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Industrial Crops and Products 34 (2011) 1301– 1309

Contents lists available at ScienceDirect

Industrial Crops and Products

journa l h o me page: www.elsev ier .com/ locate / indcrop

lack currant polyphenols: Their storage stability and microencapsulation

nna M. Bakowska-Barczaka,b,∗, Paul P. Kolodziejczykb

Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton AB T6G 2P5, CanadaDepartment of Fruits, Vegetables and Cereals Technology, Wroclaw Environmental and Life Science University, ul. Norwida 25, 50-375 Wroclaw, Poland

r t i c l e i n f o

rticle history:eceived 20 April 2010eceived in revised form3 September 2010ccepted 4 October 2010vailable online 29 October 2010

eywords:lack currantolyphenolsntioxidant activityicroencapsulationaltodextrin

nulin

a b s t r a c t

Interest in the consumption of fresh fruits is, to a large extent, due to its content of bioactive nutrientsand their importance as dietary antioxidants. There is a growing demand for delivery of antioxidantsthrough functional foods with the related challenge of protecting their bioactivity during food process-ing and subsequent passage through the gastrointestinal tract. This study focuses on the evaluation ofconcentration of bioactive compounds in black currant berries (Ribes nigrum L.) and retention of blackcurrant polyphenol compounds and their antioxidant activity after microencapsulation by spray-drying.The polyphenol contents and antioxidant activities were assessed for 5 black currant cultivars grown inCanada in fresh and stored fruits at −20 ◦C for 9 months. The Ben Alder cultivar was the richest in antho-cyanins and flavonols content with high antioxidant potential measured with ABTS and DPPH radicals (4.5and 2.4 mM/100 g). Black currant polyphenols were stable during 9 month of storage at −20 ◦C. The resultsof this study indicated that in black currants storage did not affect negatively the antioxidant capacity.The good stability of bioactive compounds of black currants during freezer storage allows prolonging thestorage time of these berries. Maltodextrins with different DE (dextrose equivalent): DE11, DE18, DE21

and inulin were selected as wall material. The stability of encapsulated polyphenols during 12 monthsstorage at 8 ◦C and 25 ◦C was evaluated. Compared to maltodextrins DE18 and DE21, maltodextrin DE11had not only higher drying yield but also offered better protection for phenolics during storage. Radicalscavenging activity studies demonstrated significant antioxidant activity of microencapsulated powdersbefore and after storage. The black currant polyphenol microcapsules described in this study represent apromising food additive for incorporation into functional foods due to antioxidant content.

. Introduction

There has been increasing interest for the inclusion of fresh fruitsn the human diet, mainly for the health benefits associated withheir consumption (Liu et al., 2000; Martin et al., 2002). A majorenefit from a higher intake of berries and fruits, including blackurrant (Ribes nigrum L.) may be due to increased consumption ofitamins, minerals, dietary fibre, and other bioactive constituents.

Black currant berries are excellent sources of bioactive compo-ents such as anthocyanins, flavonols, procyanidins, and phenoliccids. Previous study has shown that black currants are a goodource of bioactive polyphenols (500–1342 mg/100 g of total

olyphenols), mostly anthocyanins (160–411 mg/100 g) (Moyer etl., 2002). Anthocyanins have not been recognized as a physiolog-cal functional food factor. However, in recent years, numerous

∗ Corresponding author at: Department of Fruits, Vegetables and Cereals Technol-gy, Wroclaw Environmental and Life Science University, ul. Norwida 25, 50-375roclaw, Poland. Tel.: +48 71 3205 474; fax: +48 71 3205 477.

E-mail address: anna.bakowska-barczak@up.wroc.plA.M. Bakowska-Barczak).

926-6690/$ – see front matter © 2010 Elsevier B.V. All rights reserved.oi:10.1016/j.indcrop.2010.10.002

© 2010 Elsevier B.V. All rights reserved.

studies have shown that anthocyanins display a wide rangeof biological activities including antioxidant, antimicrobial andanti-carcinogenic activities; improvement of vision; induction ofapoptosis; and neuroprotective effects (Han et al., 2007; Ramos,2008; Soobrattee et al., 2006; Neto, 2007).

Recently, attention has been focused on anti-inflammatoryactivities of anthocyanins (Seeram et al., 2001).

Although, anthocyanins have been shown to act as antioxidants,they may exert a wide range of health benefits through differentmechanisms. Anthocyanins may interrupt, or reverse, the car-cinogenesis process by acting on intracellular signaling moleculesinvolved in the initiation and/or promotion progress of cancer.The effects of the anthocyanins seem to be cell type- and dose-dependent. Depending on their specific structures, anthocyaninsaffect different cellular signaling elements that are crucial for theregulation of cell proliferation (Jing et al., 2008).

An example of such mechanism was presented by Tsuda etal. (2006). Authors have demonstrated the significant change

of adipocytokine expression in the human adipocytes treatedwith anthocyanins. Based on the gene expression profile, authorsdemonstrated up-regulation of adiponectin and down-regulationof plasmminogen activator inhibitor-1 and interleukin-6. The study

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emonstrated that anthocyanins can regulate adipocytokine genexpression to ameliorate adipocyte function related with obesitynd diabetes.

Some anthocyanins are capable of reducing the blood glu-ose level and reverse the decrease of pancreatic beta cells morefficiently than glimepiride, a known insulin secretion agentBakowska-Barczak et al., 2009). Therefore, the dietary intake ofolyphenol-rich food might be beneficial in preventing the onsetf type 2 diabetes mellitus.

The cyclooxygenase isoform COX-2 is inducible and contributeso pathological processes such as inflammation and abnormal cellroliferation, is over-expressed in human colon carcinomas. Pre-iously, black currant anthocyanin extract was shown to be aotential COX-1 and COX-2 inhibitor (Bakowska-Barczak et al.,009).

The stability of polyphenols, mostly anthocyanins, has beentudied by several researchers and it has been shown that they areffected by pH, metal ions, exposure to light, temperature, oxygen,nd enzymatic activities (Bakowska et al., 2003). The stability is anmportant aspect to consider for use of polyphenols as antioxidantsnd colorants in foods.

The stability of polyphenols might be improved using microen-apsulation technologies, such as spray drying (Ersus and Yurdagel,007). Microencapsulation is a technique by which the sensitive

ngredients are packed within a coating or wall material. The wallaterial protects the sensitive ingredients against adverse reaction

nd controls release of the ingredients. In addition, microencapsu-ation can convert liquids into powders, which are easy to handle.

