Kōji Flashcards
What is kōji?
Steamed rice (or barley or other types of grain) inoculated with kōji-kin fungus.
What does kōji do?
It creates enzymes that convert rice starch into fermentable sugar. Kōji also produces other enzymes that break down protein and produces amino acids and peptides.
what are the three categories of kōji-kin?
- Ki-kōjo-kin -yellow
- Shiro-kōji-kin - white
- Kuro-kōji-kin - black
Which type of kōji-kin is used primarily for sake?
Ki-kōji-kin
What are the two types of tane-kōji?
Granulated and powdered
Granulated tane-kōji is most frequently used for what type of sake?
Ginjo
How long does it take to make koji?
40-48 hours.
Describe so-haze
The koji spore covers the entire rice grain sending many hyphae growing into the kernel.
Describe tsuki-haze
The koji spores grow in a lightly spotted pattern over the rice grain with fewer hyphae growing into the kernel.
Which style dissolves the rice well and promotes strong fermentation.
So-haze or tsuki-haze?
So-haze
Tsuki-haze results in sake that is fuller-bodied.
T or F
False
During koji making, what is created besides glucose?
vitamins, amino acids, peptides, malic acid, succinic acid.
List the seven steps of the Koji making process.
- Bringing in
- Spread seed
- Re-breaking up
- Mounding
- Middle Work
- Final Work
- Sending Out
Describe Futa-koji
The koji-innoculated rice is moved to futa, smaller containes resembling lids or trays. The separating allows the humidity and temperatures of the rice to become more even, The brewers can shift the locations and layers everty 3 hours or so. This method handles 1.5 kg to 2.5 kg of rice. Used for higher grade, expensive sake.
Describe Hako-Koji
Box koji - This method is commonly used for a wider range of sake. It is a simplified version of Futa-Koji. The brewer puts the rice into large boxes, futa, split with a divider that can slide from side to side to control the release of temperature. Handles 15 kg to 40 kg of rice.
Describe Toko-koji
Steamed rice is placed on a special table, the toko. This method allows for a large volume of rice but does not allow for precise manipulation. Primarily used for futsushu.
How long does koji-kin normally take to form?
- Six hours
- One day
- Two to three days
- One week
- Two to three days
What are the ideal conditions for koji mould growth?
High humidity and temperatures between 33C and 38C (92F-100F).
What is the primary role of koji?
Creates enzymes which break down the starch in the rice into sugars.
How much of the total amount of rice used to make sake (on average) is koji?
20-25%
How many times is koji used in sake production?
4 times:
To make the moto, and in each addition in sandan jikomi
What is the legal minimum amount of koji required to be called seishu?
15%
How many strains of ki-koji kin are there?
Thousands; however more important than the specific strain is the skill of the toji and the method used to employ the koji-kin
High levels of mould growth covering the outside of the rice grains result in sakes with:
more flavour, intensity, acidity, and umami
Low levels of mould growth, mainly in the middle of the rice grains creates sakes with:
lighter flavour, less acidity and umami
Tsuki-haze kōji is typically used in sakes with high levels of acidity and umami.
T or F
False
