Replaces gelatin
Vegan gelatin substitute: how to use agar agar
Quick answer
- Agar powder
- 1/2 tsp per cup (240 ml) of liquid for a soft set, about 1 tsp for a firm set; brands vary, so check the package
- Flakes or bar
- 1 tsp powder is about 1 tbsp flakes or half a bar
- Method
- boil it in the liquid for several minutes, until no grains remain
- Setting
- sets at about 32 to 40 °C, even at room temperature, and stays solid until about 85 °C
Gelatin comes from animal collagen. The plant swap is agar agar, a gelling agent from red seaweed sold as powder, flakes or bars. It sets liquids into jellies, panna cotta and glazes, but it behaves differently from gelatin: it has to boil, it sets fast at room temperature, and it is much stronger.
Agar and gelatin compared
| Gelatin | Agar agar | |
|---|---|---|
| Made from | animal collagen (protein) | red seaweed (a fiber) |
| To dissolve | warm liquid | boil for several minutes |
| Sets at | fridge temperature | about 32 to 40 °C, even on the counter |
| Melts at | body temperature | about 85 °C |
| Texture | soft, wobbly | firmer, cleaner cut |
| Fresh pineapple, kiwi, papaya | stop it setting | more reliable; cook the fruit to be safe |
How much agar to use
Agar is sold in different strengths, and published conversions range widely. Modernist Pantry, for example, found a one to one swap made panna cotta two to three times firmer than the gelatin original. So treat any conversion as a starting point:
| Set you want | Agar powder per cup (240 ml) |
|---|---|
| Soft, spoonable (panna cotta, mousse) | about 1/2 tsp |
| Firm, sliceable (jelly cubes, layers) | about 1 tsp |
One teaspoon of powder is about one tablespoon of flakes or half a bar. Flakes need longer to dissolve.
Other plant gelling agents
Carrageenan, also from seaweed, comes in two common kinds: kappa sets firm and brittle, iota sets soft and elastic. Pectin sets jams. Puddings thickened with cornstarch or arrowroot need no gelling agent at all.
For a creamy set dessert, set a plant cream or plant milk with agar instead of gelatin.
How to set a liquid with agar powder
You need: agar powder, the liquid to set (juice, plant milk, broth), a saucepan, a cold plate for testing.
- Whisk the agar powder into the cold liquid in a saucepan: start with 1/2 tsp per cup for a soft set, 1 tsp for a firm one.
- Bring it to a boil, whisking, and let it boil gently for several minutes until no grains remain.
- Test it: drip a spoonful onto a cold plate. It should set within a few minutes. If it is too soft, add a little more agar and boil again.
- Pour it into molds or glasses. It sets as it cools, in the fridge or on the counter.
When it works and when it fails
Works well
- Fruit jellies, panna cotta, set custards and layered desserts
- Glazes and jellies that must stay firm in warm rooms
- Vegan cheesecakes and mousse cakes that need to slice cleanly
- Desserts you want to unmold and keep standing outside the fridge
Fails or disappoints
- A one to one swap by volume gives a much firmer, more brittle set than gelatin
- The soft, melt-in-the-mouth wobble of gelatin is hard to copy
- It must boil; stirred into warm liquid it never sets
- Very acidic liquids, such as lemon or lime juice, set weaker and need more agar
Questions
What is agar agar?
A gelling agent made from red seaweed. Gelatin is made from animal collagen, so agar is the usual vegan substitute.
How much agar replaces one envelope of gelatin?
Sources disagree, from about 1/4 tsp to a full tsp of agar powder per tsp of gelatin, because brands differ in strength. A safe start is 1/2 to 1 tsp agar powder for each cup of liquid, then a cold plate test.
Can I use fresh pineapple or kiwi with agar?
Fresh pineapple, kiwi and papaya stop gelatin from setting, because their enzymes break down protein. Agar is not a protein and is more reliable, but some cooks report soft sets with fresh pineapple, papaya and mango, so cook the fruit briefly first to be safe.
Does agar need the fridge to set?
No. It sets as it cools to about 32 to 40 °C, so it firms up on the counter, and it does not melt again until it is heated to about 85 °C.
My agar dessert is too firm. Can I fix it?
Yes. Agar can be melted and set again. Bring it back to a boil with more liquid, then pour it into the molds again.
Related swaps
- Replaces egg whitesAquafaba3 tbsp per egg, 2 tbsp per white. Whips into meringue and binds cakes.
- Replaces heavy creamHeavy creamCoconut cream to whip, cashew cream for sauces, soy milk with vegan butter.
- Replaces milkPlant milksSoy, oat, almond, rice and coconut compared: which to bake with, which for coffee.
Sources
Ratios and temperatures were checked against these pages on 2026-10-10. Where they disagreed, we give the range.
- Substituting agar for gelatin (Cook's Country, America's Test Kitchen)
- The starting guide to replacing gelatin with agar (Modernist Pantry)
- Agar vs gelatin conversion table (Cape Crystal Brands)
- Agar from Gracilaria, training manual (FAO)
- Why can't I use fresh pineapple in Jell-O? (McGill Office for Science and Society)
- Seventeen things you should know about agar agar (Kitchen Butterfly)
Written with AI help, in our own words. Cooking advice, not health advice. Last checked 2026-10-10.