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Changes in Carotenoids, Ascorbic Acids, andQuality Characteristics by the Pickling of Paprika(Capsicum Annuum L.) Cultivated in KoreaJihyun Park, Suna Kim, and BoKyung Moon

Abstract: Paprika (Capsicum annuum L.) is widely used as a healthy vegetable having antitumor-promoting activity andreducing or preventing chronic disease. Paprika has been mostly consumed as fresh fruit, and as food colorants such as oleo-resin or pigment powder. In this study, pickled paprika was produced and its quality characteristics were monitored duringstorage (35 ◦C for 42 d). Carotenoid composition, ascorbic acid, total phenolic contents, and antioxidant activities werealso analyzed. Five carotenoid compounds were identified in the pickled paprika and after 42 d of storage, total carotenoidcontent was 2.44 ± 0.69 mg/100g fresh weight(fw) and ascorbic acid content was 50.90 ± 3.26 mg/100g dry weight (dw).2,2′-azino-di-(3-ethylbenzthiazoline sulphonate (ABTS) radical-scavenging activity of the pickled paprika was maintainedabove 70% until 28 d of storage, and then decreased to 47% of the initial activity. pH increased from 2.78 ± 0.06 to3.10 ± 0.03 at 14 d and was then maintained until 42 d. Soluble solids increased gradually and color values including L∗,a∗, and b∗ decreased during storage. Hardness also decreased from 6.17 ± 0.18 kg force to 1.90 ± 0.60 kg force duringstorage. The overall taste of the pickled paprika was deemed to be good until 28 d of storage. Pickled paprika showeda possibility as a new pickled product. We demonstrated that paprika could be processed as a new pickled product withextended storage.

Keywords: ascorbic acid, carotenoids, pickled paprika, quality characteristics, storage

Practical Application: Pickled paprika was produced and its quality characteristics along with phytochemical contents weremonitored during storage. Phytochemicals, including ascorbic acid and polyphenols in pickled paprika were considerablyretained and visual color was satisfactory during storage. Texture was deemed to be satisfactory for 4 wk. Considering thatour experiment was performed at a relatively high temperature and without the addition of calcium for the improvementof texture, our results are quite promising in order to produce new pickled products with extended shelf-life along withconserving nutritional and functional components and satisfying consumer needs.

IntroductionFresh paprika (Capsicum annuum L.) is widely eaten as a healthy

vegetable having antitumor-promoting activity (Maoka and others2001, 2004) and reducing or preventing chronic diseases such ascardiovascular diseases (Aizawa and others 2009). Its biologicalactivities are caused by various phytochemicals such as carotenoids,ascorbic acid, flavonoids, and phenolic compounds (Jeong andothers 2006; Al-Duais and others 2009). In particular, capsanthinand capsorubin, which are unique to red paprika, have shownantioxidative and antitumor activities (Kim and others 2009).

Paprika has been mostly consumed as fresh fruit, and as foodcolorants such as oleoresin or pigment powder. In South Korea,the consumption of fresh paprika has increased 6-fold in 3 y, withan approximate 3-fold increase in cultivation area in 7 y (Jeong andothers 2008). Moreover, increases in dining out have led to the use

MS 20110460 Submitted 4/10/2011, Accepted 6/6/2011. Authors Park andMoon are with Dept. of Food and Nutrition, Chung-Ang Univ., Anseoung-siGyeonggi-do, 456–756, Korea. Author Kim is with Food and Nutrition in HomeEconomics, Korea National Open Univ., 169 Dongsung-Dong, Jongno-Gu, Seoul,110–791, Korea. Direct inquiries to author Moon (E-mail: bkmoon@cau.ac.kr).

of dried paprika as a healthy ingredient in processed foods suchas frozen pizza, hamburgers, and so on (Papageorge and others2003; Jeong and others 2006; Al-Duais and others 2009), and theconsumption of processed paprika has also increased. However,paprika is not yet processed in various forms for proper usage.