Numerous wall materials or encapsulating agents are availableor food application. Gums arabic, maltodextrins of different dex-rose equivalent (DE), and some proteins are the most commonlysed as wall materials (Shahidi and Han, 1993). Maltodextrins arebtained by acid hydrolysis of several starches (corn, potato orthers). In general, maltodextrins have high solubility in water,ow viscosity, bland flavour, and colorless solutions (Gibbs et al.,999) and are used for encapsulating anthocyanin and phenolicompounds (Ersus and Yurdagel, 2007; Saénz et al., 2009).

An interesting possible encapsulation agent may be inulin, aructooligosaccharide obtained commercially from chicory (Cicho-ium intybus) roots, Dahlia (Dahlia pinuata) and Jerusalem artichokeHelianthus tuberosus). The inulin is composed of fructose unitsith � (2-1) links with glucose at the end of the chain. Inulin

hows prebiotic effects and dietary fibre action and improves cal-ium biodisponibility (Roberfroid, 2000). Inulin is only hydrolyzedn small amounts in the stomach and the large intestine withouthe formation of monosaccharides. Therefore, there is no resul-ant increase in glycemic index, which is important as a potentialngredient for diabetic foods (Roberfroid, 2000).

The objectives of this research were evaluation of polyphenolomposition and content, and antioxidant activity of five blackurrant berries cultivated in Canada. Moreover, the microencapsu-ation by spray drying of polyphenols extracted from black currantomace at pilot plant scale was conducted in order to increase thetability of these bioactive compounds.

. Materials and methods

.1. Chemicals

Citric acid, sodium acetate, sodium hydroxide, methanol (ACSrade), and potassium chloride were purchased from Fisher Sci-

ntific (Ottawa, ON, Canada). Folin–Ciocalteu reagent, gallic acid,otassium persulfate, benzylmercaptan, ABTS, 2,2′-azino-bis(3-thylbenzothiazoline-6-sulfonic acid), and DPPH, 2,2-diphenyl--picrylhydrazyl, was purchased from Sigma (St. Louis, Mo,

ial Crops and Products 34 (2011) 1301– 1309

USA); cyanidin-3-glucoside, cyanidin-3-rutinoside were from Ind-ofine (Hillsborough, NJ, USA). (+)-Catechin, (−)-epicatechin, rutin,quercetin-3-glucoside, kaempferol-3-glucoside, and kaempferol-3-rutinoside were purchased from ChromaDex (Santa Ana, CA,USA). Maltodextrin Maltrin® 10 (9–12 DE), Maltrin® 18 (16.5–19.5DE), and corn syrup solids Maltrin® 21 (20–23 DE) were kindlygift from Grain Processing Corporation (Muscatine, IA). InulinRaftilina® (I) ST (DP > 10) was purchased from Orafti Active FoodIngredients (Oreye, Belgium).

2.2. Black currant material

Ripe black currant berries from 5 varieties (Ben Alder, Ben Tirran,Ben Nevis, Ben Conan, Ben Sarek) were harvested in July 2005 and2006 on Don Smith commercial plantation (Elnora, AB, Canada).Within 2 h after harvest, whole berries were divided into two lotsand stored at −20 ◦C prior to analysis. One lot was used for analysisof polyphenols before storage, and the other for polyphenol analysisafter 9 months of storage at −20 ◦C. For the moisture content deter-mination, fresh berries were ground in a food processor and driedat 110 ◦C until the constant weight was reached. For procyanidinscontent determination fresh berry samples were ground in foodprocessor and freeze-dried. Black currant pomace was obtainedfrom local juice producer.

2.3. Extraction of black currant polyphenols

Alcoholic extraction of black currant polyphenols was per-formed as previously described (Bakowska-Barczak et al., 2007).Briefly, compounds were extracted by homogenizing for 30 s 10 gof frozen fruits in 70 mL of 80% aqueous methanol containing 0.1%formic acid. The mixture was sonicated for 20 min and centrifugedfor 30 min (1000 × g, 4 ◦C). The samples were extracted once morewith 70 mL of 80% aqueous methanol containing 0.1% formic acidusing the same procedure. For spectrophotometric analysis thesupernatants were combined, adjust to the known volume and fil-tered through 0.45 �m filter, while for HPLC analysis the combinesupernatants were evaporated at 40 ◦C under vacuum to removesolvents. The residue was dissolved in water containing 0.1% formicacid and applied to a column of Amberlite XAD-16 nonionic poly-meric absorbent (Rohm and Hass, Philadelphia, USA). After washingwith water containing 0.1% formic acid the polyphenol fraction wascollected by elution with methanol containing 0.1% formic acid andthen evaporated to dryness using a rotary evaporator. The residuewas dissolved with HPLC grade water containing 0.1% formic acid.Three independent extractions were executed.

2.4. Extraction of polyphenols from black currant pomace

The polyphenol compounds were extracted from pomace(35 kg) with 80% aqueous ethanol solution containing 0.5% citricacid at temperature 35 ◦C under vacuum using the DIG-MAZ 50Vacuum Automatic Extractor (SamTech, Mannersdorf, Austria). Theextraction was repeated three times and the alcohol was evapo-rated at 40 ◦C under vacuum inside the extractor. The polyphenolextract was further concentrated inside extractor until 22% of solidcontent was reached. Three independent extractions were exe-cuted.

2.5. Spray drying

The feed mixtures were prepared by mixing polyphenol extract

of black currant (12◦ Brix) with different encapsulating agents untilsolid content of mixtures reached 35◦ Brix. The mixtures were spraydried immediately after preparation in a Niro Mobile Minor 2000spray dryer (GEA Process Engineering Inc., Columbia, MD). The drier

A.M. Bakowska-Barczak, P.P. Kolodziejczyk / Industr

Table 1Drying air temperature for spray drying of black currant polyphenols.

Inlet temperature [◦C] Outlet temperature [◦C]

150 70160 70

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as operated at four different air inlet/outlet temperatures whichre given in Table 1. During drying processes, temperature of theixture was 25 ◦C.The spray dryer was run with water at the fixed operating condi-

ions for 15 min before and after spray drying process. Experimentsere performed in triplicate. The spray dried powders were col-

ected in plastic containers, weighted and stored in desiccatorsontaining silica gel at room temperature.

.6. Powder storage

Spray dried powders were stored in brown bottles with screwaps and placed at 8 ◦C and 25 ◦C for 12 months to determine theffects of temperature and time on the stability of polyphenol com-ounds.

