Abstract

The effect of oxidants, gluten and gums on breadmaking quality of wheat-purple sweet potato(Ipomoea batatas) composite flour were studied. Alveograph tests of doughs showed that all additives increased the P, L and W values. Of these additives, L-Ascorbic acid, gluten, carboxy methyl cellulose have a significant effect on alveogram indexes. SEM showed that the dough added with additives changed some what in appearance when compared with the control. When oxidants was added, the doughs discontinuous gluten film were observed. No significant differences ,were evident in bread crumb color among the additives. And textural characteristics of bread crumb were influened by adding additives. Breads containing additives showed an increase in max weight, strength and hardness and a decrease in springness and cohesiveness. Average enthalpy values for all bread crumb after 7days increased with storage time. However, addition of additives decrease the rate of staling slightly more than that of the control. Addition of L-Ascorbic acid, L-Cystine, carboxy methyl cellulose and hydroxy propyl methyl cellulose increased the loaf volume significantly, and with except potassium bromate bread scores were acceptable.

밀가루(80%)와 자색고구마가루(20%)를 이용한 복합분으로 고구마빵을 제조하기 위하여 L-ascorbic acid, potassium bromate, gluten, carboxy methyl cellulose 및 hydroxy propyl methyl cellulose 등의 물성개량제를 첨가하여 고구마빵의 제빵성을 비교.검토하였다. Alveograph에 의한 반죽특성은 물성개량제를 첨가함에 따라 P, L, W값이 증가하였으며, 특히 L-ascorbic acid, gluten, carboxy methyl cellulose 등의 영향이 컸다. 반죽의 표면구조는 산화제를 첨가한 경우 gluten의 얇은 막이 거의 관찰되지 않았고, gluten, carboxy methyl cellulose, hydroxy propyl methyl cellulose를 참가한 경우 전분입자의 형태는 비교적 선명하나 큰 전분입자를 중심으로 얇은 막으로 둘러싸여 있었다. 빵 내부색의 총체적인 차이를 구별할 수 있는 ΔE값은 첨가제에 의한 영향은 없었으며, 빵 내부의 물성은 최대하중치, 강도, 경도 특성치가 사용첨가제에 의해 감소하였으며, 탄성, 응집성의 특성치는 증가하였다. 빵 내부의 노화특성은 7일 냉장저장 결과 엔탈피($\Delta$H)값이 증가하였으나 각 첨가제 모두 노화지연 효과가 있었다. 빵의 부피도 첨가제를 사용함으로써 증가하였으며 특히 L-ascorbic acid, L-cystine, carboxy methyl cellulose 및 hydroxy propyl methyl cellulose 등의 효과가 좋았고, 관능검사결과 potassium bromate를 제외하고 전반적으로 제빵의 품질이 양호하였다.

Keywords

• purple sweet potato;
• additive;
• breadmaking