Blackberry Juice Research Articles

Metabolomic screening and urolithins metabotypes identification in the urinary metabolome of Costa Rican volunteers after blackberry (Rubus adenotrichos)-based drink consumption

BACKGROUND: Besides providing nutritional value, functional foods have potential beneficial effects on health. Consumers worldwide seek food products with added value based on physical and mental well-being. OBJECTIVE: This study aimed to analyze the urinary metabolome of volunteers who consumed a drink based on Costa Rican blackberries (Rubus adenotrichos) to identify the presence of urolithins and other possible bioactive compounds related to beneficial effects on health. METHODS: Fifteen healthy non-smoking male volunteers aged between 19 and 43 years old who consumed 250 ml of blackberry-based drink for breakfast for eight consecutive days were selected. Urine samples were obtained before and after drink consumption, which were submitted to analysis by Ultra-Performance Liquid Chromatography coupled to a Mass Detector (UPLC/ESI-Q-TOF-MS). Subsequently, a metabolomic analysis of the results was performed to identify the presence or absence of urolithins and other bioactive metabolites related to blackberry juice consumption. RESULTS: It was possible to detect high intensity presence of urolithin A (n = 6) and high intensity presence of both urolithin A and B (n = 5) in urine samples in several volunteers. However, finding them was impossible in others, or they were at very low intensities (n = 4). Likewise, it was possible to identify Menth-1-en-4,8 diol glucuronide and 1-O-E-Cinnamoyl-(6-arabinosylglucose) as other compounds related to the consumption of blackberries. CONCLUSIONS: The consumption of Costa Rican blackberries allowed us to demonstrate the presence of three metabotypes within the study population: 40% of strong urolithin A (UAP) producers, 33.3% of both urolithin (A and B) producers (UBP), and 26.7% of weak urolithin A producers (0P). Finally, it is recommended to carry out more research in this regard, considering a greater number of volunteers and including people of both sexes.

Blackberry Juice Fermented with Two Consortia of Lactic Acid Bacteria and Isolated Whey: Physicochemical and Antioxidant Properties during Storage.

Fermenting fruit juices with lactic acid bacteria (LAB) is a sustainable method to enhance fruit harvests and extend shelf life. This study focused on blackberries, rich in antioxidants with proven health benefits. In this research, we examined the effects of fermentation (48 h at 37 °C) at 28 days on whey-supplemented (WH, 1:1) blackberry juice (BJ) inoculated with two LAB mixtures. Consortium 1 (BJWH/C1) included Levilactobacillus brevis, Lactiplantibacillus plantarum, and Pediococcus acidilactici, while consortium 2 (BJWH/C2) comprised Lacticaseibacillus casei and Lacticaseibacillus rhamnosus. All of the strains were previously isolated from aguamiel, pulque, and fermented milk. Throughout fermentation and storage, several parameters were evaluated, including pH, lactic acid production, viscosity, stability, reducing sugars, color, total phenolic content, anthocyanins, and antioxidant capacity. Both consortia showed a significant increase in LAB count (29-38%) after 16 h. Sample BJWH/C2 demonstrated the best kinetic characteristics, with high regression coefficients (R2 = 0.97), indicating a strong relationship between lactic acid, pH, and fermentation/storage time. Despite some fluctuations during storage, the minimum LAB count remained at 9.8 log CFU/mL, and lactic acid content increased by 95%, with good storage stability. Notably, sample BJWH/C2 increased the total phenolic content during storage. These findings suggest that adding whey enhances biomass and preserves physicochemical properties during storage.

