Agar Agar Uses

Agar Agar was first introduced from Asia to Europe in the 1800’s and began to be used as a gelling agent in the food industry at the start of the 20th century.

Agar contains agents which will form gels at approximately 38°C, however (unlike gelatine proteins); once an agar gel is formed it will not melt below 85°C. This property allows the creation of “hot gels”. Agar is a source of fibre and can form gels in very small percentage proportions usually between 0.2% -1.5%, (i.e. 0.2g -1.5g or Agar Agar per 100g of liquid). The gelling power of the agar-agar is equivalent to eight times that of animal gelatine.

 

For use, whisk the powder into the selected liquid while cold & heat to 80°C, for ease the liquid can be heated to boiling point. *

Remove the liquid from the heat & rest to set the gel. Gelling will occur at room temperature (below 38°C) but it is advisable to store dishes gelled with agar in the fridge. Once cooled agar gels can be cut & shaped into sheet wrappings or coatings, or cut\diced into pieces for a contrasting flavour addition to a dish. In hot dishes the gels can be heated to 80°C

 

*If the flavour of a product will be affected by heat it is not necessary to heat\boil all of the preparation: (see lime fluid gel below); it is usually possible to boil a small quantity of the selected liquid and blend it thoroughly with the rest on absorption

 

The gelling ability of agar agar is affected by the acidity or alkalinity of the ingredients it is mixed with so the required quantities of agar powder in a recipe will vary depending on the liquid selected. More acidic foods, such as citrus fruits and strawberries, may require higher proportions of agar to enable setting & some ingredients such as rhubarb chocolate & spinach (which contains oxalic acid which breaks down the gelling ability) will not form stable gels.

 

Recipes containing; kiwi fruit, pineapple, fresh figs, paw paws, papaya, mango or peaches may require recipe reformulations to enable setting. If unsure as to the setting ability of a gel, test a small amount on a cold saucer – it should set in around 30 seconds, if not more agar may be required or if too firm – extra liquid.

 

As an average guideline 1g of agar-agar will gel 100ml of liquid (1%). Dilute the powder in the liquid, and boil the whole preparation for 1 min to produce a firm temperature resistant gel.

 

Example Recipes:

 

Basic Gel

100ml flavoured liquid (i.e. stock, fruit or vegetable juice)

1gm agar agar

Whisk the powder into the cold liquid & bring to the boil.

Cool to set.

 

Any variety of finely chopped flavour additives may be added to the gel before setting (chopped herbs etc..)

The addition of a small amount of glycerine (1gm per 100ml of liquid), will give a greater flexibility to the finished gel if it is to be cut for wrapping &/or prevent the gel from dehydrating & cracking if preparing in advance.

 

Vinaigrette Sheets

When setting gels with an acid content a higher % of agar agar is required.

 

100gm rice vinegar

300gm spring water

45gm sugar

5gm glycerine

16gm agar agar (2.6%)

1gm salt

150gm olive oil

Whisk together vinegar, water, sugar, agar agar & salt & bring to the boil.

Remove from the heat & incorporate the olive oil with a stick blender.

Spread a thin layer onto a baking sheet. Cool & cut to shape.

Green Tea Gel with “Nut Milk” Sauce.

For the gel:

1 tbsp green tea powder

2gm agar agar

50gm caster sugar

350ml water

For the milk sauce:

75ml condensed Milk

100ml milk

1gm xthanthan gum

1/2ml En-Place almond\hazelnut or pistachio flavour drop

Ground toasted nuts or praline to garnish

Method:

Bring tea powder, sugar, agar agar & water to the boil over a medium heat while stirring.

Cool & allow to gel in the fridge.

Blend together the ingredients for the milk sauce & strain.

Serve the gel & sauce in shot glasses or on tasting spoons sprinkled with nut praline.

 

Honey & Soy Agar Noodles.

250ml light soy sauce

270ml water

125gm honey

45ml rice wine

45ml white wine vinegar

2 star anise, broken

7gm agar agar

Method:

Bring all the ingredients to the boil. Strain.

Pour on to a shallow tray & skim off any surface foam or bubbles.

Cool in the fridge until set.

Remove the gel from the tray & cut into fine noodles

Serve cold or re-heat by warming in a stock base or steamer as required.

 

Cider Apple Gel

125g granny smith apples

125g apple cider

2.5g salt

2.5g sugar

3.5g agar agar

Method:

Peel, core & dice the apples.

Mix the agar powder with the salt & sugar, place everything in a saucepan & bring to the boil.

Lower the heat & simmer gently until the apples are soft.

Blend & strain into a container lined with cling-film.

Chilli to set, turnout & cut into cubes.

 

Fluid Gels

A fluid gel is a blended solution somewhere between a set gel & a sauce.

It is formed by gelling & then blending (un-gelling) a liquid base. Agar agar gels are “sheer-thinning” meaning they can turn to liquid when blended & stay in a liquid state rather than revert to a solid gel again. Sauces of this nature can be formed from almost any liquid. Because they are based on agar as opposed to a starch thickening agent the result is a smooth mouth feel sauce with nothing to hide the clean flavours selected as the base. Technically these fluid gels aren’t actually liquid sauces but a jelly that has been broken down into millions of fragments to give what appears to be a creamy smooth puree or cream. Depending on the finished consistency fluid gels can be spread directly on to the plate from a spoon or squeeze bottle or poured as a sauce, they can be gently heated to 80°C.

 

Basic Herb Fluid Gel

500ml water

Small bunch of selected herb

Salt to taste

5g agar agar

Method:

Wisk agar agar into cold water & bring to the boil.

Add selected herb to blanch, remove from the heat & blend until smooth.

Season & strain in to a shallow tray to cool.

When set, blend (strain to remove any pieces of unbroken gel) to form a fluid gel.

 

Lime Fluid Jel

100ml lime juice

100ml water

100gm white sugar

3gm agar agar

Method:

Bring the water, agar agar & sugar to the boil. Remove from the heat; allow to cool slightly (but not set). Mix in the lime juice. Refrigerate until cold & set. Blend until smooth & creamy, strain & hold at ambient temperature until service.

 

Coffee Fluid Gel

250ml espresso coffee

250ml milk

50g Demerara sugar

5g agar agar

Method:

Mix agar powder & sugar together, add to the liquids & bring everything to the boil.

Remove from the heat & chill until set.

Blend the gel on high speed until smooth, strain & serve.

 

Agar Agar Clarification of liquids

This fast technique developed by Dave Arnold (director of culinary technology at the French culinary institute of America) is fast becoming a standard clarification process in modern kitchens.

1kg liquid (stock, broth, juice, alcohol etc.) at room temperature.3g agar agar (0.3%)

Method:

Pour ½ of the liquid into a pan, whisk in the Agar & bring to the boil, simmer for a few moments to hydrate.

Remove the pan from the heat and slowly pour in the reserved liquid mixing to combine. This will cool the pan liquid, but providing the reserved liquid is at room temperature it should not set it immediately (which would ruin the procedure). Place the now cooling liquid onto an ice bath or chill to set.

When set break up the light gel with a whisk, pour the broken mixture into a double layer of muslin cloth & squeeze gently to release the clarified liquid. If required the gel can be further whisked to realise more liquid.

If any agar particles are forced through the muslin cloth by squeezing the resulting liquid can be further refined by straining through a fine super-bag or coffee filter.