Kōji

Question 1

What is kōji?

Answer 1

Steamed rice (or barley or other types of grain) inoculated with kōji-kin fungus.

Question 2

What does kōji do?

Answer 2

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.

Question 3

what are the three categories of kōji-kin?

Answer 3

1. Ki-kōjo-kin -yellow
2. Shiro-kōji-kin - white
3. Kuro-kōji-kin - black

Question 4

Which type of kōji-kin is used primarily for sake?

Answer 4

Ki-kōji-kin

Question 5

What are the two types of tane-kōji?

Answer 5

Granulated and powdered

Question 6

Granulated tane-kōji is most frequently used for what type of sake?

Answer 6

Ginjo

Question 7

How long does it take to make koji?

Answer 7

40-48 hours.

Question 8

Describe so-haze

Answer 8

The koji spore covers the entire rice grain sending many hyphae growing into the kernel.

Question 9

Describe tsuki-haze

Answer 9

The koji spores grow in a lightly spotted pattern over the rice grain with fewer hyphae growing into the kernel.

Question 10

Which style dissolves the rice well and promotes strong fermentation.

So-haze or tsuki-haze?

Answer 10

So-haze

Question 11

Tsuki-haze results in sake that is fuller-bodied.

T or F

Answer 11

False

Question 12

During koji making, what is created besides glucose?

Answer 12

vitamins, amino acids, peptides, malic acid, succinic acid.

Question 13

List the seven steps of the Koji making process.

Answer 13

1. Bringing in
2. Spread seed
3. Re-breaking up
4. Mounding
5. Middle Work
6. Final Work
7. Sending Out

Question 14

Describe Futa-koji

Answer 14

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.

Question 15

Describe Hako-Koji

Answer 15

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.

Question 16

Describe Toko-koji

Answer 16

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.

Question 17

How long does koji-kin normally take to form?

1. Six hours
2. One day
3. Two to three days
4. One week

Answer 17

3. Two to three days

Question 18

What are the ideal conditions for koji mould growth?

Answer 18

High humidity and temperatures between 33C and 38C (92F-100F).

Question 19

What is the primary role of koji?

Answer 19

Creates enzymes which break down the starch in the rice into sugars.

Question 20

How much of the total amount of rice used to make sake (on average) is koji?

Answer 20

20-25%

Question 21

How many times is koji used in sake production?

Answer 21

4 times:

To make the moto, and in each addition in sandan jikomi

Question 22

What is the legal minimum amount of koji required to be called seishu?

Answer 22

15%

Question 23

How many strains of ki-koji kin are there?

Answer 23

Thousands; however more important than the specific strain is the skill of the toji and the method used to employ the koji-kin

Question 24

High levels of mould growth covering the outside of the rice grains result in sakes with:

Answer 24

more flavour, intensity, acidity, and umami

Question 25

Low levels of mould growth, mainly in the middle of the rice grains creates sakes with:

Answer 25

lighter flavour, less acidity and umami

Question 26

Tsuki-haze kōji is typically used in sakes with high levels of acidity and umami.

T or F

Answer 26

False