The influence of natural sweetener (Stevia rebaudiana Bertoni) on bioactive compounds content in chokeberry juice

The aim was to determine the differences in nutritional quality between chokeberry juices sweetened with sucrose and green stevia powder. The quality of chokeberry juices during refrigerated storage was studied. Chokeberry juices with added green stevia powder had the higher content of analyzed bioactive compounds in comparison with juice samples sweetened with sucrose; vitamin C content increased up to two times, total phenol content up to 6% and antioxidant capacity for 3%. The content of studied bioactive compounds and antioxidant capacity during storage in period of 30 and 60 days was significantly reduced with the exception of steviol glycosides which content was not significantly reduced during the storage period.

Practical applications

Chokeberry juice is a popular, widespread product of chokeberry fruit characteristic for the dark intense red color, slightly unpleasant, bitter taste and extremely rich bioactive compounds content. Because of high nutritional quality, chokeberry juice is often consumed but with the biggest barrier of characteristic astringent taste which can be diminished by addition of sweetener. Producers often combine a low‐cost sweeteners like sucrose which shows numerous negative effects on human health. A good alternative to the sucrose and artificial sweeteners are natural sweeteners extracted from the plant material like steviol glycosides. Except sweetness, stevia products like green powder shows beneficial effect on the bioactive compounds content in the juices sweetened with it. Juices sweetened with stevia shows increased content of bioactive compounds, so such product may represent quality product from category of functional food.     

Comparative Analysis of the Antioxidant Capacity of Selected Fruit Juices and Nectars: Chokeberry Juice as a Rich Source of Polyphenols

The bioactive compounds, and hence the antioxidant capacity, of fruit juice are affected by a given type of juice and fruit processing conditions. In this study, some polyphenol-rich juices and nectars were compared, considering the manufacturing conditions (Stage I). Organic chokeberry juice was determined to possess the highest antioxidant capacity, which was 4- to 10-fold higher than in other popular juices. Subsequently, this juice was analyzed for selected flavonoids (flavanols, flavonols, flavones) and phenolic acids (Stage II). The results showed that chokeberry juice was a rich source of chlorogenic and neochlorogenic acids. The high total content of polyphenols and high antioxidant capacity encourage further clinical research on chokeberry juice, in the context of cardiovascular diseases prophylaxis.     

Antioxidant synergism between fruit juice and <Emphasis Type="Italic">α</Emphasis>-tocopherol. A comparison between high phenolic black chokeberry (<Emphasis Type="Italic">Aronia melanocarpa</Emphasis>) and high ascorbic blackcurrant (<Emphasis Type="Italic">Ribes nigrum</Emphasis>)

Black chokeberry juice (Aronia melanocarpa, Elliot), blackcurrant juice (Ribes nigrum, Ben Lomond) and α-tocopherol were found to protect phosphatidyl choline against oxidation in a peroxidating liposome system as evidenced by lag phases for formation of conjugated dienes. When present together, black chokeberry juice and α-tocopherol showed a clear synergistic effect on the length of the lag phase, while effects of blackcurrant juice and α-tocopherol were additive. The concentration of total phenolics in black chokeberry juice was six times higher than in blackcurrant juice (gallic acid equivalents). Ascorbic acid corresponded to 1% of total phenolics in black chokeberry juice and 10% in blackcurrant juice. Based on the length of the lag phase, the phenolics present in black chokeberry were on an average, twice efficient as scavengers of lipid peroxyl radicals as phenolics in blackcurrant. Black chokeberry was by HPLC analysis of peroxidating liposomes, in contrast to blackcurrant, found to protect α-tocopherol efficiently against oxidation to the end of the lag phase. The phenolics present in black chokeberry juice were concluded to be more efficient in regenerating or protecting α-tocopherol than ascorbic acid or the phenolics in blackcurrant. As for the phenolics, this was further evidenced by ranking of their radical scavenging activity as studied by ESR-spectroscopy.     

