Flavour release study as a way to explain xanthan–galactomannan interactions

• Published in: Food hydrocolloids 2007-12, Vol.21 (8), p.1237-1244
• Main Authors: Secouard, Sébastien, Grisel, Michel, Malhiac, Catherine
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; chemical interactions; Chemical Sciences; Critical overlapping concentration; flavor; Flavour release; Food additives; Food industries; food matrix; food technology; Fundamental and applied biological sciences. Psychology; Galactomananns; galactomannans; General aspects; hydrophobicity; Limonene; mixtures; Phase separation; Polymers; rheological properties; synergism; Synergistic interactions; volatile compounds; Xanthan; xanthan gum
• ISSN: 0268-005X; 1873-7137
• DOI: 10.1016/j.foodhyd.2006.07.011

In spite of numerous studies and abundant literature, xanthan(X)/galactomannan(GM) interactions still remain controversial while such mixtures have been intensively employed for a long time. The present work aims to bring new highlights on the nature of the interactions involved between both polysaccharides through an original approach: the behaviour of small volatile solutes in water-based X/GM solutions and mixtures. To this aim, a study of limonene release from X/guar (X/G) and X/carob (X/C) water-based mixed solutions has been investigated in the dilute and semi-dilute polymer concentration regimes. The aroma compound release from both matrices was compared together with the rheological properties of the solutions. When considering the limonene release as a function of the concentration regime, a dramatic decrease of the limonene release was observed for the X/C mixtures in the neighbourhood and above the critical overlap concentration C*. This result combined with kinetic experiments allowed to state the occurrence of specific interactions between limonene and polymeric junction zones formed in the X/C matrices. The apolar nature of the aroma compounds used allows to consider the nature by itself of the interactions responsible for volatile retention to be hydrophobic. A different mechanism for synergistic interactions between X and G was observed. The synergy appears quite lower than X/C mixtures and can be explained by phase separation occurring in the X/G mixture, favoured by ordered conformation of X.