New methodology using synchrotron radiation to characterize fast events in food processing

Type :

Presentation

Pages :

7 pages

Format :

.doc

Published date :

12/04/2008

Category :

Science & technology

Sub category :

Biology

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Summary :

Introduction.
The problem.
1. The mixing of ingredients at higher temperature.
2. The engineer or scientist seeking to control a food process.
Choice of method.
XRD Technology.
1. Production of X-rays.
2. Detector technology.
3. Applications to biological kinetics.
4. Protein catalysis mechanisms.
5. Protein structure/dynamics in solution.
6. Applications to triglyceride crystallization.
7. Classification of lipid crystals.
8. Kinetics of lipid crystallization.
Conclusion.

Abstract

In a typical food process, a hot mixture is made, which is then cooled rapidly. A main result of cooling is a change in physical state and/or molecular structure. Often, a succession of physical changes occurs as the product cools. events occurring at the more rapid cooling rates can be difficult to characterize using common laboratory methods, and there is a pressing need for faster laboratory measurement techniques. The goal of this chapter is to show that X-ray fluxes available today at synchrotron radiation sources make it possible to characterize rapid process events by X-ray diffraction (XRD). Currently, synchrotron X-ray fluxes are up by 3 to 4 orders of magnitude over the best conventional laboratory sources. When used in conjunction with fast electronic detector systems, synchrotron radiation beams can be used to study events occurring on millisecond time scales. Owing to on-going technical developments, the prospect is to be able to characterize events on a microsecond time scale in the near future. Many processed foods start with the mixing of ingredients at higher temperature, often with the formation of an emulsion during mixing. Typically, the mix is then cooled rapidly. In the sequence of heating and coohng, chemical changes may occur, such as disulfide bond formation in dairy products, or the major change may be simply a temperature-induced change of physical state, such as starch gelation, protein aggregation or fat crystallization.