Lars Preuss is Strategic Manager, Chemistry Laboratories, Nexus A/S, which is the R&D company for Palsgaard A/S. He holds a M.Sc. and a Ph.D in chemistry from University of Southern Denmark and has more than 15 years of experience in emulsifier development. His email is firstname.lastname@example.org
E473 explained - request from reader
Within a week of its launch Emulsifiers for Good has received its first request for more information about emulsifiers. The reader wanted to know about the emulsifier known as E473, its ingredients and its potential for inhibiting the growth of microorganisms in milk. Emulsifiers for Good approached me and asked me to share my views on E473, which I am happy to do:
The food emulsifier class covered by E473 are sucrose esters of fatty acids, in which the number and type of fatty acids can be varied, resulting in emulsifiers with different functional properties such as HLB (Hydrophilic-Lipophilic Balance) value and solubility. Globally, there are only few producers, but at least one very common way to manufacture it is by interesterification between sucrose and fatty acid methyl- or ethyl esters. You can learn more about the legal specification, applications and more on the official site of The European Food Emulsifiers Manufacturers Association (EFEMA) under the menu item EFEMA Index of Food Emulsifiers. Check out page 83 which has additional information on E473.
The antimicrobial properties of sucrose fatty acid esters have been described in literature* for different applications such as fruit coatings and canned coffee. It functions by destabilization of the target organism cell membrane, thus initiating uncontrolled diffusion of ions and other molecules over the cell membrane leading to ceasing of the organism. The antimicrobial effect is depending on the degree of esterification and the fatty acid in the sucrose ester. Different target organisms such as gram negative bacteria, gram positive bacteria and fungi have different susceptibilities to sucrose ester and even to different variants of this emulsifier. I am not aware of the specific antimicrobial functionality in milk, but it is very likely that it will have some effect depending on the microorganism present.
* Emulsifiers in Food Technology, 2nd edition. Editor Viggo Norn, (pages 147 - 180)