Résumé :
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It has already been reported that the size of fat globules increased and de-emulsification occurred during the ice cream manufacturing process, when drawing temperature is lowered and dasher capacity, dasher speed and overrun are increased.This paper shows the changes in fat globules in ice cream during the freezing process as observed by a laser microscope at 400 times magnification. Most of the fat globules disperse as small particles of diameter about 1.0 µm in the ice cream mix. However, after the freezing process, most of the fat globule particles were 1.0-5.0 µm in diameter at a drawing temperature of -3.5 °C. The fat globules grew to 20 µm in diameter at a drawing temperature of -4.5 °C, and huge particles of 40 µm were observed at a drawing temperature of -5.5 °C. At an overrun of 30%, most of the fat globules were about 1.0 µm and there was no difference compared with the fat globules in ice cream mix. Fat globules increased in size as the overrun increased, 5-20 µm at an overrun of 60%, 20 µm at 100%, and 50 µm at 140%.
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