Effect of emulsification and spray-drying microencapsulation on the antilisterial activity of transcinnamaldehyde

Abstract

Spray-dried redispersible transcinnamaldehyde (TC)-in-water emulsions were prepared in order to preserve its antibacterial activity; 5% (w/w) TC emulsions were first obtained with a rotor-stator homogeniser in the presence of either soybean lecithin or sodium caseinate as emulsifiers. These emulsions were mixed with a 30% (w/w) maltodextrin solution before feeding a spray-dryer. The antibacterial activity of TC alone, TC emulsions with and without maltodextrin before and after spray-drying were assayed by monitoring the growth at 30 °C of Listeria innocua in their presence and in their absence (control). Whatever the emulsifier used, antilisterial activity of TC was increased following its emulsification. However, reconstituted spray-dried emulsions stabilised by sodium caseinate had a higher antibacterial activity suggesting that they better resisted to spray-drying. This was consistent with observation that microencapsulation efficiencies were 27.6% and 78.7% for emulsions stabilised by lecithin and sodium caseinate, respectively.

• Emulsion
• Listeria
• Microencapsulation
• spray-drying
• transcinnamaldehyde

Declaration of interest

The authors declare no conflict of interest.

The authors wish to gratefully acknowledge “Conseil Général de l'Ain” and “Communauté d'Agglomération de Bourg en Bresse” for financial support and “Agence Universitaire de la Francophonie (AUF)” for Nga-Thi-Thanh Trinh PhD grant.