.7. Determination of total polyphenols

The total polyphenols content of the extracts was determinedsing the Folin–Ciocalteu colorimetric method as described byingleton et al. (1999) with modifications. 1 mL of berry extract and

mL of Folin–Ciocalteu reagents were pipetted into a 100 mL volu-etric flask. After 3 min, 10 mL of 20% aqueous solution of sodium

arbonate (Na2CO3) was added, and the flask was brought to vol-me with distilled water. The absorbance at 765 nm was measuredfter 1 h and the results were expressed as mg of gallic acid equiv-lents per 100 g of fresh weight (FW). Data are reported as a meanalue for three measurements.

.8. Determination of antioxidant activity

The antioxidant activity of hydroalcoholic extracts was deter-ined using the Trolox equivalent antioxidant capacity (TEAC) withBTS and DPPH radicals. The TEAC assay with ABTS radical was car-ied out according to Re et al. (1999), while the TEAC with DPPHadical was according to procedure described by Yen and Chen1995). TEAC results are expressed as mM of Trolox equivalents per00 g of FW of black currants or dried powders. Data are reporteds a mean value for four measurements.

.9. HPLC–ESI-MS/MS determination of individual polyphenols

The chromatographic system consisted of a 1100 Series Agilentechnologies LC/MSD system equipped with a diode array detec-or (DAD) coupled to a mass spectrometer (quadrupole analyzer)quipped with an ESI (electrospray ionization) interface (Agilentechnologies, Mississagua, ON, Canada). The reversed-phase sep-ration was performed on a 250 mm × 4.6 mm i.d. RP C18 columnGrace Vydac, Hespedia, CA, USA). The compounds were separatedith gradient elution using 4.5% aqueous formic acid (A) and 80%

cetonitrile in solution A (B) as eluents. The elution system wass follows: 0–7 min 15% B, 7.0–15 min 20% B, 15–16 min 100% B,6–24 min 0.0% B. MS parameters were as follows: capillary volt-

ge, 4000 V; drying gas temperature, 350 ◦C; gas flow (N2) 12 L/min;ebulizer pressure, 60 psi. The instrument was operated both inositive and negative ion mode scanning from m/z 100 to 1500 at

scan rate of 2.0 s/cycle.

ial Crops and Products 34 (2011) 1301– 1309 1303

2.10. Determination of procyanidins content

Procyanidins content in black currants was determined by thethioacidolysis method described by Guyot et al. (2001). Briefly,freeze-dried and grounded samples (30 mg) were dissolved inmethanol and mixed with a 5% solution of benzylmercaptan inmethanol. The vials were sealed and incubated at 40 ◦C for 30 minwith agitation every 10 min and then cooled in an ice bath. Reverse-phase HPLC analyses were performed with an Agilent 1100 liquidchromatograph (Agilent Technologies, Mississagua, ON, Canada)system equipped with diode array detector and the same columnas above. The thioacidolysis products were separated with gradi-ent elution using 2.5% aqueous acetic acid (A) and acetonitrile (B)as eluents. The elution system was as follows: 0 min 3% B, 5 min15% B, 15 min 16% B, 45 min 50% B. Epicatechin and catechin werequantified using external standards of the authentic compounds.Catechin was used as a standard for quantification of epicatechinbenzylthioethers. Data are reported as a mean value for three mea-surements.

2.11. Determination of total anthocyanins content

The total anthocyanins content was measured with the pH dif-ferential method described by Giusti and Wrolstad (2001). Briefly,1 mL of extract was pipetted into two 10 mL volumetric flasks.One of the flasks was brought to volume with potassium chloridebuffer pH 1.0 and the other was diluted to volume with sodiumacetate buffer pH 4.5. The samples were then left in the dark for15 min. The absorbance at �max and 700 nm were measured with anAgilent spectrophotometer (Agilent Technologies, Mississagua, ON,Canada). The results are expressed as cyanidin-3-glucoside equiv-alents per 100 g of fresh weight (FW). Data are reported as a meanvalue ± SD for three measurements.

2.12. Statistical analysis

Statistical analysis was performed using Statgraphic software(StatPoint, Inc., Sainte-Fey, QE, Canada). Data were subjected toone-way analysis of variance for mean comparison, and inter-cultivar significant differences were calculated according to HSDTurkey’s multiple range test. Correlations were calculated on culti-var mean basis, according to Pearson’s test. Differences at P < 0.05were considered to be statistically significant.

3. Results and discussion

The data in Tables 2–4 are presented as a mean value from 2005to 2006 harvest seasons since data obtained in two years were notsignificantly different.

3.1. Total polyphenols content

The results of Folin–Ciocalteu assay are shown in Table 2. ‘BenNevis’ and ‘Ben Conan’ cultivars had the highest gallic acid equiv-alents (741.7 and 721.8 mg/100 g FW, respectively), followed by‘Ben Alder’ and ‘Ben Sarek’ (670.9 and 664.7 mg/100 g FW, respec-tively). The lowest polyphenol content was measured in ‘Ben Tirran’cultivar (623.5 mg/100 g FW, respectively).

A previous report on the phenolic content in black cur-rants showed higher concentration of total polyphenols in fruits,955 mg/100 g FW in average (Bordonaba and Terry, 2008). Moyer

et al. (2002) reported similar concentration of total polyphenols for‘Ben Nevis’ cultivar (815 mg/100 g FW) and lower concentrationof total polyphenols for ‘Ben Conan’ cultivar (498 mg/100 g FW).The differences in analytical methods, extraction procedures and

1304 A.M. Bakowska-Barczak, P.P. Kolodziejczyk / Industrial Crops and Products 34 (2011) 1301– 1309

Table 2The content of dry matter, total polyphenols, and procyanidins and antioxidant activity of black currant cultivars before and after freezing.

Black currant cultivar

Ben Alder Ben Tirran Ben Nevis Ben Conan Ben Sarek

Dry matter (%) 14.8b 15.2b 19.4a 15.7b 14.4bTotal polyphenols (mg/100 g FW)

Before 670.9b 623.5c 741.7a 721.8a 664.7bAfter 660.0b 580.1d 769.4b 717.1a 669.8b

Procyanidins (mg/100 g FW)Before 214.4b 239.4a 189.6b 139.5c 266.7aAfter 215.1b 231.7a 175.7b 120.3c 257.3a

ABTS (mM/100 g FW)Before 4.5a 4.4a 4.3a 3.7b 3.9bAfter 4.5a 4.3a 4.1a 3.5b 3.7b

DPPH (mM/100 g FW)Before 2.4a 2.3a 2.3a 2.1a 2.2a

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After 2.3a 2.1a

alues are mean ± SD of two samples of each cultivar, analyzed individually in tripl

rowing environment may have contributed to the differences inhenolic concentrations between the studies.