Study of the Pectinase Production from Soursop and Cherimoya Pulp for Agro-Industrial Waste Reduction in Colombia

Pectic enzymes are an eco-friendly alternative to improve extraction processes for the food industry. The objective of the research was to obtain pectinase from the pulp of soursop (Annona muricata L.) and cherimoya (Annona cherimola L.), as an alternative to reduce agro-industrial waste in Colombia; involving the study of the factors influencing the protein content of the enzymes extracted from different stages and types of fruits, the conditions for enzymatic activity, and the potential application in the food industry, particularly in extraction processes and juice clarification. A factorial design 23, spectrometric and potentiometric techniques evidenced that the protein content depends on factors such as fruit stage (suitable “s” and unsuitable “u” fruits for consumption) and fruit type (soursop and cherimoya). The higher protein content was obtained by the precipitation method in comparison to ion exchange chromatography. Cherimoya fruit presented a higher protein content of 326 ± 26 mg by precipitation, however, the soursop samples evidenced higher enzymatic activity, 2.2 ± 0.1 U/mL. The pectinase obtained was an acidic enzyme of type pectin methylesterase with an enzymatic activity of 27.0 ± 0.9 U/mL, under the optimal conditions of pH 4 and temperature of 40 °C. The application in blackberry juice evidenced a decrease in the absorbance and pH changes. From the current research, the pulp of soursop and cherimoya was proven as a cheap source to obtain pectinase with enzymatic activity for juice clarification, and this process is an alternative to reduce the negative impact on the environment and an economical source for the local producers.

Anti-Glioblastoma Potential and Phenolic Profile of Berry Juices

Glioblastoma is one of the most aggressive and lethal brain tumors. Due to the failure of conventional chemotherapies and targeted drugs pursuit of natural, less toxic agents is on the rise as well as their utilization in glioblastoma treatment. Consequently, this study explores the antiproliferative potential of selected berry juices (wild blackberry (Rubus discolor), dwarf elderberry (Sambucus ebulus), and raspberry (Rubus idaeus)) on glioblastoma cells (U87-MG and GBM43) in comparison to temozolomide. The juices were assessed for total phenolic content, proanthocyanins, polyphenol profiles, and antioxidant activity. Wild blackberry and dwarf elderberry juices exhibited higher total polyphenols, proanthocyanins, and monomeric anthocyanins compared to raspberry juice. HPLC analysis revealed distinctive anthocyanins, flavonoids, and phenolic acids in each juice. With the DPPH assay, the highest antioxidant potential had wild blackberry juice, while with other assays dwarf elderberry juice had the highest potential. Antiproliferative effects were dose-dependent, with wild blackberry juice demonstrating the highest potency, surpassing temozolomide in inhibiting GBM43 cell proliferation. In U87 cells, all juices exhibited antiproliferative effects, with wild blackberry showing the strongest impact. This study highlights the potential of wild blackberry juice as a potent natural agent against glioblastoma, suggesting its superiority over the conventional treatment.

The physicochemical properties and heat stability of milk fortified with blackberry juice and different casein-dominant ingredients

The influence of blackberry juice (BBJ) on the physicochemical properties and heat stability of skimmed milk with and without sodium caseinate or micellar casein concentrate (MCC) addition was investigated. This was performed by measuring the ionic calcium content, heat coagulation time, viscosity, particle size distribution and analytical centrifugation profiles of the different samples. BBJ decreased the ionic calcium of the samples, which resulted in a higher heat coagulation time at pH < 6.5. Its addition also prevented the increase in viscosity observed in skimmed milk and skimmed milk with MCC at pH 6.2 after heating. The particle size distribution, turbidity and analytical centrifugation profiles indicated this was due to a prevention of protein aggregation. In conclusion, the blackberry juice improved the heat stability of different types of milk systems in the pH range between 6.2 and 6.4, which was likely due to binding of calcium by blackberry polyphenols.

Augmenting Functional and Sensorial Quality Attributes of Kefir through Fortification with Encapsulated Blackberry Juice.

