Polarised neutrons used to measure firmness of food products
21 May 2007 by TNWToday | R³Researchers at the department of Radiation, Radionuclides & Reactors measured the firmness of an emulsion droplet structure by scattering neutrons using a special technique: spin-echo small-angle neutron scattering (SESANS).
If you want firm up a particular food product by creating a particle network, there are several ways to achieve this: particles can be arranged in order; they can be arranged in disorder, or you can create a relatively firm network. This last method is preferable if you don’t want to use many particles (because of cost or health issues).
The key question therefore is how one can verify that a firm structure has been formed. Often the building blocks of food emulsions (margarine, mayonnaise, cheese) are no bigger than 0.1 to 10 micrometers. That is why these food products are opaque, so using a light microscope can be tricky. Most existing techniques require complicated sample preparations with a concomitant risk of artefacts.
R³ researchers have developed a special technique whereby the neutrons’ eigenstates can be split over a distance of 15 micrometer and 30 nanometres after which the neutrons probe a cheese-like product. In essence this technique determines whether the consistency of the product differs along the two eigenstate paths. The structure of the droplet network can be assessed quantitatively by varying both eigenstates.
The results of this research have been published in a paper: Effect of processing on droplet cluster structure in emulsion gels, Food Hydrocolloids 21, 844-854 (2007), authored by Arjen Bot, Franck Duval and Wim Bouwman.
For more information please contact Wim Bouwman at the department of Radiation, Radionuclides and Reactors
