Modernist Cooking Made Easy (17 page)

So using these specific ingredients in various ways allows you to control the gelling so it only occurs on the outside of the base, and only to a thickness that you prefer.

G
ELLING
A
GENTS,
I
ONS, AND
S
EQUESTRANTS

There are a few things needed to achieve spherification.

Gelling Agents

There are many gelling agents that can be used for spherification. In general, any gelling agent that requires specific ions to gel can be used. In this book we focus on using sodium alginate because it is very effective at both direct and reverse spherification. Once set, it also can be heated above the boiling point without melting, making it very versatile.

However, you can also use carrageenan, gellan, or even pectin depending on what you are gelling and the properties you want the spheres to have.

Ions

In order for the gelling agents to gel they need to be in the presence of calcium or potassium. In order to supply this you add calcium salts. There are several different ones but the most common are calcium chloride, which has a bitter taste, and calcium lactate, which we prefer to use.

Sequestrants

Some liquids you want to use in spherification might already contain calcium or potassium ions. These liquids will not work as they are because the gelling agent will gel instantly. In these cases you need to use sequestrants. Sequestrants basically tie up all the calcium and potassium ions in a liquid so they can’t react with the gelling agent. You can then use the liquid for spherification like you normally would.

Some common sequestrants are sodium citrate and sodium hexametaphosphate. The full use of sequestrants is outside the scope of this book but they are usually used in a 0.1% to 0.2% ratio.

D
IRECT VS
R
EVERSE
S
PHERIFICATION

There are two main types of spherification, direct and reverse. At the most basic level, in direct spherification the gelling agent is in the base and in reverse spherification it is in the setting bath.

While it seems like a minor difference it causes a few changes in how they work. This is because in both methods it is always the gelling agent that gels, never the liquid containing the ions.

Gel Location

The location of the membrane is affected by the type of spherification used. In direct spherification the gelling agent is in the flavored base so the membrane grows inward as the ions reach the gelling agent. For reverse spherification the membrane grows outward, into the setting bath.

Gelling Cutoff

What happens when the spheres are removed from the setting bath is also affected by the type of spherification used. Spheres made with direct spherification will continue to gel until eventually becoming solid. This is because not only is there gelling agent in the flavored base, there is now also some ions. These ions continue to gel the liquid so the spheres must be served in a timely manner.

In reverse spherification the gelling agent is in the setting bath so once the spheres are removed there is nothing else to gel. This means these spheres can be stored for several hours before serving.

Membrane Flavor

The flavor of the membrane will depend on the type of spherification used. In direct spherification the membrane will be made of the flavored base so it will have a more pure flavor.

In reverse spherification the membrane is made up of the setting bath. Often times sugar is adding to the setting bath to make it sweeter.

S
PHERIFICATION
V
ARIABLES

There are several things to keep in mind when using spherification.

Thickness of Flavored Base

If you are not freezing the base before using it then you may want to thicken it slightly with xanthan gum. A thicker base will hold together better and keep its shape in the setting bath. Usually 0.1% to 0.4% xanthan gum will be enough to do the job.

Thickness of Setting Bath

Another variable is the thickness of the setting bath. If the flavored base is denser than the setting bath the spheres may sink to the bottom and form in non-round shapes. Thickening the setting bath to the same thickness of the flavored base will cause them to float, suspended, in the setting bath.

Acidity

Some gelling agents, like sodium alginate, do not work as well with acidic ingredients. This is more of an issue in direct spherification and is something to be aware of if you are trying to make acidic spheres.

Hot or Cold

Many gelling agents can be heated before they melt, and this means that spheres made from them can be heated as well. If you are planning on serving the spheres in a soup or on a hot dish be sure to pick a gelling agent that works well with it.

Please be careful serving spheres that are at high temperatures because they can cause severe burns since many people expect them to be cooler.

R
EVERSE
S
PHERIFICATION
P
ROCESS

I like to start with reverse spherification because I find it much easier to do. In reverse spherification you combine a calcium salt, typically calcium lactate
^[14]
with the flavored base you want to turn into a sphere. You then freeze this liquid in hemispherical or spherical molds, about 25 mm / 1” in diameter.

Technically, you don’t have to freeze the liquid to make the spheres, it just makes the process much easier. When frozen, the spheres have no chance to break apart. It also allows you to create spheres of a uniform size more easily.

Once the base is frozen you make the setting bath. This is done by combining water with the gelling agent and sometimes some sugar. In reverse spherification I prefer using sodium alginate.

The frozen spheres of base are then placed into the bath for 1 to 5 minutes, depending on the thickness of the membrane you want. Make sure the spheres are not touching or they will fuse together.

I recommend starting with one sphere at a time to test out some different setting times. That way you can see which one works best for your specific purpose. In general I’ve found these times work well:

Small Spheres - 2 minutes

Medium Spheres - 4 minutes

Large Spheres - 5 minutes

Thin membrane - 1 minute

Medium Membrane - 3 minutes

Thick Membrane - 5 minutes

Once the membranes have set the spheres are removed and rinsed in a water bath. This bath can be warm or cold, depending on the temperature you would like to serve the spheres. At this point the spheres are ready to be served.

