How is Sake Made?

The taste of sake can be best described as complex, especially when dealing with the more premium brands. Such complexities can only be attributed to a brewing process perfected over the span of many centuries.

In this article, we will take a closer look at how sake is made, but before we get into that, we will first uncover what sake is made from.


What is sake made from?

The quality of the ingredients is one of the things that separates premium brands from the rest, but all types more or less use the same ingredients.

Rice

Rice is essential because, without it, sake just wouldn’t be sake. But what most people do not know is that any type of rice can be used whether white, brown, short grain or long grain. However, this doesn’t mean that all types of rice are equal because a common trait amongst premium brands is the exclusive use of high-quality white, short, and medium grain Japonica rice.

Koji mold spores

Mold has a bad reputation because it’s an allergen, and some species are even downright toxic. Koji mold spores, on the other hand, is perfectly safe and is an essential ingredient as it converts rice starch into sugar.

Water

Most sake distilleries use only the highest quality water, which is why so many of them are located right next to, or very near a mineral enriched freshwater source. The ideal water is rich in potassium, magnesium, and phosphoric acid because these minerals play a vital role in assisting the propagation process of the yeast and koji mold.

Yeast

Yeast is essential for almost every type of alcoholic drink, but the strain used for making sake is a little different. As a matter of fact, the yeast strain used in making sake has a clear, direct effect on not only the aroma but also the taste of the final product.

Brewer’s alcohol

Most brands add distilled alcohol, but this was something that was never practiced before world war 2. Food shortages during the war demanded that rice farmers grow rice for food consumption instead of for luxuries like alcohol. Distilleries, as a result of these rice shortages, began adding distilled alcohol to their batches to increase their yield.

The war is long over, rice is in abundance again, yet the habit continues to this day but for different reasons. Whereas before it was added to increase output, today, it is added to enhance the flavor.

It’s worth noting that premium sake contains considerably less distilled alcohol than the non-premium brands unless it’s Junmai, which doesn’t use any.

Lactic acid

Japanese sake is naturally sweet. Therefore, lactic acid is added to counteract the excessive sweetness. Other benefits include preserving the flavor and killing germs.


How is sake made?

Now that we know what sake is made from, we will see how all these ingredients come together to create the final product.

Preparing the rice

In the first step of making sake, the rice is prepared by milling away a certain percentage of each rice granule’s outer layer.

But why do this?

Each rice granule has an inner core that consists of pure starch and an outer layer of protein. The less protein makes its way into the sake, the higher the quality. Not only does it give the sake a smoother taste, but it also allows for easier fermentation.

The highest quality sake, Daiginjo, mills up to 50% of their rice granules – which means that each rice granule which goes into the brew is half of its original size. Non-premium brands mill down a lot less, often as little as 10% is removed with the outer 90% remaining.

How is rice milled?

Rice milling is done by machine because it’s an extremely delicate process and can take up to 2 or 3 days to remove 50% of the outer layer.

After the polishing process, rice gets washed and soaked in water. Afterward, the rice undergoes a steaming process before being cooled down and spread out onto a table.

Adding Koji Mold

Koji mold spores are added and mixed into the rice. The batch is covered with cloths to keep the temperature consistent and then left for 48 hours while the mold grows.

The purpose of adding koji mold spores is so that the enzymes produced by the mold can transform the rice starch into sugar. And remember how the rice was soaked to absorb water? The reason behind that is so that the mold can grow faster because it needs dampness or a water source to grow.

Fermentation

Fresh spring mineral water and yeast are mixed into a special container. Earlier I mentioned the importance of the quality of the water used in making sake because up to 80% of every bottle consists of water alone. Yeast strains play just as much of an important role, and there are only a handful of strains used by sake manufacturers.

Koji rice is carefully added bit by bit over a couple of days to ensure that the yeast doesn’t get diluted too fast.

This is the fermentation process – where the yeast turns the sugar into alcohol. Temperatures within the container are carefully monitored and controlled, and all mixing is done by hand over 21 days.

It’s also during this stage that lactic acid and distilled alcohol gets added to the batch.

Pressing

Once the fermentation process is complete, it’s time for pressing. It’s where they extract the liquid from the mash, and it can be done either by machine or hand.

The mash is poured over cloth bags so that the liquid drips through while the mash stays behind. To make cloudy sake, a different cloth is used, which allows for some of the rice particles to make their way into the liquid. That is how cloudy sake gets its cloudy appearance.

It’s a rather special day at any sake distillery when a batch is complete and you will often find employees trying it out. And if you are ever lucky enough to visit a sake brewery on a pressing day, you will be able to taste the batch for yourself.

The final stage

Once the sake is ready, it either gets bottled directly or placed into storage to be aged, depending on the brand.


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