title: Measurement of milk clotting activity by rotational viscometry.
abstract: Standard method for the determination of the activity of milk coagulants is the rotating bottle method, where clotting time is defined as the time when visually observable flocculation starts. Aim of this study was to verify whether it is possible to determine milk clotting time by rotational viscometry. Using three different coagulants and reconstituted milk of different pH and temperature, flocculation time and viscosity in steady shear was determined, and milk gelation was monitored by small amplitude oscillating shear rheometry. The results show that, independent of pH and temperature, milk clotting time is related to an apparent viscosity of 7.24±0.45 mPa.s, indicating that rotational viscometry can be used for the screening of flocculation time with an accuracy of approximately 6%.
authors.affiliation: Institute of Food Technology and Bioprocess Engineering, Technische Universität Dresden, 01069 Dresden, Germany.
authors.forename: Mandy
authors.initials: M
authors.lastname: Jacob
authors.affiliation: Institute of Food Technology and Bioprocess Engineering, Technische Universität Dresden, 01069 Dresden, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Schmidt
authors.affiliation: Institute of Food Technology and Bioprocess Engineering, Technische Universität Dresden, 01069 Dresden, Germany.
authors.forename: Doris
authors.initials: D
authors.lastname: Jaros
authors.affiliation: Institute of Food Technology and Bioprocess Engineering, Technische Universität Dresden, 01069 Dresden, Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Rohm
mesh_terms: D000818:Animals; D002417:Cattle; D005504:Food Analysis; D008892:Milk / Q000737:chemistry*; D012212:Rheology / Q000295:instrumentation / Q000379:methods*; D014783:Viscosity