Understanding Acid Casein Curd Particle Properties and Their Role in Washing Efficiency

About the Project

The Friesland-Campina funded scholarship provides a tax-free stipend of NZ$35,000 per annum and covers all tuition fees and research costs. The successful applicant will be supervised by Associate Professors Alistair Carr and Lara Matia-Merino from Massey University.

Project Overview: Acid casein manufacture is a cornerstone of the dairy industry, supplying the raw material for caseinates and a wide range of casein-derived ingredients used in foods, beverages, and technical applications. Although the industrial process is well established, the underlying science remains incomplete, particularly with respect to the physical nature of acid casein curd particles and their behaviour during downstream processing.

When milk is acidified to the isoelectric point of casein, casein micelles aggregate and precipitate to form curd particles. In practice, these particles can differ markedly in size distribution, shape, mechanical firmness, surface stickiness, and internal porosity. Such differences are widely believed to control critical aspects of processing performance, including washing efficiency, fines generation, filtration behaviour, and equipment fouling. However, these particle properties are rarely measured directly, either in industry or in academic research.

At present, there is no standard toolkit for characterising acid casein curd particles, and limited mechanistic understanding of how processing variables, such as acidification rate, acid type, temperature, calcium balance, protein concentration, or milk pre-treatment, govern particle formation and particle properties. This PhD project aims to close this gap by developing a systematic, mechanistic understanding of the properties of acid casein curd particles, from their formation through to their behaviour during washing. While the work will be conducted at laboratory scale, the outcomes will be directly relevant to industrial casein and caseinate manufacture by providing a science-based framework for interpreting process variability and identifying leverage points for improvement. The project is well-suited to a student who enjoys translating physical and chemical understanding into practical measurement and testing strategies.

Candidate Profile

We are seeking a motivated and creative candidate with:

• A strong background in food science, dairy science, chemical or process engineering, materials science, or a related discipline with a minimum of a First or Second Class Honours (Division 1) MS/MSc degree (or equivalent).
• Excellent written and oral communication skills (IELTS score of 6.5 or equivalent required, if English is not the first language).
• Interest in soft matter, colloids, food texture and structure, or process–structure–function relationships.
• Strong experimental skills capable of developing, adapting, and validating experimental methods rather than relying solely on published protocols.
• A strong ability to critique both literature and one's own work in a logical and quantitative manner.
• Experience with material science (textural and rheological properties), particle characterisation (i.e, size, charges, porosity), or dairy systems is advantageous but not essential.
• Diligence, resilience and enthusiasm, with good interpersonal skills.

How to apply: Applications containing, (1) a covering letter outlining why you are suited for this project based on the criteria above, (2) your current CV, (3) official transcripts, and (4) the names and contact details of three academic references should be sent by email directly to Associate Professor Alistair Carr at a.j.carr@massey.ac.nz, clearly stating Reference FC-AC2026 in the e-mail subject line.

Applications close on Monday, 15 June 2026.

Funding Notes

The Friesland-Campina funded scholarship provides a tax-free stipend of NZ$35,000 per annum and covers all tuition fees and research costs.