Emulsion gels containing n-3 fatty acids and condensed tannins designed as functional fat replacers

Abstract

The purpose of this study was to ascertain the potential of several food-grade emulsion (O/W) gels (GEs) for use as healthier fat replacers. The emulsions, formulated with a lipid phase rich in n-3 fatty acids and different emulsifiers (sodium caseinate, SC; whey protein isolate, WPI and isolated soy protein, ISP), were cold gelled after adding a natural extract rich in condensed tannins (CT). The GEs were characterized and their oxidative stability evaluated during storage (4 °C). All GEs formulated presented a solid-like structure showing generally excellent emulsion stability, which improved in GEs with the addition of CT. Non-extractable proanthocyanidins (NEPA) were the main source of polyphenol in samples enriched with CTs. The antioxidant activity of the systems was not affected by the use of different proteins as emulsifiers, but it was improved in GEs containing CT. The oxidation values recorded in the GE systems can generally be regarded as low even considering their enrichment with unsaturated fatty acids, which thus assures their suitability for use as fat replacers.