Applied Fungus Technology

Outline of Koji and Yeast stater producing process

HOMEOutline of Koji and Yeast stater producing process

1. The history of Moyashi
Koji starter (Tane-Koji) which is the pillar of the Japanese fermented foods such as Sake, Miso, soy sauce and Shochu is called Moyashi. Our products are called 'AKITA KONNO MOYASHI' or 'KONNO MOYASHI'. 'Moyashi' means 'sprout', because of that, Koji starter (Tane-Koji) became to be called 'Moyashi' in a common belief.
Tane-Koji business was established in our country a long time ago. In fact, Tane-Koji guild received an exclusive permission from the Shogunate in the Muromachi period during the 13th to 15th centuries.
Tane-Koji is a starter culture of Asp. oryzae for making Koji. Koji fungi are cultured on steamed rice at polishing ratio 96% with trace of ash at 34 to 36℃ for one week during the production of Tane-Koji.
The ash to mix in Tane-Koji making is made by burning leaves such as camellia, zelkove or oak in the roster. Ash is rich in mimeral nutrition sources such as potassium, magnesium and phosphate.
The effects by ash are to increase spore yield and survival rate, and to inhibit various contaminants. The starter of Tane-Koji in these day was prepared by drying aged Koji and ash. Making Tane-Koji at that time was very primitive, but pure culture using flask, which we adouped first, was epochmaking. Therefore, Konno Moyashi made rapid progress.
2. Tane-Koji
(Asp. oryzae)
White Koji
(Color mutant of Asp. oryzae)
Black Koji
(Asp. awamorii)

There are some differences in making between Tane-Koji and Koji.
1) The main parpose of Koji making is the producing enzyme. However, that of Tane-Koji is the producing spores for Koji making.
2) For Koji making, polished rice or barley is uesd and it takes about two days. But for Tane-Koji making, nutritious rice with high polishing rate (brown rice) is used and it takes about one week.
3) Tane-Koji is normally dried for quarity keeping.
4) In Tane-Koji making, about one parcent of ash is added to steamed and cooled rice for good growing of Koji fungi and good sporing, and improving preservation.
The best ash is camellia ash, but sometimes Tane-Koji is made without ash.

Several kinds of Tane-Koji have been developed from different strain of Aspergillus that have been handed down as heirlooms by every producers and some of them are obtained by natural or artificial mutation. Since olden times Tane-Koji has been distributed to all brewer's by Tane-Koji producers, and the strains used for Tane-Koji has eventually formed a unique group of fungi, different from the wild types, as a result of the long history of development.

Outline of producing process of Koji starter
Outline of producing process of yeast and lactic acid bacteria starter
Sake and Shochu yeast
Koji extract, natural culture medium, is used for Sake and Shochu yeasts as culture medium. To make Koji extract, First, rice Koji is saccharified and then filtered after no showing iodo-starch reaction. Then boiled up for taking cloud off. This is filtrated again and controled its sugar content.

Sake and Shochu
yeast in agar
  Seed culture in flask   Main culture in flask   Product
Beer yeast
The concentrated malt extract is uesd for culture medium of beer yeast. The concentrated malt extract is made by saccharifing dried malts, boiling, filtrating, concentrating and controling sugar content.
Beer yeast in
agar slant
  Culture in flask   Incubation in Jar-fermenter   Product
Miso and Soy sauce yeast
The mixture of Ki-Joyu (soy sauce with no additives such as amino acids and antiseptic for foods), glucose and salt is uesd as culture medium.
yeast for Miso in
agar slant
  Culture in flask   Main culture in flask   Product

Lactic acid bacteria for Miso
Lactic acid
bacteria for Miso
  Culture in flask   Incubation in Jar-fermenter   Product