C2 - An Overview of Sake Production - completed Flashcards
What is the main raw material for making sake?
Steamed white rice
What is the function of water and kōji in making sake?
Rice is a solid with a starchy core that needs water and kōji to convert the solid starch into a sugary fermentable liquid.
What else is need aside from enzymes to convert the sugars into alcohol?
yeast
Briefly describe the growing cycle of rice by season
- planted in spring
- grown in summer
- harvest in autumn
Rice is an ___ ___ crop
edible cereal
How long can rice be stored once it’s harvested?
a few months
What kind of land can the rice farmed?
- flooded rice-paddies in Japan
- dry fields, usually in the USA.
What are the two main subspecies of Asia rice?
1 - long grained (Indica)
2 - short grained (Japonica)
What are the two types of rice subdivided under Indica and Japonica?
1 - sticky (glutinous)
2 - non-sticky (non-glutinous)
Which type/species of rice is only be used for brewing sake?
the non-sticky short grained rice.
List a few of the characteristics of the non-sticky short grained rice
- easy to farm
- high yield
- grown in Japan and elsewhere
- as table rice for eating
- also suitable for making sake
What are the challenges of growing sake-specific rice?
harder to farm and lower yields
Why the sake brewers like to use the sake-specific rice?
it’s easier to separate cleanly the starch from the proteins and other undesirable parts of the rice grain
Which 3 reasons make the sake-specific rice easier to separate the starch from the proteins of the rice grains?
- they contain less protein then table rice
- most of the starch granules lie in a well-defined almost pure starch core
- they are larger-grained, therefore less likely to crack when polished.
What is the first step to process the rice before being used in sake production?
polishing
What is the purpose of polishing the rice?
to remove the:
- proteins
- lipids
- vitamins and
- minerals
in the outter part of the rice grain.
Leaving just the starchy core
What is the polishing ratio referred to?
The amount of the remaining rice after polishing.
What is the difference between table rice and sake-specific rice in terms of polishing
table rice are less highly polished than rice used in sake brewing
Why the polishing ratio will affect the final style and category of the sake?
Polishing determined the amount of the rice is polished and the amount of proteins, lipids, viatmins and minerals that remain.
What is the second step after polishing?
- the rice grains need to be cleaned to remove any remaining fine rice powder
What is the purpose of cleaning and removing the fine rice powder?
- the powder is made up of tiny fragments of the bits of rice was trying to remove, they would make the sake less pure, more rough-textured and acidic.
How the fine rice powder is removed in the cleaning process?
by washing, either in:
- small container
- large vats
- or a continuous rice polishing machine
Characteristics of sake made from highly polished rice:
- have purer, fruitier flavours
- lighter in body
- lower acidity and umami
Characteristics of sake made from less highly polished (coarsely polished) rice:
- have more savory
- less fruity flavours
- more body
- more acidity
- more umami
- price tend to be lower
What are the 3rd and 4th steps after polishing?
- soaking and steaming rice
What is the purpose of soaking?
to alter the amount and distribution of water within the rice grain
What is the duration of soaking for the purest and most delicate sakes?
- a few minutes to be done precisely.
Traditionally, how much rice are steamed in batches
approximately one tonne, last about an hour
What are the 3 purposes of combining the soaking and steaming process?
1 - raising the moisture level within the grain
2 - changing the starch
3 - disinfection of the rice
Describe how soaking and steaming raise the moisture level within the grain
- soaking helps the rice absorbs enough water to be soft and moist inside.
- steaming (rather than boiling) means the outside of the rice remains firm.
What are the benefits of raising the moisture level with the grain?
- perfect the distribution of moisture for producing the best kōji
- make sure the rice breaks up during fermentation at the right speed
Describe how soaking and steaming change the starch
- The heat changes the structure of the starch, so that the kōji enzymes can break into fermentable sugars
- Without heat, the starch remains in a form that the kōji enzymes cannot break it apart.
What is the benefit of using steaming to disinfect the rice?
- steaming kills the undesirable microbes that may be on the rice which may contaminate the fermentation.
What is the next step after soaking and steaming?
making kōji
What is starch made up of?
starch is a large molecule made up of lots of sugar molecules all linked together.
Briefly, what is kōji?
- a mould which creates starch-converting enzymes. The mould is called kōji mould.
- The mouldy rice is called kōji
Why kōji is needed in making sake?
- kōji contain the chemical (enzyme) which can break up the starch into sugars, then the yeast can convert sugars to alcohol during fermentation.
Where can we find the enzymes to convert starch to sugar?
- in the natural world
- any living thing that can digest starch has these enzymes
- the outer part of cereal grains (rice, malt) also have these enzymes
Briefly, what is enzyme?
An enzyme is a kind of protein that trigger the chemical reactions to convert starch into sugar
do we need a large amount of enzyme to convert large amount of starch into sugar?
No, only a small amount of the right enzyme are needed to trigger the chemical reactions, since it won’t be used up during the chemical reaction.
Why beer can convert starch into sugar without kōji?
beer uses unpolished grains that can be malted to release the enzymes in the grains.
What is the ratio of kōji to rice used in sake brewing?
20-25%
What is the ideal condition for kōji mould to grow?
- high humidity
- warm - temperature between 33C - 38C
When does the production of kōji start?
After the rice is taken out of the steamer
What are the four steps for making kōji?
1 - cooling
2 - inoculation
3 - initial mould growth
4 - controlling and stopping the mould growth
Describe what cooling does:
The steamed rice that will become kōji is cooled down to the right temperature.
Describe the inoculation process:
- the cooled steamed rice is transferred to the kōji room, spread out thinly over a table.
- kōji mould spores are sprinkled on the rice.
Describe the initial mould growth process:
- the warm and humid conditions in the kōji room encourage the spores to grow into mould
- the mould spreads and grows over all of the grains
- the rice is thoroughly mixed to ensure the growth of mould is even.
Describe “controlling and stopping the mould growth”:
- the rice with mould is transferred to racks in a cooler, less humid location in the kōji room
- the aim is to control the condition in order to slow down the mould growth to achieve the exact amount of mould grown on each grain
- Utlimately, the mould growth is stopped when the rice is moved to the coolest and driest part of the kōji room.
How long does the kōji production take?
about two days