So you have an open container of doenjang that has been in your fridge longer than you can remember and you’re wondering if you can safely use it to make doenjang-jjigae.
Maybe your grandma gifted you a jar and told you it came from her grandma, and you’re thinking, “This can’t possibly still be good after all that time.” “Does doenjang go bad?”
Incredible as it may sound, traditionally prepared doenjang is good indefinitely. As for store-bought versions, recommendations vary on how long it will stay fresh.
Read on to look at the differences in how traditional and commercial doenjang are prepared and the best way to store them for the best result.
What’s Doenjang Made of?
Doenjang, a thick, fermented soybean paste, is a byproduct of making soy sauce. It starts with meju; big blocks of ground-up boiled soybeans that are allowed to hang outside for 1 to 3 months to start the fermenting process. (*)
The blocks are then put into traditional clay pots and covered in a salty brine solution. Here, they ferment for another few months while the solids and liquids separate. The end result is soy sauce and doenjang.
So does doenjang go bad? In most cases, indefinitely. With commercial brands, though, you may want to consider a few things.
Good Bugs Make It Better
Here’s something really cool about the fermentation process; it’s really a way to preserve food and make it safer to eat if it’s being stored for a long time. See, salt is a preservative, so, covering the crushed soybeans in a very salty brine preserves them. (*)
While in the brine, fermentation creates lactic acid bacteria which essentially eat up any harmful bacteria like Bacillus cereus, Campylobacter, and Salmonella. Meanwhile, probiotic bacteria are created that improve your digestion and enhance your health. (*,*)
So, if fermenting preserves food and the process kills the bad bacteria that can make you sick, then it can’t go bad, right? Well, let us elaborate just a bit because, along with traditional fermenting, you can buy doenjang at the market and there are differences that can affect how long it stays fresh.
The Proof Is in the Process
In addition to soybeans, traditional soybean paste will include water, sea salt, and dried chili peppers and jujubes (a small fruit that tastes like a date and adds sweetness to the soy sauce and doenjang.) With the fermenting process we described above, it can take 3 to 6 months to make.
Most modern, store-bought versions of doenjang use a fast production method that includes the basic ingredients of soybeans, salt, and water, but adds extracted alcohol.
They make the process faster by creating a starter culture, called a koji, in grain starches and then adding that to the cooked soybeans to speed up fermentation.
Everything is then ground into a smooth paste and packaged for sale at the store.
How Long Does Doenjang Last?
Traditional doenjang can stay safe to eat indefinitely as long as it’s stored properly (we suggest a traditional clay jar.)
If it’s from the store and was prepared in a factory, it’s safe to assume it will start to discolor or lose texture quality and flavor in about 4 months.
Sometimes, it may last a year or more, but we prefer to err on the side of safety. Either way, it’s so yummy and versatile, it’s usually gone before we can test how long it stays fresh!
Which Is Safer, Traditional Doenjang or Store-Bought?
So, traditional and industrial doenjang are similar. They both use soybeans, salt, and water, but the fermentation process of traditional doenjang gives it a much longer shelf life. If stored properly, traditional doenjang can be kept indefinitely.
Still, there are some things to look for. The top of the paste may turn black. This is not spoilage, but a result of exposure to oxygen, and can be mixed back into the rest of the paste. If a white mold forms on the top, it can be removed and the remaining doenjang can still be safely consumed.
The shorter fermentation process and different ingredients in commercial products will affect how long your store-bought doenjang stays fresh. You should keep store-bought doenjang refrigerated in a tightly-sealed container.
Some say, if kept refrigerated, your average commercial fermented soybean paste should last a year and, sometimes, more. There are many varieties, though, and the ingredients vary by brand.
We think it’s safest to use up store-bought brands within 3 to 4 months of opening.
Doenjang is fermented; a process that produces beneficial bacteria and kills harmful ones.
Doenjang can be traditionally or commercially prepared and the fermentation method used can affect the length of time it remains fresh and safe to consume.
Commercially prepared doenjang is safe to consume 3 to 4 months after opening as long as it is refrigerated in an air-tight container, and could be good for up to one year.
Traditional doenjang is safe to consume indefinitely, though it can become discolored with exposure to oxygen. Like cheese, it can also develop mold on the top that can be removed allowing safe consumption of the remaining paste.
Below are some of the answers to the most commonly asked questions about doenjang:
The Final Word
While it doesn’t necessarily “go bad”, we recommend keeping store-bought doenjang refrigerated in an airtight container. It’s versatile and great with, and in, so many dishes.
If you use it regularly, it probably won’t last long anyway. But if it’s still around after 3-4 months, it may be discolored or taste off. If that happens, we say, “toss it.”
Under the right conditions, traditionally fermented doenjang does not “go bad.” It can change color and the taste may become more “sour” or more intense. But the fermentation process keeps harmful bacteria at bay and renders even doenjang that has been passed down for generations, safe to eat. In this case, our vote is to keep it and enjoy it!