.2. Anthocyanins, flavonoids and procyanidins composition andoncentration in black currants

All five cultivars of black currant had similar anthocyanin pro-les. A total of 11 anthocyanins were detected across all blackurrant cultivars. All of them were identified by comparing theirS data with those recently published (Wu et al., 2004).

able 3nthocyanins content in black currant cultivars before and after freezing.

Anthocyanin (mg/100 g FW)

Ben Alder Ben Tirran

Delphinidin-3-glucosideBefore 52.88a 35.71b

After 47.37a 26.44c

Delphinidin-3-rutinosideBefore 157.58a 133.27a

After 151.68a 125.53a

Cyanidin-3-glucosideBefore 28.67a 39.42a

After 22.72a 32.48a

Cyanidin-3-rutinosideBefore 138.81a 121.99a

After 134.58a 110.22a

Petunidin-3-glucosideBefore 2.54a 0.13b

After 2.41a T

Petunidin-3-rutinosideBefore 4.94a 5.67a

After 4.40a 4.93a

Pelargonidin-3-rutinosideBefore 1.09a 1.20a

After 1.48a 1.03a

Peonidin-3-glucosideBefore 2.46a 1.23b

After 1.74b 0.57

Peonidin-3-rutinosideBefore 1.28b 2.94a

After 1.20b 0.86c

Petunidin-3-(6-coumaroyl)-glucosideBefore 2.69b 6.84a

After 3.01b 5.97a

Cyanidin-3-(6-coumaroyl)-glucosideBefore 1.10b 3.02a

After 1.26b 3.39a

TotalBefore 394.04 351.42

After 371.85 311.50

alues are mean ± SD of two samples of each cultivar, analyzed individually in triplicate; T

2.2a 2.0a 2.1a

Different letters within each row represent significance difference (P < 0.05).

In black currant cultivars studied, individual anthocyaninconcentrations varied slightly (Table 3). In four cultivars thedelphinidin-3-rutinoside accounted for the largest percentage ofthe total peak area (around 40%), while cyanidin-3-rutinoside wasthe main anthocyanin in ‘Ben Sarek’ cultivar (38% of total peakarea). ‘Ben Tirran’ and ‘Ben Sarek’ cultivars contained significantlyhigher concentration of acylated anthocyanins (petunidin-3-(6-

coumaroyl)-glucoside and cyanidin-3-(6-coumaroyl)-glucoside)than other black currant cultivars. The high concentration of acy-lated anthocyanins in ‘Ben Tirran’ cultivar was reported before byWu et al. (2004) who determined the anthocyanins composition

Black currant cultivar

Ben Nevis Ben Conan Ben Sarek

40.13b 30.64bc 33.08b33.37b 25.75c 23.31c

119.22b 96.64b 49.20c125.66ab 92.77b 33.10c

28.92a 15.38b 38.18a23.16a 15.62b 24.83a

118.05a 91.86b 61.75b118.18a 88.15b 46.61c

3.97a 3.26a 0.29b3.87a 3.21a 0.18b

3.95b 3.83b 1.84c4.55a 3.62b 1.03c

0.51b 0.62b 0.87b0.84b 0.99a 0.43c

0.64c 1.07b 1.00b2.39a 1.38b 0.67

1.96b 1.59b 1.98b1.67b 1.69b 0.32d

1.43c 2.30b 5.43a1.00cd 1.72c 5.48a

0.56c 1.06b 2.93a0.43c 0.64c 2.55a

319.34 248.25 196.55315.12 235.54 138.51

: trace. Different letters within each row represent significance difference (P < 0.05).

A.M. Bakowska-Barczak, P.P. Kolodziejczyk / Industrial Crops and Products 34 (2011) 1301– 1309 1305

Table 4Flavonoids content in black currant cultivars before and after freezing.

Flavonoid (mg/100g FW) Black currant cultivar

Ben Alder Ben Tirran Ben Nevis Ben Conan Ben Sarek

Myricetin-3-glucosideBefore 11.12a 7.61b 6.91b 6.06b 2.38cAfter 7.11b 3.39c 3.04c 2.88c 1.28d

Myricetin-3-rutinosideBefore 7.88a 4.95b 3.83b 3.80b 5.60aAfter 4.68b 2.90c 2.79c 2.72c 1.91c

Aureusidin-glucosideBefore 0.51a 0.40a 0.54a 0.31a 0.32aAfter 0.39a 0.48a 0.42a 0.30a 0.32a

Quercetin-3-glucosideBefore 3.80a 4.70a 2.56a 2.59a 2.24aAfter 4.38a 4.97a 3.10a 2.10a 2.22a

RutinBefore 1.75c 1.77c 1.31c 1.39c 2.79bAfter 2.94a 2.75a 2.10b 2.35b 3.48a

Kaempferol-3-glucosideBefore 0.83a 0.79a 0.89a 0.75a 0.81aAfter 0.83a 0.72a 0.71a 0.67b 0.72a

Kaempferol-3-rutinosideBefore 1.72a 1.70a 1.93a 1.62b 1.79aAfter 1.80a 1.56b 1.55b 1.45b 1.57b

TotalBefore 27.61 21.92 17.97 16.52 15.93After 21.13 16.77 12.71 11.47 11.50

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alues are mean ± SD of two samples of each cultivar, analyzed individually in tripl

nd concentration in 6 black currant cultivars grown in England.he anthocyanins composition in English black currant fruits wasimilar to that currently found, although the amounts were higherhan presented herein.

Fruit of the ‘Ben Alder’ cultivar in this study had the highestnthocyanins content 394 mg/100 g FW, followed by ‘Ben Tirran’nd ‘Ben Nevis’, 351 and 319 mg/100 g FW, respectively (Table 3).he ‘Ben Sarek’ berries had the lowest anthocyanins content,97 mg/100 g FW. The anthocyanin concentration in black cur-ant cultivars ‘Ben Nevis’, ‘Ben Tirran’, and ‘Ben Alder’ reportedy Wu et al. (2004) was higher that in the present study (587,74, and 562 mg/100 g FW, respectively). Recently Bordonaband Terry (2008) analyzed the anthocyanins content in 17 UK-rown black currant cultivars and reported lower concentrations ofnthocyanins (in the range of 199–83 mg/100 g FW). Attonen andarjalainen (2006) reported comparable concentrations of antho-yanins in five Finnish black currant cultivars (264 mg/100 g inverage). The discrepancy in anthocyanin contents between theour studies may be due to differences in methodology, growingocation and climate, fruit maturity levels and storage conditionsrior to analysis.

