0000000000924454
AUTHOR
D. Lorient
Thermodynamic and kinetic aspects of the transport of small molecules in dispersed systems
Abstract The knowledge of the behaviour of flavour compounds in complex multiphase systems with regard to their structure is of great importance in flavour perception of foods. The thermodynamic and kinetic behaviour of three selected flavour compounds belonging to a homologous series of esters, e.g. ethyl acetate, ethyl butanoate and ethyl hexanoate, were studied in simple and multiphase systems. The liquid system was composed of water (with or without sodium caseinate) and/or a lipid, Miglyol. First, the properties of the solutes were determined by means of their liquid–liquid partition at equilibrium and their diffusion in aqueous or lipid phases. This first step allowed to reveal the im…
Sodium Chloride and Magnesium Chloride affected by Ripening of Camembert Cheese
Ripening of cheese with three kinds of salt treatment was studied using MgCl 2 , NaCl or a mixture of the two. Proteolysis was followed by determination of TCA-soluble nitrogen and quantitative electrophoresis. A rapid one-step method for free fatty acids was used to determine short and long-chin fatty acids. In the presence of magnesium, proteolysis increased, even with NaCl, which seemed to delay the magnesium activation. Lipolysis was retarded by NaCl, which decreased the level of free fatty acids. An imbalance between proteolysis and lipolysis could be responsible for the unpleasant flavor of the cheese containing both MgCl 2 and NaCl
Contribution of Protein Flexibility to the Foaming Properties of Casein
The effect of biopolymer flexibility on the foaming properties of casein was investigated. Flexibility was altered by: (1) chemical modification (covalent binding of a monosaccharide on the lysyl residues) or (2) pH change. Electron Spin Resonance was used to measure the reorientational frequency of casein residues labeled with nitroxide radicals. High levels of glycosylation induced increased protein flexibility and improved the foaming capacity. Good agreement was observed between higher values of flexibility and improved surface properties near the isoelectric point.