This same question was asked a couple days ago (nned to look at other topics before posting, someone might have same question). Here is the thread:
http://www.finescale.com/fsm/community/forum/topic.asp?TOPIC_ID=34692
I personally don't use foodstuff (baking soda/powder, or flour) for dio snow. It will yellow and/or be eaten by bugs over time. Woodlands Scenics Snow is the best product out there.
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