Boiling water does kill probiotics in miso.
Live probiotic cultures are destroyed at around 115°F, meaning that fermented foods like miso, kimchi, and sauerkraut should be used at the end of cooking if you want to preserve their gut health benefits.
Miso is a traditional Japanese seasoning.
It is produced by fermenting soybeans with salt and kōji and sometimes rice, barley, seaweed, or other ingredients.
At its most basic, miso is a fermented paste that's made by inoculating a mixture of soybeans with a mold called koji (for you science folks, that's the common name for Aspergillus oryzae) that's been cultivated from rice, barley, or soybeans.
Miso is the ultimate reference point for the flavor sensation known as umami. The paste and the soup have a deep savory flavor, with toasty, funky, salty-sweet richness.
This umami flavor forms the base of a lot of everyday Japanese cooking.
Miso paste is used for making things such as sauces, dressings, batters, and soups.
When making sauces, dressings, batters, and soups the miso paste is mixed into the sauces, dressings, batters, and soups.
Miso paste can be eaten cooked or raw but it's usually added to the foods after the foods are cooked but sometimes the Miso paste is added before the food is cooked.
The Miso paste adds flavor to the foods that the Miso paste is used in.
When Miso paste is used in the foods the Miso paste adds a salty umami flavor to the foods.
Most Miso paste is used and made in Japan which is where the Miso paste ingredient has been used since the eighth century or earlier.
Miso paste doesn't really go bad due to the salt content that Miso Paste contains as a preservative.
However overtime the Miso Paste loses it's taste but Miso Paste doesn't go bad but it loses it's quality and taste over the period of time which is a year.
You can keep the Miso Paste longer in the refrigerator which helps to preserve the taste and even when the taste changes the Miso Paste can still be safely used.
But if you want the best results from Miso paste it should be used within a year and then get fresh Miso Paste when needed.
But if you have Miso Paste longer than a year and want to use it you can safely use it although the taste won't be as good.