Designed to investigate the energy value of food stuffs e.g peanuts. A peanut is burnt in the crucible using heat from the electrical element, which is supplied with electricity from a low voltage power supply. Connecting a joulemeter or voltmeter and ammeter allows the value of energy required to burn the peanut to be recorded. The glass vessel when filled with water provides 2 functions: as an insulator and a heat exchanger to measure the resulting rise in temperature. A filter pump is connected to the top of the spiral copper tube to draw off the combustion products. For a more efficient burn, the air inlet tube in the base can be connected to an oxygen supply. A metal stirrer is supplied to agitate the water sufficiently to ensure uniform temperature measurement.
By measuring the total rise in water temperature, total energy supplied and by using the specific heat capacity of water, the additional energy transferred from the peanut can be determined.
The unit consists of 2 main parts: The base plate with crucible and heating element, the glass vessel with the spiral copper tube.
Equipment needed:
Power supply, joulemeter or voltmeter & ammeter, thermometer, filter pump, rubber tubing and a retort stand. Optionally a source of oxygen can be used to ensure complete oxidisation.