J Korean Soc Food Sci Nutr 한국식품영양과학회지 44(8), 1212~1218(2015) http://dx.doi.org/10.3746/jkfn.2015.44.8.1212 저온및재래식공정에따른쌀 야채류압출성형물의항산화활성비교 안상희 류기형 공주대학교식품공학과 Comparison of Antioxidant Activities of Extruded Rice with Vegetables by Cold and Conventional Extrusion Sang-Hee An and Gi-Hyung Ryu Department of Food Science and Technology, Kongju National University ABSTRACT The study was designed to investigate the effects of cold and conventional extrusion on antioxidant properties of extruded rice with vegetables. Moisture content and screw speed were fixed at 25% and 150 rpm. Cold extrusion and conventional extrusion were adjusted at die temperature of 80 C with a CO 2 injection rate of 300 ml/min and 140 C without a CO 2 injection, respectively. Pumpkin, tomato, strawberry, and green tea powder of 10% were individually blended with rice flour. 1,1-Diphenyl-2-picrylhydrazyl radical-scavenging activity of extruded pumpkin and tomato mix by conventional extrusion was higher than that by cold extrusion. Total phenolic content in extruded pumpkin, tomato, and strawberry mix by cold extrusion was higher than that by conventional extrusion. Total flavonoid content was highest (18.82 mg/g) in extruded green tea by conventional extrusion. Total carotenoid content decreased in extruded pumpkin but increased in extruded tomato. Tomato extrudates with cold extrusion had higher lycopene content than conventional extrusion. Anthocyanin content of conventional extruded strawberry was higher than that of cold extrudates. Total chlorophyll contents decreased through the extrusion process. Key words: extruded rice with vegetables, cold extrusion, conventional extrusion, antioxidant activity 서 최근식품산업의발전과식생활의변화로항암, 항산화등기능성을가지고있는컬러푸드에대한관심이증가하면서식물성식품소재를활용하기위한개발과천연물이가지는기능성을식품에접목시키는연구가진행되고있다. 과일류및채소류등은 phenol류, 비타민 C 및 flavonoid, anthocyan, 카로티노이드등의항산화성분을갖는천연식물자원으로알려져있다 (1). 특히단호박은회복기의환자, 위장이약한사람, 산후부종제거등에좋은식품으로많이알려져있으며, 비타민 A, 카로티노이드류, Ca, Na, P 등의영양소와섬유질이풍부한건강식으로소비가증가하고있다 (2). 토마토는전세계적으로널리소비되고있는식물자원으로주성분은수분이며비타민 A, B 및 C와섬유질, 칼슘, 식이섬유가풍부하게들어있다. 라이코펜은카로티노이드와함께중요한천연항산화성물질이며, 과피에다량함유되어있는페놀물질은전립선암예방에효과적이다. 이러한 Received 12 May 2015; Accepted 6 July 2015 Corresponding author: Gi-Hyung Ryu, Department of Food Science and Technology, Kongju National University, Chungnam 32439, Korea E-mail: ghryu@kongju.ac.kr, Phone: +82-41-330-1484 론 생리활성물질들은항암작용, 고혈압, 비만과다이어트등의다양한효능을나타낸다 (3,4). 딸기는비타민 C, quercetin, caffeic acid, flavonol류및페놀화합물등의다양한항산화물질이함유되어있으며, 항암물질의활성화및산소라디칼의제거등과관련된항산화효과가우수하다. 이러한성분의효능때문에과실류와채소류중가장많이소비된다 (5,6). 녹차는폴리페놀류, 섬유질, 단백질, 탄수화물, 유리당, 지방및무기질등으로구성되어있고폴리페놀은녹차성분중건량의 20~35% 로가장많이함유되어있으며, 대부분 catechin으로알려진 flavonol류다. 이러한기능성성분들은혈압및혈중콜레스테롤저하, 항균, 항암작용등항산화효과와다양한생리활성이있는것으로알려져있다 (7). 압출성형공정은온도, 압력, 전단에의해혼합, 분쇄, 가열, 성형, 건조와같은단위조작이단시간에가공되는연속공정으로다른열처리가공공정과비교하여경제적이며효율적인공정이다 (8). 일반적인압출성형공정은 100 C 이상에서수분의상변화를통해팽화가일어나는반면에 CO 2 주입압출성형공정은수분의상변화대신 CO 2 의압력차에의한비체적변화로 100 C 이하에서도팽화가가능하다. 또한재래식압출성형공정보다낮은전단력으로스크루마모율감소와에너지투입량이낮다 (9). 압출성형독립변수인
