Whipped-cream charger

A whipped cream charger is a cartridge designed to deliver nitrous oxide in a whipped cream dispenser. When nitrous oxide is infused into cream it creates bubbles and forms whipped cream. Nitrous oxide contained within whipped cream chargers can also be inhaled for its psychoactive effects, as nitrous oxide is a dissociative drug. Chargers are often called whippits (sometimes spelled whip-its or whippets), "whip cream bulbs", "whip cream cartridges", or "whippers" by users and the trade. This process was developed in Europe, and name brand chargers are considered to be the best quality chargers for gourmet and other use, due to their strict manufacturing procedures and repeated cleanings during manufacture (to prevent toxic machining oils from remaining in the charger).

Whipped cream chargers are steel cylinders rounded at one end with a narrow tip at the other. They are typically painted silver, lavender, or blue, and nominally 6.3 cm (2.5 inches) long and 1.8 cm (0.7 inches) wide. The chargers' walls are about 2 mm (about 1/16 inch) thick to withstand the great pressure of the gas contained within. Their interior volume is 10 cm3 and most brands contain 8 g of N2O under pressure. Used chargers are non-refillable but 100% recyclable, where steel recycling programs exist.

Culinary use
To use a whipped cream dispenser, one starts by following a recipe &mdash; typically 1 cup of heavy cream, 2-3 tablespoons of sugar, and any flavourings/colorings as desired. The device is capped and one or two chargers are discharged into the unit, depending on its size. These pressurize the device with nitrous oxide and cause the fat-soluble gas to dissolve into the cream, just like carbon dioxide dissolves into water to create soda water. Shaking the dispenser a few times helps the gas dissolve. The dispenser is then ready for use.

When the cream dispenser's valve is opened, the cream is forced out of the nozzle by the high pressure. However, when the pressure is released, the dissolved gas turns to bubbles (see Charles' law) and comes out of the solution &mdash; just like how opening a soda bottle results in the formation of a head of bubbles. These expanding bubbles instantly transform the cream into a frothy, whipped state. Nitrous oxide is bacteriostatic (prevents bacteria from growing) and a charged cream dispenser can be kept in the refrigerator for up to 2 weeks.

Cheaper brands of whipped cream chargers contain less gas, usually requiring the cream whipper's operator to use two chargers where one would normally suffice. Cheaper brands also may not be as clean inside after being filled and sealed, resulting in toxic oil mists being sprayed into the cream (or recreational users' lungs) when the charger is opened and depressurized.

Small whipped cream chargers are intended for low-volume or occasional use, such as home kitchens. For commercial use, there exist regulated tank systems for filling much larger containers and dispensing more whipped cream. These are more economical for high-volume users, such as ice cream shops and dessert caterers.

Chargers are designed to be opened with a device that punctures the thin metal seal at the narrow end of the tube; Whipped cream dispensers have this integrated into the device's cap.

Dissociative use
In order to inhale the gas, recreational users employ a cracker or "breaker", typically machined from brass or constructed from plumbing hardware, to achieve the same result. The escaping gas expands considerably and cools down, which is not a problem in a cream whipper but can result in freezing burns and frostbite if opened directly into someone's mouth. To avoid this, when used for its dissociative effects the gas is generally discharged into a thick walled balloon. It is also possible to inhale the gas directly from a whipped cream dispenser, the dispenser effectively acting as a nitrous bong.

Due to the small amount of gas present in a single charger, usually not much more than a single breath, the effects generally last for only a few minutes. However, many users choose to inhale a large number of chargers over the course of a night to maintain the effects. This is why it is referred to as 'hippie-crack'. Many users experience a "trip" when utilizing multiple chargers.

Balloons containing nitrous oxide are becoming increasingly available at festivals and clubs in the UK. However this practice is not legal as the gas is being sold specifically for inhalation. Under current UK legislation the seller, but not the buyer, can be prosecuted, though this is rare.

Model rocketry use
Chargers can be used as a cheap source of nitrous oxide for small, powerful model rockets. Nitrous oxide breaks down into nitrogen and oxygen at elevated temperatures, such as those found in automotive and rocket engines. It greatly improves combustion by making more oxygen available to the combustion process. Model rockets designed to be assisted with whipped cream chargers can thus fly much higher and faster than conventional designs of the same size.