Zeta potential of pectin-stabilised casein aggregates in acidified milk drinks

• Published in: International dairy journal 2007-04, Vol.17 (4), p.302-307
• Main Authors: Tholstrup Sejersen, Marie, Salomonsen, Tina, Ipsen, Richard, Clark, Ross, Rolin, Claus, Balling Engelsen, Søren
• Format: Article
• Language: English
• Subjects: acidified milk; Acidified milk drinks; beverages; Biological and medical sciences; casein; desorption; dimensional stability; electrical charges; Electrophoretic mobility; food additives; Food industries; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; Heat treatment; mechanism of action; Milk and cheese industries. Ice creams; particles; Pectin; pectins; product quality; protein aggregates; protein structure; Stability; stabilizers; surface active properties; Zeta potential
• ISSN: 0958-6946; 1879-0143
• DOI: 10.1016/j.idairyj.2006.03.003

High-methoxy (HM) pectin is commonly used to improve the stability of acidified milk drinks (AMDs) and zeta potential measurements can aid in elucidating the mechanisms responsible for the improved stability. Pectin was added to an AMD model system in concentrations of 0.0%, 0.1%, 0.3% or 0.5% and the samples were subjected to heat treatment at 75 °C for 20 min; control samples were not heated. A change in zeta potential from positive to negative values with addition of pectin was observed. Increasing the pectin concentration resulted in a more negative zeta potential. Heat treatment caused a decrease in the numeric value of the zeta potential, which indicates a partial desorption of pectin from the protein aggregates.