Kefir is a fermented dairy product claimed to confer many health-promoting effects, but its acidic taste is not appealing to some consumers. Therefore, the aim of this study was to enhance the functional and sensorial quality attributes of kefir through fortification with encapsulated blackberry juice (EBJ). The blackberry juice was successfully encapsulated via freeze-drying using lentil protein isolate (LPI) as the carrier. The encapsulated blackberry juice showed good physicochemical, functional, and morphological properties, as well as microbiological safety for use as a food additive. The kefir was fortified with EBJ in concentrations of 1, 2.5, 5, and 7.5% (w/w), stored for up to 28 days under refrigeration, and periodically evaluated. Parameters such as the viscosity, titrable acidity, and pH indicate that the kefir fortification did not affect its stability during storage. EBJ significantly increased the antioxidant properties of the kefir, depending on the fortification level. Additionally, all the fortified samples provided more anthocyanins than the daily recommended intake. Microbiological profiling demonstrated that good laboratory practice and hygiene were implemented during the experiments. Finally, the panelists showed that higher EBJ concentrations in the kefir resulted in greater overall acceptability, indicating that this encapsulate has the potential to be a substitute synthetic color additive in the dairy industry.

Effect of Blackberry Juice Consumption by Pregnant Rats on Brain Length and Cell Density of Dentate Gyrus in Male Wistar Pups.

The aim of this work was to evaluate the effect of blackberry juice consumption during pregnancy on the length of the brain, as well as on the cell density of the dentate gyrus in Wistar rat pups. Pregnant rats were divided into three groups: control (C), fed with standard diet and water ad libitum; BJ1, which received blackberry juice containing polyphenols (7.8 mg/kg) and anthocyanins (1.9 mg/kg); and BJ2, receiving blackberry juice containing polyphenols (9.3 mg/kg) and anthocyanins (3.54 mg/kg). On postnatal day 0, pups per litter, body weight, and length were measured, and cells in the dentate gyrus of male pups were quantified. Maternal body weight and pups per litter were statistically equal across experimental groups during pregnancy. Pups in BJ1 and BJ2 groups showed an increase in body weight (20%) and length (5%) when comparing to controls. An increase in brain length was observed in BJ2 group (8%) as compared to the control. A significant increase in the number of cells/mm2 was observed in the dentate gyrus of the offspring in BJ1 (21.8%) and BJ2 (23.7%) groups when compared to the control group. Given the above, blackberry juice may be considered a potential functional food during pregnancy, while further research on prenatal and postnatal development must be done.

Effect of anthocyanin-rich blackberry juice on endoplasmic reticulum stress in streptozotocin-induced diabetic rats

This study investigates blackberry juice’s effects on glucose metabolism, oxidative stress, inflammation, and endoplasmic reticulum stress (ER) in streptozotocin (STZ)-induced diabetic rats. Fifty Wistar rats were distributed to five groups randomly of ten rats each: Normal control, diabetic control, 9 mL/kg body weight (b.wt) blackberry juice only, blackberry juice plus diabetes, and 500 mg/kg b.wt metformin plus diabetes. A single intraperitoneal injection of 50 mg/kg b.wt STZ induced diabetes in the rats. This animal study continued for 56 days after the confirmation of diabetes. The levels of liver function and renal function, as well as insulin, glucose-6-phosphatase, glucokinase, and malondialdehyde (MDA) levels, and the activities of catalase (CAT) and superoxide dismutase (SOD), were determined. Additionally, interleukin-6 (IL-6) levels, tumor necrosis factor-alpha (TNF-α), and activated transcription factor 4 (ATF4) expressions were examined in the liver homogenate of rats. Furthermore, the liver tissues were utilized for histopathological examination. The results showed that blackberry juice prevented drastic loss of body weight and reduced food consumption in diabetic rats. Additionally, the levels of blood glucose, total protein, aspartate aminotransferase (AST), albumin, alanine aminotransferase (ALT), uric acid, creatinine, and urea improved after the administration of blackberry juice in diabetic rats. Blackberry juice significantly increased glucose metabolism and antioxidant status while reducing ER stress and inflammation in diabetic rats. Moreover, blackberry juice improved glucose metabolism by increasing insulin levels and improving the dysregulated activities of glucose-metabolizing enzymes. The microstructure of liver tissues in diabetic rats was also improved with blackberry juice treatment. Therefore, blackberry juice has the potential to alleviate diabetes in rats and could be considered as a functional food for people with diabetes.

