Complexed Biopolymer of Whey Protein and Carboxymethyl Cellulose to Enhance the Chemical Stability of Lemon Oil-in-Water Emulsions

• Published in: ACS food science & technology Vol. 2; no. 1; pp. 41 - 48
• Main Authors: Kaade, Wael, Méndez-Sánchez, Carmen, Güell, Carme, De Lamo-Castellví, Silvia, Mestres, Monsterrat, Ferrando, Montse
• Format: Journal Article
• Language: English
• Published: American Chemical Society 21.01.2022
• Subjects: whey protein; SPG membrane emulsification; electrostatic complex; physical/chemical stability
• ISSN: 2692-1944; 2692-1944
• DOI: 10.1021/acsfoodscitech.1c00274

Lemon oil (LO) has been used as a flavoring food additive and its encapsulation in emulsions has facilitated its incorporation in food and pharmaceutical products. d-Limonene, the main ingredient in LO, and citral, the compound responsible for the aromatic profile, are easily oxidized and a new emulsion interfacial structure is needed to protect these compounds. This paper studies the physical and chemical stabilities of LO-in-water emulsions produced by membrane emulsification as a function of the oil droplets’ surface electric charge and interfacial thickness. For that purpose, the different stabilizers used were whey protein (pH: 3.8 and 6.8), and, for the first time in lemon oil encapsulation, an electrostatic whey protein–carboxymethyl cellulose (WP-CMC) complex (pH: 3.8). Although this complex did not improve emulsions’ physical stability when it comes to droplet size, it has contributed to maintaining the emulsions’ original color. As for chemical stability, the WP-CMC complex decreased the production of off-flavors resulting from the deterioration of d-limonene and citral under accelerated oxidation conditions.