Effects of different enzymatic pre-press maceration treatments on the release of phenols into blackcurrant juice

The effects of different pectinolytic enzyme treatments on the release of phenolic compounds from blackcurrant berry mash into juice in experimental blackcurrant juice production were examined. The influence of enzyme dose (0–0.1% by weight), degree of berry crushing, maceration time, and temperature on the total phenol concentration, the juice yield, and on polysaccharide degradation were evaluated for four commercial, fungal enzyme preparations in statistically designed experimental templates. In optimal experimental conditions, treatments with Macer8 [FJ] and Pectinex Ultra SP-L released ~6500 and 6650 mg gallic acid equivalents/L of total phenols, respectively. These levels correspond to increases of 14–15% compared to the juice extracted without enzymes, and were significantly higher than those achieved with Rapidase BE Super and Grindamyl pectinase treatments. Increased enzyme dosage gave larger juice yields and higher phenol concentrations. There was a positive, linear correlation between degradation of the substrate polysaccharides and the amount of phenols released. The juice samples inhibited the oxidation of human low-density lipoproteins in vitro in a dose-dependent matter. The non-enzyme-treated sample exhibited higher antioxidant activity than the enzyme-treated juices at equimolar test levels of phenols, presumably because of differences in their phenolic profiles.     

Quantitative bioactive compounds assessment and their relative contribution to the antioxidant capacity of commercial orange juices

Dietary recommendations for healthy eating include the consumption of fruit juices whose health effects are ascribed, in part, to carotenoids, phenolic compounds and vitamin C. These bioactive compounds have been implicated in the reduction of degenerative human diseases, mainly due to their antioxidant potential. Orange juice is characterized by substantial accumulation (apart from ascorbic acid) of flavonoids and carotenoids. Commercial orange juice is the main human dietary source of antioxidant compounds in developed countries. The qualitative and quantitative determination of carotenoid, flavonoid and vitamin C content of Spanish commercial orange juices was achieved by high‐performance liquid chromatography. The health‐related properties of bioactive compounds contained in orange juice are based on their antioxidant activity. The antioxidant capacity of these juices was assessed by 2,2‐diphenyl‐1‐picrylhydrazyl stable radical scavenging and was compared with a freshly squeezed orange juice. In addition, the relative contribution of the different bioactive compounds to the antioxidant activity of orange juices was calculated. Total vitamin C was found to be the major contributor to the antioxidant potential of the orange juices studied, followed by flavonoid and carotenoid compounds. Ascorbic acid, total vitamin C and β‐cryptoxanthin content correlated positively with the free‐radical scavenging parameters. No significant differences, in terms of antioxidant capacity, were found between commercial traditional pasteurized orange juices and freshly squeezed orange juice. Copyright © 2003 Society of Chemical Industry     

Comparison of the polyphenolic composition and antioxidant activity of European commercial fruit juices

Thirty six commercial European fruit juices were tested to ascertain their antioxidant capacity and polyphenolic composition. Six of the products were labelled 100% pomegranate juice, the others included 20 brands of diluted pomegranate juice or pomegranate blended with other fruit juices and 10 different non-pomegranate fruit juices. The antioxidant capacity of all the juices was determined while anthocyanin, ellagitannin and ellagic acid profiles of the 26 pomegranate juices and pomegranate juice blends were obtained using HPLC-PDA-MS(2). Additional analysis was conducted on seven of the juices using HPLC with an on-line antioxidant detection system. Three of the "pure" pomegranate juices had the highest ellagitannin content and the highest antioxidant capacity. Only one of these three juices was rich in anthocyanins. The other "pure juices" had differences in their HPLC "pomegranate" fingerprint and also had a lower antioxidant capacity, in some cases lower than that of some of the blended juices. Vitamin C rather than phenolic compounds was the major contributor to the antioxidant capacity for some of the juices. Statistical analysis of both the antioxidant assay and the HPLC on-line antioxidant data demonstrated that the ellagitannins were the major antioxidants in the pomegranate juices. The complexity of the polyphenolic profile of pomegranates necessitates the use of HPLC-PDA-MS(2) for a thorough evaluation of juice composition and authenticity.     

