International Dairy Journal 13 (2003) 621–630 Review The role of processing and matrix design in development and control of microstructures in dairy food production—a survey U. Kulozik a, *, A. Tolkach a , S. Bulca a , J. Hinrichs b a Technische Universit . at M. unchen, Chair for Food Process Engineering and Dairy Technology, D-85350 Freising-Weihenstephan, Germany b Universit . at Hohenheim, Institute for Food Technology, D-70599 Stuttgart, Germany Received 6 January 2003; accepted 4 June 2003 Abstract New options to process dairy products by means of new single unit operations or combinations thereof are presented. The innovative possibilities discussed in this paper mainly refer to novel ways of influencing product microstructures or textures as perceived during consumption, by means of contributions of single molecule fractions of complex systems derived from membrane fractionation techniques. In addition, options to integrate physiologically active components which also have a structure forming effect in fermented or other dairy products are highlighted. Alternatives derived from thermal, mechanical and enzymatic processing and from fractionation techniques by means of membranes are presented which can be exploited for fractionation and compositional matrix design of dairy products. r 2003 Elsevier Ltd. All rights reserved. Keywords: Microstructure; Thermal processing; Ultrahigh pressure; Membrane filtration; Enzyme technology ARTICLE IN PRESS Contents 1. Introduction ................................................ 622 2. Thermal processing technology ....................................... 622 2.1. Effect of milk pre-heating on the yoghurt texture .......................... 622 2.2. Whey protein structures through heat induced particulation ..................... 623 2.3. Thermal fractionation of whey proteins ............................... 624 3. Ultrahigh pressure technology ....................................... 624 4. Enzyme technology ............................................. 626 4.1. Enzymatic protein crosslinking by transglutaminase ......................... 626 4.2. Enzymatic lactose hydrolysis post-fermentation ........................... 626 5. Membrane technology ........................................... 627 6. New technologies for new nutritional concepts ............................... 628 6.1. Calcium retention in fresh cheese .................................. 628 6.2. Caseinoglycomacropeptide (CGMP/CMP) .............................. 629 7. Conclusion and outlook .......................................... 629 References .................................................... 630 *Corresponding author. Tel.: +49-8161-714205; fax: +49-8161-714384. E-mail address: ulrich.kulozik@wzw.tum.de (U. Kulozik). 0958-6946/$-see front matter r 2003 Elsevier Ltd. All rights reserved. doi:10.1016/S0958-6946(03)00141-9