Pickling has been traditionally used for the storage of vari-ous vegetables such as cucumbers, radishes, and eggplants (Palma-Harris and others 2002; Sesena and others 2002; Lee and others2005; Yoo and others 2006), thus maintaining nutritional compo-nents as well as improving texture and enhancing flavor by lacticacid fermentation. Recently, vinegar, the main ingredient in pick-ling, has received attention as a functional food ingredient for bodyweight control (Rastmanesh 2011). Therefore, newly introducedfoods and cuisines to Western countries offer various pickled veg-etables that are more numerous than in the past (Shin and others2006). However, the usage of paprika as a processed food is slightlylimited because of quality deterioration during storage and shortshelf-life.

Most research on paprika or red peppers has focused on har-vesting and drying (Almela and others 1991; Cremer and Eich-ner 2000; Mınguez-Mosquera and others 2000; Perez-Galvez andothers 2006; Gallardo-Guerrero and others 2010). In the aspectof processing paprika, a few studies are available on pretreatments

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such as blanching, high-pressure treatments, freezing, proceduresfor acidified canned pimiento (Flora and others 1978; Castro andothers 2008), and factors influencing texture retention of salt-free,acidified red bell pepper during storage (Papageorge and others2003).

Fresh red paprika is known to be rich in phytochemicals suchas various carotenoids, vitamin C and E, and flavonoids (Lee andothers 1995; Mınguez-Mosquera and others 2000; Amakura andothers 2002; Materska and Perucka 2005; Topuz and Ozdmir2007), and in a previous study, the phytochemicals compositionand the antioxidant activity of red paprika cultivated in Korea (Kimand others 2011) were determined. However, there is still limitedinformation on changes in phytochemicals during the process-ing of paprika, therefore, changes in phytochemicals during thepickling process were investigated. The color and texture of veg-etables are negatively affected by acidification and thermal process-ing such as blanching (McGlynn and others 1993, Lau and others2000), as well as the destruction of vitamins C and the degradationof carotenoids (Ladron de Guevara and others 2002). However,blanching, vinegar (acetic acid), and salt are major factors thatcontribute to the improvement of microbial safety of pickled veg-etables (Shin and others 2006). Therefore, both aspects must beconserved during the pickling process of red paprika.

In this research, aiming to produce a pickled paprika as a newpickled product to provide nutritious compounds and dietary fiberand to increase the storage stability of paprika, the quality charac-teristics of pickled red paprika during storage were monitoredby measuring pH, brix◦, color values, and hardness, and alsoperformed sensory evaluations. Carotenoid composition, ascor-bic acid and total phenolic contents, and antioxidant activities ofthe pickled paprika were also analyzed.

Materials and Methods

Samples and equipmentRed paprika fruits (RP) (C. annuum L., Var. Special) were har-

vested on the 12 October 2008. All samples were kindly providedby Nongsan Trading Co. (Kimje, Chonbuk, Korea). All chro-matographic analyses were performed using a high performanceliquid chromatography (HPLC) apparatus equipped with a PU-2089 pump, auto sampler, and an ultraviolet and refractive index89 (RI) detector (Jasco, Tokyo, Japan). A V530 UV/VIS spec-trophotometer (Jasco) and VS-5000N centrifuge (Vison ScientificSeoul, Korea) were also used.

ChemicalsCapsanthin, capsorubin, lutein, zeaxanthin, α- and β-

cryptoxanthin, and α- and β-carotene were purchased from Chro-maDex (Irvine, Calif., U.S.A.). L-ascorbic acid was purchased fromSigma-Aldrich (St. Louis, Mo., U.S.A.). HPLC-grade acetonitrile,methanol (MeOH), ethanol (EtOH), and water were purchasedfrom Burdick & Jackson (SK Chemicals, Ulsan, Korea). All otherchemicals were purchased from Sigma-Aldrich.

Preparation of pickled paprikaThe optimum recipe for the pickling solution, size, and pre-

treatment conditions for the paprika were decided by preliminaryexperiments and references (Papageorge and others 2003). Thepaprika was washed, drained, and then the stems and seed vesselswere removed. Edible parts of the paprika were cut into 2 × 2 cm.The cut pieces of the paprika were blanched in water at 75 ◦C for1 min and placed in sterilized jars (200 mL), and then preheated

pickling solution was added to the jars at a ratio of 1:1 (w/v).The composition of the pickling solution (%) is listed in Table 1.The jars after bottling were sterilized in boiling water for 4 minand then cooled at room temperature. Samples were stored in anincubator at 35 ◦C for 42 d in the absence of light and analyzedevery 2 wk.

