Optimisation of a blend of emulsifier substitutes for clean-label artisanal ice cream

The present work aims at the optimisation of a blend of natural ingredients (i.e., citrus fibres - CF, α-cyclodextrin - ACD, and whey protein concentrate - WPP) to be used as substitute of mono- and di-glycerides of fatty acids (MDG) in clean-label ice cream. According to a I-Optimal mixture design, fourteen formulations were produced and characterized (ice cream mix density, soluble solid content, rheological behaviour; ice cream overrun, firmness, melting behaviour, colour); as a comparison, a reference ice cream (REF) containing MDG was also prepared and tested. Applying the Response Surface Methodology, significant models (p ≤ 0.01), mainly linear and quadratic, were calculated for all the response variables and then used for the optimisation of the substitute blend, with the following targets: maximising overrun; obtaining firmness, initial time of melting, and melting rate in the ranges 10–20 N, 15–18 min, and 2–3 g/min, respectively. The best solution (desirability = 0.713) resulted in an emulsifier mixture composed of 1.1 g/100 g ACD, 1.75 g/100 g WPP, and 0.16 g/100 g CF. The use of such a mixture in ice cream gave a product with characteristics similar to REF or even better, thus demonstrating the possibility to produce a high-quality clean-label ice cream.