Effects of thermosonication on ascorbic acid, polyphenols and antioxidant activity in blackberry juice

SummaryLimited research studies exist that assess the impact of thermosonication (TS) processing on antioxidant compounds in blackberry juice. Different combinations of TS parameters (temperature, amplitude power and time) were applied to blackberry juice using a pilot‐scale ultrasonic transducer (UIP500hdT). In low‐temperature treatment, the juice was treated at 10°C and 50% amplitude power for 5 min (10‐50‐5) showed the best retention of ascorbic acid (0.95 mg), total phenolic content (TPC) (459.55 mg GAE), 2, 2‐diphenyl‐1‐picrylhydrazyl (DPPH) (261.34 mg TE) and ferric reducing antioxidant power (FRAP) (604.09 mg TE). Similarly, in high‐temperature treatment, the juices were treated at 70°C and 100% amplitude power for 5 min (70‐100‐5) showed ascorbic acid (1.05 mg), TPC (166.17 mg GAE), DPPH (304.95 mg TE) and FRAP (686.93 mg TE). Both low‐ and high‐temperature treatments showed higher retentions in these attributes than untreated and pasteurised juices. The results were further supported by high retention of predominant polyphenols, namely cyanidin‐3‐O‐glucoside (400.58 and 336.94 mg/100 mL, for 10‐50‐5 and 70‐100‐5, respectively). A similar trend was observed in the contents of cyanidin‐3‐O‐rutinoside, procyanidin dimer B2, 5‐chlorogenic acid, epicatechin and rutin. TS treatment in overall could be a considerable alternative option to be used for antioxidant‐rich blackberry juice production as it has effects on phytochemicals similar to that of pasteurisation.

Solvent-free sonication of blackberries for the anthocyanin enrichment of juices obtained by pressing.

An ultrasound pretreatment was used to increase anthocyanins content in blackberry juice. Whole fruits were inserted into a glass vessel without contact with any solvent, sonicated in an ultrasonic bath, and then pressed with a manual juicer. The experimental design showed that 7 min at 65% of ultrasound amplitude increased the anthocyanin content in juices from 31 to 56% for BRS Xingu, Guarani, and Xavante cultivars. Two major anthocyanins, cyanidin-3-glucoside and cyanidin-3-rutinoside were found in higher concentrations for sonicated fruits. Therefore, ultrasonic pretreatment of whole fruits increased the anthocyanins in blackberry juices using a simple, fast, and green approach.

Encapsulation of phenolic compounds through the complex coacervation technique for the enrichment of diet chewable candies

The aim of this study was to encapsulate blackberry juice through complex coacervation, using carrageenan, tragacanth, and xanthan associated with pea protein as wall materials, in addition to characterizing the particles and evaluating the profile of release in vitro after its application in diet chewable candies with blended pulp of blackberry, butiá and red pitanga. The following analyses were performed: phenolic compounds, turbidimetry, encapsulation efficiency, antioxidant activity, morphology (SEM), functional groups (FTIR), thermal behavior (DSC), and in vitro digestion. The complex coacervation between pea protein/carrageenan, pea protein/tragacanth, and pea protein/xanthan particles occurred at pH 3.09, 4.61, and 3.45 respectively, in a ratio of 1:2 (w/w). Higher values of encapsulation efficiency and antioxidant activity were observed for pea protein/carrageenan and pea protein/tragacanth. DSC and FTIR analyses confirmed the encapsulation. The application of pea protein/tragacanth particles in the production of candies proved to be efficient for providing the highest percentages of phenolic compound release in the intestinal phase.

