To reproduce the brewing process of Hongkuk-ju and to identify the functional properties of it, Hongkuk-ju was brewed using different additions of Hongkuk (100%, 90%, 70%, 50%) and Nuruk (0%, 10%, 30%, 50%). The quality elements, including pH, total acidity, reducing sugar content, alcohol content and pigments (yellow, red, monacolin K and citrinin), were measured. The pH values of Hongkuk-ju showed a slight difference (pH 4.08～4.58) right after the 1st stage mash; further, the pH on all groups (H1, H2, H3 and H4) in the terminal of the 2nd stage mash (9 days in fermentation) were similar, ranging approximately at pH 3.70. The total acidity change did not show a difference directly the 1st stage mash (nearby 0.2 %); however, it began to show a slight difference at the terminal of the 2nd stage mash between the range of 0.69～0.76%. The residual reducing sugar of the content was decreased with the increased Nuruk content. The alcohol concentrations of the treatment brew with Nuruk ranging from 12.3% to 13.7% were higher than Hongkuk on its own. The yellow and red pigment contents of Hongkuk-ju ranged from 7.2～8.8 O.D. units (yellow pigment) and from 4.4～5.1 O.D. units (red pigment). The production of monacolin K and citrinin was the highest (9.48 ㎎/㎏ and 10.14 ㎎/㎏) when the treatment solely brewed Hongkuk. The concentration of Nuruk and the preparation of the seed mash from it were critical factors compared to the treatment of rice in brewing Hongkuk-ju

In order to produce Hongkuk-ju, the production and characterization of Hongkuk (Monascus red koji) by Monascus anka KCTC 6121 were investigated. The optimum cultural conditions for the production of enzyme (α-amylase and glucoamylase) and pigment (yellow and red) from this strain on solid culture (steamed rice) were examined. The results showed that the production of α-amylase and glucoamylase reached the highest for 9 days and 8 days, respectively. Since then, the productions decreased slightly. The production of yellow and red pigments reached the highest for 8 days, decreasing slightly soon after. The optimal content of the initial moisture equally presented 30% in the enzyme and pigment production. After that, the enzyme production decreased slowly, whereas pigment production decreased sharply. The optimal temperature of the culture also showed 30℃ in the production of enzyme and pigment. It was found that the initial inoculum size in enzyme and pigment production was 10% and 20%, respectively. Under these optimal conditions, the production of monacolin K and citrinin was 74.35 ㎎/㎏ and 5 ㎎/㎏ for 12 days, respectively.

Monascus anka KFCC 4478의 적색소 생산력을 증가시키기 위하여 발효조 배양조건을 검토한 후, 탄소원을 연속적 또는 간헐적으로 공급하는 유기배양을 하였다. 5l 용량의 발효조를 이용하여 배양시 교반속도 200rpm, 통기량 1vvm 및 종균 접종량 10%(v/v)일 때 색소 생성량이 최대였다. 또한 벽면에 부착된 균사체를 재접종함으로써 색소 생성력이 향상되었다. Intermittent feeding fed-batch culture에 의하여 배양 9일만에 30g/l의 건조균체와 350(A_495)의 색소가 생성되었으며, continuous feeding fed-batch culture에 의하여 22g/l의 건조균체와 190(A_495)의 색소가 얻어졌다. 따라서 본 균주에 의하여 적색소를 생산코자 할 경우는 회분배양보다 유기배양이 더 우수한 것으로 나타났다.