Aspergillus Oryzae (Koji)

[Owly055]

Information on the processes involved with Aspergillus oryzae growth on grain seems to be extremely sparse, except specific processes involved in making various products such as Saki, Rice Wine, Miso, etc.
Aspergillus oryzae is of interest as it produces amylase as it grows on warm moist grain. It is the process that enables rice to be turned into saki or rice wine, miso, and other products. but those methods are fairly well defined, traditional and specific to the products being made.
My interest is in using this fungus with barley in beer brewing, and also with other starch sources as well.

My questions are about the conversion process. To what extent is starch conversion accomplished if any, during the 48 hours or so in which the Aspergillus oryzae is growing on the grain? If none, or little, it would seem to be necessary to dry and crush, basically leaving you at the same point as you would be doing malting after sprouting was finished. If conversion is accomplished during this period, then the process would be different presumably. For example kilning for color and flavor development, followed by crushing, and a pseudo mash.

My thinking is to crack the barley through my mill first, steam it, and innoculate it. It would be a course "crush" basically with intent of exposing the starches to the fungus and it's amylase.

It all seems like terra incognita, and a great area to focus some serious experimenting, as there seems to be virtually no relevant documentation.

This fungus seems like a perfect match for something like sweet potatoes also. I envision grating them and steaming them, or dry roasting followed by steaming, followed by innoculation.

There are many non-maltable starch sources, and Aspergillus oryzae seems like a logical tool for using them. I already use AG300 frequently, which is a derivative of this fungus.

...................... Anybody do any seious real world experiments with this stuff beyond simply making saki and rice wine by rote?

H.W.

 

[Brownalemikie]

Say what!!!!

 

[SplitHops]

Information on the processes involved with Aspergillus oryzae growth on grain seems to be extremely sparse, except specific processes involved in making various products such as Saki, Rice Wine, Miso, etc.
Aspergillus oryzae is of interest as it produces amylase as it grows on warm moist grain. It is the process that enables rice to be turned into saki or rice wine, miso, and other products. but those methods are fairly well defined, traditional and specific to the products being made.
My interest is in using this fungus with barley in beer brewing, and also with other starch sources as well.

My questions are about the conversion process. To what extent is starch conversion accomplished if any, during the 48 hours or so in which the Aspergillus oryzae is growing on the grain? If none, or little, it would seem to be necessary to dry and crush, basically leaving you at the same point as you would be doing malting after sprouting was finished. If conversion is accomplished during this period, then the process would be different presumably. For example kilning for color and flavor development, followed by crushing, and a pseudo mash.

My thinking is to crack the barley through my mill first, steam it, and innoculate it. It would be a course "crush" basically with intent of exposing the starches to the fungus and it's amylase.

It all seems like terra incognita, and a great area to focus some serious experimenting, as there seems to be virtually no relevant documentation.

This fungus seems like a perfect match for something like sweet potatoes also. I envision grating them and steaming them, or dry roasting followed by steaming, followed by innoculation.

There are many non-maltable starch sources, and Aspergillus oryzae seems like a logical tool for using them. I already use AG300 frequently, which is a derivative of this fungus.

...................... Anybody do any seious real world experiments with this stuff beyond simply making saki and rice wine by rote?

H.W.

It would seem to me, and I am no scientist for sure, but as this little critter is a fungus it will need a food source or host, that being your endosperm of the grain which you state will be in fact barley cracked and steamed. I am not certain but the endo sperm needs prolonged heat and moisture to convert it from starch to sugar or in this case an edible food source for your bug, just steaming it may not convert it as you would like it to.

I will be curious to see what you do with this, as I love to experiment with this stuff as well.

 

[crnigjuro]

I remember reading about koji beer made by Nordic food lab...here are some links:

http://nordicfoodlab.org/blog/2013/12/roasting-koji

http://nordicfoodlab.org/blog/2013/10/vinegar-science-pt-4?rq=koji

I am also interested in making koji beer, the only problem being how exactly to get koji culture here in EU....

The more I read about koji, the more I want to experiment with it and various non-barley grains. If it manages to make even rice smell and taste like fruit....

 

[5mooth0perator]

You could try reading the instructions on the package of Koji. I read the instructions on the the Nuruk at my local Korean market, seems like they just boiled the rice and inoculated. That's to make the Korean rice drink. I think they ferment the mold and the yeast at the same time. I recall reading that some sake is actually barley based rather than rice. Also, I gather that there are different varieties and flavors of Koji, because it is the same basic process for soy sauce, miso, sake etc.

 

[5mooth0perator]

This is a nice tutorial on makgeolli.

https://www.maangchi.com/recipe/makgeolli