저온및재래식압출성형쌀 야채류의항산화활성비교 1213 수분함량, 스크루회전속도, 사출구의구조, 스크루배열등을조절하여다양한특성을가지는제품을생산할수있다 (10). 이러한압출성형공정의특성을이용하여플레이크나에너지바 (bar) 제조등이이루어지고있으며, 곡류압출성형물의물리적특성에관한연구가발표되었다 (11-13). 현재까지저장온도에따른야채류의성분변화, 야채류첨가에따른쿠키및케이크제조등의품질특성과생리활성성분분석등에대한연구가이루어지고있으며 (1,5,7, 14), 온도와수분함량에따른곡류압출성형물의물리적특성비교및저온압출성형현미 야채류의물리적특성연구가보고되었다 (11,13,15). 위와같이야채류를이용한성분분석및수분과온도에따른곡류와야채류압출성형물의물리적특성변화에대한연구는다수발표되었으나저온및재래식압출성형공정을통한야채류압출성형물의항산화활성비교에대한연구는진행되지않았다. 따라서본연구는단호박, 토마토, 딸기, 녹차를원료로압출성형을통하여저온및재래식압출성형에따른 DPPH(1,1-diphenyl-2-picrylhydrazyl) 라디칼소거능, 총페놀, 총플라보노이드, 총카로티노이드, 라이코펜함량, 안토시아닌및총클로로필등의항산화활성의변화를알아보았다. 재료및방법재료압출성형물제조를위한쌀은충남아산신통정미소에서정미한 2013년도혼합쌀을 9월에도정하여사용하였다. 단호박, 토마토, 딸기, 녹차분말은가루나라 (Seoul, Korea) 에서구입하여사용하였으며, 쌀과야채류혼합원료는야채류분말을 10% 로배합하였다 (15). 원료의일반성분은 Table 1에나타내었으며, AOAC법 (16) 에따라수분함량은 105 C 상압건조법, 조회분은직접회화법, 조지방은 Soxhlet 추 출법, 조단백은 Ninhydrin법 (17) 으로정량하였다. 압출성형압출성형물의제조에사용된압출성형기는자체제작한실험용쌍축압출성형기 (THK31T, Incheon Machinery Co., Incheon, Korea) 를사용하였으며스크루배열은 Fig. 1과같다. 스크루직경은 30.0 mm이며, 길이와직경의비 (L/D ratio) 는 23:1이었고, 사출구는원형으로직경이 3.0 mm인것을사용하였으며, 원료사입량은 100 g/min으로고정하였다. 수분함량은 25%, 스크루회전속도는 150 rpm 으로고정하였다. 저온압출성형은사출구온도가 80 C, CO 2 주입은 3.0 MPa에서 300 ml/min으로조절하였다. 한편재래식압출성형은사출구온도 140 C로조절하였으며 CO 2 주입은하지않았다 (15). 압출성형공정을거쳐제조된압출성형물은열풍건조기 (DS-FCPO250, Dongseo Sci. Co., Seoul, Korea) 에서 50 C로건조하여물리적특성연구에사용하였고, 가정용분쇄기 (FM-681, Hanil, Haman, Korea) 로분쇄하여직경이 0.5 mm 이하인체를통과한분말을분석시료로사용하였다. 추출물의제조압출성형물은유용성분을추출하기위하여 Kim 등 (18) 의방법을수정하여추출하였다. 시료 1 g에 70% 메탄올 20 ml를가하고 24시간동안 30 C의 shaking incubator에서 130 rpm으로추출한다음 3,000 rpm으로 20분간원심분리한후상등액을 0.2 μm nylon filter로여과하여 DPPH 라디칼소거능, 총페놀함량및총플라보노이드함량을측정하는추출물로사용하였다. DPPH 라디칼소거능전자공여능또는라디칼소거능은 DPPH를사용하여측정하였다. 추출물 0.2 ml에 0.1 mm DPPH를 0.8 ml 첨가 Table 1. Proximate compositions of rice with vegetables Material 1) Proximate component (%) Moisture content Crude ash Crude fat Crude protein Carbohydrate 2) Rice Pumpkin mix Tomato mix Strawberry mix Green tea mix 13.50±0.16 15.80±0.01 15.66±0.08 16.16±0.01 15.24±0.03 0.70±0.14 0.81±0.02 0.61±0.30 0.70±0.21 0.97±0.03 0.31±0.01 1.42±0.14 0.92±0.33 0.67±0.16 1.26±0.14 5.52±0.10 4.70±0.23 5.65±0.29 4.63±0.45 3.53±1.83 2) Total carbohydrate was calculated by removing moisture content, crude ash, crude fat, and crude protein. 79.97±0.13 77.27±0.08 77.16±0.07 77.84±0.65 79.00±1.96 Fig. 1. Screw configuration for extruded rice with vegetables (Model THK 31T).