朝鲜蓟花苞汁总酚、总黄酮、抗氧化性比较及体外模拟胃肠消化特性

比较不同部位花苞汁及体外模拟胃肠消化前后总酚、总黄酮质量浓度,并通过总还原力和1,1-二苯基-2-三硝基苯肼自由基、2,2’-联氮-双-3-乙基苯并噻唑啉-6-磺酸阳离子自由基、超氧阴离子自由基清除率4 种方法评价其抗氧化能力。结果表明：花托汁总酚质量浓度为2.46 mg/mL,分别为内苞叶汁、外苞叶汁的1.13、1.94 倍;总黄酮质量浓度为6.53 mg/mL,分别为内苞叶汁、外苞叶汁的1.15、2.06 倍。在4 种抗氧化评价体系中,自由基清除能力强弱顺序均为花托汁＞内苞叶汁＞外苞叶汁,且自由基清除率均随着样品总酚质量浓度增加而增大。在体外模拟胃肠消化实验中,以花托汁为样品,经过模拟胃液处理后,模拟胃液组和胃酸对照组抗氧化性均显著增强（P＜0.05）,但经过模拟肠液处理后抗氧化能力下降,表明胃蛋白酶、胃酸、胰蛋白酶均能促使抗氧化活性因子释放,提高抗氧化能力。     

Polyphenols,ascorbic acid and antioxidant capacity of commercial nutritional drinks,fruit juices,smoothies and teas

Polyphenols of plant origin have received special interest in the last decade because of their potential health benefits. Consequently, many beverages with words ‘antioxidant’ and ‘polyphenols’ have been developed. However, many of the claims are misleading because some beverages so labelled have either no or minimal levels of polyphenols. The objectives of this study were to quantify polyphenols (TPC) and ascorbic acid contents and antioxidant capacity (AOC) of different beverages; identify major polyphenols in beverages that showed higher TPC; correlate the claim on the label with TPC and AOC; and determine the impact of consumer refrigerated storage on TPC and AOC of aronia, blackcurrant and pomegranate juices which contained the most TPC and AOC. Major polyphenols identified from these juices included anthocyanins, myricetin and epicatechin. TPC of aronia, blackcurrant and pomegranate juices was relatively stable during consumer refrigerated storage, even when the juice had been intermittently exposed to air.     

Determination of phenolic composition and antioxidant capacity of blood orange juices obtained from cvs. Moro and Sanguinello (Citrus sinensis (L.) Osbeck) grown in Turkey

The phenolic compounds and antioxidant capacities of orange juices obtained from cvs. Moro and Sanguinello (Citrus sinensis (L.) Osbeck) were determined. A high-performance liquid chromatographic method coupled with diode-array detection was used to identify and quantify phenolic compounds of the orange juices. A total of 18 phenolic compounds were identified and quantified in Moro and Sanguinello orange juices, including hydroxybenzoic acids (2), hydroxycinnamic acids (5), flavanones (5), and anthocyanins (6). It was observed that total phenolic content of Moro juice was higher than that of Sanguinello juice. Ferulic acid was the most dominant hydroxycinnamic acid and cyanidin 3-(6″-malonyl glucoside) and cyanidin 3-glucoside were the most dominant anthocyanins in both cultivars. Antioxidant activities of orange juices were measured using the DPPH^· (2,2-diphenyl-1-picrylhydrazyl) method. According to DPPH^· assays, the antioxidant capacity of Moro juice was found to be higher than that of Sanguinello juice.     

