transfer | nano sciences | agriculture & nutrition

Edible coatings for food

Food technology presents whey protein at Hannover Messe



When milk is processed into cheese, a watery, green-yellow liquid is left over: whey. Dried whey or whey powder mainly contains lactose, milk sugar, and high quality protein. In agriculture it is used as feed, and in food production as an additive. An application in food technology is also possible. A research team of the Institute of Human Nutrition and Food Science of Kiel University is investigating, how to produce so-called amyloid aggregates out of those proteins. Those fibres of only a few nano meters can stabilize emulsions or build ultra-thin eatable films that protect food against oxidation. At the booth of Kiel University at the Hannover Messe the working group presents its project.


Whey contains one of the best characterised proteins of all: ß-lactoglobulin. “We know the structure and how it behaves. In addition to that it is readily available" stresses Dr Julia Keppler from the unit of food technology of Kiel University the advantages of her research focus. She uses it to produce fibrils, amyloid aggregates. Due to its special structure and surface activity, these have properties that can be used for food processing.  

At the moment the project team works with liquid interfaces, and stabilising foams and emulsions. The next goal is to produce edible, food-grade and biodegradable solid films which can be used for coating surfaces. For example they could protect food against oxidation. Among other things, they are investigating which functional properties are associated with the different morphologies. Some questions include: How stable are the aggregates during processing? Can they be used to stabilise emulsions? How strongly do the products oxidise?


In order to produce the desired amyloid aggregates from BLG, it is dissolved in acid pH and then kept for five hours in a water bath at 90 degrees Celsius. The procedure destroys the protein's original structure. Small peptides are created which join together to form new structures - long thread-like strands, small balls or worm-like structures.

However, these structures cannot observed with the naked eye or under a light optical microscope. Outwardly, only the somewhat viscous, gel-like solution suggests that amyloid structures are present. The dried final product is a fine white powder, just like the starting product. She uses a whole range of methods to analyse the form and function of the products. "For example, we highlight using a fluorescent dye which specifically binds to certain structural patterns, the so-called ß-sheets, or measure the conformation of proteins at different points in time during the process using infrared spectroscopy”, says Keppler.

From April 1-5, 2019 the working group presents their project at the booth of Kiel University at Hannover Messe (Hall 2, Research & Technology, booth C07). Dr. Keppler gives a talk on Thursday, 12 am and 2:30 pm.

The work is part of a priority programme of the German Research Foundation (DFG) (SPP 1934 - DiSPBiotech). The Kiel sub-project is led by Dr Julia Keppler, together with Professor Karin Schwarz and Dr Anja Steffen-Heins.

© pur.pur

Food technologist Dr Julia Keppler characterises amyloid protein structures and their properties.

Dr. Julia Keppler
Food technology
Telephone: +49 431 880-1401

Julia Siekmann
Science Communication
Core Research Area Kiel Nano, Surface and Interface Science (KiNSIS)
Telephone: 0431/880-4855

Details, which are only a millionth of a millimetre in size: this is what the priority research area "Kiel Nano, Surface and Interface Science – KiNSIS" at Kiel University has been working on. In the nano-cosmos, different laws prevail than in the macroscopic world - those of quantum physics. Through intensive, interdisciplinary cooperation between physics, chemistry, engineering and life sciences, the priority research area aims to understand the systems in this dimension and to implement the findings in an application-oriented manner. Molecular machines, innovative sensors, bionic materials, quantum computers, advanced therapies and much more could be the result. More information at