Improving the whey protein foam structures by using novel acetylated triglycerides: A response surface methodology (RSM) approach

Abstract

AbstractProtein foams are common to foods, such as meringue, whipped cream and mousses. Stability is a challenging issue determined by fat and sugar content. We hypothesize that acetyl‐triacylglycerols (acetyl‐TAG) that possess sn‐3 acetate group with high oleic content can provide stability to the foam at reduced sugar concentrations by increasing the surface viscosity and minimizing serum drainage. A fractional factorial Box‐Wilson design was used to investigate the effects of whey protein concentration (WPI) (2–10 wt%), sucrose concentration (SC) (10–30 wt%) and acetyl‐TAG concentration (ATC) (0–1 wt%) on overrun (FO), stability against serum drainage (FD) and surface dilatational rheology. Each response was analyzed by linear regression model fitting and a backward elimination algorithm for significance (α = 0.01). FO was significantly affected (p < 0.01) by WPI and ATC, but not sucrose concentration. The optimum overrun (nearly 700%) was obtained at 9 wt% WPI and 0.6 wt% ATC. Drainage and viscoelastic properties were significantly (p < 0.01) affected by all process variables. Dynamic complex modulus (|E|) as measured using an optical tensiometer was around 30–40 mN/m when acetyl‐TAG was higher than 0.5 wt%. Our findings indicated that the acetyl‐TAG can be used to enhance the stability of protein foams in reduced sugar food products, however, not at high sugar concentrations (30 wt%).