Six different conjugates of flavonols myricetin, quercetin,nd kaempferol were found. Previous studies have identified inlack currant fruits glucose, rutinoside (rhamnosylglucose), galac-ose, malonylglucose, and arabinose conjugates of these flavonolsAttonen and Karjalainen, 2006; Sandell et al., 2009). In this study,he fragmentation of compounds in the MSn analysis revealed twoypes of conjugates. The identification of quercetin and kaempferolerivatives was based on comparison of their retention timesnd mass spectrometric data with those of pure standard. Glu-oside and rutinoside of myricetin and auresidin glucoside weredentified on the basis of MS/MS information and data publishedy Määttä et al. (2003). The present data demonstrated thatyricetin derivatives were the dominant flavonols in all cultivars

xcept one (1.9–11.2 mg/100 g), followed by quercetin derivatives1.3–4.7 mg/100 g) and kaempferol derivatives (0.7–1.9 mg/100 g)Table 4). ‘Ben Sarek’ cultivar contained similar levels of myricetinnd quercetin derivatives. In earlier studies, myricetin has been

Different letters within each row represent significance difference (P < 0.05).

reported to be the main flavonol in Finnish black currant varieties(Mikkonen et al., 2001), whereas quercetin was found to be themajor aglycon in the variety Öjebyn (Häkkinen et al., 1999).

This difference may be due to the difficulty in quantifyingmyricetin, as this flavonol is unstable and sensitive to interferencefrom other compounds (Justesen et al., 1998).

The procyanidins concentration in black currants was analyzedby the thiolysis method. Thiolytic degradation of black currantprocyanidins released catechin, (epi)gallocatechin, and epicate-chin as the free flavan-3-ols and epicatechin benzylthioether and(epi)gallocatechin benzylthioether as the flavan-3-ol adducts.

The concentration of procyanidins in black currant berries var-ied from 140 mg/100 g FW for ‘Ben Conan’ to 267 mg/100 g FWfor ‘Ben Sarek’ (Table 2). In earlier study, lower concentrations ofprocyanidins in ‘Ben Alder’, ‘Ben Nevis’, and ‘Ben Tirran’ cultivars(124–166 mg/100 g FW) were reported (Wu et al., 2004).

3.3. Antioxidant activity of black currant

The antioxidant potential of the black currants was determinedon the basis of the scavenging activity of the stable free radicalsDPPH and ABTS (Table 2). ‘Ben Alder’ cultivar which containedthe highest level of polyphenols was characterized by highestantioxidant activity, 4.5 and 2.4 mM/100 g FW, for ABTS and DPPH,respectively. ‘Ben Conan’ showed the lowest antioxidant potentialamong the cultivars tested, 3.7 and 2.1 mM/100 g FW, for ABTS andDPPH respectively. High antioxidant potential of black currant hasbeen reported previously (Ehala et al., 2005) and the high antiox-idant properties of black currants correlated with its high contentof phenolic compounds. Recently, antioxidant potential of blackcurrant cultivars ‘Ben Alder’, ‘Ben Nevis’, and ‘Ben Tirran’ was ana-lyzed (Wu et al., 2004). ‘Ben Alder’ had the highest antioxidantactivity among black currant cultivars which is in agreement with

our results. The antioxidant activity of black currants was higherthan antioxidant potential of Saskatoon berries or purple corn (3.6,1.2 mM/100 g FW with ABTS, respectively) (Bakowska-Barczak etal., 2009).

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.4. Storage stability of black currant polyphenols

Berries, including black currants, are very perishable and areharacterize by a very short shelf life. Fresh black currants are avail-ble only for few weeks in the year, therefore their shelf life can bextended by freezing.

The obtained result with five black currant cultivars studiedhow that the effects of freezing on anthocyanins vary amongultivars. In some black currant cultivars such as ‘Ben Nevis’ nohange in anthocyanins content was observed. In the other cul-ivars a decrease in anthocyanin concentration was detected, inBen Sarek’ and ‘Ben Tirran’ the changes were statistically signif-cant (Table 3). The HPLC analysis of individual anthocyanins intored fruits showed that instability of nonacylated anthocyaninsas mainly responsible for the decrease in total anthocyanins

oncentration in some cultivars. The cultivar dependent stabil-ty of Saskatoon berry anthocyanins during storage was reportedreviously (Bakowska-Barczak and Kolodziejczyk, 2008). In someaskatoon berry cultivars, such as ‘Lee 2’ an 20% increase in antho-yanins content was observed, while in others, such as ‘Success’ 21%ecrease in anthocyanins level was detected. Previously, a 2.5-fold

ncrease in anthocyanins in raspberries after 8 days storage at 20 ◦Cas reported (Kalt et al., 1999). At the same time smaller changes

n anthocyanins content were reported after storage at lower tem-erature (10 ◦C and 0 ◦C). The 23% increase in anthocyanins ofaspberry cultivar ‘Heritage’, and 10% decrease in anthocyanins ofultivar ‘Rubi’ after 9 months of storage at −20 ◦C was reportedreviously (Ancos et al., 2000a). Recently anthocyanin contents ofrozen blueberries were found stable over 3 months of storage at20 ◦C (Lohachoompol et al., 2004).

The total polyphenol concentrations in frozen black currantruits were not affected by storage at −20 ◦C. A slight decrease,ower than 7%, in total phenolics was observed in all cultivars testedTable 2). No significant decrease in total polyphenols in straw-erry ‘Dover’ and ‘Campineiro’ cultivars stored at 6, 16, and 25 ◦C for–3 days was reported before (Cordenunsi et al., 2005). In anothertudy with Spanish raspberries (Ancos et al., 2000b) it was demon-trated that the freezing process had little effect on total phenolicontent during 12 months of frozen storage. Similarly to frozenlack currants in frozen Saskatoon berries the polyphenols con-ent was found to be stable after 9 months (Bakowska-Barczak andolodziejczyk, 2008).

After 9 months of storage at −20 ◦C no significant decrease inavonoids content in five black currant cultivars was observedTable 4). The quercetin glycosides were well preserved in frozenlack currants, since slight increase of their level was observed.

n contrast to quercetin, myricetin contents were significantlyeduced in frozen black currant during 9 months of storage. A slightecrease in kaempferol content in all cultivar tested was detected.reviously, the good stability of quercetin and poor stability ofyricetin in black currants during 9 months of storage at −20 ◦Cas reported (Häkkinen et al., 2000). Another group observed good

tability of quercetin glycosides during apple storage (van der Sluist al., 2005). The one of possible explanation of the increase inuercetin content in stored black currant berries could be thatuercetin glycosides in frozen black currants become more easilyxtractable during storage. This might be due to degradation of celltructures during storage.

Black currant procyanidin contents were not greatly affected bytorage (Table 2). The highest decrease occurred in ‘Ben Conan’ cul-ivar (14%). Good stability of procyanidins during storage at −20 ◦Cas reported previously in frozen Saskatoon berries (Bakowska-

arczak and Kolodziejczyk, 2008).

