The Fine Art of Packaging

How food technologists package the substances they use in such a way that their impact is only felt where they are actually needed

What links the probiotic microorganisms in yogurt, the cocoa powder sprinkled on desserts and the flavors used in chewing gum? The answer is that they all require a certain type of “packaging”, known as a micro-capsule, which protects the ingredients and releases them precisely where their effects are required. Professor Dr. Stephan Drusch, head of the Chair of Food Technology, and his team focus on the “packaging materials” required.

Development of a packaging assembly kit within the EU joint project ENCAP4HEALTH

This does not mean that the participating researchers spend their time packing things in paper. “Packaging” here means placing a wide range of substances into capsules made of biopolymers such as pectin or vegetable protein and measuring just a few micro or millimeters. “Pectin is a polysaccharide made of plant cells. We can modify pectin using enzymes or bind it with proteins to create special functional properties for the material used in the capsules. These include acid sensitivity, specific barrier properties or even the consistency itself – solid or gel-like – depending on the application,” says Stephan Drusch.

The work being conducted is part of the EU joint project ENCAP4HEALTH initiated by the Chair of Food Technology. “Our aim is to gain a sufficient understanding of the behavior of the individual capsule elements and the processes at their interfaces to enable us to produce a type of assembly kit for producing micro-capsules with very different properties,” says Hanna Kastner. The capsules can then be used, for example, to protect probiotic substances from acidic pH in the stomach as they are guided to the bowel.

The team’s findings are in demand across a range of industries

The demand for sustainable packaging of this type is not restricted to food technology. It is also being used in areas ranging from aquaculture and pharmacy through to the nutrient industry and biotechnology.

“In general, my team explores the chemical basic structure of food ingredients, how these behave when being processed and the resulting functional properties. We are using the results of this basic research to modify individual substances or to introduce them to specific structures with particular technological and/or physiological properties,” says Stephan Drusch.

Sustainable use of pea shells and potato skins

“Many consumers are looking to feed themselves healthily and eat more vegetable proteins. Pea and potato proteins are however often not easily soluble and contain flavors. Our focus is on a gentle extraction of these proteins and adaptation of the production processes,” says Martina Klost, one of the project’s research associates.

Every year in Germany, more than 150,000 tons of peas are used for the production of starch. The pea shells are often simply disposed of although valuable ingredients such as pectin or cellulose can be extracted from them. “Both are important dietary fibers whose presence is far too low in our diets,” adds Dr. Rocío Morales who works in the Chair of Food Technology as a postdoctoral researcher. “We are working on optimizing cellulose-rich plant fibers to enable an appropriate increase of their proportions in yogurt, bread or milkshakes, without any loss of flavor or changes in consistence.” Cellulose consists of long fibers and account for the “sandy” feeling in the mouth left by many wholegrain products. These fibers have to be broken up and shortened.

“In addition to the encapsuling of valuable ingredients, my team also focuses on the sustainable use of plant materials, which until recently had been regarded as waste products of food production. By pursuing these two areas, our research links the two major societal challenges of sustainable food production and healthy eating,” concludes Stephan Drusch.

The team

Professor Dr. Stephan Drusch

“I am always eager to find out about food – both in my private everyday life and as a scientist. I studied ecotrophology at the Christian Albrecht University of Kiel, and gained my first professional experience in the area of baby foods. This is where I developed my interest in using capsules for ingredients, a topic in which I later completed my Habilitation. After two years abroad at the University of Milan, I came to Berlin to take up a professorship at the Beuth University of Applied Sciences. I have been head of the Chair of Food Technology at TU Berlin since 2011.”

Dr. Hanna Kastner

“The junior research group I lead conducts research into micro-capsuling. Our goal is to develop and test new ideas and incorporate them into the widest possible range of food systems. The ENCAP4HEALTH project enables us to draw on an international exchange of experiences and findings to generate pectin-protein-based micro-capsules, and to examine in detail the release of the contents of these capsules. The advancement of junior scholars is a topic very close to my heart.”

Dr. Rocío Morales

“I studied chemical engineering in Granada, Spain and first came into contact with TU Berlin’s Chair of Food Technology while doing my doctorate. After completing my doctorate, I transfered fully to TU Berlin to conduct research into dietary fiber. This enables me to gain a more global expertise in the area of food processing. What interests me most about my work is that I learn something new every day as a result of the new questions I am always being asked - students are really creative in this respect! Research is an ongoing process based on creativity and the desire to find out about things, as well as the challenges of society and industry.”

Martina Klost

“What I really like about food technology is working at the interface between basic research and development using regional and sustainable raw ingredients. My work is part of the Federal Ministry of Education and Research’s NutriAct project to develop eating habits for healthy aging. In the interdisciplinary sub-project focusing on new products, we are working on dietary fiber, unsaturated fatty acids and vegetable proteins. My area of focus is the functional properties of pea protein, a regional and sustainable alternative to animal proteins.”