흑미가루를 첨가한 쌀 식빵의 품질 특성

Quality Characteristics of Rice Bread Substituted with Black Rice Flour

일반 쌀가루에 활성 글루텐, gum 및 유화제를 첨가하여 쌀 빵을 제조시에 흑미가루의 부분적인 대체(10~30%)가 쌀 식빵의 품질 특성에 미치는 영향을 조사하였다. 쌀 식빵의 부피는 일반 쌀가루로만 제조한 100% 쌀가루 식빵에 비해 흑미가루의 첨가 수준이 증가함에 따라 점차 감소하였다. 흑미가루를 첨가한 쌀 식빵의 내부색은 흑미의 어두운 색상에 의해 L값이 현저히 감소하여 어두워졌으며, 적색도는 증가하고, 황색도는 약간 감소하였다. 흑미가루 첨가 쌀 식빵의 저장 중 텍스쳐에서 대조구 쌀 식빵과 비교하여 흑미가루 10~20% 첨가 쌀 식빵은 3일간 저장 기간 중에 식빵의 경도에 크게 차이를 보이지 않았으나, 흑미가루 30% 첨가 쌀 식빵에서는 경도가 현저히 높게 증가하였다. 흑미가루 첨가 쌀 식빵의 DPPH radical 소거능은 흑미 첨가 비율이 증가함에 따라 증가하여 흑미 첨가 쌀 식빵의 항산화 활성은 높아지는 것으로 확인되었다.

Yeast-leavened rice bread with added vital wheat gluten was formulated by substituting normal rice flour with 0~30% black rice flour, and the effects of black rice flour substitution on rice bread quality were investigated. Black rice flour contained more protein, lipid, and ash contents than normal rice flour. Increasing levels of black rice flour substitution decreased the specific loaf volume of rice bread. Black rice flour decreased lightness and yellowness, and imparted a reddish color in the bread crumbs. Only a slight difference in crumb firmness was observed between control rice bread (100% normal rice flour) and rice bread containing up to 20% black rice flour. However, crumb firmness of rice bread containing 30% black rice flour was considerably higher than that of the control rice bread and increased rapidly at 2~3 days during a 3-day storage period at $25^{\circ}C$. Antioxidant activity of rice breads was estimated by determining electron-donating ability (EDA) to DPPH radical. The electron-donating ability slightly increased with increasing levels of black rice flour in rice bread.