|
|
||||||||


* Biological Systems Engineering Department, Washington State University, Pullman 99164-6120
Department of Food Science and Human Nutrition, Washington State University, Pullman 99164-6376
Corresponding author:
G. V. Barbosa-Cánovas; e-mail:
barbosa{at}wsu.edu.
The combined use of high hydrostatic pressure (300 to 676 MPa, 5 min) and thermal treatment (85°C, 30 min) in milk for the manufacture of low-fat yogurt was studied. The objective was to reduce syneresis and improve the rheological properties of yogurt, reducing the need for thickeners and stabilizers. The use of high hydrostatic pressure alone, or after thermal treatment, reduced the lightness and increased the viscosity of skim milk. However, milk recovered its initial lightness and viscosity when thermal treatment was applied after high hydrostatic pressure. The MALDI-TOF spectra of skim milk presented monomers of whey proteins after a treatment of 676 MPa for 5 min. Yogurts made from skim milk subjected to 400 to 500 MPa and thermal treatment showed increased yield stress, resistance to normal penetration, and elastic modulus, while having reduced syneresis when compared to yogurts from thermally treated or raw milks. The combined use of thermal treatment and high hydrostatic pressure assures extensive whey protein denaturation and casein micelle disruption, respectively. Although reaggregation of casein submicelles occurs during fermentation, the net effect of the combined HHP and thermal treatment is the improvement of yogurt yield stress and reduction of syneresis.
Key Words: high hydrostatic pressure syneresis yield stress yogurt
Abbreviation key:
-La =
-Lactalbumin, ß-Lg = ß-Lactoglobulin, HHP = high hydrostatic pressure, WHC = whey holding capacity
This article has been cited by other articles:
![]() |
A. Hernandez and F. M. Harte Manufacture of Acid Gels from Skim Milk Using High-Pressure Homogenization J Dairy Sci, October 1, 2008; 91(10): 3761 - 3767. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Aziznia, A. Khosrowshahi, A. Madadlou, and J. Rahimi Whey Protein Concentrate and Gum Tragacanth as Fat Replacers in Nonfat Yogurt: Chemical, Physical, and Microstructural Properties J Dairy Sci, July 1, 2008; 91(7): 2545 - 2552. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |