Molecular Structure and Lipid in Starches for Mook

묵 제조용 전분의 분자구조와 지방질

Mook, a traditional gel food in Korea, has been made from mainly acorn, buckwheat, and mungbean starches (Mook Starches). Corn, rice, wheat starches (Non-Mook Starches) are not used due to their weak gelation power. In order to know the effects of properties of starch on gelation, some physicochemical properties, molecular structure, and starch lipid of these six starches were investigated and compared with gel hardness. Both amylose content and gel hardness of starches were in order of mungbean, acorn, buckwheat, wheat, corn, and rice and these two parameters showed a very good correlation (r=0.95). The amyloses of Mook Starches had larger molecular size (${\overline}D.P._{n}=1,080{\sim}1,580\;vs\;670{\sim}1,120$ for Mook Starches and Non-Mook Starches, respectively), more average number of chain ($2.9{\sim}5.4\;vs\;1.7{\sim}2.5$), and shorter average chain length ($290{\sim}390\;vs\;390{\sim}450$) than those of Non-Mook Starches. Also, Mook Starches had longer average chain length ($22.2{\sim}22.6\;vs\;18.9{\sim}21.3$) of amylopectin and less starch lipid content ($0.12{\sim}0.49\;vs\;0.68{\sim}1.26%$) than Non-Mook Starches. These properties had good correlations with gel hardness (r=0.76-0.84). Consequently, the gelation power of Mook Starches was thought to be derived from their high amylose content and other properties of starches.

전분의 어떤 성질이 묵 형성을 영향을 주는가를 알기위해 도토리, 메밀, 녹두 전분(묵전분)과 옥수수, 쌀, 밀 전분(비묵전분)의 이화학적, 분자구조적 성질과 전분지방질의 함량을 조사하여 겔 강도와 비교하였다. 전분의 아밀로오스 함량은 녹두, 도토리, 메밀, 밀, 옥수수, 쌀 순이었으며 겔 강도 역시 같은 순서로 나타나 이들 사이에서 가장 좋은 상관관계를 보였다(r=0.95). 묵전분의 아밀로오스의 특성을 보면 비묵전분보다 분자크기가 켰고(${\overline}D.P._{n}=1,800{\sim}1,580\;vs\;670{\sim}1,120$), 평균 가지수가 많았으나(${\overline}N.C.=2.9{\sim}5.4\;vs\;1.7{\sim}2.5$), 평균 가지 길이는 작았다(${\overline}C.L.=290{\sim}390\;vs\;390{\sim}450$). 묵전분의 아필로펙틴의 ${\overline}C.L.$은 비묵전분보다 컸으며 ($22.2{\sim}22.6\;vs\;18.9{\sim}21.3$), 전분지방질의 함량은 비묵전분보다 더 작았다($0.12{\sim}0.49\;vs\;0.68{\sim}1.26%$), 이들 분획물의 성질과 지방질함량은 겔 강도와 좋은 상관관계($r=0.76{\sim}0.84$)를 보였다. 따라서, 묵전분의 겔 형성능력은 아밀로오스 함량과 전분의 여러 특성이 종합적으로 작용해 나타내는 것으로 보인다.