Vol. X · Emulsions, Foams and Gels Plate 7 of 11whipped cream, cream, fat globules, cold, overrun, butter, Chantilly, whipping cream, temperatureMT

Whipped Cream.

Cream straight from the fridge doubles in volume in three minutes. The same cream at room temperature barely froths, and three minutes too long turns it into butter.

Whipped cream is a foam held up by fat, not protein. Cream with at least about 30 % fat is full of fat globules, each wrapped in a thin membrane (X.1). Whisking batters them; their membranes tear, and where they meet the surface of a bubble the partly solid fat sticks to the air and to other globules. A network of clumped globules forms around the bubbles and holds the foam stiff — but only if the fat is partly crystalline, which means cold (IX.2).

Warm cream, its fat mostly liquid, smears rather than clumps; it will not hold air. Keep whisking cold cream past stiff peaks and the clumps grow and join until the fat separates from the liquid: butter and buttermilk, which is exactly how butter is made. The workshop whips cream at the temperature you choose.

Below: overrun and stiffness against whisking minutes for cream at fridge temperature and yours, with the point where it turns to butter, and the solid share of butterfat at your temperature (colloid bench, teaching model).

What you will learn

Explain how fat holds a cream foam.
Explain why cream must be cold.
Stop before it turns to butter.
Choose cream for whipping.

Workshop

Colloid bench, a teaching model: cream of 35 % fat whips best below 10 °C and not at all above 18 °C; overrun rises over about 3 minutes to near 100 %; past about 5 minutes the fat clumps into butter. Butterfat solid share from the course melting curve (IX.2).

Cold cream, watchful eye

At 5 °C, where about 70 % of the butterfat is solid, cream whipped three minutes reaches about 100 % overrun in this model: double its volume. At 15 °C, the same three minutes gives only 38 %, and at room temperature, with about 16 % of the fat solid, it barely froths. So chill the cream, and in summer the bowl and whisk too.

Choose cream of 30–40 % fat (whipping or double cream); single cream and milk have too little fat to build the network. Add sugar and vanilla near the end for Chantilly cream. Stop at soft peaks for folding into mousses and at firm peaks for piping; if it starts to look grainy, stop at once and fold in a spoonful of liquid cream to smooth it. Whipped cream weeps as it stands; a little mascarpone, yoghurt or gelatin (X.8) keeps piped cream on a cake for a day. Keep whisking past grainy and you have made butter — not a waste: strain it, rinse it in cold water and salt it.

At the stove

Whip two small bowls of the same cream, one straight from the fridge and one left out for an hour. Compare the volume after three minutes. Then keep whisking the cold one until it suddenly separates into butter and buttermilk.

Chantilly cream, sweetened whipped cream, is named after the château of Chantilly north of Paris, where legend credits the seventeenth-century steward François Vatel with it; the name appears in print only in the nineteenth century.

Terms

Fat globule: A droplet of milk fat wrapped in a thin membrane.
Partial coalescence: Fat globules clumping without fully merging, which holds whipped cream.
Chantilly cream: Whipped cream sweetened and flavoured with vanilla.
Buttermilk: The liquid left when cream is churned into butter.

Whipped cream is held by clumped, partly solid fat: whip it cold, and stop before it turns to butter.

Sources

A teaching value chosen for the course: the right order of magnitude and shape, not a measurement of a particular food.
H. McGee, On Food and Cooking: The Science and Lore of the Kitchen, 2nd ed., Scribner, 2004.