1214 안상희 류기형 하여 30분간실온에서반응시킨후 UV/VIS Spectrophotometer(Libra S12, Biochrom Ltd., Cambridge, UK) 를사용하여 520 nm에서흡광도를측정하였다. DPPH에의한 radical-scavenging activity는아래와같은식 (1) 을이용하여계산하였다 (18). Scavenging activity (%) = Absblank-Abs sample Abs blank 100 (1) Abs blank 는 70% 메탄올을사용하여측정한흡광도값이고, Abs sample 은추출물의흡광도값이다. 총페놀함량총페놀성화합물함량은 Folin-Ciocalteu 비색법 (19) 을수정하여측정하였으며, tannic acid를표준물질로사용하여표준곡선을작성하였다. 즉 0.5 ml의추출물에 10배희석한 Folin-Ciocalteu's phenol reagent(sigma-aldrich Co., St. Louis, MO, USA) 1.5 ml를첨가하여 5분간반응시킨다음 6% 의 Na 2CO 3 1.5 ml를첨가하여암소에서 90분동안반응시킨후 765 nm에서흡광도값을측정하였다. 총플라보노이드함량압출성형물의총플라보노이드함량은 Ko 등 (20) 의방법을수정하여측정하였다. 추출물 0.5 ml에증류수 3.2 ml 와 5% NaNO 2 0.15 ml를가한다음 5분후 10% AlCl 3 6H 2O 0.15 ml를가하여 1분간방치하고 1 M NaOH 1 ml 를가한후흡광도값을 510 nm에서측정하였다. 표준물질은 quercetin을사용하여표준곡선을작성하였다. 총카로티노이드함량단호박과토마토압출성형물의총카로티노이드함량은 Hwang 등 (21) 의방법을수정하여측정하였다. 시료 0.5 g 에 acetone 5 ml를넣고실온에서 40분동안교반한후 Whatman No. 2 filter paper(whatman International Ltd, Cambridge, UK) 를사용하여여과한다음 450 nm에서흡광도를측정하였다. 총카로티노이드함량은 β-carotene을이용하여작성한표준곡선으로부터함량을구하였다. 라이코펜함량라이코펜함량은 Javanmardi와 Kubota(22) 의방법에따라측정하였다. 시료 1 g을알루미늄호일을감싼 PTFE test tube에넣고 lycopene 추출용액 (hexane : 0.05% butylated hydrotoluene/acetone : ethanol=1:1:1) 39 ml를각시험관에첨가하여 10분동안교반한후상온에서 15분동안방치하였다. 상층액 ( 헥산층 ) 은 UV/VIS Spectrophotometer(Libra S12, Biochrom Ltd.) 를이용하여 503 nm 에서흡광도를측정한후아래의식 (2) 에의하여라이코펜함량을환산하였다. Lycopene (mg/kg)=(x/y) A 503 3.12 (2) 여기서 x는 hexane(ml) 의양을나타내고 y는시료의무게 (g) 이며, A 503 은 503 nm에서의흡광도값이고 3.12는정지계수를나타낸다. 안토시아닌함량안토시아닌함량은 Seo 등 (23) 의방법을사용하였다. 시료 1 g에 0.1% HCl이포함된 methanol 10 ml를가하여 3시간동안 25 C에서 150 rpm으로추출한후 3,000 rpm으로 20분간원심분리한상등액을안토시아닌분석시료로사용하였다. 위추출물 1 ml에 0.025 M potassium chloride buffer(ph 1.0) 1 ml와 0.4 M sodium acetate buffer(ph 4.5) 1 ml를각각혼합하여반응액의흡광도값을 510 nm와 700 nm에서측정하였다. 총안토시아닌함량은 cyanidin-3-glucoside의몰흡광계수 (ε=26,900 M -1 cm -1 ) 를이용하여아래의식 (3) 에의해산출하였다. Anthocyanin content (mg/l)= A MW 1,000 (3) ε V A (absorbance)=(a 510-A 700) ph1.0-(a 510-A 700) ph4.5 MW (molecular weight of cyanidine-3-glucoside)= 449.2 ε=26,900 M -1 cm -1 V= 추출물의부피 클로로필함량클로로필함량은 Lee 등 (24) 과 Lim 등 (25) 의방법을수정하여측정하였다. 