A review of this practice, Yale's Chemical Safety Committee has concluded that only food-grade liquid nitrogen should be used for this. Food-grade liquid nitrogen is more expensive and is supplied only in larger quantities (150 liters). Food-grade liquid nitrogen must meet more rigorous tolerances for purity. We found only one instance for which this was purchased, so we are in a quandary policy-wise.
We also found that most transfer dewars have debris and other contaminate in them. These can easily end up in the ice cream.
Although we are concerned about purity and contamination, we have not found an instance where this has caused an illness, but we believe the risk exists.
Safety seems to take the fun out of everything. It's what we do.
Peter A. Reinhardt
Director, Office of Environmental Health & Safety
135 College St., Suite 100
New Haven, CT 06510-2411
From: ACS Division of Chemical Health and Safety [mailto:DCHAS-L@PRINCETON.EDU]
On Behalf Of Melissa Anderson
Sent: Thursday, September 22, 2016 4:30 PM
Subject: [DCHAS-L] Liquid Nitrogen Ice Cream
I have a colleague who's interested in making liquid nitrogen ice cream as an outreach activity and he asked me about safety/risk implications. Does anyone have any experience with this from a risk assessment perspective?
Pasadena City College
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