Commercial dried food emulsions, with high fat content (50 g fat /100 g), were prepared at plant scale
from whey and palm oil. Five powders were analyzed: powder without fines, taken from the bottom
of the spray-dryer chamber; fines 1 and fines 2 respectively collected at the bottom of the first and second
cyclones, a mix of fines 1 and fines 2 and the final powder, taken during packing. Scanning electronic and
optical microscopy showed only spherical particles and also indicated that fines 2 were roughly twice as
smaller as other powder particles. Free fat content was significantly higher in fines than in final powder.
Reconstituted emulsions (10 g powder/100 g water) were analyzed by laser light scattering. Aggregation
and coalescence indexes were very low, except in reconstituted emulsions made with fines 2. This is consistent
with their high free fat content and suggests that this results from processing through the cyclones.