By: Jenie BSL, Ridawati, Rahayu WP
Department of Food Science and Technology, Bogor Agricultural University
M. purpureus in tapioca liquid waste medium consisted of 2 % tapioca and 0.15 % ammonium nitrate produced the highest red pigment intensity (500 nm) either for extracellular or intracellular pigments. The intensity of the intracellular pigment produced was higher than the extracellular pigment. Addition of tapioca solid waste into the medium increased the intensity of the intracellular pigment (11.79) compare to the addition of rice flour (8.53). Utilization of 2 % tofu solid waste as nitrogen source resulted in lower intracellular pigment intensity (8.24) than ammonium nitrate (12.08). The optimum pigment production was achieved after 12 days fermentation. The red pigment was first detected in the medium on the third day of fermentation when the dried cell mass reached maximum. The intensity of the pigment continued to rise during prolonged fermentation while the dried cell mass began to decrease. The starch content decreased during fermentation and the sugar content was first increase for 3 days and then decrease. The solubility of red pigment in water was affected by the carbon and nitrogen sources used in the medium. Tapioca solid waste and ammonium nitrate as well as water temperature at 80oC increased the pigment solubility.
Keywords: angkak, Monascus purpureus, tapioca, tofu, waste
Dimuat di Buletin Teknologi dan Industri, Volume 5 No. 3, 1994, ISSN 0216-2318