시료 10 mg에 80% cold acetone 1 ml를가하여 5분간교반추출후원심분리한상등액을 645 nm와 663 nm에서흡광도를측정하였으며, 아래의식 (4) 에따라클로로필함량을계산하였다. Chlorophyll a (mg/l)=12.72 OD 663-2.58 OD 645 (4) Chlorophyll b (mg/l)=22.88 OD 645-5.50 OD 663 Total chlorophyll (mg/l)=7.22 OD 663+20.3 OD 645 통계처리 통계분석은 SPSS 통계프로그램 (Statistical Package for the Social Science, ver. 12.0, SPSS Inc., Chicago, IL, USA) 을이용하여통계분석하였으며, 각실험군은평균과표준편차로나타내었다. 각군의결과값에대해유의수준 P<0.05에서 Duncan's multiple range test를실시하였다. 결과및고찰 DPPH 라디칼소거능 DPPH 라디칼소거능은플라보노이드류및기타페놀성
저온및재래식압출성형쌀 야채류의항산화활성비교 1215 물질에대한항산화활성의지표이며, 천연물의수용성또는유기용매추출물의항산화활성에널리사용되는측정법이다 (5,26). 저온및재래식압출성형공정에따른쌀 야채류압출성형물의 DPPH 라디칼소거능은 Table 2와같다. 압출성형물의 DPPH 라디칼소거능은저온녹차압출성형물이 87.94% 로가장높았고, 저온딸기압출성형물이 30.74% 로가장낮았다. 단호박및토마토를첨가한압출성형물의 DPPH 라디칼소거능은저온압출성형공정보다재래식압출성형공정에서더높게측정되었으나딸기및녹차압출성형물은저온및재래식공정에따른유의적인차이는나타나지않았다. 또한단호박과토마토압출성형물은압출성형무처리구보다압출성형처리구의 DPPH 라디칼소거능이증가하였는데, 이는압출성형공정시발생되는고온및전단력등에의해생리활성물질이증가되었다고판단된다. Kim 등 (18) 은과채류를열처리하였을때 DPPH 라디칼소거능의증가는열처리로인한마이야르반응이일어나항산화활성을가진마이야르반응물질 (MRPs) 인 xylose와 lysine MRPs 와같은새로운화합물이 DPPH 라디칼소거능을나타낸다고하였다. 생성된다양한 MRPs 물질의 hydroxyl기가항산화효과에중요한역할을하며, 그밖에 fructose와 glucose 등아미노산의 MRPs는 polyphenoloxidase를저해하여자유라디칼제거능과관련된것으로보고된바있다 (27). 총페놀함량페놀성화합물은식물계에널리분포하는항산화물질로서다양한구조와분자량을가지며, polyphenolic 화합물들의분자내 phenolic hydroxyl기가단백질, 효소단백질등과결합하는성질에의해항산화, 항암및항균등의다양한생리활성을나타낸다 (28). 압출성형물의총페놀함량은 Table 2에나타내었다. 녹차를첨가한저온압출성형물이 116.52 mg/g으로가장높았고, 딸기를첨가한저온압출성형물이 3.62 mg/g으 로가장낮았다. 단호박, 토마토및딸기를첨가한압출성형물은압출성형후총페놀함량이증가하였으며, 저온압출성형물보다재래식압출성형물에서총페놀함량이다소높았다. 녹차첨가압출성형물은다른압출성형물에비해총페놀함량이높게나타났는데이는다른야채류압출성형물에비해녹차자체에함유되어있는페놀함량이높기때문이며, 식품을열처리하면가공중식물체속페놀성분등의천연비효소적항산화물질이활성화된다고보고된바있다 (7,27). 압출성형후총페놀함량의변화는단백질과결합된고분자의페놀성화합물이압출성형공정으로인한고온고압처리에의해조직이파괴되어불용성성분으로부터단백질의가수분해등으로인해폴리페놀성분이유리되었기때문에총페놀함량이증가된것으로판단된다 (18). 총플라보노이드함량총플라보노이드는자연계에존재하는페놀류의화합물로대부분당과결합된배당체형태로존재하며, 노란색또는적자색을띠는색소화합물로유리기를소거하거나연쇄반응을종결시켜항산화능을나타낸다 (26). 저온및재래식압출성형공정에따른쌀 야채류압출성형물의총플라보노이드함량은 Table 2에나타내었다. 녹차를첨가한재래식압출성형물이 18.82 mg/g으로가장높았으며, 단호박을첨가한재래식압출성형물이 0.24 mg/g으로가장낮았다. 단호박, 토마토및딸기압출성형물보다녹차압출성형물의총플라보노이드함량이높았는데이는다른야채류에비해녹차자체에함유되어있는플라보노이드성분이많기때문으로사료된다. 압출성형후총플라보노이드함량이감소한것은압출성형으로인해용출된유효성분이저분자화되면서생성된화합물중에확인되지않은활성성분 (26) 에의하여감소되었거나열처리에의해플라보노이드물질이감소된것으로사료된다 (5,29). 