PhD fellowship in Soft Matter physics and Food Science Full-time

PhD Fellowship In Colloidal Research In Food Science

The Department of Food Science and the Niels Bohr Institute invites applicants for a PhD fellowship in colloidal research in food science. The PhD project has the overall goal of describing the molecular structure of casein micelles through computational and experimental investigations, with focus on the role of κ caseins. The candidate will be part of the CaIFF center for the use of neutron for the investigation of colloids and interfaces in food science and pharmacy.

Expected start date is 1 January 2027 or as soon as possible thereafter.

Background. Casein micelles (CMs) are the main protein constituent of milk (80% of protein) and defining for dairy product taste and structure. CMs are 100-200 nm globular particles, formed by a hydrated network of disordered casein proteins, named αS1, αSs, β, and κ casein. The caseins are cross-linked through binding to ionic calcium and colloidal calcium phosphate, and through hydrophobic interactions. Post-translational modifications play an important role in this, as the ionic interactions are largely mediated by casein phosphorylation sites. The CMs are stabilized by κ caseins that are believed to form a hairy layer on the CM surface. Therefore, κ caseins are particularly important for CM stability. κ caseins moreover contain a rennet cleavage site, separating its anchoring para κ casein domain from the water-soluble caseinomacropeptide, the primary component of the stabilizing hairy layer. Enzymatic cleavage of this site promotes coagulation and curd formation.

Goal. Despite decades of research, central questions remain regarding the CM structure, their molecular organization, and dynamic behaviour. The goal of the PhD project is to answer fundamental questions like: are all caseins needed for CM formation? What is the role of post-translational modifications in the casein-calcium network formation, and in the κ casein hairy layer? How extended is the stabilizing hairy layer, and how does it depend on for example pH or solvent? What is the dynamic exchange of caseins between soluble caseins or other CMs? In other words, the PhD project's aim is to understand the molecular interactions in CM which are central to the unique food properties of dairy products like milk, cream, and cheese, with a particular focus of κ casein.

How. Methodological strategy involves state-of-the-art molecular dynamics simulations for building a molecular model of casein micelles. Advanced x-ray and neutron scattering experiments, will be used to validate the model. Scattering experiments provide information of the hierarchical structure of CMs, whereas molecular simulations model the molecules and their interactions. The combination of simulations and scattering data is particularly strong, as the simulated molecular predictions can be validated experimentally. The project thus involves preparing samples, collecting and analysing scattering data and complementary data when needed, and running MD simulations and comparing these to the experimental data.

Societal impact. By understanding casein micelles better, the project supports the development of more sustainable dairy products based on plant-based or precision fermented proteins. Such approaches could remedy the green house gas emissions and adverse effect on biodiversity and animal welfare in traditional dairy production.

Who are we looking for?

We are looking for applicants with a strong background in molecular modelling, for example applied to food or structural biology. Experience with any of the following is an advantages:

• Molecular dynamics (MD) simulations; coarse-grained force fields, for example Martini.
• Small-angle x-ray scattering (SAXS), small-angle neutron scattering (SANS) or other x-ray or neutron scattering experiments.
• Programming, for example use of Python and GitHub.
• Data analysis, inverse problems and statistical analysis.
• Mathematical understanding, knowledge of integration, Fourier transformation etc.
• Wet lab experience; protein purification, experience with with colloidal and self-assembled systems.

Finally, the candidate needs to posses good written and oral communication skills.

Our group and research – and what we offer?

You will be part of a very strong cross-institutional and international research environment through the CaIFF center. This means that other PhD students will start approximately at the same time, and you will be part of a unique network of young researchers in the center. You will be supervised by newly appointed tenure track assistant professor Andreas Larsen as well as associate professor Jacob Kirkensgaard, who are affiliated with the Department of Food science and the Niels Bohr Institute at University of Copenhagen. Thus, you will be in a research environment focusing on self-assembly, dynamic structure formation within food science, but also have colleagues in the related field of polymer science and soft matter. You will get regular supervision and be part of a lively research group with students at all level from BSc to PhDs and postdocs. A strong methodological focus core technique in the group is on the use of x-ray and neutron scattering experiments to probe structure and molecular self-assembly at the nanometer-scale.

The Departments offers unique facilities. Department of Food science have state-of-the art laboratory facilities for sample preparation and characterization. Computational resources are available through national and European supercomputer facilities LUMI and Computerome, along with local small-scale GPU resources at the Niels Bohr Institute. Local SAXS instrument are available at both institutes, and managed through the cross-disciplinary X-ray center (CXC), and thereby readily available for the project. Only one hour from the University of Copenhagen, in Lund in Sweden, there is access to the world-class x-ray synchrotron MAX-IV, and the project involves SAXS experiments there. Moreover, the group regularly visits neutron facilities in Europe, and will be frequent users of the neutron facility European Spallation Source (ESS) also in Lund, which is expected to open for users during 2027.

Principal supervisor is associate professor Jacob Kirkensgaard, Niels Bohr Institute and the Department of Food Science, University of Copenhagen.

Co-supervisor is tenure-track assistant professor Andreas Larsen, Niels Bohr Institute and the Department of Food Science, University of Copenhagen.

The PhD programme

Qualifications needed for the regular programme To be eligible for the regular PhD programme, you must have completed a degree programme, equivalent to a Danish master's degree (180 ECTS/3 FTE BSc + 120 ECTS/2 FTE MSc) related to the subject area of the project, e.g. [relevant educations]. For information of eligibility of completed programmes, see General assessments for specific countries and Assessment database.

Terms of employment in the regular programme Employment as PhD fellow is full time and for maximum 3 years.

Employment is conditional upon your successful enrolment as a PhD student at the PhD School at SCIENCE, University of Copenhagen. This requires submission and acceptance of an application for the specific project formulated by the applicant.

Terms of appointment and payment accord to the agreement between the Danish Ministry of Taxation and The Danish Confederation of Professional Associations on Academics in the State. The position is covered by the Protocol on Job Structure.

You can read more about salary levels in the state sector www.loenoverblik.dk (in Danish).

Responsibilities and tasks in the PhD programme

• Carry through an independent research project under supervision
• Complete PhD courses corresponding to approx. 30 ECTS / ½ FTE
• Participate in active research environments, including a stay at another research institution, preferably abroad
• Teaching and knowledge dissemination activities
• Write scientific papers aimed at high-impact journals
• Write and defend a PhD thesis on the basis of your project

We are looking for the following qualifications:

• Professional qualifications relevant to the PhD project
• Relevant publications
• Relevant work experience
• Other relevant professional activities
• Curious mind-set
• Good language skills

Application and Assessment Procedure

Your application including all attachments must be in English and submitted electronically by clicking APPLY NOW below.

Please include:

1. Motivated letter of application (max. one page)
2. Your motivation for applying for the PhD project
3. Curriculum vitae including information about your education, experience, language skills and other skills relevant for the position
4. Original diplomas for Bachelor and Master and transcript of records in the original language, including an authorized English translation if issued in another language than English