Does Agar Agar Expire? (Read this First!)

Agar-Agar is a gelatinous additive for thickening soups, sauces, and desserts. This powder is made from seaweed and becomes jelly-like form when prepared.

Since Agar Agar is not something you’d frequently use for cooking, it’s important to know its shelf life.

So, does agar agar expire?

Agar-Agar or agar doesn’t go bad. The agar powder used as a thickening agent has no expiration date. However, experts recommend using agar agar before the use-by date or within a fixed period after purchase. Old agar powder that wasn’t kept dry may lose its freshness and won’t thicken dishes properly. 

This blog post has information on agar agar shelf-life and how you can prevent agar from spoiling.

 Let’s get started.

Does Agar Agar Expire? 

Agar agar is shelf-stable and doesn’t expire. This gelatinous substance isn’t something that reacts chemically. Unlike most other food additives and gelling agents, agar agar doesn’t go bad or lose its efficacy over time. 

If agar powder doesn’t get wet, it should work fine. Many people use expired agar and get good results. You can also try to make a get and see if agar powder dissolves as expected.

Do Agar Plates Expire or Go Bad?       

Yes. Commercially-available agar in Petri dishes or agar plates has a shelf-life shorter than shelf-stable agar powder, typically ranging from 30 to 90 days.

As long as the petri dishes are kept closed and in the cold, they’ll last a long time. The limiting factor is how long before they begin drying out. The agar gel is mostly water; when it loses too much water, it begins to shrink away from the walls. A completely dried agar gel looks like a transparent potato chip.

Agar Agar History, Uses, and Shelf Life – Everything You Need to Know!

For those who do not know, gelatin is extracted from animal skin, ligaments, and bones. And if you object to that, then Agar-Agar is a good option for you. Agar is derived from red algae and is a Vegan alternative to gelatin. 

An innkeeper named Mino Tarozaemon accidentally discovered agar agar in Japan. He was serving seaweed jelly noodles to some guests. The seaweed had to be dried and boiled for many days, so this dish was only for the rich. But sadly, Mino had to throw away a lot of leftovers that night. When he woke up in the morning, he saw that the noodles had dried up overnight into a paper-like substance.

And that’s how our modern-day agar agar was discovered.

Agar Agar Varieties

Agar-agar is sold as powder, bars, flakes, and strands. The seaweed is boiled into a gel, dried, and then crushed to form agar flakes, powder, or freeze-dried into bars. The agar powder is cheaper than flakes and dissolves almost immediately, whereas the flakes need more time to blend until smooth.

You can use the agar powder in a 1:1 ratio when substituting for gelatin, and when using agar flakes, add 1/3 the amount of gelatin. The agar bars and sticks can also be processed into powder form in a blender or food processor. Similar to gelatin, you’ll find flavored and colored versions of agar.

Agar-Agar Uses

In cooking, agar-agar is used as a vegan substitute for gelatin in many dishes, including puddings, jellies, and mousses. You can also use agar agar in ice cream, gummies, and cheesecake. It’s a primary ingredient in the Japanese dessert anmitsu, which requires a mixture of agar-agar, sugar, and water.

Since its discovery, agar powder has been used to make desserts in Asia, but it has also found uses as a gelling agent and a thickener in savory dishes.

Besides agar powder’s culinary uses, agar is also used in labs as a culture medium.

How to use agar?

Agar Strands or Flakes

The best way to use agar strands or flakes is to soak them in water for 10-minutes and then bring them to a boil while stirring until agar dissolves completely. Add color, flavor, coconut milk, or fruit extracts as the recipe calls.

This way, you’ll know when the agar has dissolved completely. If there are grainy bits of agar sticking to the bottom of your pan, the jelly won’t set properly.

Agar Powder

If you’re using agar powder, mix all the ingredients along with the powder and let the mixture sit for 5-minutes. Never mix agar powder with warm or hot water as it will become impossible to dissolve. Stir agar powder into room temperature liquid and then bring it to a boil, making sure the agar has dissolved. Pour into separate molds and let it set.

Although Agar jelly sets at room temperature, it is best served cold. Let agar set at room temperature and then refrigerate before serving cold.

Now that you know all you need to know about Agar-agar, go make yourself something delicious with it!

Tips For Working with Fresh Agar Agar

1. A little agar agar goes a long way, so measure your ingredients!
2. ‘Blooming’ and bringing agar to the correct temperature are key factors for gelling.
3. Agar needs to ‘bloom’ in liquid first for 10 minutes before applying heat to activate the gelling agent in the agar. Always heat agar to 85-90°C, or it won’t melt, but make sure to not let it boil past the melting point as this can harm its gelling ability.
4. Stir the agar constantly until it dissolves to avoid it sticking to the bottom of your pan.
5. The acidity of the ingredients will impact the agar’s gelling ability. High acidic content will require more agar powder to set. Agar gel doesn’t set if exposed to the enzymes of tropical fruits like kiwifruit, peaches, papayas, pineapple, mangoes, guavas, and figs. If you are using these ingredients, heat them before adding agar to allow the recipe to set successfully.
6. Agar sets well at room temperature, so pour the agar mixture into a serving dish while it is still hot.
7. Jelly made with agar will ‘sweat’ when in humid weather. To prevent this, you can dissolve 1 tsp of corn starch with the agar into the liquid that you are cooking agar in.

Add agar into your cooking and try out different ways in which you can use it today!

Frequently Asked Questions

Does agar agar spoil?

No. Agar agar doesn’t spoil if you store it properly. Agar powder has a long shelf-life, but it may lose some gelling strength if stored in harsh conditions. You can prevent agar agar from spoiling by limiting exposure to humid air, sunlight, and extreme temperatures.

Can you put agar agar in the fridge?

Yes, you can store agar agar in a refrigerator because most bacteria cannot grow in cold temperatures.

How long can you store agar?

If the agar jelly was maintained at 4C, you could use it for two weeks. After 2 weeks, you’ll notice some dehydration. Store agar plates upside down in a fridge or cold room. If they are stored in a room, check the plates for condensation in the lid every few hours. If you have kept the agar plates upside down and notice condensation in the lid, there must be a heat source above driving water out of the agar and into the lid.

Where Can I buy Agar-Agar?

You can find agar-agar in the natural food section of the supermarket, in Asian groceries, and online. Agar flakes are more expensive than the agar powder. If you’re looking for the cheapest option, go for agar strands.

What’s the best place to store agar agar?

You should store all forms of agar-agar in an airtight container in a cool, dry spot like the pantry, where it will stay fresh for a long time.