Carotenoid analysisCarotenoids were analyzed using a previously described method

of Kim and others (2011). For carotenoid analysis, extraction wasperformed with acetone until the color had completely disap-peared. The pickled paprika (2 g) was extracted in 20 mL ofacetone at 4 ◦C for 24 h in the dark. The acetone extract (10mL) was incubated with 2 mL of 30% KOH/MeOH at 37 ◦C for18 h in the dark, and extracted 3 times with diethyl ether. Thecombined extract was then washed several times with distilledwater until neutral, and 10 mL of 10% NaCl and 10 mL of 2%Na2SO4 were added to remove the hydrophilic phase. After evap-orating the collected extracts, the residue was dissolved in acetoneand stored at −20 ◦C under nitrogen until used. The HPLC (Jasco,Tokyo, Japan) was equipped with a Model PU980 pump, a ModelUV 975 detector, and a Model 807-IT integrator. The wave-length was set at 450 nm, and an XTerra RP C18 column (250 ×4.6 mm, 5μm; Waters, Milford, Mass., U.S.A.) set to 450 nm and35 ◦C. The mobile phases consisted of 15% water/MeOH (v/v) (a)and 50% acetone/MeOH (v/v) (b) at a flow rate of 1.5 mL/min.The gradient system was initially 100% A, 55% A/45% B for 20min, back to 100% A for 6 min, to 100% B for 7 min, to 100% Afor 9 min, and finally to 100% A for 5 min, for a total duration of47 min.

Ascorbic acid analysisAscorbic acid analysis was performed using the method of Food

Code (KFDA 2004). A freeze-dried pickled paprika sample (25 g)was mixed with 50 mL of 4% metaphosphoric acid. Ascorbic acidwas then extracted by shaking at 4 ◦C for 1 h, followed by centrifu-gation for 10 min at 4000 rpm. The supernatant was filtered usinga 0.45-mm PVDF syringe filter (Whatman, Maidstone, U.K.) anddiluted with 4% metaphosphoric acid. The HPLC (Jasco) wasequipped with a Model PU980 pump, a Model UV 975 detec-tor, and a Model 807-IT integrator. The wavelength was set at450 nm, and an YMC-Pack Polyamine II column (4.6 × 250mm, 5 μm; YMC) set at 254 nm and 40 ◦C. HPLC was con-ducted using the mobile phase consisted of acetonitrile and 40 mMmetaphosphoric acid (70:30, v/v) at a flow rate of 1 mL/min.

Table 1–Composition of pickling solution (%).

Composition (%)

Water 16.65Vinegar (acetic acid) 25.40High fructose corn syrup 50.00D-Sorbitol 5.00Salt 1.00MSG 0.02Disodium succinate 0.03Succinic acid 0.20Sodium polyphosphate 0.30Ascorbic acid 0.70Citric acid 0.30Malic acid 0.30Dill flavor 0.10

MSG = monosodium glutamate.

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Determination of total phenolic contentTotal phenolic content was determined using Folin–Ciocalteu

reagent (Velioglu and others 1998). The Folin–Ciocalteu reagentwas diluted 2-fold in deionized water. A freeze-dried pickledpaprika sample (1 g) was mixed with 10 mL of 80% EtOH (v/v)at room temperature for 20 min, followed by centrifugation for10 min at 4000 rpm. The extract solution (0.25 mL) was mixedwith 0.75 mL of diluted Folin–Ciocalteu reagent and 2 mL ofNa2CO3 (2.0%, w/v), and then incubated at 36 ◦C for 30 min.Absorbance was measured at 750 nm using a UV–VIS spectropho-tometer. The results were expressed as milligrams of catechinequivalents per gram of dry weight (mg CE/g dw).

