Unilever: Food for thought

20-03-2013

When a tub of ice cream is transported, stored and even taken out of your freezer, temperature changes may destroy the microstructure of the ice crystals and cause recrystallisation that spoils the sensory experience. Food giant Unilever has used high-resolution tomography at the ESRF to get round the problems of temperature abuse.

  • Share

Results obtained at the ID19 beamline in 2009 revealed the variations in the microstructure of ice cream samples in a series of 3D images with a voxel size of just 0.56 µm, leading to improved products.

 

More recently, a Unilever team used the ESRF to tackle the saturated fatty acids in foods. A common way to provide texture to oily food products such as margarine and chocolate is to introduce a network of small triglyceride crystallites, which are rich in saturated fatty acids that raise blood cholesterol levels and contribute to the risk of heart disease and strokes. Researchers at Unilever discovered that a particular mixture of cholesterol-lowering plant sterols, g-oryzanol with b-sitosterol, could provide a healthier alternative. The molecules in the mixture assemble very differently compared to molecules in a normal crystal with 3D long-range order, and the company chose to come to the ESRF to investigate its structure. “The ESRF covers all of the length scales involved in this mixture,” explains Unilever research scientist Ruud den Adel. Small- and wide-angle X-ray scattering at the ID02 beamline revealed a network of tubules in samples of sunflower oil that form rapidly when cooled below the melting point of the gel. 


Unilever spends almost €1bn per year on research and development, and is using the ESRF for several applications, says research scientist Gerard Van Dalen. “The objective of our latest study is to understand and improve the quality of freeze-dried vegetables after rehydration by assessing the multi-length scale pore structure and modelling its impact on the rehydration behaviour,” he says.

 

Matthew Chalmers

 

 

This article originally appeared in ESRFnews, March 2013. 

To register for a free subscription and to rapidly receive the current issue, please go to:
http://www.esrf.fr/UsersAndScience/Publications/Newsletter/esrfnewsdigital

Top image: Unilever studied variations in the microstructure of ice cream at the ESRF's ID19 beamline to get round problems of temperature abuse. Image credit: I, ElinorD, creative commons