Fortification of Pectin/Blackberry Hydrogels with Apple Fibers: Effect on Phenolics, Antioxidant Activity and Inhibition of α-Glucosidase.

The objective of this study was to prepare hydrogels based on pectin and blackberry juice and additionally to fortify those hydrogels with apple fiber. For that purpose, two types of pectin (low methoxylated and high methoxylated) were used, and fortification was conducted with the addition of 10% of apple fiber. The hydrogels were evaluated for phenolic compounds, antioxidant activity and inhibition of α-glucosidase. In addition, the stability of these parameters after 8 months of storage was evaluated. Pectin type and addition of apple fiber had an impact on investigated parameters. Low methoxylated pectin hydrogels had a higher concentration of anthocyanins than high methoxylated pectin hydrogels, while the addition of apple fibers caused a decrease in anthocyanin content. However, fortified hydrogels had higher antioxidant activity due to the presence of phenolics from apple fibers. The results showed that anthocyanins were more favorable in inhibiting α-glucosidase because samples with higher anthocyanins concentration had lower IC50 values. Obtained hydrogels can be used as intermediate products or ingredients (like fruit fillings or spreads) for the improvement or development of novel food products to increase their fiber content and antioxidant potential.

Encapsulation of Blackberry Phenolics and Volatiles Using Apple Fibers and Disaccharides.

The objective of this study was to determine the effect of disaccharides on the encapsulation of the phenolics and volatiles of blackberry juice with the use of apple fiber. For this purpose, apple fiber/blackberry microparticles were prepared as the control, as well as microparticles additionally containing disaccharides, i.e., sucrose or trehalose. Fiber:disaccharide ratios were 1:0.5, 1:1, and 1:2. Formulated microparticles were characterized for total phenolics, proanthocyanidins, individual phenolics, antioxidant activity, flavor profiles, and color parameters. Both applied disaccharides affected the encapsulation of phenolics and volatiles by the apple fibers. Control microparticles had a higher content of phenolics than microparticles with disaccharides. Comparing disaccharides, the microparticles with trehalose had a higher content of phenolics than the ones containing sucrose. The amount of proanthocyanidins in the control microparticles was 47.81 mg PB2/100 g; in trehalose, the microparticles ranged from 39.88 to 42.99 mg PB2/100 g, and in sucrose, the microparticles ranged from 12.98 to 26.42 mg PB2/100 g, depending on the fiber:disaccharide ratio. Cyanidin-3-glucoside was the dominant anthocyanin. Its amount in the control microparticles was 151.97 mg/100 g, while in the trehalose microparticles, this ranged from 111.97 to 142.56 mg /100 g and in sucrose microparticles, from 100.28 to 138.74 mg /100 g. On the other hand, microparticles with disaccharides had a higher content of volatiles than the control microparticles. Trehalose microparticles had a higher content of volatiles than sucrose ones. These results show that the formulation of microparticles, i.e., the selection of carriers, had an important role in the final quality of the encapsulates.

Apple Fibers as Carriers of Blackberry Juice Polyphenols: Development of Natural Functional Food Additives.

Blackberry polyphenols possess various health-promoting properties. Since they are very sensitive to environmental conditions such as the presence of light, oxygen and high temperatures, the application of such compounds is restricted. Fibers are recognized as efficient carriers of polyphenols and are often used in polyphenols encapsulation. In the present study, the ability of apple fiber to adsorb blackberry juice polyphenols was examined. Freeze-dried apple fiber/blackberry juice complexes were prepared with different amounts of fibers (1%, 2%, 4%, 6%, 8% and 10%) and a constant amount of blackberry juice. Polyphenol profile, antioxidant activity, inhibition of the α-amylase, color parameters, as well as the IR spectra, of the obtained complexes were assessed. The results showed a negative effect of higher amounts of fiber (more than 2%) on the adsorption of polyphenols and the antioxidant activity of complexes. With the proper formulation, apple fibers can serve as polyphenol carriers, and thus the application as novel food additives can be considered.