Determination of antioxidant activityThe 2,2′-azino-di-(3-ethylbenzthiazoline sulphonate) (ABTS)

radical-scavenging activity of the pickled paprika was measured asdescribed previously (Arnao and others 2001). For the measure-ment of antioxidant activity, freeze-dried pickled paprika (0.3 g)was extracted with 3 mL of 80% EtOH (v/v) at room temperaturefor 20 min (Miller and others 1996). All radical solutions werefreshly prepared each day. The inhibition percentage of ABTSradical was calculated as: (1 − [Absorbance of sample/Absorbanceof control]) × 100.

Moisture content, pH, and soluble solidsMoisture contents were determined using 1 g of homogenized

picked paprika that was dried until a constant weight at 105 ◦C toquantify the dry matter (adapted from AOAC 1990). The pickledpaprika was homogenized with Ultra Turrax T25 basic Staufen,IKA) (IKA, Staufen, Germany) and centrifuged at 4500 × g for20 min. The supernatant was analyzed as follows. The pH wasmeasured at 20 ◦C with a pH meter 430 (Corning, Mass., U.S.A.).The pickled paprika was homogenized with Ultra Turrax T25basic and soluble solids content was determined at 20 ◦C with arefractometer (RA-250WE, KEM, Kyoto, Japan) and reported as◦Brix.

Texture analysisThe texture of the pickled paprika was quantified using a Tex-

ture Profile Analyzer (TPA) (TAHDi/500, Stable Micro System,Godalming, U.K.). A pickled paprika sample (size of 2 cm × 2cm × 0.5 cm) was placed on the test plate. A probe (Stable Mi-cro System Probe Nr 36) was used to measure the hardness ofthe sample. All measurements were conducted at room temper-ature and were performed on the skin side of the paprika tissue.The flat base, on which the sample was placed, moved downwardto the plunger (Yoo and others 2006). The instrumental condi-tions of the texture analyzer for the pickled paprika are listed inTable 2.

Table 2– Instrumental conditions of texture analyzer for pickledpaprika.

Measurement Condition

Graph type TPAProbe SMS P/36Test speed 10.0 mm/sPosttest speed 10.0 mm/sStrain 50%Time 1.00 s

TPA = texture profile analyzer.SMS P/36 = stable micro system probe nr 36.

Color valuesThe colors of the pickled paprika samples were measured ob-

jectively using a Hunter’s Lab color measurement device (HunterColor Ultra Scan PRO, Hunter Associates Laboratory, Reston,Va., U.S.A.). The Hunter color values L∗, a∗, and b∗ were mea-sured. �E∗

ab indicates the degree of color difference between twosamples. The color difference (�E∗) was calculated as follows:

�E∗a b =

√(�L∗)2 + (�a ∗)2 + (�b ∗)2

Sensory evaluationAffective tests to evaluate color, appearance, flavor, texture,

sweetness, paprika flavor, and overall taste of the pickled paprikawere performed using a 7-point scale method. Thirty panelistswererecruited from graduate students at the department of Food andNutrition in Chung-Ang University. A structure scale was usedto score all the attributes. One indicated very bad, 4 indicatednormal, and 7 indicated very good. Coded samples identified by3-digit random numbers were presented to the panelists in ran-dom order. Samples were evaluated every 2 wk during the 42 dof storage.

Statistical analysisQuantitative data were expressed as means and standard devi-

ations (SD) of at least 3 measurements. Each experimental setwas compared with one-way analysis of variance (ANOVA) andTukey’s test (P < 0.05) using SAS version 8.0 for Windows (SASInst., Cary, N.C., U.S.A.).

Results and Discussion

Changes of phytochemicals in pickled red paprikaAs shown in Table 3, 5 carotenoid compounds were identified

in the pickled paprika at 0 d of storage. In agreement with previ-ous studies (Mınguez-Mosquera and others 2000; Sun and others2007; Kim and others 2011), capsanthin and β-carotene were de-tected as main carotenoids with contents of 7.72 ± 0.35 mg/100gfw and 6.60 ± 5.16 mg/100g fw, respectively, comprising about90% of total carotenoids. It is worth nothing that capsanthin com-prised about 50% of the total carotenoids in contrast to previousresearch (Kim and others 2011), in which about 80% of capsanthinwas revealed. This might be due to differences in the sensitivityof each carotenoid during processing including preheating in hightemperature, dehydration, and acidification (Gallardo-Guerreroand others 2010).

