Food Technology Glossary

An unbroken chain of refrigerated storage and transport that keeps a food cold from the time it is produced until it reaches the customer.

The slowest-heating location in a container, where lethality accumulates least during thermal processing.

The first stage of drying, in which free surface water evaporates at a steady rate and the surface stays at the wet bulb temperature.

The moisture content at which drying shifts from the constant rate period to the falling rate period.

A process combining mixing, shearing, heating and forming in a screw barrel, forcing material through a die. High-temperature short-time extrusion cooks and expands.

The deposition of protein, mineral or burnt-on residue on heat exchanger surfaces during processing, adding a thermal resistance and restricting flow.

The temperature at which an amorphous solid changes between a rigid glassy state and a rubbery state.

The section of a continuous pasteuriser that provides the required residence time at process temperature.

Forcing a liquid at high pressure through a narrow valve to break dispersed droplets into smaller ones, stabilising the emulsion.

Smooth, ordered flow in parallel layers, occurring at low Reynolds number, with a parabolic velocity profile in a pipe.

The logarithmic average of the temperature differences at each end of a heat exchanger, used because the difference varies along its length.

A fluid whose shear stress is directly proportional to shear rate, so viscosity is independent of shear.