Antioxidant activity of pasteurized and sterilized commercial red orange juices

Blood orange juice is a typical Italian product whose red color is primarily associated with anthocyanin pigments. Two orange-based products are present on the market: pasteurized pure juice with 40 days of shelf life, and sterilized beverage containing minimum 12% of concentrated fruit juice. The aim of the present paper is to verify the relationships between the antioxidant properties and the anthocyanins content in a sampling of pasteurized and sterilized commercial red orange juices. The anthocyanins composition was determined by HPLC-MS/MS, while the antioxidant activity was evaluated by the Briggs-Rauscher reaction, selected in order to acquire information at acid pH values, by three radical scavenging assays (DMPD, 2-2'-azinobis-(3-ethylenbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), DPPH), and by FRAP assay to monitor the ferric reducing power. Results showed that antioxidant activity, particularly when measured by ABTS method, is positively related to the content of anthocyanins and that the reduction of anthocyanins content, typical of commercial long-shelf life juices, leads to a remarkable loss of antioxidant power.     

Evaluation of the antioxidant activity of asparagus,broccoli and their juices

Antioxidant activity of asparagus, broccoli and their juices was evaluated using 2,2′-diphenyl-l-picrylhydrazyl (DPPH), 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and β-carotene bleaching assays. Asparagus showed greater antioxidant activity than broccoli. Asparagus juice also had greater antioxidant activity than broccoli juice. Methanol and acetone extracts of asparagus and broccoli had significantly greater antioxidant activity than their water extracts. Asparagus and broccoli extracts, as well as their juices, showed no significant difference in total phenolics content. However, asparagus contained more flavonoids than broccoli. The antioxidant activity of asparagus and broccoli extracts demonstrated a linear relationship with their flavonoid content.     

Changes of health-related compounds throughout cold storage of tomato juice stabilized by thermal or high intensity pulsed electric field treatments

The effect of high intensity pulsed electric fields (HIPEF) processing (35 kV/cm for 1500 μs in bipolar 4-μs pulses at 100 Hz, with an energy density of 8269 kJ/L) on the main bioactive compounds and antioxidant capacity of tomato juice was investigated and compared to heat pasteurization (90 °C for 1 min or 30 s) having the fresh juice as a reference. HIPEF and heat treated tomato juices showed higher lycopene and lower vitamin C levels than the untreated juice. However, no significant changes in the total phenolic content and antioxidant capacity were observed between treated and fresh juices just after processing. Lycopene, vitamin C and antioxidant capacity of both treated and untreated juices decreased exponentially during storage following a first order kinetics (R² = 0.763–0.987), whereas tomato juices maintained their initial phenolic content. HIPEF-treated tomato juice maintained higher lycopene and vitamin C content than the thermally treated juices during the storage time. Hence, the application of HIPEF may be appropriate to achieve nutritious and fresh like tomato juice.

Industrial relevance

HIPEF processing can lead to tomato juice with higher nutritional value than that thermally processed. HIPEF-treated (35 kV/cm for 1500 μs with 4-μs bipolar pulses at 100 Hz, energy input of 8269 kJ/L) tomato juice shows greater lycopene, vitamin C and antioxidant capacity just after the treatment and during the storage time than heat treated (90 °C­30 s and 90 °C­60 s) tomato juice. Therefore, HIPEF technology is a feasible alternative to thermal treatment to obtain tomato juice with a high presence of health-related compounds.     

Effects of drying methods on contents of bioactive compounds and antioxidant activities of black chokeberries (<Emphasis Type="Italic">Aronia melanocarpa</Emphasis>)

Optimal drying techniques for maintaining high levels of bioactive compounds and antioxidant activities in black chokeberries were investigated. Effects of 3 drying methods on total bioactive compound contents and in vitro antioxidant activities in 80% ethanol extracts were evaluated. Fresh black chokeberries were dried using sun-drying, freeze-drying, and oven-drying. Highest amounts of total polyphenols, flavonoids, and anthocyanins were detected in freeze-dried black chokeberry extracts after sun and oven-drying. 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), and superoxide anion scavenging activities in black chokeberry extracts were also evaluated. Freeze-dried berries produced strongest antioxidant activities. Freeze-drying was the optimal drying method for maintaining high levels of bioactive compounds in 80% ethanol extracts of dried black chokeberries.     