Anti-Proliferative and Anti-Telomerase Effects of Blackberry Juice and Berry- Derived Polyphenols on HepG2 Liver Cancer Cells and Normal Human Blood Mononuclear Cells.

Previous studies have provided strong evidence for the anticancer activity of berry fruits. In this study, we investigated the effects of blackberry juice and three berry- polyphenolic compounds on cell proliferation and telomerase activity in human hepatoma HepG2 and normal peripheral blood mononuclear cells (PBMCs). The cell viability and telomerase activity were measured by MTT and TRAP assay, respectively. Berry effects on the expression of genes were determined by quantitative RT-PCR assay. Blackberry, gallic acid, and resveratrol inhibited proliferation of both HepG2 and PBMC cells in a dosedependent manner. Resveratrol was more effective than gallic acid for reducing the viability of HepG2 cells, but both showed the same level of growth inhibition in PBMC cells. Berry, resveratrol, and gallic acid significantly inhibited telomerase activity in HepG2 cells. The antiproliferative effect of berry was associated with apoptotic DNA fragmentation. Gallic acid was more effective for reducing telomerase activity than resveratrol, but anthocyanin moderately increased telomerase activity in cancer cells. Telomerase activity was induced by all three polyphenols in PBMCs. Overall, Krumanin chloride was more effective to induce telomerase than gallic acid and resveratrol in PBMC cells. There was no significant difference in hTERT, hTR, and Dnmts expressions between berry treated and the control untreated HepG2 cells. But, a significant downregulation of HDAC1 and HDAC2 and upregulation of SIRT1 were observed in berry-treated cells. These data indicate that the berry anticancer effect is associated with antitelomerase activity and changes in HDACs expression. The data also suggest that berry antitelomerase activity is mainly related to its gallic acid and resveratrol, but not anthocyanin content.

Науково-методичні та практичні інновації Інституту садівництва НААН України у виготовленні продуктів здорового харчування з плодів калини, ожини, кизилу, терну

The paper presents the results of evaluating the primary components (pasteurized natural monojuices) for the production of blended juices and syrups from the fruits of pre-selected species and cultivars of minor fruit and small fruit crops according to the biochemical (dry substances, sugar, acidity), physicochemical (sediment) and organoleptic (color, aroma, transparency) indicators. The authors have described some elements of the methods of processing the berries of the above mentioned crops. The test technological works have enabled to establish the modes of the pasteurization of blended juices by means of the continuous pasteurization. In particular, when producing blended apple-wild plum tree and apple-viburnum juices and syrups the packing temperature is to be 85 °С. The temperature in the pasteurizer zones should be: for the first zone 85 °С, the second 28 and the third 20 °С. The time of exposure in the mentioned zones must be - 26, 6 and 3 minutes respectively. The elaboration the methodological recommendations on the technology for making healthy food products (juices and syrups from the fruits of minor crops) as well as the preparation of technological instructions for the manufacturing of blended blackberry juice, has been substantiated; blended apple-wild plum tree and viburnum-apple juices, dogwood-blackberry and dogwood-field syrups. The technologies for making blended juices from blackberries, dogwood-blackberry syrup, blended apple-wild plum tree juice, dogwood-wild plum tree syrup, blended viburnum-apple juice have passed successfully the production testing at the IH NAAS. The characteristics of ready-made healthy food products are presented: blended unclarified wild plum tree-apple juice "Kozatska mits", blackberry-apple juice "Medova ozhynka", viburnum-apple juice "Kalynonka" and blackberry-dogwood syrup "Medovyi rubin" and dogwood-honey "Medova badioris

Wintergreen Oil: A Boon or Curse

”All things are poison and nothing is without poison, only the dose permits something not be poisonous” – Paracelsus. Some substances are so toxic that small amounts can be harmful. Here is a case detail about a 58-year-old male who consumed a small quantity of methyl salicylate, mistaking it to Indian blackberry juice. He ended up undergoing six cycles of hemodialysis and critical care polyneuropathy.