열처리에의한총플라보노이드함량감소를규명하기위해서는정성분석과같은추가적인연구가필요할것으로판단된다. Table 2. Antioxidant activity of extruded rice with vegetables Feed material Extrusion type Pumpkin mix Tomato mix Strawberry mix Green tea mix DPPH radical scavenging activity (%) 29.72±2.97 g2) 40.38±0.74 f 48.08±0.25 e 52.45±0.25 d 55.33±0.37 c 62.15±0.37 b 29.83±0.60 g 30.74±0.17 g 31.59±0.69 g 87.06±0.01 a 87.94±0.25 a 87.67±0.12 a 2) Values of different letters in the same column are significantly different (P<0.05). Total phenolic compound (TAE mg/g) 7.34±0.11 g 8.85±0.42 f 9.29±0.21 f 10.58±0.41 e 11.13±0.35 de 11.65±0.29 d 3.00±0.29 i 3.62±0.07 hi 4.09±0.02 h 124.66±0.10 a 116.52±0.21 b 101.08±0.82 c Total flavonoid (mg/g) 0.98±0.07 de 0.44±0.11 ef 0.24±0.01 f 1.19±0.19 d 0.45±0.01 ef 0.55±0.03 ef 0.51±0.04 ef 0.47±0.04 ef 0.35±0.01 f 23.06±0.18 a 17.73±0.53 c 18.82±0.60 b
1216 안상희 류기형 본실험결과총플라보노이드의함량은총페놀함량에비해미량함유되었는데, 이는페놀이플라보노이드계화합물을포함하는큰범주이기때문이며플라보노이드계화합물을제외한페놀성분이증가한것으로판단된다 (30). 총카로티노이드함량카로티노이드계열의색소는항산화활성이뛰어난천연생리활성물질로동맥경화억제, 심장질환및성인병예방등다양한효능을나타내고자연계에서불안정한구조로존재하여온도, 빛및산소등에의해영향을받으며, 추출, 분쇄및저장등의가공에의해산화되거나이성질화될수있다 (31). 단호박및토마토를첨가한압출성형물의총카로티노이드함량은 Table 3과같다. 저온단호박압출성형물이 36.13 μg/g으로가장높았으며저온토마토압출성형물이 19.66 μg/g으로가장낮았다. 단호박을첨가한압출성형물은압출성형후총카로티노이드함량이낮아졌으나토마토압출성형물은증가하였다. 카로티노이드는불포화도가매우크기때문에가열산화및자동산화등에약하여감소가일어난다고알려져있으며, Shin 등 (32) 은호박분말의카로티노이드함량이가열및열풍건조로인하여현저하게감소가일어났다고보고하였다. 토마토압출성형물의총카로티노이드의증가는압출성형공정시발생되는고온고압에의하여토마토조직구조가파괴되어라이코펜함량이증가되었기때문으로판단된다 (33). 라이코펜함량토마토에함유되어있는카로티노이드중항산화활성이뛰어난라이코펜은체내에흡수되면비타민 A로전환되는 β-카로틴과 α-카로틴, 루테인등을함유하고있으며, 항산화작용을가지는항산화제로알려져있다 (3). 토마토를첨가한저온및재래식압출성형물은압출성형후라이코펜함량이증가하였으며, 저온압출성형물보다재래식압출성형물이 7.17 mg/kg으로높았다 (Fig. 2). 이는압출성형공정의전단력과고온에의해라이코펜과조직행렬사이의약한표면결합이파괴되어추출용매에대한용해도가증가되었기때문에압출성형물의라이코펜함량이증가되었다고판단된다 (33). 토마토라이코펜의생리활성은가열처리 Table 3. Total carotenoid contents of extruded rice with pumpkin and tomato Feed material Pumpkin mix Extrusion type Total carotenoid contents (μg/g) 132.95±1.66 a2) 36.13±0.15 b 31.86±0.64 c 6.50±0.04 f Tomato 19.66±0.40 e mix 23.54±0.08 d 2) Values of different letters are significantly different (P<0.05). Lycopene contents of rice. with tomato (mg/kg). 8 7 6 5 4 3 2 1 0 Lycopene c b Conventional extrusion Fig. 2. Lycopene contents of rice with tomato. Values represent the mean of triplicate measurements of analyzed sample. Different letters (a-c) above the bars indicate statistically significant differences at P<0.05. 