| Recently, with the improvement of our life standard and foodstuff industries, our seasoning yield has been increased a lot. And the production quality also has been developed in high rate. Various kinds of seasoning have been emerged endlessly. At the same time, variety kinds of seasoning such as new types of convenience seasoning, pure natural seasoning, complex seasoning and nutritional health protection seasoning emerge as times require. Millet is enriching of nutrition, has high value of edible and especial function for health care. It not only has abundant of nutrimental substances just like protein, fat and carbohydrate, it is also a kind of food which can adjust the physiology of our bodies and an indispensability part of our daily life. On the process of producing koji, Aspergillus oryzae is possessed of absolute superiority; its capability has direct affect on quality of sauce koji and the quality of soy sauce. When using the Aspergillus oryzae to ferment and brewing millet paste, it can improve the millet's edible quality and the machining depth of foodstuff, accordingly product higher nutrition value and economic value.In this study, spontaneous fermentation was adopted. And traditional technique was used to produce millet paste, and Aspergillus oryzae was separated by Martin culture medium after the preparation of fungi liquid and proper dilution. In natural conditions, various bacteria usually jumble together, so in order to gain pure Aspergillus oryzae, it should be purified at least three times. After separating and gaining Aspergillus oryzae strain, temporarily slide checkup was made to identify it. According to the result of the temporarily slide checkup using high microscope, the peduncle length of conidiophores is 2 mm; the head of conidiophores is emanation form and nearly round peak theca ,and the small peduncles are almost monolayer, flat and round. Observing the colony producing on the Char culture medium or the pictures taken by microscope using the method of the slide glass culture, it is confirmed that the strain separated is Aspergillus oryzae and Aspergillus oryzae flora.After separating and gaining Aspergillus oryzae strain, single colony was selected to measure the producing capability, including the activity of proteinase and the number of spore. And after pure strain separation, the numbers of strains were very large. Filtration had to be done with these strains. There were two steps of filtration. It can be filtered many times until obtain the choiceness strains. Former filtration uses the double deck casein culture. Along with the single colony growing larger and larger, it will be appear translucent circle around the colony. According to the size of the translucent circle on the culture, the proteinase activity can be confirmed. After choosing the more excellent strain by prime filtration, filtration can be done again, and then its proteinase activity and spore number of the strains were determined. The strains chosen by prime filter were grown on the inclined plane. When growing on the culture, their numbers of spores were determined at 48h and 72h. The tube incline was prepared to furgi liguid and diluted to proper conlentration to take count by blood corpuscle counter. After the inclvne culturing, then proteinase activity was measured. Because of the higher stability of forint reagent on the condition of alkalescence, it can be deoxidized by hydroxybenzene compounds and blue reaction. The depth of color can make sure the activity of proteinase. At last, three kinds of strains : S1,S2,S3 were chosen. Those were chosen by many times of filtration and mensuration. After 48 hours and 72 hours, one of the strains of S1 has 2.76×106 spores/ml and 1.15×107 spores/ml respectirely, with proteinase actirity of 3314.55 U/g ; and the secondo strain S2 has 1.30×107 spores/ml and 1.91×107 spores/ml,with proteinase,activity of 1491.29 U/g ; and the fhird strain S3 has 1.01×106 spores/ml and 3.25×107 spores/ml with proteinase activity of 3013.11 U/g.The frequency of spontaneity mutation of the choiceness strain which obtained by nature select is very low, and has less spores with low proteinase activity, so it can not satisfy the requirement of breeding industry. So it have to take mutate breeding to select the prime strain. The strains of S1,S2,S3 are taken as prime furgi. After using physic revulsant ultraviolet radiation to deal with the strainsa, the best dosage is confirmed by taking count of living fungi. When irradiated by ultraviolet radiation uprighthy, mass of cells were dead, but the units still alive had great improvement in DNA base aberrance frequency. The sporesnumber and proteinase activity were measured after duturing, and compared to prime ones to eliminate negative mutation. Thus excellent capability positive mutation fungi are obtained.The measurement results are as follows. The numbers of spores have biy improvement. The strain Y34 mutated from S3 has 20.04×106 spores/ml, which is 19 times higher than the prime one. And the proteirase activities are all improved except S3.The proteinase activity of Y26 mutated from S2 is 8593.51 U/g, and it is 5 times higher than prime one. Finally, the excellent mycelium of Y26 and Y34 are selected and saved to study the optimal condition of fermentation techniques. When using the Aspergillus oryzaes respectively separated from rice paste and millet paste to brew millet paste, the millet paste of two kinds is different in sense. It is confirmed that the paste will be smells good when using the Aspergillus oryzae separated from millet paste to brew millet paste only.
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