Colorant Extracting and Its Storage Stability from Red bean and Black bean Seed Coat

팥 종피에서의 색소 추출과 저장 안정성

Extraction efficiency of colorants from red bean and black bean seed coat and its storage stability were examined according to the various extracting and storage conditions in this study. The obtained results were as follows ; The absorbance values of extracted colorants were increased with increasing extract time and temperature. pH 4 extracting was most efficient among the various pH conditions. The absorbance values of extracted colorant from red bean were increased with increasing extract time and temperature, when the extraction process was kept at $30^{\circ}C$ and $50^{\circ}C$, but it were decreased with increasing extract time at $70^{\circ}C$. In the case of black bean, it were also increased with increasing extract time and temperature. pH 5 extract was most efficient among the various pH conditions. In juice extractor system from red bean, the pH 5 of the pre-treatment was more efficient than the distilled water of pre-treatment. In black beans of the short-term pre-treatment with distilled water, the colorant was extracted better than at pH 5, but above 4 hours pre-treatment was decrease in pH 5. The Methionine added as a stabilizer gave the more effect to the stability of colorant from red bean the more Methionine addition. In the case of black bean 10mmol addition of methionine was more efficient than 20mmol.

본 연구에서는 붉은팥과 검정팥 종피에 함유된 천연색소에 대한 연구의 일환으로, 추출방법에 따른 색소 추출 효율과 저장안정제 첨가에 따른 저장 안정성과 특성을 검토하여 다음과 같은 결과를 얻었다. 1. 붉은팥 종피의 용액 추출 시 $50^{\circ}C$까지는 온도가 높을수록, 시간이 경과될수록 색소 추출 효율이 높게 나타났으나, $70^{\circ}C$에서는 시간이 경과될수록 색소 추출효율이 감소하는 경향을 보이며 pH 조건에서는 pH 5가 가장 효율적이었다. 2. 검정팥 종피의 용액 추출 시 온도가 높을수록, 시간이 경과될수록 색소 추출 효율이 높게 나타났으며, pH 조건에서는 pH 5가 가장 효율적이었다. 3. 착액 추출 시, 붉은팥의 경우 pH 5의 전처리가 증류수보다 색소 추출량이 많았으며, 검정팥의 경우 단시간 전처리에서는 증류수가 pH 5에서 보다 색소 추출량이 많았지만, 4시간 이상의 전처리에서는 오히려 pH 5에서 많게 나타났다. 4. 저장 안정제로 Methionine을 첨가한 결과에서는 붉은팥 종피의 경우에는 첨가량이 많을수록, 검정팥 종피의 경우에는 10mmol첨가가 20mmol 첨가보다 안정 효과가 큰 것으로 나타났다.