Storing the Spheres

The spheres can be stored for several hours or even overnight in liquid. However, the liquid can leech out some of the flavor so they shouldn’t be left in plain water for more than 15 to 30 minutes. If you know you will be storing them for an extended period of time I recommend setting aside some of the liquid used in the base, before the calcium is added, and storing the spheres in it.

Carbonated Spheres

You can also place the finished spheres into a whipping siphon, with some reserved calcium-free liquid, charge it, and let it sit for several hours to carbonate the spheres.

Reverse Spherification Ratios

For the flavored base a ratio of 1.0% to 3.0% calcium lactate is typically used with a setting bath of 0.4-0.5% sodium alginate.

P
OMEGRANATE
C
OSMO
S
PHERES

My wife and many of her friends enjoy cosmos, especially pomegranate cosmos. Turning the drink into spheres is a great way to add a twist to the drink while still allowing them to enjoy a favorite drink.

If you have a whipping siphon you can elevate these another level. Once the spheres have been gelled place them in the siphon, making sure to stay below the fill line. Add enough pomegranate juice to cover them and seal the siphon. Charge with one canister, and vent it out, this will clear the air out. Charge as you normally would and refrigerator for several hours before venting the siphon and serving.

This recipe will make about 30 to 50 spheres.

Tools Needed

Sodium alginate

Calcium lactate

Immersion blender

Slotted spoon

Hemispherical or spherical molds

A scale with small gram measurements

Ingredients

For the Cosmo Spheres

175 grams vodka, about ¾ cup

175 grams pomegranate juice, about ¾ cup

120 grams cointreau or triple sec, about ½ cup

60 grams fresh lime juice, about ¼ cup

10.6 grams calcium lactate, 2.0%

For the Alginate Bath

1000 grams water

65 grams sugar

5 grams sodium alginate, 0.5%

Combine the ingredients for the cosmo in a bowl using an immersion blender. Spoon the cosmo flavored base into hemispherical or spherical molds and freeze them.

Prepare the alginate bath by placing the water, sugar, and sodium alginate in a pot. Blend well with an immersion blender and bring it to a boil. Set it aside and let it cool.

Fill another bowl with water and set aside for use as the rinsing bowl.

Place the frozen cosmo spheres into the alginate bath, making sure they do not touch each other. Let them set for 2 to 4 minutes. Remove them with a slotted spoon and place them into the rinsing bath. Swirl them gently to rinse off the outsides.

They will last for about 30 minutes in the water bath, or over night in reserved pomegranate juice.

C
RANBERRY
S
PHERES

These cranberry spheres are a great way to add some flair to a turkey dinner. I use a homemade cranberry sauce in them. It is thicker than the liquid in many spheres but it is packed with flavor. If you prefer to use a pre-made cranberry sauce you can thin it out if needed with water, orange juice, or cointreau until it is a good thickness. This recipe will make 25 to 40 spheres.

Tools Needed

Sodium alginate

Calcium lactate

Standing or immersion blender

Coarse strainer

Slotted spoon

Hemispherical or spherical molds

A scale with small gram measurements

Ingredients

For the Cranberry Sauce

170 grams cranberries, fresh or frozen, about 1 12 -ounce package

150 grams sugar, about ½ cup

350 grams water, about 1 cup

1 cinnamon stick

60 grams cointreau or triple sec

For the Cranberry Base

400 grams cranberry sauce

8 grams calcium lactate, 2.0%

For the Alginate Bath

1000 grams water

65 grams sugar

5 grams sodium alginate, 0.5%

Combine all the ingredients for the cranberry sauce except the cointreau. Bring to a simmer at cook until the cranberries are tender and have released their juices. It should take about 20 minutes. Add the cointreau and blend well. Strain the mixture into a bowl and set aside.

Make the flavored base by combining the calcium lactate with 400 grams of the cranberry sauce in a bowl using an immersion blender. Pour the base into hemispherical or spherical molds and freeze them.

Prepare the alginate bath by placing the water, sugar, and sodium alginate in a pot. Blend well with an immersion blender and bring it to a boil. Set it aside and let it cool.

Fill another bowl with water and set aside for use as the rinsing bowl.

Place the frozen cranberry spheres into the alginate bath, making sure they do not touch each other. Let them set for 2 to 4 minutes. Remove them with a slotted spoon and place them into the rinsing bath. Swirl them gently to rinse off the outsides.

They will last for about 30 minutes in the water bath, or over night in reserved cranberry sauce. They can be served hot or cold.

D
IRECT
S
PHERIFICATION

Making spheres with direct spherification takes more practice than with reverse spherification. Both the setting bath and the flavored base are liquid when you combine them so it takes more technique to create spheres.