Antioxidant activity and total phenolic,organic acid and sugar content in commercial pomegranate juices

Pomegranate fruit and pomegranate juices (PJs) have taken great attention for their health benefits in the last years. The purpose of this study is to analyse the antioxidant activities, along with the organic acid and sugar contents of pomegranate juices sold in the Turkish markets. In the present study, we evaluated total phenolics (TPs), free radical scavenging capacity by 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing capacity of seven commercial PJs. Organic acid and sugar contents of juices were determined by capillary zone electrophoresis. The results showed that commercial pomegranate juices had markedly high total phenolic contents and antioxidant capacity. Fructose (F) and glucose (G) were found as the major sugars. The major acids were citric and malic. From the F/G ratio, organic acid profiles, TPs, and antioxidant capacity values, a possible adulteration was detected in one of the juices.     

Comparative study of phenolic content and antioxidant activity of strawberry puree,clear, and cloudy juices

The aim of this study was to determine the concentrations of phenolic compounds and their antioxidant activity in different kinds of juice: clear, cloudy, and puree which were made from three different strawberry cultivars (Elkat, Kent, and Senga Sengana). The anthocyanins, p-coumaric acid, ellagic acid, quercetin, keampferol derivatives, (+)-catechin, proanthocyanidins content and degree of proanthocyanidin polymerization, were determined both in the fresh and after 6 months of storage at 4 and 30 °C. Freshly produced juices contained higher amounts of phenolics, especially of anthocyanins and proanthocyanidins, than those stored for 6 months at 4 and 30 °C. The processing of the clear juice showed the higher loss of all phenolic compounds. The antioxidant capacity was the smallest for clear, and the highest for the puree juices. This was assessed by measurements made with different antioxidant activity assays: ABTS and FRAP. The puree of strawberry juice had significantly higher levels of the phenolic compounds and showed more antioxidant activity than the clear and cloudy juices, before and after storage in all strawberry cultivars.     

Phytochemical profile of a blend of black chokeberry and lemon juice with cholinesterase inhibitory effect and antioxidant potential

In this study, black chokeberry concentrate was added (5% w/v) to lemon juice, since previous reports suggested potential health benefits of this blend. The phytochemical composition, antioxidant capacity (scavenging of DPPH, superoxide and hydroxyl radicals, and hypochlorous acid), and inhibitory activity against cholinesterase of the new blend were determined and compared with those of lemon juice and chokeberry in citric acid (5%). The chokeberry concentrate, rich in cyanidin-glycosides, quercetin derivatives, and 3-O-caffeoylquinic acid, and lemon juice, possessing flavones, flavanones, quercetin derivates, and hydroxycinnamic acids, were characterised. The new drink showed a higher antioxidant effect than the chokeberry or lemon controls for all the tested methods, except for hypochlorous acid, in which lemon juice displayed higher activity. Both the lemon juice and chokeberry controls inhibited acetylcholinesterase and butyrylcholinesterase, and this effect was increased in the new mixtures. The results of the different radical scavenging assays indicate that the lemon–black chokeberry (5% w/v) mixture was more antioxidative than the respective controls separately. Moreover, their inhibition of cholinesterase is of interest regarding neurodegenerative disorders such as Alzheimer’s disease, Parkinson’s disease, or senile dementia.     

