently reported processing techniques for red beetroots was examined and appropriate techniques were explained in order to sustain bioavailability and stability of betalains for food industry.