Retail-manufactured ice cream samples formulated with 8% fat (milk cream) were produced in triplicate in a batch freezer, either with or without mix homogenization (16MPa) and ageing (24h). For comparison, ice cream samples formulated with 8% vegetable fat (coconut oil) were also produced in triplicate using both aged and non-aged homogenized mixes. Fat-globule-particle size distribution and the kinetics of protein desorption during mix ageing were investigated together with ice cream overrun, firmness, free-fat and melting properties. When homogenization was not applied, as traditionally done by artisan ice cream producers, the level of adsorbed protein and the physical characteristics of cream-based ice cream were not affected by mix ageing. On the contrary, ageing of both cream and coconut oil homogenized mixes caused protein desorption, and free-fat reduction and melting-rate increase in ice creams. The level of adsorbed proteins per unit fat-globule area was almost double when vegetable fat was used in homogenized mixes. However, those proteins were quickly desorbed during mix ageing. The protein desorption phenomenon was quite less evident in cream-based formulations. No significant effect of mix ageing and homogenization were observed on ice cream overrun and firmness.
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