에영향을받으며, 토마토를가공이나가열하면생체이용률이높은 cis형라이코펜으로전환되고 cis형라이코펜은온도에따라증가한다고보고하였다 (3,33). 안토시아닌함량딸기에함유되어있는안토시아닌화합물은페놀화합물중하나로적색, 자색등을나타내는색소이며산소라디칼제거, 산화적스트레스로인한세포변형억제등항산화효과가우수하다 (6). 딸기압출성형물의안토시아닌함량은 Table 4와같다. 재래식압출성형물이 0.28 mg/l로저온압출성형물보다안토시아닌함량이높았으나유의적인차이는나타나지않았다. 압출성형후안토시아닌함량은감소하였다. Lee와 Park(34) 의비열처리구에비해열처리구의안토시아닌색소구성성분이감소한결과와일치하였다. 가열에의한안토시아닌함량의변화는안토시아닌색소가열에민감하여가공시열처리로인한색소의파괴가일어났기때문으로판단된다 (5). 클로로필함량클로로필은식물체에널리분포하는녹색색소로기상및환경조건등에따라함량이다르며카로티노이드와함께단백질또는지단백질과결합한상태로상처치료효과, 세균생육저지, 조혈작용등의생리활성을가지며항산화성및항암성이보고되고있다 (35). 녹차압출성형물의클로로필 a와 b의함량비는거의비슷하거나클로로필 b의함량이높게나타났다 (Table 5). Table 4. Anthocyanin contents of extruded rice with strawberry Feed material Extrusion type Anthocyanin (mg/l) 1.72±0.01 a2) Strawberry 0.23±0.09 b mix 0.28±0.07 b 2) Values of different letters are significantly different (P<0.05). a
저온및재래식압출성형쌀 야채류의항산화활성비교 1217 Table 5. Chlorophyll contents of extruded rice with green tea (mg/l) Feed material Extrusion type Chlorophyll a Chlorophyll b Total chlorophyll Green tea mix 1.94±0.03 a2) 0.61±0.01 b 0.62±0.02 b 2) Values of different letters in the same column are significantly different (P<0.05). 1.13±0.03 a 0.69±0.01 b 0.71±0.01 b 3.07±0.06 a 1.33±0.04 b 1.33±0.01 b 압출성형후녹차압출성형물의총클로로필함량은감소하였으며클로로필 a, b 및총클로로필은저온및재래식공정에따른유의적인차이는없었다. 열처리로인해클로로필함량이감소한본실험결과는 blanching에의한열처리로총클로로필함량이감소한 Jung 등 (36) 의연구결과와유사하였다. 녹차에함유된클로로필은가열공정시클로로필일부가페오피틴, 페오필린등으로분해되어클로로필함량및비율이달라졌다고판단된다 (37). 결론적으로저온및재래식압출성형은쌀 야채류의항산화활성변화에영향을미친다. 재래식압출성형공정은단호박및토마토를첨가한압출성형물의 DPPH 라디칼소거능을증가시키며, 저온압출성형공정은단호박및토마토압출성형물의페놀함량을증가시킨다. 저온압출성형공정보다재래식에서토마토의라이코펜함량이증가하였다. 야채류의종류에따라저온및재래식공정의조건을달리하면높은항산화활성을갖는식품소재로이용할수있으며, 압출성형쌀 야채류는소비자의건강지향적욕구에따른기능성소재로써활용될수있는가치가있을것으로판단된다. 요약본연구는저온및재래식압출성형공정에따른쌀 야채류압출성형의항산화활성에대해분석하였다. 압출성형조건은수분함량 25%, 스크루회전속도 150 rpm으로고정하였다. 저온압출성형조건은사출구온도 80 C, CO 2 주입량 300 ml/min, 재래식압출성형은사출구온도 140 C, CO 2 0 ml/min으로조절하였다. 원료는쌀분말에단호박, 토마토, 딸기및녹차분말을각각 10% 씩혼합하여사용하였다. 단호박및토마토첨가한압출성형물의 DPPH 라디칼소거능은저온압출성형공정보다재래식압출성형공정에서더높았다. 단호박, 토마토및딸기를첨가한압출성형물은압출성형후총페놀함량이증가하였으며, 저온압출성형물보다재래식압출성형물에서총페놀함량이다소높았다. 총플라보노이드함량은녹차를첨가한재래식압출성형물이 18.82 mg/g으로가장높았다. 압출성형후단호박을첨가한압출성형물의총카로티노이드함량은낮아졌으나토마토압출성형물은증가하였다. 토마토압출성형물의라이코펜함량은압출성형후증가하였으며, 재래식압출성형에서더높았다. 딸기압출성형물의안토시아닌함량은저온압출성형보다재래식압출성형공정에서높았다. 