Study on durian seed as a new substrate for angkak production

A study was carried out to examine the potential of durian seed as a new substrate of Monascus sp. for angkak production. The durian seeds were analyzed for their proximate composition and starch content. After pretreatment, different volumes of distilled water were added to sterile small size cut of durian seeds to set the initial moisture content of 58%, 59%, 60%, 61% and 62%, inoculated with Monascus sp. KJR2 culture and were incubated for 14 days at room temperature (30°C). The fermented-durian seeds were dried and analyzed for the yellow, orange and red pigments. The durian seeds contain 54.90% moisture, 1.58% ash, 3.40% protein, 1.32% fat and 18.92% starch. The results indicated that initial moisture content significantly affect the pigments content. Water-soluble yellow, orange and red pigments contents were in the ranges of 6.01 to 11.17 AU/g, 3.82 to 8.52 AU/g and 3.57 to 8.11 AU/g, respectively. Ethanol-soluble yellow, orange and red pigments contents were in the ranges of 1.09 to 3.86 AU/g, 0.51 to 2.51 AU/g and 0.72 to 3.73 AU/g, respectively. The substrate with initial moisture content of 60% was the most suitable substrate for angkak production, yielding Monacolin K of 50 mg/kg. The durian seed has good potentiality to be used as a new substrate for angkak production and more researches are needed to increase the monacolin K content and to evaluate the durian seed angkak functionalities and safety.