CHARACTERIZATION OF ICE RECRYSTALLIZATION IN ICE CREAM DURING STORAGE USING THE FOCUSED BEAM REFLECTANCE MEASUREMENT

摘要

Ice recrystallization was investigated in two commercial and differently formulatedrnice creams using a rapid and real time granulometric method: the focused beamrnreflectance measurement. Ice cream A (with locust bean gum as primary stabilizer)rnand ice cream B (with carrageenan as primary stabilizer) were stored for 154 daysrnat four different temperatures (-5, -8, -12 and -18℃) and three amplitudes ofrntemperature fluctuations (± 0.1℃, ± 0.75℃, ± 2.5℃). Crystal size distribution wasrnassessed at regular time intervals and recrystallization kinetic data was derived byrnfitting the experimental results to the asymptotic Ostwald ripening model. Asrnexpected, recrystallization rates increase with mean storage temperature andrnamplitude of temperature fluctuations. Carrageenan seems to be more effectivernthan LBG in slowing down ice crystal growth during storage. Mean ice crystal sizernincreased as a function of time~(1/3) for both ice creams. The temperature dependencernof recrystallization rate fitted Arrhenius well, with activation energies fairly similarrnfor both ice creams.