Experiment 3 Whipping Cream

To show the effect of solid and liquid fat on foam stabilization. 

Separate the whipping cream into three portions (A, B and C), each in a separate bowl. Keep A at room temperature. Add a teaspoon of liquid oil to B, and then chill both B and C (and the whisk) in the freezer for about 15 min. Then whip each of them and compare how easy it is to create a stable foam. 

We saw in Chapter 4 that ice cream mix must contain a certain amount of solid crystalline fat to create a stable foam. The same is true for whipping cream. Keeping the cream at room temperature (A) or adding liquid oil (B) reduces the proportion of solid fat present and makes them harder to whip than C. Some air can be whipped into A and B because the milk protein can also stabilize air bubbles. 

Whipping (churning) cream at warm temperatures leads to complete, rather than partial, coalescence. This results in the formation of large fat particles and eventually produces a fat-continuous material. This is how butter is made, and is the reason why excess fat coalescence during ice cream manufacture is known as buttering . 

To show that solutes lower the freezing point. 

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Massachusetts General Hospital in 1845. The first patient came out of anesthesia too soon, and Wells s discovery was not fully understood or appreciated. Wells continued his experiments with anesthetics and later became addicted to the anesthetic chloroform. Sadly, he committed suicide as a result of his chloroform addiction. Though nitrous oxide was not appreciated at its first public hospital demonstration, it is still widely used today as an anesthetic, particularly in combination with other volatile anesthetics during surgeries. Likewise, nitrous-oxide use as a recreational drug has continued from the early nitrous-oxide capers to the present day, with the use of whipping-cream-propellant whippets and nitrous-oxide balloons and canisters. 

Use of nitrous oxide as a recreational drug occurs in high degree among medical and dental students of whom 10% to 20% have reported experience with the drug. Nitrous oxide is also commercially available as small cartridges of gas used by restaurants to make whipped cream. These are known colloquially as whippets. Smaller volumes of nitrous oxide are found in whipped cream cans available in grocery stores. 

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