FIBEROPTICS IN THE FOOD-INDUSTRY

Optical fibers enable spectrophotometric and fluorometric measurements to be made with little or no damage in the interiors of semisolid foods, and in pipes and vats of food ingredients. Applications include the assessment of primary products for a quality-based payment to the producer, and the on-line feed-back and feed-forward control of continuous food processing. Ratiometric measurements (light in versus light out) from 400 to 1000 nm are useful for measuring chromophores and light scattering. Autofluorescence may be measured with a dichroic mirror as a beam splitter to enable a single optical fiber to be used for both excitation and emission. Spectral measurements may be combined with spatial measurements to produce wavelength-position matrices with a high information content, and fiber-optic and photodiode array technology for food analysis may in the future merge with video image analysis.