The freezer storage showed no effect on antioxidant potential oflack currants (Table 2). The data published previously (Häkkinent al., 2000) showed decreases in antioxidant activity of straw-

ial Crops and Products 34 (2011) 1301– 1309

berries after storage at 6, 16, and 25 ◦C for 2–6 days. For applesstored both at refrigerator temperature and under controlled atmo-sphere conditions, no changes in antioxidant activity were detected(van der Sluis et al., 2001). Also antioxidant activity of raspberrieswas not affected during one year storage at −20 ◦C (Ancos et al.,2000b).

3.5. Microencapsulation of black currant polyphenols

The polyphenol extract of black currant (12◦ Brix) was adjustedto 35◦ Brix as a feed solid content with different encapsulatingagents and spray dried at 150, 160, 180 and 205 ◦C air inlet tem-peratures and changes of moisture, anthocyanin and polyphenolcontents of the powders are given in Table 5. For given inlet tem-peratures, measured outlet temperatures are given in Table 1. Itwas shown that increased spray drying temperatures reduced themoisture content of powders and moisture content ranged from 1.8to 3.9%. The anthocyanin contents ranged from 361 to 454 mg/100 gfor powders with maltodextrins and from 296 to 399 mg/100 g forpowders spray dried with inulin. Powders obtained with inulincontained significantly lower level of anthocyanins than powdersdried with maltodextrins. There was no significant effect of dex-trose equivalent of maltodextrins on anthocyanin content in driedproducts. The inlet drying temperature below 180 ◦C did not affectsignificantly the anthocyanin content in the powders. Previously,black carrot anthocyanins were spray dried using maltodextrinswith DE 10, 21, and 29 at 160, 180, and 200 ◦C (Ersus and Yurdagel,2007). Authors found that for systems containing lower DE mal-todextrins (<29), up to the 180 ◦C air inlet temperature can be used.Cai and Corke (2000) also reported that higher drying temperature(>180 ◦C) is not suitable for spray drying of betacyanins.

Similarly to anthocyanins, total polyphenols content in spraydried powders was not affected by DE of maltodextrins. The concen-trations of total polyphenols for powders dried with maltodextrinsranged from 914 to 1251 mg/100 g. The inulin was less effective inencapsulation of black currant polyphenols than maltodextrin. Thetotal polyphenols content in the powders spray dried with inulinranged from 766 to 967 mg/100 g (Table 4). Previously, inulin wasfound less effective than maltodextrin in cactus pear polyphenolsencapsulation (Saénz et al., 2009).

Lower content of polyphenols and anthocyanins in powdersspray dried with inulin has led to lower antioxidant potential ofthese powders (Table 5). There were no significant differences inantioxidant potential of powders spray dried with maltodextrins.

The type of encapsulating agent used during microencapsula-tion of black currant polyphenols showed significant effect on thedrying yield (Table 5). The highest yield (86%) was obtained withmaltodextrin DE 11 at 150 ◦C. The same coating agent gave the high-est yields at all temperatures used. The results revealed that withhigher DE maltodextrins lower spray drying yield can be obtain.The inulin as coating agent showed positive effect on the dryingyields. The yields obtained for powders dried with inulin were nosignificantly lower than for the same dried with maltodextrin DE11.

3.6. Storage stability of microencapsulated polyphenols

The changes in anthocyanin and polyphenol contents, andantioxidant activity of powders spray dried with different mal-todextrins and inulin during storage at 8 and 25 ◦C is shown inFigs. 1 and 2. The total anthocyanin and total polyphenol con-tents of encapsulated powders were decreased by 16–35% and

2–5%, respectively, at the end of 12 months storage period at8 ◦C (Fig. 1). At 25 ◦C storage temperature, loss of total antho-cyanins and total polyphenols was determined as 24–32% and8–11%, respectively (Fig. 2). The inulin has created significantly

A.M. Bakowska-Barczak, P.P. Kolodziejczyk / Industrial Crops and Products 34 (2011) 1301– 1309 1307

Table 5Total anthocyanins (TA) and polyphenols content (TP), antioxidant activity (ABTS, DPPH), moisture content and yield of powders obtained at different drying temperatures.

Carrier Temperature

150 ◦C 160 ◦C 180 ◦C 205 ◦C

TA [mg/100g] DE 11 452.8a (a) 442.2a (a) 454.0a (a) 401.2b (b)DE 18 451.3a (a) 448.3a (a) 450.0a (a) 400.1b (b)DE 21 430.4a (a) 422.9a (a) 408.0b (a) 361.4b (b)Inulin 398.9a (b) 373.3a (b) 315.5b (b) 275.9c (c)

TP [mg/100g] DE 11 1251.4a (a) 1148.8a (a) 1136.9a (a) 913.8b (a)DE 18 1243.0a (a) 1157.7a (a) 1138.9a (a) 934.8b (a)DE 21 1163.5a (a) 1116.6a (a) 1143.9a (a) 921.6b (a)Inulin 967.2a (b) 878.1a (b) 862.3ab (b) 766.1b (b)

ABTS [mM/100g] DE 11 9.3a (a) 9.3a (a) 9.1a (a) 8.0b (a)DE 18 8.9a (a) 8.7a (a) 8.3a (a) 7.4b (a)DE 21 9.1a (a) 8.9a (a) 8.9a (a) 7.6b (a)Inulin 8.0a (b) 7.6a (b) 7.1b (b) 6.6c (b)

DPPH [mM/100g] DE 11 4.5a (a) 3.6b (a) 3.5b (a) 3.1b (a)DE 18 4.1a (a) 3.8a (a) 3.7a (a) 2.8b (a)DE 21 4.2a (a) 3.4b (a) 3.6b (a) 2.6c (ab)Inulin 2.5a (b) 2.4a (b) 2.2a (b) 1.7b (c)

Moisture content [%] DE 11 3.6a (a) 2.6b (b) 2.3b (a) 1.8c (a)DE 18 3.9a (a) 3.9a (a) 2.7b (a) 2.4b (a)DE 21 3.1a (b) 2.9a (b) 2.7a (a) 2.3b (a)Inulin 3.8a (a) 3.1b (b) 2.5c (a) 2.1c (a)

Yield [%] DE 11 86.3a (a) 77.4b (a) 72.6b (a) 55.1c (a)DE 18 77.4a (b) 69.8a (b) 70.7a (a) 24.1b (c)DE 21 54.2a (c) 58.0a (c) 59.0a (b) 26.9b (c)

V ate. D(

mtcasatoit

Inulin 76.3a (b)

alues are mean ± SD of two samples of each cultivar, analyzed individually in triplicP < 0.05).

ore stable microcapsules with anthocyanins and polyphenolshan maltodextrins. Among maltodextrins the maltodextrin DE 11reated more stable microcapsules, than other two maltodextrins,lthough the differences were no significant. Previous research hashown no effect of maltodextrin type on stability of black carrotnthocyanins (Ersus and Yurdagel, 2007). In powders with mal-odextrins stored at 8 ◦C the increase in total polyphenols content

ccurred in the first 6 months. In powders dried with inulin thencrease was observed even after 12 months of storage. Previously,he polyphenols increase was reported for cactus pear polyphenols

Fig. 1. Storage stability of polyphenols encapsulated i

72.4a (a) 67.7a (a) 32.1b (b)

ifferent letters within each row ‘a’ and column ‘(a)’ represent significance difference

powders dried with inulin after 44 days storage at 60 ◦C (Saénz etal., 2009).