압출성형후녹차압출성형물의총클로로필함량은감소하였으며클로로필 a, b 및총클로로필은저온및재래식공정에따른유의적인차이는없었다. 감사의글 본연구는한국연구재단에서시행한이공분야기초연구사업 (2014R1A1A4A03004018) 의연구비지원에의해수행된과제의일부로이에감사드립니다. REFERENCES 1. Paik J, Kim S, An H, Joo N. 2013. Processing optimization and antioxidant activity of chiffon cake prepared with tomato powder. J Korean Diet Assoc 19: 1-13. 2. Kim SR, Ha TY, Song HN, Kim YS, Park YK. 2005. Comparison of nutritional composition and antioxidative activity for Kabocha squash and pumpkin. Korean J Food Sci Technol 37: 171-177. 3. Kim HS, Chin KB. 2011. Physico-chemical properties and antioxidant activity of pork patties containing various tomato powders of solubility. Korean J Food Sci Ani Resour 31: 436-441. 4. Na Y, Joo N. 2012. Processing optimization and antioxidant activity of sausage prepared with tomato powder. Korean J Food Cookery Sci 28: 195-206. 5. Gam LS. 2013. Effect of heat treatment on the antioxidant activities and quality characteristics of strawberries. MS Thesis. Gyeongsang National University, Jinju, Korea. 6. Kim YA. 2008. Effects of strawberry powders on the quality characteristics of yellow layer cake. Korean J Food Cookery Sci 24: 536-541. 7. Choi GN, Jeong CH, Kim JH, Kwak JH, Shin YH, Lee SC, Cho SH, Choi SG, Heo HJ. 2009. Effect of storage temperature an water activity on antioxidant activities of powdered green tea extracts. Korean J Food Preserv 16: 333-341. 8. Lee GH. 2011. Extrusion characteristics for the snack of corn flour using twin-screw extruder. J Agric Life Environ Sci 23: 47-52. 9. Gu BJ, Ryu GH. 2012. Effect of die geometry and carbon dioxide injection on physical properties of extruded corn flour. Food Eng Prog 16: 83-91. 10. Lee JK, Im BS, Ryu GH. 2006. Changes in paste viscosity of extruded buckwheat by extrusion process variables. Food Eng Prog 10: 92-99. 11. Kim CH, Tie J, Ryu GH. 2012. Effects of moisture content on physical properties of extruded cereal flours. J Korean Soc Food Sci Nutr 14: 1603-1610. 12. Tie J, Park HY, Ryu GH. 2005. Characteristics of cereals prepared by extrusion-cooking and freeze-drying. Korean J Food Sci Technol 37: 757-762. 13. Tie J, Yu JH, Ryu GH. 2012. Effect of moisture content
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