Antioxidative capacity of tomato products

The antioxidative capacity of methanol/water and hexane extracts of five tomato juices, four canned tomatoes and four tomato pastes was measured using two test systems: with 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS⁺) and with linoleic acid emulsion. In both the ABTS assay and the linoleic acid system, most of the antioxidative capacity of analysed products was from the methanol-water fraction, which contained polyphenols and ascorbic acid. On the basis of the wet weight of the tomato products, tomato pastes had the highest activity towards ABTS⁺ (micromoles of Trolox equivalents per gram) followed by tomato juices, and canned tomatoes. The inhibition of formation of thiobarbituric acid-reactive substances in the linoleic acid emulsion was strongly dependent on antioxidant concentration. The results suggest that tomato products, in addition to fresh tomatoes, may also be important in supplying dietary antioxidant, especially polyphenols and carotenoids.     

Deacidification of red and white wines by a mutant ofSchizosaccharomyces malidevoransunder commercial winemaking conditions

A mutant ofSchizosaccharomyces malidevorans, which utilizes malic acid more rapidly than the wild-type strain and does not utilize significant amounts of glucose or fructose, was used in commercial scale deacidification of grape juice during two vintages in a New Zealand winery. Four trials were conducted in Chardonnay, Semillon and Cabernet Sauvignon juices, 1000–4500 l. In the first two trials, the juices were inoculated with the alcoholic fermentation yeast,Saccharomyces cerevisiae, 33–48 h after the mutant inoculation. In the remaining two trials, the juices were inoculated simultaneously with the mutant andS. cerevisiae. Malic acid, ranging from 3.5–10 g l⁻¹in the juices, was completely degraded within 21–73 h. TheSchiz. malidevoransmutant utilized malic acid at sulfur dioxide levels and temperatures used in red and white winemaking. The wines produced in the trials lacked obvious organoleptic defects. They were blended with untreated wines for acid balance and retailed as varietal wines.     

黑果腺肋花楸果汁饮料研制及其品质与抗氧化性评价

为研制黑果腺肋花楸果汁饮料并探究其抗氧化活性,以黑果腺肋花楸果实为主要原料,添加蔗糖、柠檬酸和β-环糊精等辅料,以感官评分为指标,通过单因素实验和正交试验确定黑果腺肋花楸果汁饮料的最佳配方为:黑果腺肋花楸浸提汁用量60%,60%蔗糖糖浆添加量10%,2%柠檬酸溶液添加量2.0%,1% β-环糊精添加量3.0%,该配方所制得的饮料感官评分可达94.5分,其富含16种氨基酸,总量达到374.79 μg/mL,具有黑果腺肋花楸果实的特征香气,色泽均一明亮,风味协调爽口,质地均匀;体外抗氧化活性研究表明:该饮料对DPPH自由基清除率、羟自由基清除率、ABTS+自由基清除能力以及总还原能力分别为36.42%、32.58%、0.54 mmol/L和0.289,说明其具有较好的抗氧化能力。本实验结果为黑果腺肋花楸功能性饮料的开发提供了理论依据。     

The effect of iron, tin, aluminium, and chromium on fading, discoloration, and precipitation in berry and red beet juices.

The effect of iron(II), tin(II), aluminium(III), and chromium(III) on the properties of red whortleberry, blackcurrant, and red beet juices was followed during storage for 10 months at 5 degrees C. The colour and pH changes were studied, and the precipitates formed were weighed and their metal contents assayed. Of the metals tested, only tin caused bluish discoloration in the berry juices. In the case of iron, aluminium, and chromium the low pH prevented this type of discoloration. In berry juices, some increases in colour intensity took place with the lowering of pH value, whereas in red beet juice the opposite change occurred. The colour changes due to storage appear to take place irrespective of the metals. Precipitation is enhanced in red whortleberry juice only by tin, and in blackcurrant juice by tin and iron. In red beet juice, precipitation is increased by the lowering of pH resulting from metal salt addition. In general, increase in the amount of metal added increased the metal content of the precipitate. Iron showed the greatest tendency to become bound in the precipitate, particularly in blackcurrant and red beet juice. The suitabilities of the metals for canning purposes are considered. Chromium, in particular, has interesting possibilities in view of the low degree of colour change associated with it.