Miso paste is a popular ingredient that adds a delicious salty, funky umami flavor to any dish. It is easy to use and can be added to a large variety of dishes, from soups, dressings, sauces, glazes, and even in baking. A great addition to any pantry, miso can last a long time. However, like any food miso can go bad. It may be tricky to identify the signs and know how long it will last. After all, fermented products should last a really long time- right?! Let’s find out.
WHAT IS MISO?
Miso is a fermented paste that is made from soybeans, salt, grain, and koji. It has a salty, funky, earthy flavor that adds depth and umami to dishes. It is thought that miso originated in China around 800 BC, and came to Japan in 500 AD. After all that time, it has become a staple in Japanese cuisine.
The key to miso fermentation is koji. Koji is a type of mold and is also used to make soy sauce and sake. Koji is grown directly on the grain, such as rice or barley. When combined with cooked soybeans and salt, koji starts the fermentation process. The fermentation process can be as fast as a few weeks or happen over several years. It is thought that the best quality miso has the longest fermentation period, but this isn’t true. The best miso has the correct fermentation duration depending on the type of miso.
Miso can be creamy or chunky, similar to varieties of peanut butter. It has a paste-like texture and is very easy to mix into dishes. It dissolves easily and is most commonly enjoyed as miso soup.
As a fermented food, miso is fantastic for gut health. Miso has been linked to several health benefits, such as lowering blood pressure, improved digestion, and a healthier gut. It has even been linked to helping to reduce chronic pain. Something to remember is that it does have a high salt content. If you are on a low-sodium diet, it is best to enjoy miso in small quantities.
DIFFERENT TYPES OF MISO
It is thought that there are up to 1,000 different types of Japanese miso pastes! Miso is specialized by region and is differentiated by the type of grain. The most common type of grain used is rice or barley.
Kome-miso: Miso that is made from soybeans and rice koji. This is the most common type of miso found in the USA.
Mugi-miso: Miso made from soybeans and barley.
Mame-miso: Miso made from soybeans only.
Awase miso: A miso that is made of more than one miso paste. It is most commonly a mixture of the different types of miso listed above.
Each grain can make the most common types of miso: light miso and dark miso.
Light Miso: Sometimes called sweet miso because of the lowered salt content. It can also be called white, beige, or yellow miso. Light miso has a shorter fermentation process. Sometimes also called mellow miso, this is the best type of miso for someone new to using this delicious fermented product.
Dark Miso: Often called red or brown miso, this type of miso has a higher salt content. It is much stronger than light miso so it should be used sparingly. It has a significantly higher fermentation time, up to one or two years.
Miso is available in the Asian section of grocery stores. Sometimes it is also kept in the produce area, next to the tofu products. If you cannot find miso in your local supermarket, it will be available in Asian grocery stores.
HOW TO USE MISO
Good news- miso is an incredibly versatile ingredient, and can be used in almost any dish! It can be eaten raw or cooked. Because it is a fermented food, it is safe to eat raw. It does not require any additional cooking once the paste is packaged for consumption. You can even combine miso with butter to spread on toast for a quick snack.
If you do use miso for cooking, add it towards the end once the dish is cooked. You will risk killing the active bacteria that pack a nutritional punch if you cook miso.
White miso paste is best in lighter dishes, such as miso soup, salad dressing, sauces, or glazes. Sweet miso has become popular in baking, adding an unexpected depth of flavor to sweet treats.
Red miso is saltier and has a much more intense flavor. It is best used in heartier dishes, such as soup or stews. Remember, a little bit of dark miso can go a long way and pack a powerful punch!
As a general rule of thumb, it is best to use white and red miso differently. They are not interchangeable unless you adjust the amount you add to a dish. You won’t want to add 1 tablespoon of red miso to a recipe if it calls for 1 tablespoon of white miso. The red miso would overpower your dish and may become inedible.
HOW TO TELL IF MISO IS BAD
While miso is fermented and has a long shelf life, it can still go bad. It can be hard to know and understand the signs of spoilage.
It is best to keep an unopened jar of miso paste in a cool dry place at room temperature. Do not expose unopened miso to temperature changes, or it could cause the miso to go bad before opening.
The natural taste of miso is salty with a nutty aftertaste. While salty, if you try a small bite, it should still be delicious and palatable. If miso has a sour taste, this is a sign it has gone bad.
Miso should have a salty, nutty aroma that is enjoyable. A good sniff of the miso paste should tell you if it is bad. If it has a pungent, sour smell, it is best to throw it away and start fresh.
Miso can also darken in color when it goes bad. This can be hard to monitor because miso can continue to darken once opened. However, the color should only darken drastically over a short amount of time. If there is a large color change, start fresh.
Lastly, if there are any signs of mold growth, get rid of it. To keep miso as fresh as possible, always use clean spoons when adding or measuring miso. Cross-contamination isn’t dangerous and you don’t need to worry about food poisoning. However, it can affect the taste and the freshness of the miso.
HOW TO STORE MISO
So now that we understand the signs that miso has gone bad, what’s the best way to store it? How long will it last? Here are a few storage tips to keep your leftover miso paste as fresh as possible.
As a general rule, miso should last for up to a year once opened. Red miso has a higher salt content, so it can be safe to eat for up to two years once opened. It is best to always be aware of the expiration date. If you notice your miso has passed the best-by date, it should be fine for a month or two after the date. Any longer, and it is time to start fresh!
Once you have opened miso, the best place to keep it is in the refrigerator. Be sure it is in an airtight container. Sometimes it is helpful to press plastic wrap on opened miso to keep it fresh (just like guacamole). While this is step not necessary, this step can help block air and keep miso as fresh as possible.
If you do not want to keep miso in the fridge, you can also store it in the freezer. Freezing miso is a great way to store miso if you know you won’t get through a whole container before it spoils. It is best to freeze miso in ice cube trays– this makes it easy to use and add to dishes. Freezing miso should not affect the texture or taste.
Most commonly used in Asian cuisines and homemade miso soup, this fermented soybean paste can be added to almost any dish. White and red miso is the most common variety. There are several different types of miso that you can add for an unexpected umami punch. Try adding to soups, vegetable dishes, or even baked goods.