During marzipan production, almond kernels are blanched, skinned and finely ground, and then processed with sugar to form raw marzipan paste. When peeling the almonds, the almond skin and the scalding water accumulate as waste materials. So far, these have been used either for biogas production or as feed and fertiliser. But the almond skin contains valuable antioxidants that protect the human body from free radicals, which are aggressive oxygen compounds that can damage body cells. Due to their beneficial health effects, antioxidants are potentially valuable substances for health care and cosmetic products as well as food and dietary supplements.

Within the framework of the VEREMA project at the THL, chemist Veronika Hellwig has set herself the task of extracting the antioxidants from almond skin and scalding water to determine their chemical structures and potential effects. To this end, extracts – that is, mixtures of several hundred individual substances – are first extracted from the almond skin and the scalding water and tested for their antioxidant and antibiotic effects. The extracts are then separated into their individual substances and these are tested again. Thus, the chemical structures of the individual substances can be determined and their biological properties as well as their utilisation potential can be tested. The substances are then chemically modified so that they have, for example, improved solubility and can be absorbed more quickly by the body.

After Hellwig and her team have determined the effectiveness of individual substances, they develop an economic concept that shows which industries will be best suited to use and market antioxidants in the future. The extraction of antioxidant ingredients is not meant to be carried out at the marzipan production site, but directly at the end user – such as a cosmetics company or a pharmaceutical manufacturer.

The Federal Ministry of Education and Research is supporting the research project with about 430,000 euros within the framework of the IngenieurNachwuchs funding line as part of the Research at Universities of Applied Sciences programme.