Introduction: the principles of infrared heating Sir William Herschel discovered infrared – or heat radiation – in the 1800s when he was attempting to determine the part of the visible spectrum with the minimum associated heat in connection with the astronomical observations he was making

Preventing the loss of vitamins and nutrients in foods is a paramount concern at all stages of food processing involving heating. One example of the critical need for retaining vitamins is to nourish hospital patients who require vitamins to recover from the stress of illness or surgery.1 This issue has invoked recent studies

Generally, the effects of microwave energy can be classified as either ‘macro￾scopic’ or ‘microscopic’. When the energy is used for heating food the effect is macroscopic and results in a specific heating pattern. However, the causes of certain features are due to microscopic effects, i.e. to physics at the atomic level

‘Genetically modified food’ has become the object of a heated debate by con￾sumer activists and replaced irradiation’s leading role as a target. In this debate the term irradiation is frequently confused with radioactive contamination, espe￾cially after the Chernobyl accident. The allegation is made that the nuclear indus￾try needs food irradiation badly in order to find some use for the waste from

Modified atmosphere packaging (MAP) may be defined as ‘the enclosure of food products in gas-barrier materials, in which the gaseous environment has been changed’ (Young et al, 1988). Because of its substantial shelf-life extending effect, MAP has been one of the most significant and innovative growth areas in retail food packaging over the past two decades. The potential advantages and disadvantages of MAP have been presented by both Farber (1991) and Parry (1993), and summarised by Davies (1995) in Table 16.1

The modern frozen food industry was started by Clarence Birdseye in America in 1925. As a fur trader in Labrador Birdseye had noticed that fillets of fish left by the natives to freeze rapidly in arctic winters retained the taste and texture attrib￾utes of fresh fish better than fillets frozen in milder temperatures at other times of the year. Frozen foods were available before Birdseye’s pioneering innovations, but they were of poor and uncertain quality. Birdseye’s insight was that speed of freezing is crucial to retain quality and he was the first to develop machinery

Extrusion cooking is a relatively recent form of food processing. Forcing material through a hole is the process of extrusion. Sausage extruders were devel￾oped in the nineteenth century as simple forming machines. Eventually pasta was produced in extruders. Flour and water were added at one end of the machine

The domestication of different grasses, all members of the monocotyledonous family Gramineae, was a seminal event in the history of mankind. The cultiva￾tion of these plants led to the generation of agricultural surpluses. These in turn enabled societies in different parts of the world to make the transition from a nomadic or semi-nomadic lifestyle to one based on communities living in per￾manent settlements

Frying, especially deep fat frying, has become the most popular food prepara￾tion technology during the last five decades. The reason is that the preparation is easy even for less experienced cooks, the procedure is rapid, and the finished product is highly palatable. In the frying procedure, fat is the medium of heat transfer. Two main frying methods exist, namely shallow frying and deep frying

The taming of fire, permitting the thermal processing of vegetable foodstuffs in particular, extended enormously the number of natural products that could be used as foods by humans and gave a tremendous impulse to the extraordinary dif￾fusion and development of the human population in almost every region of the world (De Bry, 1994). Foodstuffs can be roughly divided in two classes, those that are or are not edible in their raw form. The most important naturally edible foods are meat and milk, which are heated mainly for eliminating dangerous microorganisms, and some fruits, used by plants to attract animals for diffusing