Determine of appropriate cultural growth conditions for production of starter culture from rhizopus oryzae went and prinsen geerlings

Abstract

A starter culture is a source of pure microorganisms used to produce traditional fermented products of high quality, stability, and safety. The starter culture contains spores and hydrolysis enzymes produced during mold growth. This work was conducted to determine the appropriate cultural growth conditions for Rhizopus oryzae and biosynthesis of the protease enzymes, and then set up a manufacturing process for the starter culture which can be used to produce the fermented product from tofu. The microorganism was most successfully cultured with corn or soybean meal and rice flour in a 60/40 ratio. The flour mixture was autoclaved, spread to a height of 2 cm followed by the addition of the spore suspension with a density of 2.107 bt/ml at a rate of 2 ml of spores/100 g culture medium. Incubation lasted 54 h with a turning at 24h. After incubation, spores and enzymes were preserved through freeze drying (-45°C) or oven drying (40°C) until a moisture of 10% was reached.