Capsorubin, which is a unique carotenoid along with capsan-thin found in Capsicum spp., and lutein and zeaxanthin, which areyellow pigments found in various fruits and vegetables (Daviesand others 1970; Perry and others 2009) were also identi-fied. Changes in carotenoids in the pickled red paprika during42 d of storage at 35 ◦C were also investigated (Table 3). Cap-santhin remained the most abundant carotenoid during storage,even though the total content decreased to 1.62 mg/100g. Themain reason for carotenoid deterioration is oxidation caused bytheir high degree of unsaturation and sensitivity to light, heat,and oxygen (Rodriguez-Amaya 1999, Varon and others 2000).Total carotenoid content was decreased to about 34% of initialcontent just after 14 d of storage and reached final content of2.44 ± 0.69 mg/100g fw after 42 d of storage. In particular,β-carotene was reduced to about 80% from its initial content.

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At 0 d of storage, capsorubin content was 0.71 ± 0.31 mg/100gfw, which comprised about 4.6% of the total carotenoid contents,while zeaxanthin and lutein together represented only 1% of to-tal carotenoids. However, the ratio of capsorubin and capsanthin,increased to 80% of the total carotenoids at 42 d of storage. Itmeant that carotenoids of red pigment, including capsorubin andcapsanthin, were retained more than other carotenoids. This resultwas in accordance with the report that capsanthin decomposedmore slowly than the other carotenoids, and its radical-scavengingeffects last longer (Matsufuji and others 1998).

Ascorbic acid is one of the most well-known antioxidant (Arnaoand others 2001) and red paprika is a great source of this compound(Kim and others 2011). The acid was the most effective contributorto paprika antioxidant activity compared to phenolic compounds.Changes in ascorbic acid and phenolic compounds by pickling redpaprika was reported in Table 4. At the 1st day of pickling, ascorbicacid in the pickled red paprika was 85.90 ± 1.03 mg/100g dw andwas retained during 14 d of storage without a statistical difference(P < 0.05). Ascorbic acid at 42 d of storage was 50.90 ± 3.26 mg/100g dw, which was about 59% of the ascorbic acid content at0 d of storage, indicating that ascorbic acid was less destroyedin the pickling process compared to carotenoids. Total phenoliccontent did not statistically change in the 42 d as shown in Table 4(P < 0.05). It meant that phytochemicals in pickled paprika wereconsiderably retained during storage. The antioxidant activity ofthe pickled red paprika was measured by ABTS radical-scavengingactivity, which is the most effective method for the measurementof antioxidant activity in paprika (Kim and others 2011). During28 d of storage, the antioxidant activity of the pickled red paprikawas maintained above 70%, and then decreased to 47% of theinitial activity. This result demonstrated that ascorbic acid contentwas positively correlated with antioxidant activity (R2 = 0.89).

Quality changes in pickled red paprikaChanges in pH values and soluble solids of the pickled red

paprika during storage are shown in Table 5. pH increased from2.78 ± 0.06 to 3.10 ± 0.03 over 14 d and was then maintaineduntil 42 d. Generally, pickled vegetables produce lactic acid duringfermentation causing a decrease in pH (Shin and others 2006; Yooand others 2006; Mcfeeters and Perez-Dıaz 2010). However, thepickled paprika did not show any significant changes in pH duringstorage, because in this study, lactic acid fermentation was not themain process to produce the pickled product. Generally, the pHof fresh paprika has been reported in the range of 2.8 to 4.8(Papageorge and others 2003; Castro and others 2008), and thepH of the pickling solution used in this experiment was 1.07 ±0.05. Therefore, our results for pH change during storage mighthave been mainly caused by the osmotic pressure of the picklingsolution and paprika fruit. For shelf-stable-pickled vegetables, theCode of Federal Regulations (21 CFR part 114) states that acidor acid ingredients must be added to maintain the pH at or below4.6, and that a heat treatment must be included in the process toprevent the growth of microbial pathogens (Shin and others 2006).