Due to good anthocyanins and polyphenols storage stabilitythe stored powders showed good antioxidant potential. More-over, for powders dried with inulin the antioxidant activity remainunchanged after 12 months storage at 8 ◦C, and slightly lower at25 ◦C. Although, the antioxidant activities of inulin powders were

stable after 12 months of storage at both temperatures, the antiox-idant potentials of maltodextrin powders were still higher at theend of storage experiment.

n different DE maltodextrins and inulin at 8 ◦C.

1308 A.M. Bakowska-Barczak, P.P. Kolodziejczyk / Industrial Crops and Products 34 (2011) 1301– 1309

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0 3 6 9 12

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0 3 6 9 12

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00

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anthocy anins polyphenols

HPPDSTBA

ated i

4

mtAdtp

tlcphrptb

A

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A

A

A

B

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Fig. 2. Storage stability of polyphenols encapsul

. Conclusions

In conclusion, black currants are a rich source of polyphenols,ostly anthocyanins and flavonols. The polyphenols concentra-

ions varied considerably within black currant cultivars, with ‘Benlder’ being the richest one. Black currant polyphenols were stableuring 9 month of storage at −20 ◦C. The good stability of bioac-ive compounds of black currants during freezer storage allowsrolonging the storage time of these berries.

For spray drying of black currant polyphenols, higher air inletemperatures (>180 ◦C) caused more polyphenol and anthocyaninosses. Maltodextrins as a wall material gave the highest antho-yanin and polyphenol contents powder at the end of dryingrocess. Spray dried polyphenol powders were characterized byigh storage stability at both temperatures tested. The black cur-ant polyphenol microcapsules described in this study represent aromising food additive for incorporation into functional foods, dueo their antioxidant content and presence of bioactive componentseneficial for human health.

cknowledgments

The support from Alberta Ingenuity Fund, Alberta Value Addedorporation Ltd. and Mr. Don Smith and Ms. Arden Delidais (D’nAardens) is greatly appreciated.

eferences

ncos, B., Ibanez, E., Reglero, G., Cano, M.P., 2000a. Frozen storage effects on antho-cyanins and volatile compounds of raspberry fruit. J. Agric. Food Chem. 48,873–879.

ncos, B., Gonzales, E.M., Cano, M.P., 2000b. Ellagic acid, vitamin A, and total phenoliccontents and radical scavenging capacity affected by freezing and frozen storagein raspberry fruit. J. Agric. Food Chem. 48, 4565–4570.

ttonen, M.J., Karjalainen, R.O., 2006. High-performance liquid chromatographyanalysis of black currant (Ribes nigrum L.) fruit phenolics grown either conven-tionally or organically. J. Agric. Food Chem. 54, 7530–7538.

akowska, A.M., Kucharska, A.Z., Oszmianski, J., 2003. The effects of heating, UV irra-

diation and storage on stability of anthocyanin-polyphenol copigment complex.Food Chem. 81, 349–355.

akowska-Barczak, A.M., Kolodziejczyk, P., 2008. Evaluation of Saskatoon berry(Amelanchier alnifolia Nutt.) cultivars for their polyphenol contents, antioxidantproperties, and storage stability. J. Agric. Food Chem. 56, 9933–9940.

DE 21 Inulin

n different DE maltodextrins and inulin at 25 ◦C.

Bakowska-Barczak, A.M., Marianchuk, M., Kolodziejczyk, P., 2007. Survey of bioac-tive components in Western Canadian berries. Can. J. Physiol. Pharmacol. 85,1139–1152.

Bakowska-Barczak, A.M., Lee, Y.-Y., Hong, S.-H., Kolodziejczyk, P., 2009. Antho-cyanins: their role, processing and application. In: Kozlowski, R., Zaikov, G.,Pudel, F. (Eds.), Renewable Resources: Obtaining, Processing and Applying. NovaScience Publishers, Inc., New York, pp. 129–145.

Bordonaba, J.G., Terry, L.A., 2008. Biochemical profiling and chemometric analysis ofseventeen UK-grown black currant cultivars. J. Agric. Food Chem. 56, 7422–7430.

Cai, Y.Z., Corke, H., 2000. Production and properties of spray-dried amaranthus beta-cyanin pigments. J. Food Sci. 65, 1248–1252.

Cordenunsi, B.R., Genovese, M.I., Nascimento, J.R.O., Hassimoto, N.M.A., Santos,R.J., Lajolo, F.M., 2005. Effects of temperature on the chemical compositionand antioxidant activity of three strawberry cultivars. Food Chem. 91, 113–121.

Ehala, S., Vaher, M., Kaljurand, M., 2005. Characterization of phenolic profiles ofnorthern European berries by capillary electrophoresis and determination oftheir antioxidant activity. J. Agric. Food Chem. 53, 6484–6490.

Ersus, S., Yurdagel, U., 2007. Microencapsulation of anthocyanin pigments of blackcarrot (Daucus carota L.) by spray drier. J. Food Eng. 80, 805–812.

Gibbs, B.F., Kermasha, S., Alli, I., Mulligan, C.N., 1999. Encapsulation in the foodindustry: a review. Int. J. Food Sci. Nutr. 50, 213–224.

Giusti, M.M., Wrolstad, R.E., 2001. Anthocyanins characterization and measurementwith UV-visible spectroscopy. In: Wrolstad, R.E. (Ed.), Current Protocols in FoodAnalytical Chemistry, 1st ed. John Wiley & Sons, New York.

Guyot, S., Marnet, N., Sanoner, P., Drilleau, J.F., 2001. Direct thiolysis on crude applematerials for high-performance liquid chromatography characterization andquantification of polyphenols in cider apple tissues and juices. Methods Enzy-mol. 335, 57–70.