Immunomodulatory Properties of Blackberry Anthocyanins in THP-1 Derived Macrophages.

An anthocyanin-rich diet is considered to protect against chronic inflammatory processes although the bioavailability of anthocyanins is regarded as rather low. Moreover, the immunomodulatory role of anthocyanins is not fully understood yet. In the present study, fractions of blackberry (Rubus fruticosus) juice were investigated in plasma-relevant concentrations with respect to their immunomodulatory properties in lipopolysaccharide (LPS)-challenged THP-1-derived macrophages. The complex blackberry extract acted ineffective as well as potential degradation products. Cyanidin-3O-glucoside (Cy3glc), the main constituent of blackberry anthocyanins, diminished TNF-α levels at a concentration of 0.02 µg/mL, indicating protective effects as measured with quantitative RT-PCR and multiplex cytokine assays. LPS-boosted activity of transcription factor nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) of differentiated THP-1 reporter gene cells was marginally inhibited by Cy3glc. LPS-induced microRNA-155 was further increased, supporting the evidence of protection. Of note, fractions obtained from blackberry juice, in particular cyanidin-3O-(6″-dioxalylglucoside), were displaying potential pro-inflammatory properties as these elevated IL-6 and TNF-α levels. In conclusion, highly purified anthocyanin fractions of blackberry juice display both anti- and pro-inflammatory properties at plasma-relevant concentrations depending on their structure and substitution pattern.

Consumer profile: blackberry processing with different types of sugars

Due to its high medicinal and nutritional values, blackberries have become increasingly interesting to producers and consumers. People are looking for healthier options to consume sugar with greater nutritional enrichment. However, replacement of the type of sugar is associated with significant changes in some parameters, finding suitable replacements that result in satisfactory products can be challenging. The aim of this study was to evaluate the influence of different sugars (white refined sugar, white crystal sugar, demerara sugar, brown sugar and coconut sugar) on the physicochemical, physical and sensory aspects of blackberry juices and jellies. The type of sugar influenced the physicochemical and physical characteristics of blackberry jelly and juice, which reflected the differences in acceptability of the final product. Information on the type of sugar and its benefits influenced the sensory acceptance of blackberry jelly and juice.

Polyphenols and Antioxidant Activity of Citrus Fiber/Blackberry Juice Complexes.

The objective of this study was to investigate the use of citrus fiber as a carrier of blackberry juice polyphenols. For that purpose, freeze-dried complexes with blackberry juice and different amounts of citrus fiber (1%, 2% and 4%) were prepared. Complexes were evaluated spectrophotometrically for total polyphenols, proanthocyanidins and antioxidant activity. Analyses of individual polyphenols were performed using high-performance liquid chromatography. IR spectra were recorded to confirm encapsulation. All analyses were performed after preparation and after eight months of storage, in order to examine the stability of formed complexes. The obtained results indicated that increasing the amount of fiber led to a decrease in the concentration of polyphenols and the antioxidant activity of complexes. Cyanidin 3-glucoside was the prevalent anthocyanin in complexes (138.32–246.45 mg/100 g), while cyanidin 3-dioxalylglucoside was present at lower concentrations (22.19–31.45 mg/100 g). The other identified and quantified polyphenols were hesperidin (from citrus fiber), ellagic acid and quercetin (1317.59–1571.65 mg/100 g, 31.94–50.11 mg/100 g and 20.11–33.77 mg/100 g, respectively). Degradation of polyphenols occurred during storage. Results obtained in this study confirmed that citrus fiber could be used for the formulation of novel bioactive additives. Such additives could enhance the antioxidant potential of products to which they are added, such as baked goods, dairy, or fruit products.