Therefore, the pickled red paprika produced in this study wouldappear to be safe as a shelf-stable-pickled vegetable.

Soluble solids increased gradually during storage and reached28.37◦Brix after 42 d of storage. Before the pickling process, sol-uble solids in the pickling solution and in the red RP were at48.8 ± 0.17◦Brix and 6.01 ± 0.01◦Brix, respectively (data notshown), which is in accordance with the results of Castro andothers (2008). Some studies reporting that salt, sorbitol, and highfructose corn syrup concentration were the most significant fac-tors as osmotic agents (Ozen and others 2002; Ozdemir and others2008), this finding might be caused by osmotic pressure and thedecomposition of the initial tissue by acidification (Papageorgeand others 2003).

The color values and hardness of pickled red paprika was shownin Table 6. Color changes during storage were calculated fromchanges in L∗, a∗, and b∗ (Kim and others 2008) and expressed as�E∗ values.

All color values including L∗, a∗, and b∗ decreased during stor-age. Color change in the 1st 2 wk appeared remarkably as �E∗= 12.58, and the subsequent were 1.40 and 6.37, respectively.�E∗

ab indicates the degree of color difference between two sam-ples. �E∗

ab value in the range of 0 to 0.5 signifies an imperceptibledifference in color between two samples, 0.5 to 1.5 a slight differ-ence, 1.5 to 3.0 a just noticeable difference, 3.0 to 6.0 a markeddifference, 6.0 to 12.0 an extremely marked difference, and above12.0 a color of a different shade (Kim and others 2008). Therefore,remarkable color change seemed to happen in the 1st 2 wk of stor-age. This result was in accordance with the change of carotenoidcontents that decreased more in 1st 2 wk.

Hardness also decreased from 6.17 ± 0.18 kg force to 1.90 ±0.60 kg force during storage, even though hardness was retainedabove 50% of the initial value for 28 d of storage. Some reports statethat a reduction in hardness might be related to tissue softeningcaused by enzymatic and/or nonenzymatic cell wall degradation,and the addition of calcium or sulfite can prevent softening of acidfruits (Papageorge and others 2003; Mcfeeters and others 2004).In this experiment, enzyme has been already inactivated by heattreatment before bottling. Therefore, the observed reduction ofhardness in our experiment might have been caused by nonenzy-matic degradation of cell wall components during storage.

Table 4–Contents of ascorbic acid and total phenolics, and antioxi-dant activity in pickled paprika during storage at 35 ◦C.

Ascorbic Total phenolicacid contents

Storage (mg/ (mg CE/ ABTS(d) 100g dw) 100g dw) (%)

0 85.90 ± 1.03aa 240 ± 9.22a 82.39 ± 0.78a14 82.66 ± 4.76a 241 ± 6.20a 71.62 ± 0.78b28 62.60 ± 2.77b 240 ± 11.7a 68.97 ± 0.36b42 50.90 ± 3.26c 242 ± 22.8a 38.97 ± 0.73caValues are means ± SD of triplicate determinations, and different letters within the samecolumn mean statistically different at P < 0.05.

Table 3–Carotenoid composition and contents (mg/100g fw) of pickled paprika during storage at 35 ◦C.

Storage (d) Capsorubin Capsanthin β-Carotene Lutein +zeaxanthin Total carotenoid

0 0.71 ± 0.31aa 7.72 ± 0.35a 6.60 ± 5.16a 0.15 ± 0.08a 15.18 ± 5.9a14 0.51 ± 0.28a 3.75 ± 1.69b 0.84 ± 0.18a 0.07 ± 0.07a 5.17 ± 2.22b28 0.37 ± 0.35a 1.67 ± 0.28b 0.65 ± 0.08a 0.03 ± 0.003a 2.72 ± 0.71b42 0.32 ± 0.09a 1.62 ± 0.33b 0.47 ± 0.26a 0.03 ± 0.01a 2.44 ± 0.69baValues are means ± SD of triplicate determinations, and different letters within the same column mean statistically different at P < 0.05.

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Table 5–Changes in moisture contents, pH, and soluble solids in pickled paprika during storage at 35 ◦C.