Häkkinen, S., Kärenlampi, S., Heinonen, M., Mykkänen, H., Törrönen, R., 1999. Con-tent of the flavonols quercetin, myricetin, and kaempferol in 25 edible berries.J. Agric. Food Chem. 47, 2274–2279.

Häkkinen, S.H., Kärenlampi, S.O., Mykkänen, H.M., Törrönen, A.R., 2000. Influence ofdomestic processing and storage on flavonol contents in berries. J. Agric. FoodChem. 48, 2960–2965.

Han, X., Shen, T., Lou, H., 2007. Dietary polyphenols and their biological significance.Int. J. Mol. Sci. 8, 950–988.

Jing, P., Bomser, J.A., Schwartz, S.J., He, J., Magnuson, B.A., Giusti, M.M., 2008.Structure–function relationships of anthocyanins from various anthocyanin-rich extracts on the inhibition of colon cancer cell growth. J. Agric. Food Chem.56, 9391–9398.

Justesen, U., Knuthsen, P., Leth, T., 1998. Quantitative analysis of flavonols, flavones,and flavanones in fruits, vegetables and beverages by high-performance liquidchromatography with photodiode array and mass spectrometric detection. J.Chromatogr. A 799, 101–110.

Kalt, W., Forney, C.F., Martin, A., Prior, R.L., 1999. Antioxidant capacity, vitamin C,

phenolics, and anthocyanins after fresh storage of small fruits. J. Agric. FoodChem. 47, 4638–4644.

Liu, S., Manson, J.E., Lee, I.M., Cole, S.R., Hennekens, C.H., Willet, W.C., Buring, J.E.,2000. Fruit and vegetable intake and risk of cardiovascular disease: the Women’sHealth Study. Am. J. Clin. Nutr. 72, 922–928.

ndustr

L

M

M

M

M

N

R

R

R

S

A.M. Bakowska-Barczak, P.P. Kolodziejczyk / I

ohachoompol, V., Srzednicki, G., Craske, J., 2004. The changes of total anthocyaninsin blueberries and their antioxidant effect after drying and freezing. J. Biomed.Biotechnol. 5, 248–252.

äättä, K.R., Kamal-Eldin, A., Törrönen, A.R., 2003. High-performance liquid chro-matography (HPLC) analysis of phenolic compounds in berries with diode arrayand electrospray ionization mass spectrometric (MS) detection: Ribes species. J.Agric. Food Chem. 51, 6736–6744.

artin, A., Cherubini, A., Andres-Lacueva, C., Paniagua, M., Joseph, J.A., 2002. Effectsof fruits and vegetables on levels of vitamins E and C in the brain and theirassociation with cognitive performance. J. Nutr. Health Aging 6, 392–404.

ikkonen, T.P., Määttä, K.R., Hukkanen, A.T., Kokko, H.I., Törrönen, A.R., Kärenlampi,S.O., Karjalainen, R.O., 2001. Flavonol content varies among black currant culti-vars. J. Agric. Food Chem. 49, 3274–3277.

oyer, R., Hummer, K., Finn, C., Frei, B., Wrolstad, R.E., 2002. Antocyanins, phenolics,and antioxidant capacity of diverse small fruits: Vaccinium, Ribes and Rubus. J.Agric. Food Chem. 50, 519–525.

eto, C.C., 2007. Cranberry and blueberry: evidence for protective effects againstcancer and vascular diseases. Mol. Nutr. Food Res. 51, 652–664.

amos, S., 2008. Cancer chemoprevention and chemotherapy: dietary polyphenolsand signalling pathways. Mol. Nutr. Food Res. 52, 507–526.

e, R., Pellegrini, N., Proteggente, A., Pannala, A., Yang, M., Rice-Evans, C., 1999.Antioxidant activity applying an improved ABTS radical cation decolorizationassay. Free Radic. Biol. Med. 26, 1231–1237.

oberfroid, M., 2000. Inulin-Type Fructans: Functional Food Ingredients. CRC Press,Boca Raton, Florida.

aénz, C., Tapia, S., Chávez, J., Robert, P., 2009. Microencapsulation by spray drying ofbioactive compounds from cactus pear (Opuntia ficus-indica). Food Chem. 114,616–622.

ial Crops and Products 34 (2011) 1301– 1309 1309

Sandell, M., Laaksonen, O., Järvinen, R., Rostiala, N., Pohjanheimo, T., Tiitinen, K.,Kallio, H., 2009. Orosensory profiles and chemical composition of black cur-rant (Ribes nigrum) juice and fractions of press residue. J. Agric. Food Chem. 57,3718–3728.

Seeram, N.P., Momin, R.A., Nair, M.G., Bourquin, L.D., 2001. Cyclooxygenaseinhibitory and antioxidant cyanidin glycosides in cherries and berries. Phy-tomedicine 8, 362–369.

Shahidi, F., Han, X.-Q., 1993. Encapsulation of food ingredients. Crit. Rev. Food Sci.Nutr. 33, 501–547.

Singleton, V.L., Orthofer, R., Lamuela-Raventos, R.M., 1999. Analysis of totalpolyphenols and other oxidation substrates and antioxidants by means ofFolin–Ciocalteu reagent. Methods Enzymol. 299, 152–178.

Soobrattee, M.A., Bahorun, T., Aruom, O.I., 2006. Chemopreventive actions ofpolyphenolic compounds in cancer. Biofactors 27, 19–35.

Tsuda, T., Ueno, Y., Yoshikawa, T., Kojo, H., Osawa, T., 2006. Microarray profiling ofgene expression in human adipocytes in response to anthocyanins. Biochem.Pharmacol. 71, 1184–1197.

van der Sluis, A.A., Dekker, M., de Jager, A., Jongen, W.M.F., 2001. Activity and con-centration of polyphenolic antioxidants in apple: 3. Effect of cultivar, harvestyear, and storage conditions. J. Agric. Food Chem. 49, 3606–3613.

van der Sluis, A.A., Dekker, M., van Boekel, M.A.J.S., 2005. Activity and concentrationof polyphenolic antioxidants in apple juice. 2. Stability during storage. J. Agric.Food Chem. 53, 1073–1080.

Wu, X., Gu, L., Prior, R.L., McKay, S., 2004. Characterization of anthocyanins andproanthocyanidins in some cultivars of Ribes, Aronia, and Sambucus and theirantioxidant capacity. J. Agric. Food Chem. 52, 7846–7856.

Yen, G., Chen, H., 1995. Antioxidant activity of various tea extracts in relation to theirantimutagenicity. J. Agric. Food Chem. 43, 27–32.