Storage (d)parameters 0 14 28 42

Moisture (%) 53.24 ± 0.62a 52.96 ± 0.37a 53.28 ± 2.03a 54.81 ± 1.33apH 2.78 ± 0.06ba 3.10 ± 0.03a 3.11 ± 0.05a 3.12 ± 0.04aSoluble solids (Brix◦) 21.26 ± 0.38d 24.47 ± 0.35c 27.23 ± 0.47b 28.37 ± 0.31aaValues are means ± SD of triplicate determinations, and different letters within the same row mean statistically different at P < 0.05.

Table 6–Changes in color and hardness in pickled paprika during storage at 35 ◦C.

Storage Color values Hardness(d) L∗ a∗ b∗ �E∗ (kg force)

0 36.18 ± 0.96aa 38.30 ± 0.76a 23.73 ± 0.75a 6.17 ± 0.18a14 32.48 ± 0.63b 29.0 ± 1.66b 16.10 ± 1.26b 12.58 5.23 ± 0.73ab28 32.20 ± 1.28b 27.62 ± 1.85b 16.08 ± 1.18b 1.40 4.90 ± 0.98b42 28.86 ± 1.59c 22.36 ± 1.84c 14.74 ± 1.87b 6.37 1.90 ± 0.60caValues are means ± SD of triplicate determinations, and different letters within the same column mean statistically different at P < 0.05.

Table 7–Sensory evaluations of pickled paprika during storage at 35 ◦C.

Storage time (d)

0 14 28 42

Color 4.60 ± 1.59aa 4.60 ± 1.12a 5.13 ± 1.41a 4.75 ± 1.71aAppearance 5.20 ± 1.42a 4.73 ± 1.44a 4.60 ± 1.35a 4.00 ± 2.16aFlavor 4.87 ± 1.19a 4.60 ± 0.99a 4.60 ± 0.99a 4.25 ± 0.96aTexture 4.86 ± 0.99a 5.00 ± 1.03a 3.67 ± 1.07b 1.75 ± 1.07cSweetness 5.13 ± 1.30a 4.13 ± 1.30ab 4.13 ± 1.30ab 3.00 ± 1.83bPaprika flavor 5.07 ± 1.33a 4.93 ± 1.03a 3.87 ± 1.30a 2.75 ± 1.71bOverall taste 4.20 ± 0.91b 5.53 ± 0.77a 4.60 ± 1.24b 1.75 ± 0.96caValues are means ± SD of triplicate determinations, and different letters within the same row mean statistically different at P < 0.05.

The results of sensory evaluation were shown in Table 7. Therewere no significant differences in sensory scores for color and ap-pearance, even though carotenoid contents were decreased duringstorage. It seemed that the decreasing degree of carotenoids shownin this result did not affect the perception of visual color. The tex-ture of the pickled paprika showed its highest score at 14 d ofstorage and decreased rapidly after 28 d of storage. Because overalltaste revealed a similar tendency with texture, it was thought thattexture might be the most important characteristics, even thoughsweetness and paprika flavor also could affect the consumer prefer-ences for pickled paprika. The overall taste of the pickled paprikawas considered to be good until 28 d of storage.

ConclusionsPickled paprika was produced and its quality characteristics

along with phytochemical contents were monitored during stor-age. Phytochemicals such as ascorbic acid and polyphenols wereretained to some degree, and even though total carotenoids con-tent decreased, visual color and texture were satisfactory in sensoryevaluations for 4 wk. In this study, we demonstrated that phyto-chemicals such as ascorbic acid and polyphenols were retained tosome degree, and visual color was satisfactory in sensory evalua-tions even though total carotenoid content had decreased. Texturewas also satisfactory for 4 wk. Considering that this experimentwas performed at a relatively high temperature and without theaddition of calcium for the improvement of texture, the resultsgathered in this research showed the possibility that pickled pa-prika could be used as new pickled products with extended shelf-life along with conserving nutritional and functional componentsand satisfying consumer needs.

AcknowledgmentsThis study was supported by a grant from the Rural Develop-

ment Administration and by the Agricultural R&D Promotion

Center, Ministry of Food, Agriculture, Forestry and Fisheries,Republic of Korea.

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